# How Are You Mounting Your Pm1340gt Lathe?



## sanddan (Jan 16, 2016)

I want to hear from the owners of the PM1340GT lathe, how are you setting your lathe on the floor? There are several possibilities using the standard stand supplied with the lathe. The factory designed the stand with 4 threaded holes and supplied bolts to be used to level the lathe and then use the larger holes to anchor the lathe to the floor using threaded studs in the concrete. Other options are leveling feet of different types or just sitting on the floor. Please let me know what you did and why you chose that particular method.


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## zmotorsports (Jan 16, 2016)

I have mine sitting on TECO adjustable feet.  That is how I leveled mine as well.

Mike.


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## wrmiller (Jan 16, 2016)

I followed Mike's setup. Works great for me.


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## mksj (Jan 17, 2016)

Have not had any vibration issues with the lathe, but initially put on Mason large metal cupped feet, I used heavy washers on either side and locking nuts. I do not use the threaded hole and keep the distance between the feet and base as close as possible. Have a set of TE-CO metal adjustable feet like Mike & Bill's, just haven't gotten around to switching them. But have had no issues with the Mason's even though they are a no, no. Also have the Mason feet on the mill and they have worked well.


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## RIO (Jan 17, 2016)

I bought the same thing as Mike and Mark are using, just got mine from ENCO.
It's not working for me.  Maybe my expectations are too high, but if I bump the headstock with my hand, it shakes.  Matt said to take the adjustable feet off and use the bolts that came with it.  I did, and it's no better. However, he said the main key is bolting it down, which I can't do.  In-floor radiant water circulated heat lines.  Can't drill the concrete floor.
I've got other ideas that will require a lot of time, work, and money to get this thing rock solid, the way it should [must] be to do precision work.  The best fix for other guys would probably be to bolt it down, I just wish I could.
What it really needs is a ONE PIECE CAST IRON STAND.  Matt says he has tried, but it's too costly.  I say, please do it anyway, Matt, and add it to your options list:
Example:  "Upgraded, one piece case iron stand:  $500", or whatever it costs, I'd buy it.  What a shame to have a 6-7k dollar high precision lathe, and not have a stand that allows it's potential.

Also still trying to figure out why my compound slide bound up.  I'm sure Matt will make it good, but I've wasted hours working on something that I shouldn't have had to, and it still won't work.  Hope I find out it was my fault.

Still no chips.

RIO


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## wrmiller (Jan 17, 2016)

That is interesting because I've not noticed any shakes or vibrations on mine. But I am only one example, and have no idea what the difference might be.


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## mksj (Jan 17, 2016)

The machine with base weighs ~1300 lbs, the base maybe 250lb, other lathes in this size come in at a  similar weight category. I think there is the over expectation of rigidity that one should expect from the base. It just isn't going to be unless you add a massive base and a 1000lbs. There are other HD lathes, with cast iron bases they weigh in at at over a ton, they are more expensive then the PM1340GT, and you would end up paying twice as much for a machine made in Taiwan (like an ERl1340).  Even if a cast iron base was available, the shipping costs and ability to deliver it at a reasonable price would be problematic. You can turn the cabinets upside down and pour concrete into the bottoms to mass load the bottom of the bases, and add some structural steel across the back of the cabinets to brace them. Agree the bases could be heavier and more rigid, but in using the machine I am not aware of any current individuals using this lathe that  have issues with finish or tolerance.


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## wrmiller (Jan 17, 2016)

mksj said:


> The machine with base weighs ~1300 lbs, the base maybe 250lb, other lathes in this size come in at a  similar weight category. I think there is the over expectation of rigidity that one should expect from the base. It just isn't going to be unless you add a massive base and a 1000lbs. There are other HD lathes, with cast iron bases they weigh in at at over a ton, they are more expensive then the PM1340GT, and you would end up paying twice as much for a machine made in Taiwan (like an ERl1340).  Even if a cast iron base was available, the shipping costs and ability to deliver it at a reasonable price would be problematic. You can turn the cabinets upside down and pour concrete into the bottoms to mass load the bottom of the bases, and add some structural steel across the back of the cabinets to brace them. Agree the bases could be heavier and more rigid, but in using the machine I am not aware of any current individuals using this lathe that  have issues with finish or tolerance.



I am having no issues with finish or tolerance and can easily hold tenths on mine.


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## RIO (Jan 17, 2016)

Sorry for the negative attitude in that last post boys.  Have been going on little sleep for too long, and I'm raising a kindergartner on my own, and I'm too old for both.  HA.  Matt doesn't deserve any trouble, he works extremely hard to keep happy customers.  Other severe friction [woman] in my life is causing my impatience.  Apologies.

As usual, Mark [MKSJ] explains things very well, and puts it into great light.  Very good perspective.  Bottom line, my expectations were a little lofty.

I guess I should level this thing up the best I can, then put it into service, and see how the work comes out before I b*^ch any more about it.  Might turn out awesome work anyway.

As I sit and stare at this thing, one thing does jump out at me:  THE MARATHON MOTOR HANGING OFF THE BACK, IS A LOT HEAVIER THAN STOCK.  An unexpected consequence.    And looking at the machine from the side, it is obvious that directly exacerbates the issue.  The shake isn't in the length of the machine, it's in the depth.  I would humbly submit five suggestions for Matt that I think will help greatly:
1.)  The plates that are welded up under the top of the stand, that the lathe bolts directly to are are two pieces.  If that was one thick, solid plate across the top, I believe that would help the lateral stability a noticeable amount.  Then take those flimsy shelves out of the middle of the stand sections and make them 5/16 steel plates.
2.)  Widen the lateral (depth) stance of the stands so the feet are a few inches further apart.  In other words, make the stand sections bigger front-to-back.  That will make it a lot less top heavy, making it more solid.
3.)  Make the stand a one-piece welded together unit, by simply adding welded angle iron braces across the top and bottom.  I understand this will make shipping and transit more cumbersome, but well worth it.  Make it an added option if you need to.
4.) Thread those 3/4 inch holes in the bottom and put large, adjustable 3/4 inch feet on there, and make the 1/2 inch hole for anchoring it down.
5.) Pour the stands full of molten lead.  [Joking]

The main concern here is I am worried that any shake/vibration in the machine will cause reamer chatter when chambering these match barrels.  Guess I should have just saved up another 10 grand and bought a bigger lathe if that was the concern.  However, the main draw for a gunsmith with this machine is the short headstock combined with a large spindle bore, therefore being able to chamber a 20" barrel through the headstock.  Nearly impossible to find that combination in a bigger, non-China lathe.

I guess the other option is take the lathe off the stand, bolt it to the floor, and do my work lying on my belly?

Maybe I should just stop obsessing about perfection and just play along in the sandbox of life.
Thanks for the help.
RIO


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## mksj (Jan 17, 2016)

Rio,

I hear you and agree. You may want to beef up the stands, I am pretty sure it will work out well. There was a thread with a G4003G owner beefed up his bases with square tubing and others where they weighted the bases. I have also heard of putting some sandbags in the base. Gave him some additional machine height widened the stance, looked really rigid. I would tie the bases together top and bottom. I am serious about pouring cement into the bases to increase the mass and the dampening. I have made speaker stands, poured cement in the metal frame/base and it was dead quiet with the knuckle test.
http://www.hobby-machinist.com/threads/new-g4003g-lathe.15636/#post-123851

The Marathon motor is a TENV, they require a lot more iron and fins to dissipate the heat, they are supposedly quieter and have less vibration then the TEFC version. I believe having wider mounting feet bracing would go a long way, this is similar to what Dan did for his smaller Enco (nicely done). This is the customization part that each machine owner does for their machines to get them to where they want.


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## sanddan (Jan 17, 2016)

I hope that everyone that has responded with posts has also voted.

I have tried both the Teco steel swivel feet and Mason isolating feet, both with 1/2" studs. The Mason feet allowed too much movement for me.

I wanted to see what other people are doing and if they like/dislike their choice. If anyone has bolted their lathe to the floor I would love to hear how they feel about doing that. Stability, vibration and any other comments they might have.

Thanks to everyone who has responded.


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## Steve Shannon (Jan 17, 2016)

Probably a stupid question, but what about pouring a concrete base in place or even encasing the feet of the stand with poured concrete? 


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## RIO (Jan 17, 2016)

Mark, your advice and information never fails to help.
You have to watch what you tell me though, like "I would add a Marathon E467".  Next thing you know, it's on my machine.  So, the same with pouring the stands full of concrete......stand by for pictures...   

I think the main thing I am hearing from Matt is BOLT THE STAND DOWN, AND IT MAKES A HUGE DIFFERENCE.  Unfortunately, I absolutely can't drill my concrete, unless I like playing Russian roulette with likely hitting a radiant heat water line that's buried in the floor.  Otherwise, if you are having instability issues, I absolutely would do that next......in addition to pouring the stands full of concrete   

Thinking specifically, what I intend to do before I take the lathe back off the stand, is spot weld the 4 bolt heads up under, inside the stands right now that hold the lathe on.  Otherwise, if I fill it will concrete, how would I then bolt the lathe back on the stand?

This could be fun....after filling with concrete, put the doors back on and reassemble.  Then holler to a visiting friend to go get a wrench for me out of the cabinet under the lathe, and watch his reaction when he opens the cabinet door.

Another idea [serious this time] is to tap those 3/4 inch holes on the bottom, and use much bigger leveling feet.  I expect that to help also.


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## Muskt (Jan 17, 2016)

I do not have a 13x40.  I have a 12x36.  I fabbed my own base to go under the supplied cabinets.  I used all metal feet with 1/2x13 bolts being the support.
When I first got the lathe up & running, I was seriously upset with the finish on everything I turned.  Couldn't understand the reason behind the lousy finish.  Then I noticed the work light shaking or swaying, kind of like a drunken sailor on shore leave.  I had already leveled the machine with a Starrett machinist level.  It does sit on a concrete floor.  I looked, I pondered, I checked, & I uttered unpure words.  I finally discovered that one of the drive belts (the 12x36 has 2 drive belts) was a slight bit looser than the other one and actually flopped about when running.  I removed the flopping belt and the vibration was cut down by at least 2/3.  Better, but not good enough.  So, I put the level back into position, and started fiddling with the 4 feet.  I found that I could make very small changes in the feet without much change in the actual leveling of the machine--(kind of like changing the preload).  So, I messed with it for quite a while until I was able to get the majority of the shake out while still maintaining very close to level across the ways.  This may not prove of any value to your situation, but then--Who knows?  Stranger things have happened.  Here is a pic of the feet I used.  BTW, I have these on both my Lathe & Mill (PM932PDF), and my previous Mill in Alaska--Absolutely no complaints about the feet.

I hope you get it sorted out.
Jerry in Delaware


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## mksj (Jan 17, 2016)

I need to clarify, not filling the cabinet with concrete, if you look at the base there is a a 4.5 inch compartment between the base and the lower shelf. If you turn the cabinet upside down, sealed the seams, one could partly fill the bottom area which could add a significant amount of weight to the bases. The mounting feet bolts are not in this cavity, but one does need to give thought to anything you want to weld or bolt to the base. I believe the non threaded holes in the base will take a 5/8 or 3/4" bolt. These are what I use for my feet with opposing heavy washers and lock nuts. I have my cross base bolted to this area. I like what the individual did with his grizzly to widen the stance, which goes a big way to adding rigidity. Alternatively a steel plate between the bases. Just do not follow why the recent issues with vibration with the machine.

I would think that if you are using solid metal feet, and the machine is not bolted to the ground, that if the load is not properly set between all the feet that you could get significant rocking/vibration in the machine. If bolted to the ground, what I gather from Matt, is that the threaded holes are used to put an opposing load down against the mount to load each mounting bolt.

Mike and I both recommend starting with the stock motor, we have had no issues with it. The additional weight (maybe 30 pounds) and control with the Marathon motor, should not worsen a vibration issue. It is a much better motor, and inverter rated. It is rated to pull full torque down to 6Hz.  Another member that I worked with on his VFD conversion, installed the TEFC version of this motor (bigger space), it works wonderfully relative to the stock motor it replaced.


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## RIO (Jan 17, 2016)

Muskt: those are the exact leveling feet I got too, which are as far as I can tell the same as Mike and Mark are using, just a different brand. Mine are from Enco.  One question for all of you:  are you putting the lock nut on top of the stand plate, or under?  Probably would help to buy four more and do both, top and bottom.
I actually want to install much bigger levelers in the other 3/4" holes to see if that helps.

Still pondering the next move on this issue....man, I wish I could drill my floor.....


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## Steve Shannon (Jan 18, 2016)

Rather than drilling your floor, you might be able to epoxy plates to your floor with studs welded on them. If the area of the plate is sufficient it will hold as well.


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## Duker (Jan 18, 2016)

I made a cast concrete base for a fellow woodworkers new Powermatic lathe.  While the goal was to create mass it was more so to have a very stable base at the right working height that would accommodate his wheel chair. I made a rough concrete form from 2 x 10's and then added threaded j rod in which I bolted down a 2" x 2" shot filled frame in which the lathe then bolted down into plugs I welded into the tube. It was very solid even when turning a large very off center bowl blank. It took me a weekend to build the forms and cast the base and another to weld up the frame.  I am not sure what it weighed but it certainly pushed the limits of the rented gantry I used to load and unload from the trailer.  

This type of base could give you the mass that Mark recommends without the risk of drilling into your floor.  Perhaps you could cut the existing metal base down weld a mounting plate and bolt it to a cast base to get the height you need. 


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## zmotorsports (Jan 18, 2016)

I know I posted above what feet I am using but don't recall if I mentioned, but I have not had any issues with vibrations.  In at least one of my videos, possibly more, I show and mention just how smooth my lathe is.  I am very happy with the finish it produces.

That said, I am going to be adding some weight to the base, but not due to any adverse issues, I am merely looking for some more tooling storage and the filler panel area seems like a lot of wasted space.  I will be removing that and adding a toolbox/roll cabinet attached to the two outer side cabinets.  This should allow me to store more tooling as well as a little weight as a side benefit.

I hope to be caught up on jobs in the next month or two that I can get going on that.

Mike.


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## RIO (Jan 18, 2016)

Steve, epoxying a plate would probably help, I don't know how much.  Good idea though.

Duker:  if not too inconvenient, can you post pictures of the super-stand you built?


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## mksj (Jan 18, 2016)

Made a video of my PM1340GT lathe vibration stability vs. speed. I think mass loading the bases and some bracing may go a long ways to enhance stability, I have about 200Lbs on shelving between the lathe cabinets.  You could do a larger steel perimeter base frame with rectangular steel (2x6 or something like that) and weld some studs or threaded inserts for mounting the cabinets to. I would then pour cement into the rectangular steel tube or you could make a bottom plate and pour cement into the center of that. 

Probably a matter of fine tuning of the feet, but no machine in this weight class is going to be rock solid. Bolting to the foundation should make a significant improvement, but that is not always an option.


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## davidpbest (Jan 18, 2016)

That's one heck of a chuck and brake time.  !!!!


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## qualitymachinetools (Jan 18, 2016)

I've also seen setups kind of as described, with a larger steel plate that is right about the depth and width of the cabinets, you could either tap or weld a stud in to that plate to bolt it down. You dont want to just set the plate on the floor though, you would want to epoxy it or something like that like Steve mentioned. You can get a piece of 1" Plate pretty reasonably.
   That would be about second best to bolting it down directly to the floor. Must be one heck of a nice shop with the radiant floor heat!

Adding some weight to it I am sure would help too. But try out the machine first before getting too much in to any of this.

The idea of a cast base is a good one, but it would be a lot more than a $500 option on this machine. I've already looked at that, and it is just not practical, at least not from what I could come up with pricing. And at that point, you are up to the next model in pricing.
  And we have hundreds of these machines out there (Soon to be thousands), and these are the only comments I've ever heard about this issue is these couple in the last week or 2. Same with machines like the Sharp 1340VS and many others. That machine also does not have a cast iron base, it has the same type as the PM-1340GT. Same with the Hardinge HLVH, most older Clausing lathes in this size range just to compare. This is not a 4,000 pound lathe, but it cuts just fine how it is, and will handle exactly what you want to do just fine. Of course it is best to bolt it down as it is designed, but most people do not want to do that, so they use other methods and it works great for them.

  I've ran lathes that were huge and had their own foundation poured for them, and even they were bolted down.

 Marks video is great though, he has an amazing setup on his machine, no question about that.


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## zmotorsports (Jan 18, 2016)

I would agree with Matt and run it before over thinking it.  I have had mine for coming up on two years now and it is still just as smooth at when I first set it up.  I have had an odd shape peice throw it off a bit but that is only on rare occassions.

Mike.


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## sanddan (Jan 18, 2016)

I am using the same feet as shown above, it looks like only one person that has posted here used something else (mason feet). No one seems to have bolted to the floor yet so it is hard to know if it makes a big difference or not. Who is going to be the first?  LOL


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## sanddan (Jan 18, 2016)

zmotorsports said:


> I would agree with Matt and run it before over thinking it.  I have had mine for coming up on two years now and it is still just as smooth at when I first set it up.  I have had an odd shape peice throw it off a bit but that is only on rare occassions.
> 
> Mike.



Mike,

If my lathe ran smooth I'd be as happy as you are. My bad luck I guess.


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## mksj (Jan 18, 2016)

Did you run your lathe with the PM 3J chuck that came with the machine? The machine is pretty lightweight, any imbalance in the chuck will cause the vibrations you noted, if not worse. I had Chicom 4J and anything past 230RPM caused intolerable shaking, the new Taiwanese 4J independent I have no problems. I swing my Bison 8" up to 1600 RPM with no significant vibration, you always get some vibration nodes. The machine just doesn't have enough overall weight to damp out poor chucks that are either out of balance or not running true. Bolting it down in my garage is not an option, but I did mass load the stand which helped.


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## RIO (Jan 18, 2016)

sanddan said:


> I am using the same feet as shown above, it looks like only one person that has posted here used something else (mason feet). No one seems to have bolted to the floor yet so it is hard to know if it makes a big difference or not. *Who is going to be the first?*  LOL




*ME*.  I just did it:









Guess what.....didn't fix the vibration.
The one improvement is that with opposing anchors, it makes it real easy to level out the bed, and take out any bed twist (which is almost none with this machine already).

I'm now focusing in on the top where the lathe bolts to the stand.  Check out this picture and the yellow text and arrows:







What I'm noticing is that if you have a well-balanced machine to start with, the lack of stability in the stand setup doesn't matter.  I think for some reason, Mark's (MKSJ) machine seems to be much better balanced than mine.  I tried running it with nothing but the dead center installed in the headstock, then put the Taiwan (PM) 4J chuck on.  Same results with either.
Could the Bison be what's making Mark's machine run so smooth??


RIO


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## Muskt (Jan 18, 2016)

Hey RIO--I can't tell from the pic, but does that machine have 2 drive belts?  My 12x36 does, & removing one made a huge difference in my vibrations.
Jerry in Delaware


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## RIO (Jan 18, 2016)

One belt.  I'm running this one:
http://www.amazon.com/Gates-Tri-Power-Section-Outside-Circumference/dp/B00CJJCZSA

I think Mark is running the BX25.  Bigger could be better.

My stock pulley on the driven end is also out of true, or has a runout of .005.  Could be causing some of the shake too.  I'm thinking about replacing that.

Mark, where did you buy that Bison 4J?  That might be my next step.

Uploading a youtube video for you guys tonight....


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## Steve Shannon (Jan 18, 2016)

That's really smooth. 


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## Duker (Jan 18, 2016)

RIO said:


> Duker:  if not too inconvenient, can you post pictures of the super-stand you built?



Rio, i don't know if I would call it super but it did the job.   I thought I had some on my iPad but I may have saved them to my laptop. If I find one I will post it up. 


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## mksj (Jan 18, 2016)

Rio,
I have a BX-24 for the low speed BX-25 for the high speed pulleys, shouldn't make a difference. The run out in the pulleys is minor, the pulleys would have to be significantly off to cause significant vibration. I doubt it is the drive train. I do not have a problem with any of my chucks, so something else is going on here, but this is what I am using:
Bison 7-848-0800 - 8" 4-Jaw Plain Back Combination Chuck (Scroll plus and Independent) Poland, I machined the D1-4 backing plate on the machine to fit this chuck. Probably my favorite chuck, takes no time to 0 the TIR, but if I have a lot of repeat machining I use the PBA. This chuck is considered more of a fringe product, and is costly. I bought it when I did not have a 4J independent, I do a lot of repeat turning on odd size metal.
Pratt Burnerd America 0625300 - 6" 3 Jaw Setrite Chuck (Sroll) UK with a PBA Setrite D1-4 backing plate, really nice chuck, Bill has the 8" and swings his up to the machine max RPM.
Precision Matthews - 8" 4 jaw (independent) Taiwanese D1-4,  Really nice clean casting and machining, even has balance weights on the inside of my chuck, it is right up there with the Bison and the PBA in quality.
LatheMaster 5C Collet D1-4 Tru-Setting

The first three chucks, I can recommend, the LatheMaster 5C less so, you can dial in the TIR to near 0, but the chuck body wobbled and I had to turn the body true. My runout at 6" from the chuck with the PBA and Bison is well under 0.001", the LatehMaster is under 0.002" for what it is worth. My experience so far with the Chinese chucks, is that they make good doorstops, that's about it. These days Grizzly is probably the best option for PBA and Bision, QMT also carries Bison. If Grizzly, I purchased my PBA from them using a discount code.  The Bison dealer I purchased the Bison combo from is out of business.  They have gone up about 20% since  I purchased mine.

Nobody has mentioned if the Hz display is staying stable, it should not flicker or change at all with the programming settings I have posted, nor if either Dan or Rio are seeing vibration with just the motor alone spinning. I wanted to rule out that maybe the motor support is not locked down or moving causing the belt to flutter/vibrate.  The splash pan is thin steel, it twists up a bit when mounted ( have the same thing on mine), what really counts is where the lathe is bolted too, ant his should be absolutely rigid with no rocking trying to move the machine back and forth. . If you do pull your lathe off the cabinet, you might check if there is any warpage in the cabinet where the lathe mounts, the other consideration is accurate leveling with a precision level.  This may just be cabinet flex or the lathe is not sitting level on the cabinets, I have my cabinets tied together at the top and bottom, the chucks set on the lower shelf, metal on the upper. About 200Lbs on the shelves another 100Lb in the cabinets.

Maybe go out buy some sand bags and put them on the bottom of the cabinets and see if that does anything for you.  I do not have anything further to suggest beyond what has already been mentioned. I am sorry guys, but I am going to bow out at this point, I am pretty new to this stuff and there are more seasoned machinist that have a lot more experience and can provide better guidance.
Mark


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## RIO (Jan 19, 2016)

Next test:  I just dialed in (with a Mitoyo .0005 indicator) a Krieger 26 inch match barrel blank through the headstock to absolutely running perfectly true in the four jaw and the spider, then ran the machine.
Whatever is out of balance reveals itself most-pronounced in high range and high gear at 40hz.  The entire machine is shaking, the work light, the DRO, and literally the whole headstock - SHAKING.  Wait until you see the video tomorrow.

Something is just badly out of balance.  Yes, if it was bolted to a 3000 lb stand bolted to the center of the Earth, one might not notice the shake, but the ROOT of the problem is something is running badly out of balance.  What a disappointment.  Wish I would just find out I'm doing something wrong and it's not the PRECISION Matthews lathe I just paid a premium for that's the problem, or this "high precision", Preferred-package 4J chuck that might be the problem.  But, I ran the machine with nothing but the dead center in the headstock, and it still shakes.  Even with it bolted to the floor.

I hope somehow I did something wrong, and I can find out and fix it.  Otherwise, I got a lemon.
Sounds like SANDDAN might be in the same boat.

Too far down the rabbit hole, too many hours, too much money to turn back now....What's next?  Matt?


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## RIO (Jan 19, 2016)

Here's the video:


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## davidpbest (Jan 19, 2016)

I'd love to see the pulley & belt side of the machine in a second video running through the same tests.   What I'd like to see is how the belt is tracking and flapping.   Any chance you'd do another one? (he asks with hands over ears).  Also, what happens if you take it out of gear (between gear positions) such that the drive shaft is turning, but the headstock is not?

David


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## Rich V (Jan 19, 2016)

The fact that it kept shaking after you stopped the spindle leads me to believe the lathe is not well anchored to the chip pan/cabinets. If you give the head stock a hard push does the lathe continue to vibrate? If so then hunt down where it's flexing and see if you can tighten or shim it to give a tight setup.


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## RIO (Jan 19, 2016)

Rich,
Good insight.  All it takes is a really light bump with the palm of the hand to the headstock, and it visibly shakes for about 15-20 seconds.
See my post earlier with a picture with yellow writings and arrows.  I'm thinking of putting a solid 1/2 inch metal plate under the chip pan, the entire size of the chip pan itself.
Still something is out of balance in the gearhead of the machine, which is the root problem.


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## qualitymachinetools (Jan 19, 2016)

I second Davids suggestion. Also, post a video without the chuck on. Or with it just in between gears so the chuck is not turning. 
   I am betting that it is either the top/larger pulley, as it is is cast iron, or settings with the VFD, or a combination. Just had a conversation with someone at the factory, and they say to replace that top cast pulley with a fully machined pulley since you put the VFD on. They also said be sure not to go above 60HZ on the motor settings, because the stock setup and motor only go that fast. 
 I don't have a problem with a little faster than that, but that is up to you guys. Just don't run it at 400HZ and tell me the headstock is getting hot and the 4 jaw chuck flew apart. 

 And good point Rich, but Rio that drawing you made about the fulcrum is outside of where the lathe bolts down though.    Maybe get someone to push on it and look at the machine. See where its moving. 

 If there is a problem with the machine, it WILL be taken care of. But just remember, I don't build them, I am not a magician or a mind reader that can tell you in an email what it is.

 But whatever the problem is, I am here to help figure it out and get it taken care of. The hardest part is that these both have VFD's on them, so that part of it changed from the factory, so there are just a few extra variables in it. But if it ends up being a VFD related issue, I am billing everyone for the time I am spending trying to figure this out (Kidding, it will be good knowledge for future customers)

  - This is sort of how I can not for the life of me figure out how when I plug my phone in to charge in my truck, the radio goes to static, but only when I am not moving. When I am driving, it is OK. But when stopped, static. Unplug the phone, and it goes away. 

 I do wish that I could see it in person to get an idea of the shake though. Because from me looking at it in the videos, it is about 1/10th of what I was first thinking we are chasing down. But it is so hard to tell in a video if its a lot worse than I am thinking, or if its a lot less than is being described, compared with what is in my head. I remember back when I was 18 years old, guys at work running the Warner Swasey Lathes and having their Coffee sitting on the headstock. I never thought to look in the cup to see if there were ripples, but I do remember that they wanted to run jobs on the newer square headstock machine so the coffee cup didn't fall off. And they were all stained had a permanent coffee/cigarette smell baked in to them.

 I do feel like that if I was there in person, I could almost look at it and tell if its the pulley or not though. But it sure sounds like it is to me.

 But I agree with the factories suggestion, to use a completely different pulley. They do use a different pulley (Fully Machined) with our larger models that come with a factory VFD. (See picture included)

 I asked Dan about it and he said it is as cast inside, and told him feel free to true it up on his other lathe if he wanted to try that, I have another one coming to him anyway. I am not sure if that was done though.

 But as the factory suggested, use a different pulley, not the factory pulley for a setup that has been changed to a VFD controlled machine. 

 And Lafe, you did not waste time bolting that machine to the floor, like you said it is a lot easier to level, but it does make a difference. But you have not cut with your machine yet, so you may not notice as much.   You can mess around with that later on to appreciate it more
	

		
			
		

		
	







	

		
			
		

		
	
 .


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## mksj (Jan 19, 2016)

I was going to bow out of this, but there is one major factor that is being missed in all this. Rio run the video with the gear train disengaged. This is the feed direction knob on the gearhead must be in the center position. You have your machine with the gear train engaged which significantly increase the rotating mass and components in the drive system and vibration nodes. So the whole drive train is turning even though your gearbox feed selector is not engaged. If I run my machine as you have your setup, it is guaranteed to have vibration nodes at specific speeds and it gets noisy with speed, as this is an open gearbox. You can also hear the open gearbox drive gears ringing.  My machine will run exactly like your machine and shake at specific speeds, there are just too many gears with different masses going in different directions. I just avoid the nodes, or switch gears and adjust the VFD speed. It has never been an issue with getting a clean cutting finish. You would need every gear and component in the gearbox machined to high tolerance and in perfect  balanced and a much heavier lathe to dampen some of the vibration. Even then, all machines have vibration nodes at certain frequencies, this is specifically why VFDs are setup with skip frequencies. Every rotating system will have nodes, when running a VFD, you can always find a speed that will excite a vibration node for that system.






My machine will have similar vibration nodes just like yours if run with the feed direction engaged, but if you disengage the gear direction train feed, that will tell you if the drive and spindle system are running true. Looking at the light shake is not relevant, it is bolted to thin sheet metal on the back and it has it's own resonant frequency, I beefed up my mounting so it wouldn't shake so much.  With the feed drive and gearbox spinning, you just will get vibration nodes, this also explains the change one would see with the different pulley ratios. Different masses in the system will affect those nodes, my 60Lb chuck has more mass that decreases some of the vibration through gyroscopic affect. Also placing a water cup on top of the head, is where the vibration would be the worse, if you put it on the carriage, where your cutter is, I doubt it will barely move if at all.

Getting the correct belt tension is often critical, if the belt is too tight it will vibrate, especially if you are using the full weight of the motor to tension the belt. Run it slightly loose, but so the belt dose not flop or vibrate with speed. With the gear feed direction engaged, getting the right spacing between the large and small drive gear is also critical. If I recall it is suppose to be about 0.004" or the thickness of a piece of paper. Without the belt cover on, it makes a big racket.

Please rerun your video with your directional gear feed not engaged. Just the spindle turning, not the gear train drive. Make sure you are running sensorless vector and you autotune your motor (especially Rio, because your motor properties are different). If you want me to walk through any of the VFD setting, give me a call.

Rio, you did a real nice job on your VFD install, looks really good.

Mark


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## sanddan (Jan 19, 2016)

Rio,

This is the same vibration I am seeing. I have run many many tests trying to isolate the source of the vibration, it is in the motor/pulley or input shaft. Some of this is in my other thread   http://www.hobby-machinist.com/threads/question-on-aligning-the-lathe-spindle-and-bed-twist.41864/ . As rotating mass is removed the magnitude of the felt vibration goes down but the vibration is still present. The motor by itself runs smooth, either with or without the motor pulley. It is not normal, my Chinese Enco 12x36 lathe does not have a felt vibration at any speed. This is with either the 3 jaw or 4 jaw chuck. It is still running the belts that came from the factory 3 years ago. It is a single phase 2hp motor running a dual belt setup.

Matt,

The upper pulley is as cast, the only machined surface is the bore and keyway. I am pretty sure it is die cast as runout is pretty good, max I measured was .004" and that was on the surface the belt runs on. I haven't tried truing the pulley as I have to machine a mandrel first to keep it concentric with the bore and my other lathe is down. I was focused on improving the stand rather than bolting to the floor , seeing that bolting might not fix the issue I could go back to working on the pulley.

Mark,

You made a comment about the cup of water in the video being on the headstock and maybe not feeling it on the carriage. Other than doing the break in procedure, the first time I ran the lathe was to machine the test bar as part of the headstock alignment and that's when I first felt the vibration. I had my hands resting on the carriage cranks and felt the shake. That led me to looking closer and seeing that it was worse on the headstock. I have run my other lathe enough that I immediately the difference. The carriage has less felt vibration than the headstock but it is very noticeable non the less as you are feeling it through your hands. It is hard to show something like this on a video thus the cup of liquid.


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## RIO (Jan 20, 2016)

As requested:


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## Muskt (Jan 20, 2016)

Looks as though the mystery is lessening.

A few things jump out to me:
1.  I do not like that belt flopping about like it does.  It doesn't seem to be tight enough, and it doesn't fit the motor pulley very well (Opinions only--I'm certainly not an expert).  A flopping belt will have a harmonic (similar to what you are experiencing).  The one loose belt on my 12x36 really caused a vibration--even worse than what you are experiencing.  Removing the offending belt really helped.  I understand that yours only has one belt, but it really flops around.
2  I had a chuck problem on my previous 9x20 in Alaska.  It was a 6 inch 4 Jaw.  The jaws were different lengths; therefore, different weights.  They varied by up to 0.070--This caused the vibration to increase as larger items were chucked up.  I should have exchanged the chuck, but did not (Silly Me).
3.  You never mentioned (Or I missed it) that you had run the motor with no belt on to determine if the motor might be unbalanced.
4.  Are you ABSOLUTELY certain that there is not any junk between the lathe & the base cabinets, or is the bottom of the lathe actually smooth--IE no casting imperfections (bumps or ridges) that may cause the lathe not to sit solidly on the base?

These are just random thoughts, and not intended to be criticisms--moreso additional things to check.

Hope you get it figured.
Jerry in Delaware


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## joshua43214 (Jan 20, 2016)

RIO said:


> As requested:



I think your second vid is the most informative so far. I wish you had put your hand on things to stop the noise. The doors on these stands are a bit junky, might just be the door rattling? Adjust the lever on the back to make it fit tighter.
I can hit my head stock with the palm of my hand hard enough for it to sting and it just goes "thump." My lathe is just sitting on the adjustment feet it came with.

It sounds to me like the lathe is just not getting a good bed on the stand. I would pull the lathe off the stand and make sure the mating surfaces are flat and free of debris. It is important that the pillars are coplanar as well. I wonder if one of the pillars is leaning at an angle, and the center support is preventing them from being pulled up tight to the bottom of the lathe.
Level the base, install the lathe, level the lathe, tighten the center panel. That way the center panel will not interfere with the base alignment.
You can get heavy gasket paper from NAPA that will make an excellent bed between the lathe and stand. I don't advocate using silicone sealant - it does nothing to bed the lathe, and makes taking it apart a hassle.


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## Rich V (Jan 20, 2016)

That long vibration after bumping the head stock by hand is at least part of your problem. Can you see where the rocking point (pivot point) is when it's vibrating? It could be that you don't have a good flat mating surface between the lathe and the chip pan/bench top. It's also possible that the chuck is slightly out of balance and combined with that long vibration you have it doesn't take a lot to get it vibrating at certain harmonic nodes.

If it was me I would find where that rocking from a hand bump is an correct the cause. That may be you main problem


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## planeflyer21 (Jan 20, 2016)

Rio, your post #28 shows there seems to be quite a bit of space between the pan and the base.  IMO that is the culprit of the rattling sound.  Either the pan needs to be flattened or shimmed to get a better fit with the base.

As to the belt, IMO that is a contributing factor as well:  a kind of stacking of tolerances if you will.  I had a machine that came with a V-belt that left rubber bits everywhere.  Replaced that with a good Goodyear V-belt and was in heaven.  Replaced that and the pulleys with the poly round belt style and was in 7th heaven.

IMO in order of fixing, 1-pan to base fit, 2-new belt.


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## zmotorsports (Jan 20, 2016)

I just went out and ran mine again and looked closer at my chip pan and I agree with the two above that the chip pan/cabinet/hard mount is definetily something that needs further investigation.  Look closely at where the holes are drilled and see if one of the holes in the cabinet have the center pulled up which would create a high point.  If memory serves I ran a chamfering bit around all of mine before assembling.

My stand/lathe setup is rock solid and I can hit it quite hard with my hand and there is no sound but a dull thud and a sore hand.  I also noted quite a difference when I replaced the original belt with a better quality one upon the first hour or so of running the lathe.  I too would investigate the chip pan first followed closely by the v-belt.

Mike.


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## sanddan (Jan 21, 2016)

zmotorsports said:


> I just went out and ran mine again and looked closer at my chip pan and I agree with the two above that the chip pan/cabinet/hard mount is definetily something that needs further investigation.  Look closely at where the holes are drilled and see if one of the holes in the cabinet have the center pulled up which would create a high point.  If memory serves I ran a chamfering bit around all of mine before assembling.
> 
> My stand/lathe setup is rock solid and I can hit it quite hard with my hand and there is no sound but a dull thud and a sore hand.  I also noted quite a difference when I replaced the original belt with a better quality one upon the first hour or so of running the lathe.  I too would investigate the chip pan first followed closely by the v-belt.
> 
> Mike.



Mike,

Could you check the underside of your stand and let me know if it looks like mine? I am referring to the mount the lathe bolts to (see attached pic).

Thanks
Dan


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## zmotorsports (Jan 21, 2016)

sanddan said:


> Mike,
> 
> Could you check the underside of your stand and let me know if it looks like mine? I am referring to the mount the lathe bolts to (see attached pic).
> 
> ...



Dan, is that sealant/RTV on the underside of the bolts/washers?

Mike.


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## mksj (Jan 21, 2016)

Dan, my lathe cabinet underside looks the same as yours. My drip pan also bows up a bit at the edge of the cabinets. Probably doesn't vibrate because I used some RTV when bolting up everything.





Gates Tri-Power cogged belts.  I have both the BX-24 and BX-25. Interestingly the Gates BX-24 has a slightly bigger diameter than the stock B-25. The BX-24 was a little difficult to get off the pulley to change speeds, but that was when it was new. So I am running the BX-25 one on my low speed pulleys for a top end of 1200 RPM at 90Hz. The BX-25 was too long for the high speed pulley set, so the BX-24 is the one I would recommend or get one of each at $6 a piece. It runs much more smoothly, but I do notice the belts will take a set if the lathe is not used for a while. It smooths out after a couple of minutes of use.   Changing the belt quieted things down quite a bit, and the stock belt seemed to be throwing a lot of rubber bits all over the belt cover.

Royal Supply has a wide selection of belts, pulleys, etc., there is also SDP/SI when I was looking into pulleys and couplings for CNC.
http://www.royalsupply.com/store/pc/Gates-BX24-Tri-Power-V-Belt-9013-2024-1095p36411.htm
http://www.sdp-si.com/index.asp


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## sanddan (Jan 21, 2016)

zmotorsports said:


> Dan, is that sealant/RTV on the underside of the bolts/washers?
> 
> Mike.



Yes. I didn't on my other lathe and wish I had as that one leaks somewhere by the motor and ends up on the floor as it seeps through. I squirted it up into the hole after the bolt was inserted but before the nut was tightened.


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## zmotorsports (Jan 21, 2016)

Dan, mine is mounted the exact same way.






I didn't use any RTV on mine but I did chamfer all bolt holes as they appeared to be punched rather than drilled and I noticed one looked a bit convex so I did them all.

I wonder if that could be part of RIO's issue, the bolt holes aren't allowing the lathe to bed down onto the cabinets properly.

Mike.


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## sanddan (Jan 21, 2016)

I asked about the underside of the cabinet as I can feel the plates flex. If I hit the headstock similar to Reo's video I get a similar "ring" but not as bad. That got me looking for any gaps which I didn't see. I did notice how the underside of the cabinet was made, the weight of the headstock is out on the unsupported edge of the 2 plates. On my machine if I put my right hand on the plates and push on the top edge of the headstock with my left I can feel the plates flex. Easy solution, just requires me to do a lot of disassembly but it's just time and some steel.


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## RIO (Jan 22, 2016)

Boys, I'm sorry for the silent delays.  If I told you how crazy life is right now....nevermind.
Dan, et al, sorry I'm not replying to all you guys individually each time.  You all are giving such great inputs, I just don't have time to reply.

Quick summary, then I have to get back to domestic duties:

1.) I realized that since I installed the Marathon motor, and had to buy a new drive pulley because it was 7/8" shaft, that I mis-matched sizes.  I was running a Gates AX-25 because I got an AK series drive pulley, but the stock "driven" step pulley is B series.  I just ordered a BX-25 belt and  a new B series drive pulley for the motor (should have listened to Mark/Mike closer in the first place).  When I get this new belt/pulley setup fixed this week so everything matches in size, I'll post pictures.  Might make a big difference.

2.)  I ordered a 1/2" steel plate, 15" x 66" to put between the chip pan and the stand.  It will be a small chore just to drill the six bolt holes and the drain hole.  I expect this plate install to really help, if not mostly fix the vibration.  Dan, your inputs and insight on the issue with where the lathe bolts up to the stand confirmed what I was already thinking, and helped me decide to do this.  In fact, I remember emailing Matt to address that issue a few days ago.  Basically, I said "I think it might help a lot if that was one solid piece of steel across the top of the stand where the lathe bolts down to each section".  I'm doing that and more by putting this [$70] steel plate all the way across the top under the chip pan.  Can't wait to see what changes.

3.) I hooked up an A/C reactor in line on the load side.  Couldn't help it, I was curious to see what it did.  Mark advised me awhile back that it probably wouldn't help anything.  He was right.  I ran the motor, and noticed no change.  Curiosity satisfied, I'm returning it.

I'm happy that for Mark, Mike and others that they got a stable setup first try.  But for guys like Dan and I, it highlights a need to make some factory changes to this stand setup, because it seems to be about a 50/50 chance that the setup will work well the first try.  And bolting it down still doesn't fix the problem, as I realized.  I bet we really see Matt engage the issue with the factory in time to come.  That's what we've all come to see and expect from him.  In spite of the painful issues we're having, I think he's earning all our trust and customer loyalty.

Oh, by the way, Dan, mine looks just like yours too, where it bolts down to the stand.  And I didn't use RTV or anything.  Thought about that later, and probably will use that or silicone this time when I re-do the mounting, so I don't get cutting fluid leakage.

One more thing:  I ordered all my belts/pulleys from Amazon.  With amazon prime, it was cheaper than royal supply, after they added shipping.

More to come.
Thanks for all the input and help.  Hope my (and Dan's) growing pains help somebody else in the future.
RIO


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## mksj (Jan 23, 2016)

Rio et al,

I tried to look at what would be considered the resonant frequency of the system on my Pm1340 lathe, and also compare different chucks to see if it is a balance issue. I dialed up some  1" stock in the  8" QMT 4J independent chuck, measured the chuck run out and ran it carefully form 10-90 Hz, I also repeated it with my Bison 8" combo 4J which is about twice the weight. I had previously mentioned that the new Taiwanese QMT 4J was a significant improvement, and when I tried to measure the TIR of the chuck body with it mounted on the lathe  it was under 0.0001", I actually did a double take because the dial indicator looked like it wasn't moving. Much lower TIR on the body than any of my other chucks. I then ran the lathe and could get some small vibration at ~620 RPM (~45.2 Hz in high gear low speed belt ratio) and around 1230 RPM. I reran the lathe with the Bison, and I encountered the same two resonant points within a few RPM. It was independent of gearing and also if I had the feed engaged or not. It did not change. The total resonant band was maybe 20-30 RPM, on either side this machine was absolutely smooth. Without the chucks, I really could not see or feel any resonant frequency no matter what I tried. So these are most likely the resonant frequency nodes for my lathe with the additional weight of the chucks, and normally one would not be seen these in the non-VFD version because they do not align with any of the 60Hz speed ranges. It was also interesting that it did not change with different chucks.  The vibration nodes may not be the lathe per se, but the resonant point of the cabinets and flexing where it is mounted to the top of the cabinets or between the cabinets.

There is one other possibility which has to do with an oscillation between the belt vibration and the mass of the chuck. Looking at your video, you can see the belt walking back and forth (wobble) on the pulleys, and up and down in the grove. The pulleys look like they are running without any wobble, and the TIR reported was fine, which would indicate that the pulleys are running true. 

Having a more rigid mounting base, should go a long way to preventing any flex, and it might be a bit more noticeable on your lathe because of the additional motor mass hanging off the back.  But it did not appear to be chuck,  gear or feed dependent on my machine.  I think it is worthwhile to note that there is always resonant frequencies, nodes that mechanical systems will vibrate, this is a big issue with VFD drive systems. Regarding  the new Taiwanese QMT 4J, I am impressed with its quality, the casting/finish,  jaws and mechanics are top notch (world of difference from my Chinese one). I do not feel this is a factor in this issue, but try different chucks. Look forward to your update.

Agree, with you on Royal supply shipping costs, and I had to do a second order for the larger size belts . The belts are cheap relative to the packing/shipping costs of most vendors, so you do need to shop around.
Mark


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## qualitymachinetools (Jan 23, 2016)

Hey guys, I have been quiet on here for a bit, but I have been looking hard in to some options. Mostly different pulleys today, but looking at the stands too. It is tough, these 2 are the only issues that anyone has ever really brought up about them, but I am always open to improvements. Especially with something as easy as that. 

 I am still curious though where that 15 second rattle ( or whatever you would call that) is when the machine is not running. Something has some sort of tension on it and is not sitting right somewhere. There are 4 bolts holding the headstock end down and 2 on the tailstock end, So that should not be it. Its almost like there is some sort of tension somewhere, I am not even sure how to describe it. Try some wooden wedges under all of the cabinet corners real quick, just tapped in a little bit to tighten it up, if you have some scrap wood and a saw laying around, to see if that gets rid of that vibrating in that video. That steel plate is a good idea, but what its doing should not be happening without that plate.     Can you see whats shaking on that when that happens? Something is different there, none have ever done anything like that before.

 The little bit of shake at a certain speed with the VFD on is one thing, but that rattle is another. Check the welds in the stand on that top plate, it almost seems like one is broken or missed where those top pieces go on if thats where it is coming from. 

 The good news is that for how smooth its running without a chuck, I wouldn't do too much more with that. The only issue it is moving when you push on it. 

  Just have to find that rattle and you will be set.   

 I will have more to post as I have any updates on things. Always trying to improve things, if there is a problem with anything, I try to eliminate it.


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## qualitymachinetools (Jan 23, 2016)

Great post Mark, that must have been posted after I started typing the last one. (Started at 8am and finally posted after 5!)


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## stevemetsch (Jan 23, 2016)

I run the supplied bolts down the threaded holes to level the lathe, then went around and balanced the torque on each front/back pair. Lathe is solid. Heavy steel plate epoxied to a CLEAN concrete floor will do a good job of replacing drliled anchors.
Steve Metsch in dry Santa Barbara.


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## joshua43214 (Jan 23, 2016)

@qualitymachinetools 
Matt,
I will bet you almost anything that when they assemble the stands, they are not making sure the punch-outs are facing down.
If the top support plates is flipped over after being punched, it will result in the lathe not bedding down to the firmly. It will be sitting on a little hill around each bolt hole. Simple enough to fix with a ball peen hammer if one is looking for it.

Might no be so easy to get them to put them in right though. Hard enough to get factories in the west to face washers or snap rings the correct way...


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## sanddan (Jan 24, 2016)

Matt,

The primary improvement to the stand that I would suggest is to make the mount plate on the top of the column one piece instead of 2 piece. The weight of the lathe is on the unsupported edge allowing it to flex. The "ring" Reo and I get could very will be as you suggest, a raised area around the holes. I will look for that when I pull the lathe off the stand. I ordered up two 1/2" thick plates that I will add to the top of the columns, this will eliminate the flex. I'll also deburr the holes before installing them. Reo's solution of a one piece plate is also a good solution. The stand on my other lathe is also sheetmetal construction but the top is one piece, not 2 piece. It is only made out of the same thickness material as the rest of the stand but doesn't seem to flex at all. Hitting the top of the headstock only gives a dull thud, much like zmotorsports described. The rest of the stand is pretty crappy, no shelves for storage or even a bottom plate. Getting the flex out of my setup is the goal at this point, hopefully that will solve the shake issue.

For you tech geeks, here is a screen shot of an FEA analysis of the 2 piece mount plate. It's anchored on three edges and a load of 440lbs applied over an area simulating the lathe casting. The screen shot shows the deflection, the scale is magnified as the max deflection is about .010". Note the deflection near the bolt holes is about .004".




Modeling a one piece plate give about .002" deflection near the bolt holes. This is a good way to compare 2 different designs but keep in mind it is still a crude estimate of the actual system as it ignores the clamp force of the bolts. Also it is a static analysis just using the weight of the lathe for inputs. Still is shows that the one piece design is much stiffer.


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## RIO (Jan 30, 2016)

BEFORE MIDNIGHT VIDEO:








AFTER MIDNIGHT VIDEO:


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## sanddan (Jan 30, 2016)

Congratulations RIO! After watching the first video I felt very bad for you (and me) as it sounded like my plans weren't going to work either but the second video showing success is very encouraging. I have been convinced that the stand is the main problem with the shimmy and ringing we have been experiencing. I started along a similar path of reinforcing the stand but after thinking on it I decided to go a different direction. I am building a completely new stand using 2x2 tubing and incorporating a 44" HF tool box for storage. After seeing your results I think I'll add a feature that will allow me to bolt to the floor if I have to. Thanks very much for sharing the videos.


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## RIO (Jan 30, 2016)

Dan, I think that is the ultimate idea for this PM-1340GT!  Build a REAL stand, and you'll have the ultimate 1340GT.
Can't wait to see it.
RIO


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## mksj (Jan 30, 2016)

Hey Rio,
Seems like you and Dan are having a swaying motion type of vibration, interesting solution and thank you for working it out. I still think the upper plate will add rigidity to the structure, and seems like you have a very rigid set-up.  I always was puzzled about only two supports on the motor cabinet, that you could get a lot of flex between the cabinets. Since I added the 2" square tubing braces between the cabinets, I mat not see it as much. The bases are built to a price point, but I agree that a more rigid base goes a long way to getting the maximum performance out of the lathe. 

On the head stock alignment, would use a 0.0001" dial indicator to check the head alignment, then check at 0 and 6" with your test bar. I would the try the 4J and check the TIR at the chuck and then at ~6-8" out. As you can get some wobble with a chuck, I check that the wobble +/- around the 0 point is the same. Then you can do some test cuts with a two ring bar. Bed twist is more of a factor further away from the chuck, I set my machine up with a 0.0005"/foot precision level, running it the full length on the carriage travel. At 6" out from my chuck dialed in to better than 0.0001" at the chuck I get about 0.0004" total TIR at 6-8" out. This is similar to what Dan had. I then aligned the tailstock so it reads within 0.0002" of what I read at the chuck, looking that the sing is the same +/- around 0.  There is a point of chasing your tail with all this, when you just need to say it is good enough.
Mark


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## qualitymachinetools (Jan 31, 2016)

Great to see some good news!

 So I am thinking it is that bottom piece on the stand that is or was flexing, where the leveling pads are mounted in. 
 Dan maybe just do a setup like that to save a lot of time and money in building a different stand. Unless you already started it!
 Of course a nice stand with tool storage would be an excellent setup though, but just a lot of work!
 Glad to see some progress on this!


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## RIO (Feb 1, 2016)

So, I found another issue last night.  Actually, I think this one has been a major source of vibration the whole time.  I actually made this video for Matt at QMT so he could see the problem:







Second video:


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## mksj (Feb 1, 2016)

Rio, my machine belt tension bar is the same as yours, but my belt tension is a bit tighter. It has not been an issue, nor did I feel the motor vibrating when it is running. Probably even less of an issue on yours due to the motor weight. Agree it, I was a bit surprised at the play when I first noticed this, but hasn't been an issue. I may ultimately mill a new support or mill a bushing for the current support. If you did not want to remove the mounting bolt you may be able to slide a washer with a slot cur in it or use a SS lock washer by opening it and then compressing it around the bolt.


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## Muskt (Feb 1, 2016)

Rio, how about putting some (quite a bit of) downward tension on the motor and then tighten the lower bolt.  This should  A) Tighten the belt, & B) Allow the tension on the belt to prevent the motor from bouncing around causing vibrations.  Option 2 is to fix the arm.

Have you made any chips yet?  What type of material are you using?  If you can locate some, obtain some 12L14 steel and play with it.  It is amazing stuff to machine.  The CrapSteel sold in Lowes/Home Depot/TractorSupply/etc is generally horrible to machine.

Here is a link :  http://www.onlinemetals.com/merchant.cfm?pid=9561&step=4&showunits=inches&id=265&top_cat=197

I have purchased from this vendor previously and been very satisfied.

Good luck
Jerry in Delaware


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## qualitymachinetools (Feb 1, 2016)

Hey Rio, are you actually having a problem or did you just notice it was loose?  It wouldn't hurt for it to be tight, but I don't think it is doing anything is it?

 Start making some chips with the machine and post some videos of that!


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## RIO (Feb 2, 2016)

Fixed.  Big lock washer behind the bar/bushing screw on the top.  yes it was a problem.  Yes it made it better.  A LOT better.  Thanks for the help Mark.
Had to take the top pulley off to get the bushing screw out.  Had to bang the pulley off.  The key was way too tight.  Lop-sided actually.  Filed and sanded the key a little, and the pulley slides on and off the way it's supposed to now.
.  
"Just make some chips" is good advice if you own a potato chip factory, not if you bought a "high-precision gunsmith" metal lathe that did by no means came plug-and-play as advertised.  I've been very gracious and patient, and I appreciate Matt doing the same.  But for what I paid, I should have been chambering "high-precision" barrels by now.  If "chips" was my end product, I would have bought a Grizzly 

yes, still smiling....

P.S.  I made chips last night about 1:00.  So what it was PVC  
         I'm already addicted.  Going on 3 hours of sleep like some love-sick teenager...


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## qualitymachinetools (Feb 5, 2016)

HA HA its just a saying, but glad there is some good progress made here. I am working to try to have a cast iron base as an option for the machine, but striking out so far. (It can be done, but not at a reasonable price, yet anyway)   But we will see what happens. There is always room for improvement, just a matter of if people can realize the difference, and if they are willing to pay the extra cost for it.

 Looking at the 1340GT Lathe base though, I think that Rios method of leveling helped a great deal, I think that the shake he had was coming from that mounting bar on the bottom being right in the middle, it seems to flex there. 

 For example, Our PM-25MV is completely different than the similar sized machine that Grizzly has, and every single day I get calls and emails telling me that Grizzly has a lower price. It has different castings of a much better design, different motor, different drive, so much different on it. But every day, people insist that they are the same exact machine and that I need to match their price. A lot of people do see it, but a lot of them don't. 

But if/when the cast base for this 1340GT is available, you guys will be the first to know.


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## wrmiller (Feb 5, 2016)

I might be interested in a cast base Matt. Please put me on your "first to know" list.


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## AirWolf (Feb 6, 2016)

wrmiller said:


> I might be interested in a cast base Matt. Please put me on your "first to know" list.


 Yes... put me on the list too.... 
I am looking at the cavity at the lower base section Mark mentioned... possibly welding seams and installing some "warmed up" lead maybe?


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## mksj (Feb 6, 2016)

Mass loading with cement or sand is easy and cheap, or welding some 1/2" plate to the bottom and possibly  the top. The next step up would be to have cast iron cabinet shells which have both mass and inherent dampening capacity.  Many manufactures like the G4003G no longer offer this option in some of their machine bases for this size lathe. A full cast iron base would probably be almost as heavy as the lathe, seems like a point of diminishing return, as it has not been demonstrated that the machine's turning capacity is affected. As  previously mentioned, you can always find a vibration node of a system, add all the rigidity you want but in larger systems something else will break the more rigid it becomes.  This is a bigger issue with VFD/adjustable speed systems, doesn't matter how big or small. I have read postings on Grizzly machines and other brands that have had similar cabinet deflection, usually solved by some steel or adding base ballast and/or securing to the foundation.
http://bbs.homeshopmachinist.net/archive/index.php/t-64738.html
http://www.hobby-machinist.com/thre...t-as-described-should-i-send-this-back.28513/

There is a lot of good information at this point, most of which points to some deflection in the cabinet bases. Rio's solution was found after a lot of sweat and frustration, Kudos to Rio. It is a relatively simple solution, other individuals have weighted down the base bottoms and have had similar improvement in their machine stability. So for individuals already with machines, get some sandbags and put them on the lower shelf. According to someone else, about 200lb in the motor cabinet and 100lb in the tailstock end cabinet had a significant improvement in stability. I have seen this mentioned many times for this size lathe, long before I had my PM1340GT.  Bigger machines often have cast iron bases and the motor is down low in the cabinet, I was leveling a 1 ton lathe the other day (not bolted down to the foundation), all cast iron massive base and even they are not dead smooth at all speeds. It took a good 1/2 hour to get the ways true to better than 0.00025"/ft over their full span. Getting the machine accurately leveled at multiple points along the bed (getting the twist out) and stable to the foundation is the first thing to do with setting up the machine, then if needed any adjustment to the headstock,  and then once the tailstock is centered checking the turning at different points. The two ring test on this size machine is often done with something like a 1.25" bar, sometimes with rings added. If your chuck is not dead true, or the jaws skew the rod, then the test will not be valid. Anything beyond maybe 8" would most likely be supported by the tailstock, which greatly diminishes the affect of the headstock alignment and bed twist affect.

Fascinating post on the affect of inducing bed twist on a 16x40 lathe and measuring the change in the turning and the affect of the tailstock "Without the tailstock: Using the same shaft, just backing off the tailstock center, with the indicator about 2.5 feet from the spindle, I could get plus or minus 5 thou deflection on the indicator by adjusting the leveling bolt. Of note, I could quite reliably get the tailstock back to level just by bringing the indicator back to zero. Of course it helps knowing where it started from...... Bottom line, when using the tailstock, leveling makes very little difference. The tailstock centering however makes a huge difference. Without the tailstock, I could get about 2 thou per foot taper (4 thou on diameter). The numbers will be different of course for every machine." :
http://www.chaski.org/homemachinist/viewtopic.php?f=42&t=92674

Bedtime reading:
http://www.armurerieduroi.com/pages/lathe/lathe_leveling.html#1
http://www.wswells.com/data/howto/H-3.pdf
http://www.neme-s.org/Model_Engineer_Files/Align1.pdf


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## marcusp323 (Feb 8, 2016)

I'm sure I got to overthinking, yet again. Had my 1340 mounted on Mason pads & all was fine (as far as I was concerned anyway) until I tried the palm-slap-shake-test I got to reading about in this thread. Seemed like I should get some TECOs to better support my lathe & presumably remove what shake I could perceive with the obviously scientific testing method  employed. Ordered some from McMaster-Carr & crawled around in the chip & oil debris that found it's way behind & under the machine, got all the legs replaced, re-leveled & tightened down, & lo & behold, now there's more perceived shake than ever. Very noticeable at a few speeds (obvious harmonics) with or without any chuck attached. Loaded up the cabinets with about 400 lbs of bullets on the headstock side & another couple hundred on the tail. Not a lot of difference. Decided to just try a 2x2 piece of square tubing with wooden door shims, (rather than try all the work of drilling & tapping the cabinet as RIO did, at least not yet), & it made quite a difference in the magnitude of the vibrations. 
As I said in the beginning, I have been way overthinking all this. I've had no trouble with finish or chatter issues (that weren't my fault) since I started using this lathe, so why didn't I just leave well enough alone? I'm going to figure that just for me, I'm better off back where I started. More crawling, & replacing & leveling, but hey, what else do I have to do after dinner on a rainy night anyway? I'm going to figure also that like my rifles, each of these machines is liable to have it's own likes & dislikes & little quirks here & there. For what it's capable of, & the price I paid, I'm still quite happy with it.

OK, a pic of my super custom vibe damper doo-dad


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## wrmiller (Feb 8, 2016)

I have my lathe on the Tecos that Mike (zmotorsports) recommended. Never bothered to check before, but after reading through some of this thread I went out and 'smacked' the headstock on my lathe. The light and DRO vibrated, because they are on flimsy mounts. If the headstock vibrated, I couldn't tell. I did get a sore hand out of it. 

But I can hold very tight tolerances and get good finishes, so I'm not going to worry about it. I have noticed an occasional resonance vibration at certain rpms, but given that I'm swinging a very heavy set-tru chuck I'm not surprised nor alarmed. I just use my VFD to shift the rpms up or down a little bit to get rid of the resonance.


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## sanddan (Feb 8, 2016)

The best bang for your buck if you are having shimmy and shake issues with your lathe is to stiffen up the top and bottom mounting plates on each sheet metal column. The current design uses two 1/4" thick plates that are welded on 3 edges with the 4th edge unsupported. The lathe is mounted on the unsupported edge causing the plate to flex under load. Adding plate to only one end of the column will have minimal affect as they both can flex as designed. An alternate solution would be to add plate to the top of both columns and move the leveling feet on the headstock column to the corners (requires 4 leveling feet) where the current mount plate is the stiffest. I would not remove the center stiffener sheet metal piece unless you tie the columns together either by using a one piece top plate as Rio did or a one piece bottom plate.

In my case I also did not notice the ringing until Rio's video pointed it out but did have a shimmy/shake at certain RPM's that I traced to the flex in the stand. I tried adding plates to only the bottom of the columns (from plates I had on hand from another lathe) and this did not remove the shake/shimmy. Rio saw similar results adding his plate only to the top and only saw success when he stabilized both ends of the column.

Best solution if you have the ability to fabricate and weld is to order a lathe without the stand and use that money to build a better stand. You could then use the dead space as storage. I like the look of the factory stand but it has little usable storage.


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## spumco (Feb 9, 2016)

RIO said:


> Mark, your advice and information never fails to help.
> You have to watch what you tell me though, like "I would add a Marathon E467".  Next thing you know, it's on my machine.  So, the same with pouring the stands full of concrete......stand by for pictures...
> 
> I think the main thing I am hearing from Matt is BOLT THE STAND DOWN, AND IT MAKES A HUGE DIFFERENCE.  Unfortunately, I absolutely can't drill my concrete, unless I like playing Russian roulette with likely hitting a radiant heat water line that's buried in the floor.  Otherwise, if you are having instability issues, I absolutely would do that next......in addition to pouring the stands full of concrete





Total noob to the site, but not to this problem.  If you want to drill the concrete floor without hitting a radiant tube, get an IR camera.  Should be able to find a home inspector locally - or call an industrial inspection company.  You turn up the heat and they can shoot the floor and map out your tubes.  Should be able to pinpoint the tubes to within 1/2" +/-.  So if you've got 3/8" OD tubes they can get you 1-3/8" stripes on the floor in 10-15 minutes, including a coffee break.

I know most insulation inspectors or "home efficiency" inspectors would have one of the cheap cameras and probably wouldn't charge much.  If you drop the coin to have your house shot - which is dead useful for heat loss - they'll shoot your floor while they're at it.

Heck, if you were local to me I'd bring mine over from work and do it for a cup of coffee and a BS session.

Regards,
Ralph


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