# PM1236T Installation in Basement



## Ischgl99 (Feb 9, 2021)

I recently purchased a PM1236T and brought it into my basement through a Bilco entryway door and thought I would document it here for anyone else considering such a move.

I had a 9x20 lathe for many years and wanted to upgrade it, so sold it a few years ago planning on purchasing a replacement, but life got in the way and I finally got the new lathe last December.  Following is a series of photos of how I got it from my garage and into the basement. I also built my own stand for it instead of purchasing the PM one.

Here is the customary picture of the crate as it arrived.  The driver from ABF was great and moved it into my garage on his pallet jack.





I called a fellow member of a business association I am in to see how much it would cost his moving company to move the lathe from my garage and into the basement.  I’m glad I was sitting down when I got that estimate, minimum charge $800 and it could be more.  That would be a hard no!
I moved my Burke Millrite into my basement by placing the main casting on a skid and hiring a local towing company to use their flatbed to lower it down the stairs at the Bilco entry door.  That worked well, so I decided to the the same with the lathe.  Since the lathe was already on a pallet that looked suitable with some modifications, first order of business was get it off the lower shipping pallet.  My engine hoist was not wide enough to get in far enough to lift it, so I used my car floor jack to get underneath and the cut out pallet piece by piece and put up on blocks so I could make my modifications.




Once the main pallet was up on blocks, I moved the cross risers from the bottom to the top to maintain the strength they added to the pallet and giving me runners on the bottom that could be used to when sliding it down the stairs.

The carriage bolt heads were sitting proud of the bottom runners and I was concerned that would make it more difficult to slide, so I used a spade drill sharpened on the backside to counterbore the holes by inserting the drill from the bottom and then drilling from the top.  This worked FAR better than I anticipated.  It’s nice when something works better than you imagine.











	

		
			
		

		
	
I was concerned there would be too much stress for the bottom runners when the skid tips from the end of the flatbed to the stairs, so I added some wood between the skid and the lathe in the center to give it more rigidity.  Apparently I did not take a picture of that, but imagine blocking about midway along the lathe length that closes the gap between the lathe and skid.

Next post will have pictures of bringing it into the basement.


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## macardoso (Feb 9, 2021)

I brought my 12x36 down the basement. Headstock, tailstock, and carriage all came off to reduce weight.


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## Just for fun (Feb 9, 2021)

Looking forward to your progress.


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## Ischgl99 (Feb 9, 2021)

macardoso said:


> I brought my 12x36 down the basement. Headstock, tailstock, and carriage all came off to reduce weight.


I was thinking of doing that, but I would still have a lathe bed weighing in at 300ish pounds I would need to get downstairs.  As well as the time to disassemble and reassemble.


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## Ischgl99 (Feb 9, 2021)

I hired a flatbed wrecker to bring the lathe from my garage to the basement.  Since it was January, the ground was nice and frozen, so no ruts to repair in the spring!

The first picture shows the lathe being pulled up onto the bed.  I removed the motor and the gear cover so the strap would not be pushing against anything that could get broken.  The strap is wrapped around the headstock base.






I tied a rope to the other end of the lathe in case I needed to steer it down the stairs, that came in handy.






The basement entry is concrete formed steps, to enable the lathe to slide down the stairs easily, I placed 3/4" plywood over the steps with some wood braces at the top to hold it in place.






This is the flatbed lined up with the entry and at maximum angle.  At this point I was busier than a one armed paper hanger, so don't have any more pictures until it is in the basement.  The driver was able to walk the lathe off the end of the flatbed and then once it was about 2/3 of the way off, it began to tip onto the plywood.  As it was descending the stairs, I used the rope tied to the end to keep it in the middle to get through the bottom door frame.






Once it was at the bottom of the stairs, I placed a 1" bar under the lathe at the tail stock end  and used my engine hoist to lift it onto a dolly.  I needed to add a couple layers of 2x6 to lift it up high enough to clear the hoist outriggers.  Once it was on the first dolly, it was a simple matter of pulling it into the basement and placing another dolly for the head stock end.  I again used the floor jack to place the skid on cinder blocks so that I could get the lathe off the skid.






At this point, I was able to lift the lathe, turn 90 degrees and place on dollies between the outrigger legs.
	

		
			
		

		
	






Now I am able to move it to the other end of my shop and place on the stand I built.

It took about a half hour from when the wrecker arrived to when it was in my basement.  That was $125 well spent.  I decided against asking friends or my son to help move it down there since I did not want to put them at risk of injury by trying to do this ourselves.  

My next post will be the stand I built for this.


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## Tipton1965 (Feb 9, 2021)

Looking good!  Interested in seeing the stand you built.


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## 7milesup (Feb 9, 2021)

That is awesome.  Love your thinking on using the flatbed.

Following along.


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## Ischgl99 (Feb 9, 2021)

The PM stand is a bit pricey and I wasn’t sure if that was the design I wanted, so I decided to make my own.  I liked the spanning beam designs I came across, but not being able to weld, I decided to make mine out of laminated pieces of plywood.  I did the engineering calcs and a laminated plywood beam 4” by 10” wide should have a similar rigidity to the c channel used by others I saw such as David Best’s design.  I have to admit, there was a pucker factor the first time I placed the lathe on the stand and I kept the engine hoist slightly loose for a bit to make sure nothing cracked.  

The first picture is the lathe on the stand as it sits today.  I’m short at 5’-6” so I was able to set the height exactly where I wanted it, on the second try...  I was comparing several designs and apparently when I settled on this one, I forgot to factor in the beam on top of the side supports, so the lathe was 4” too high.  On the bright side, I got some extra experience with rigging!  I took the lathe back off the stand and cut 4” off the bottom and now it is just where it needs to be.






The legs have adjustable machinery leveling pads under each leg.  I routed a groove on the leg bottom and epoxied a half inch thick threaded pad about 2”x2” for the leveling pads to screw into.









The legs are laminated plywood as well with the top cross beam sitting on the legs with a center tongue glued into a groove in the cross beam.  There is stretcher bolted to the bottom of the legs to prevent the legs from splaying out.  The right and left legs are kept from racking by the plywood shelf the chip pan is sitting on one along the back.  These are screwed into the legs.






The spanning beam is bolted through the cross beam on each side.  Before putting the lathe on the stand, I tried to see if there would be any movement and it is rock solid.






Here is a picture of the spanning beam glue up.  I glued three sections of 3-4 pieces and then glued them together.  I used boards and clamps to keep the sections as even as possible and then when it was dry ran it through my thickness planer to get the top and bottom flat.  I filled in the voids on the top side with Bondo and then painted it.  






That’s the stand.  It seems to be working well.  I originally wanted the chip pan between the lathe and the beam, but the coolant drain hole interferes and I would have had to cut the beam to get that to work.  I didn’t want to weaken it, so it sits below the beam until I can come up with an alternative idea.  I will be moving my machining equipment to a different part of my basement so that I can better isolate it from my woodworking equipment.  That will be a project for warmer weather so I can seal the floor in that section before moving everything.

I made a number of changes to the electrical system, this is a three phase unit and I am powering it by a vfd.  I will go into some detail on what I did for that as well.


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## Ischgl99 (Feb 9, 2021)

7milesup said:


> That is awesome.  Love your thinking on using the flatbed.
> 
> Following along.


Thanks, it really made the move easy, and they apparently get these kinds of calls occasionally, so there was no convincing needed to accept the job.  He also said this could have also been done with a winch truck, maybe for the next piece of equipment


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## 9t8z28 (Feb 9, 2021)

This is exactly how I got my lathe in my basement!  Nice job!


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## Flyinfool (Feb 9, 2021)

Make a plan and work the plan. Love it when a plan comes together.

That is pretty close to how mine came down to. except I had wheels on the dolly to ride down the ramp. I used my full size 4x4 truck to lower it down. with NO ONE allowed in the house or basement in case it got away. But my cable has a working load of 12,000 lbs. so escape was unlikely.

My lathe came with a forged lifting eye installed at the exact center of gravity, made it easy to lift.


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## Ischgl99 (Feb 10, 2021)

9t8z28 said:


> This is exactly how I got my lathe in my basement!  Nice job!


Thanks, it’s nice to see others coming up with creative solutions too.


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## Ischgl99 (Feb 10, 2021)

Flyinfool said:


> Make a plan and work the plan. Love it when a plan comes together.
> 
> That is pretty close to how mine came down to. except I had wheels on the dolly to ride down the ramp. I used my full size 4x4 truck to lower it down. with NO ONE allowed in the house or basement in case it got away. But my cable has a working load of 12,000 lbs. so escape was unlikely.
> 
> My lathe came with a forged lifting eye installed at the exact center of gravity, made it easy to lift.


Sometimes I over think things, but in a case like this, that is a good thing.  I was thinking of adding wheels, but was concerned about the skid dropping at the end of the flatbed when the wheels moved from the deck to overhanging the plywood over the stairs until it pivoted enough.  I figured once we got it moving on the flatbed, we wouldn’t have any problem getting it down.  I installed a pulley on the front of the skid and one on the door frame that I could use to pull it off the flatbed if necessary.  We didn’t need to use it.

I was looking at a Harrison M300 that has a tapped hole for a lifting eye, it would be nice if all lathes had that.  I decided against that lathe in part because I would have needed to rent a gantry crane to get it off the trailer unless I was able to find a tilting trailer I could slid it off of.  In the end, I am very happy with this lathe, until I need 13” swing lol.


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## Just for fun (Feb 10, 2021)

Your setup looks good,  the flat bed was a great idea!   When I finely get a lathe I'll have another problem.   I have a step gravel driveway with an incline before I can get into the shop.   I don't think it will be a problem after seeing what you just acomlished.   Again Good job!

Tim


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## Janderso (Feb 10, 2021)

Just for fun said:


> Your setup looks good,  the flat bed was a great idea!   When I finely get a lathe I'll have another problem.   I have a step gravel driveway with an incline before I can get into the shop.   I don't think it will be a problem after seeing what you just acomlished.   Again Good job!
> 
> Tim


That pic of the ramp with the lathe up top is awesome!
A scary moment and exciting too.
Congratulations!


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## Ischgl99 (Feb 10, 2021)

Just for fun said:


> Your setup looks good,  the flat bed was a great idea!   When I finely get a lathe I'll have another problem.   I have a step gravel driveway with an incline before I can get into the shop.   I don't think it will be a problem after seeing what you just acomlished.   Again Good job!
> 
> Tim


Thank you!  I posted this to help others looking to do the same thing since there was not much info I could find on similar moves.  We had an early snow storm a few days after this was delivered, so I had the luxury of time to figure some of this out while the snow melted.  I’m very happy the next storm didn’t come through for a few weeks so I didn’t have to wait for spring to get it in the basement!

Since you don’t have the lathe yet, you have time to think through how you want to do it.  I wasn’t expecting the crate to be on another pallet, of course wider than my engine hoist, so there was some head scratching to figure out what to do.  I almost rented a gantry crane when I realized I had the floor jack that would help raise the skid so I could work on it.  While researching this lathe, I came across an equipment trailer that lowers to the ground and could avoid needing a gantry crane to get a machine off the trailer.  A tilt trailer could work too.  Since you have a steep gravel driveway, it might be easier to rent a trailer like that and pick it up at the depot rather than taking the risk the truck drops it off at the curb.  If you don’t have one already, a long crow bar is very helpful when needing to lift corners or raise it up a little bit to fit jacks underneath.


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## Ischgl99 (Feb 10, 2021)

Janderso said:


> That pic of the ramp with the lathe up top is awesome!
> A scary moment and exciting too.
> Congratulations!


Thanks!  I like that picture too, a perfect example of gravity being your friend or foe!  The scariest moment was when 2/3 of the lathe was hanging out off the end of the bed before it started to rotate down!  I wish I had a picture of that!


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## Flyinfool (Feb 10, 2021)

I can certainly understand the being to busy to take pics. With that much weight you have to have full attention to the job at hand to be sure no one or no machinery is hurt in the process.

The casters on my cart have 6 inch wheels to handle bumps.
I used the same cart to lower the 3400 LB mill down the steps. I will admit to doing some disassembly on that or it would have never fit thru the back door.


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## RJSakowski (Feb 10, 2021)

I also used a ramp to get machines and other heavy hardware in and out of my basement.  I made my ramp with two 2x8 rails tied together with 2x4 cross pieces.  I used either my tractor or my neighbor's Bobcat for an anchor and a Come-Along to coax the load down the ramp.  My ramp extended past the staircase by enough that we were able to place the load on it in the horizontal position and then tilting the ramp down.  This eliminates the scary moment of tilting the load to meet the ramp.  My basement has a 20" stone wall divider which provided a convenient lower anchor point.  Once into the shop area, I was able to lift the machines onto stands with either a sky hook or an engine hoist.


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## Ischgl99 (Feb 10, 2021)

Flyinfool said:


> I can certainly understand the being to busy to take pics. With that much weight you have to have full attention to the job at hand to be sure no one or no machinery is hurt in the process.
> 
> The casters on my cart have 6 inch wheels to handle bumps.
> I used the same cart to lower the 3400 LB mill down the steps. I will admit to doing some disassembly on that or it would have never fit thru the back door.


My mill is fairly small, probably only weighs 1000 lbs, but I had to disassemble that too a bit to make sure it went through the door.  I took the head/ram off and then used eye bolts through the holes for the straps.  Made it nice and easy to get it in there.


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## Ischgl99 (Feb 10, 2021)

RJSakowski said:


> I also used a ramp to get machines and other heavy hardware in and out of my basement.  I made my ramp with two 2x8 rails tied together with 2x4 cross pieces.  I used either my tractor or my neighbor's Bobcat for an anchor and a Come-Along to coax the load down the ramp.  My ramp extended past the staircase by enough that we were able to place the load on it in the horizontal position and then tilting the ramp down.  This eliminates the scary moment of tilting the load to meet the ramp.  My basement has a 20" stone wall divider which provided a convenient lower anchor point.  Once into the shop area, I was able to lift the machines onto stands with either a sky hook or an engine hoist.


I was thinking of doing something similar by using my SUV as the anchor, but I would have needed to rent a trailer to bring it around back of the house, or built a platform with wheels, as well as get a Come-A-Long, so it wouldn’t have saved me any money over the flatbed.  I still might do it that way at some point in the future, especially with the lighter woodworking machines.


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## Tipton1965 (Feb 10, 2021)

Your stand turned out good.  I wasn't sure what to expect when you said you made it out of wood.  I was pleasantly surprised.


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## Ischgl99 (Feb 10, 2021)

Tipton1965 said:


> Your stand turned out good.  I wasn't sure what to expect when you said you made it out of wood.  I was pleasantly surprised.


Thanks, I think I surprised myself!  I'm sure there were more than a few shaking their heads when I mentioned I made it from wood.  It came out better than I expected, but I think I need to add a sheet metal plate under the lathe, the hot chips are sticking to the paint.


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## oaklandish (Feb 10, 2021)

Can I ask when you placed the order... and when you received it? I have the same lathe on order as well.


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## Ischgl99 (Feb 11, 2021)

oaklandish said:


> Can I ask when you placed the order... and when you received it? I have the same lathe on order as well.


I ordered it just after Thanksgiving and it arrived December 9th.


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## oaklandish (Feb 11, 2021)

Ah ok. I ordered at the end of Dec and they are having huge shipping delay issues due to Covid. I just got pushed back another couple of months. 

Congrats on getting your lathe down into that basement. I have been remodeling and rewiring my shop and gathering parts for the VFD enclosure and lathe stand. Since I use this shop for my business, the delay is... less than convenient.


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## Ischgl99 (Feb 11, 2021)

Yeah the stocking issues can be troublesome and I bought in November to make sure I got something before they were out of stock again.  I was originally thinking of getting a 1340GT, but they were out of stock for a while too and I didn't want it delivered in the middle of winter in case we had a lot of snow.  I decided on the 1236T since it was in stock, almost $1,000 cheaper (when you factor in the 3 jaw chuck that's included), and since this is for a hobby, didn't think I needed the hardened and ground gears.  I did like the 1340GT had a 2 HP motor, and the 1236T was listed as having a 1.5HP motor, but my lathe showed up with a 2HP motor.  If you are ordering a VFD in advance, you might want to confirm what size motor will be on yours.  It is a good thing the VFD I already had was 2HP so I didn't have to buy another.

A note on the 3 jaw chuck that is included with the 1236T.  Mine has 0.007" runout with one set of jaws, and 0.005" on the other set of jaws, and the runout is in a different location for each set of jaws.  I used an end mill shank and bearing inner ring to measure from and it didn't change when the jaws were clamping in or out, so it looks like the problem is in the jaws.  I am going to take it apart to clean and see if that helps any.  I contacted PM, but never got a response on what is acceptable for this chuck.  I have a 5" Bison plain back chuck I may put on this if the 3 jaw doesn't improve any after cleaning.


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## .LMS. (Feb 11, 2021)

Ischgl99 said:


> I was originally thinking of getting a 1340GT, but they were out of stock for a while too and I didn't want it delivered in the middle of winter in case we had a lot of snow.  I decided on the 1236T since it was in stock, almost $1,000 cheaper (when you factor in the 3 jaw chuck that's included), and since this is for a hobby, didn't think I needed the hardened and ground gears.  I did like the 1340GT had a 2 HP motor, and the 1236T was listed as having a 1.5HP motor, but my lathe showed up with a 2HP motor.  If you are ordering a VFD in advance, you might want to confirm what size motor will be on yours.  It is a good thing the VFD I already had was 2HP so I didn't have to buy another.


I made the exact same call in the late fall, and am very happy I did for two reasons - I got the lathe into the shop while the weather was still good, and I absolutely love having the VFD.   When you order the 3ph package it comes with a 2hp motor.



Ischgl99 said:


> A note on the 3 jaw chuck that is included with the 1236T.  Mine has 0.007" runout with one set of jaws, and 0.005" on the other set of jaws, and the runout is in a different location for each set of jaws.  I used an end mill shank and bearing inner ring to measure from and it didn't change when the jaws were clamping in or out, so it looks like the problem is in the jaws.  I am going to take it apart to clean and see if that helps any.  I contacted PM, but never got a response on what is acceptable for this chuck.  I have a 5" Bison plain back chuck I may put on this if the 3 jaw doesn't improve any after cleaning.



I had been stressing a bit about the mediocre quality of the 3 jaw chuck included.  But, my stress level dropped when I watched / read something that said while you have the part in the three jaw, the runout doesn't matter very much as long as you do all the oprations you need while the workpiece is mounted (i.e., not unmounting and trying to remount and have it centered).   Someone smarter might correct me on my description.   I did order the PM 4 jaw with it, and got the Shars set tru type ER40 collett chuck for when I need some more accuracy / repeatability.


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## oaklandish (Feb 11, 2021)

Ischgl99 said:


> Yeah the stocking issues can be troublesome and I bought in November to make sure I got something before they were out of stock again.  I was originally thinking of getting a 1340GT, but they were out of stock for a while too and I didn't want it delivered in the middle of winter in case we had a lot of snow.  I decided on the 1236T since it was in stock, almost $1,000 cheaper (when you factor in the 3 jaw chuck that's included), and since this is for a hobby, didn't think I needed the hardened and ground gears.  I did like the 1340GT had a 2 HP motor, and the 1236T was listed as having a 1.5HP motor, but my lathe showed up with a 2HP motor.  If you are ordering a VFD in advance, you might want to confirm what size motor will be on yours.  It is a good thing the VFD I already had was 2HP so I didn't have to buy another.


Clearly they do not order enough of these things...

I ordered the 3ph motor with mine and sized the VFD according to MJ's posts and recommendations. I asked PM about the higher end set tru 3 jaw upgrade chucks that others here have ordered but, they no longer carry them. That was disappointing as well and I am not sure why they wouldn't continue to carry them. So far, a few of the great things I have read about the PM version of this lathe are no longer applicable.


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## Ischgl99 (Feb 11, 2021)

.LMS. said:


> I made the exact same call in the late fall, and am very happy I did for two reasons - I got the lathe into the shop while the weather was still good, and I absolutely love having the VFD.   When you order the 3ph package it comes with a 2hp motor.
> 
> 
> 
> I had been stressing a bit about the mediocre quality of the 3 jaw chuck included.  But, my stress level dropped when I watched / read something that said while you have the part in the three jaw, the runout doesn't matter very much as long as you do all the oprations you need while the workpiece is mounted (i.e., not unmounting and trying to remount and have it centered).   Someone smarter might correct me on my description.   I did order the PM 4 jaw with it, and got the Shars set tru type ER40 collett chuck for when I need some more accuracy / repeatability.


I bought the 4 jaw chuck too and have been using that mostly to get better at centering work quickly.  I do understand a three jaw is for parts that can be turned in one operation, or don't need the concentricity of a 4 jaw chuck, so it's probably fine.  I wasn't expecting perfect, but 0.007" seems on the high side, I would have been perfectly happy with 0.003" or less.  One thing I did notice is the jaws have different serial numbers on them, I wasn't able to find a serial number on chuck itself to see if either of the jaw sets match.  The jaws on my Bison chuck match the chuck body serial number, so curious if that should be the case with the Taiwanese/Chinese chucks, and if so is that the source of the runout.

I have been thinking about getting a collet chuck as well, or building one.  I plan on doing enough small work that it's probably worth getting.  I'll have to check the Shars one, I haven't looked on their site for collet chucks yet.

I'm glad the 2HP motor comes with the 3 phase machines, it's always nice to have more power available when turning down the speeds.  I haven't added a variable speed pot to mine yet, still playing around with different configurations to see what I like best.


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## Ischgl99 (Feb 11, 2021)

oaklandish said:


> Clearly they do not order enough of these things...
> 
> I ordered the 3ph motor with mine and sized the VFD according to MJ's posts and recommendations. I asked PM about the higher end set tru 3 jaw upgrade chucks that others here have ordered but, they no longer carry them. That was disappointing as well and I am not sure why they wouldn't continue to carry them. So far, a few of the great things I have read about the PM version of this lathe are no longer applicable.


Yeah, they seem to have a lot of things out of stock even before Covid hit.  I'm glad I bought mine before the price increase, there will probably be more soon since ocean freight prices are skyrocketing with the shortage of shipping containers.

I don't have any pressing projects, just screwing around right now getting used to the lathe and what it is capable of, so I will take my time and decide if I keep the existing 3 jaw chuck, upgrade to a better one, go with 6 jaw...  So many options LOL.  I don't want to wait too long though, there are signs of big inflation coming and I would like to be set with what I need by the end of the year.


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## .LMS. (Feb 11, 2021)

Ischgl99 said:


> One thing I did notice is the jaws have different serial numbers on them, I wasn't able to find a serial number on chuck itself to see if either of the jaw sets match.  The jaws on my Bison chuck match the chuck body serial number, so curious if that should be the case with the Taiwanese/Chinese chucks, and if so is that the source of the runout.



Feels like that merits a call to PM.   From everything I have read, those serial numbers should match.   Mine do.


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## Ischgl99 (Feb 11, 2021)

.LMS. said:


> Feels like that merits a call to PM.   From everything I have read, those serial numbers should match.   Mine do.


I plan on it, I’ve been putting it through it’s paces to see if I have any other questions before calling them.


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## Ischgl99 (Feb 11, 2021)

One thing I forgot to mention about bringing the lathe down the stairs.  Because the lathe is at a steep angle while on the stairs, oil leaked out of the headstock.  It was a good thing I left the plastic on the skid, all the oil was contained by it and easy to clean up.  If you plan on doing it this way, you might want to drain the headstock oil first.


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## brino (Feb 12, 2021)

.LMS. said:


> I had been stressing a bit about the mediocre quality of the 3 jaw chuck included. But, my stress level dropped when I watched / read something that said while you have the part in the three jaw, the runout doesn't matter very much as long as you do all the oprations you need while the workpiece is mounted (i.e., not unmounting and trying to remount and have it centered). Someone smarter might correct me on my description



Absolutely correct!
You create the new centre of the the work piece during the first operation.
If the 3-jaw is off by 10 thou. or 50 thou. who cares? It doesn't matter!

It is only when you need to flip the work end-to-end or re-chuck that you have to start considering consequences.

-brino


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## Ischgl99 (Feb 12, 2021)

I have the 3 phase option for this lathe and decided to make some changes to the controls when hooking up to the VFD.  The first thing I did was mount a junction box to the side of my stand so that I had access to it without having to move my lathe or leave a lot of room behind it.  

I have a lot of experience with VFDs and industrial controls, so decided to try some options to see how I would like to use my lathe.  I had a Teco CV7300 VFD already on hand, so used that.  It has PLC capabilities, but I need a special programming cable, so I am not using that yet, but might in the future.  That would enable me to add more features without having a lot of relays in a junction box, and I could change how it works without any new hardware.

I have a 24v power supply in the VFD panel that supplies control voltage for the machine forward/reverse and power outage circuit.  This circuit controls relays for the VFD controls.   I have a power outage protection relay controlling power to the forward and reverse relays that provide signals to the VFD.  This relay cuts off the 24DC controls power from the VFD until the relay is energized.  When moving the lever to forward for example, the forward relay is energized giving the forward signal to the VFD.  I have the pilot light on the lathe wired so that it only goes on when the protection relay is energized.  This way I know at a glance if the machine is ready for operation.  

I mostly make things in metric so I wanted to find options for threading while keeping the half nuts closed.  I like the idea of the proximity switch to thread fast and have it shut the motor off at a predictable position, but I got to thinking about speeding up returning to the thread start since I will not be able to open the half nuts to return to the starting position.  So, I installed a switch that sets the VFD speed to 50% for threading as well as setting a fast deceleration time of 1 second, and a bypass button to return the VFD to full speed when I want to reverse to the thread starting position.  I can set the gears to any speed I want knowing threading will be half that speed when the switch is enabled, and at the rated speed when reversing.  It speeds up threading a bit, but does take some getting used to.

I did not install a jog button and so far I don’t miss it.  I have the VFD programmed for a 5 sec ramp up and use the fwd/rev lever to bump the position if I need to.  I haven’t done much with that yet, so may need to change that at some point.

I plan on adding a proximity stop at some point.  I already have the sensor from a previous project, just need to make a bracket for it.  I think that might work well with my rapid reverse, use the push button to bypass the prox switch and fast reverse at the same time.  I am also going to add a DRO at some point and have been thinking about what I would need to have a constant SFM feature.  I haven’t added a potentiometer to vary the speed of the VFD yet, if I add the constant SFM feature, I will probably add the pot into that, but I haven’t really needed that yet.  If I need speeds in between that gear speeds, I may be able to set my threading switch to half speed and select a speed that may be more appropriate.  I haven’t done that yet, so don’t know if the reduced power is going to cause problems.

Anyways, that is where I am at with the controls and expect this to evolve over the next several months.  I may not stay with how I am doing things now, but I am enjoying experimenting with different options and see what works best for me.


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## Ischgl99 (Feb 12, 2021)

brino said:


> Absolutely correct!
> You create the new centre of the the work piece during the first operation.
> If the 3-jaw is off by 10 thou. or 50 thou. who cares? It doesn't matter!
> 
> ...


In theory yes, but the more eccentric the work is held, the higher the vibration will be on larger pieces.  If the chuck has runout less than the tolerances for your part, you can also rechuck it without having to go to a 4 jaw.  The other issue is when you buy something new, you expect it to be within specifications.  The standards I have found for Chinese chucks is 0.003” runout, I expect to get that or better.


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## .LMS. (Feb 12, 2021)

Ischgl99 said:


> I am enjoying experimenting with different options and see what works best for me.


That right there, is what it's all about for me.


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## 9t8z28 (Feb 18, 2021)

Ischgl99 said:


> I have the 3 phase option for this lathe and decided to make some changes to the controls when hooking up to the VFD.  The first thing I did was mount a junction box to the side of my stand so that I had access to it without having to move my lathe or leave a lot of room behind it.
> 
> I have a lot of experience with VFDs and industrial controls, so decided to try some options to see how I would like to use my lathe.  I had a Teco CV7300 VFD already on hand, so used that.  It has PLC capabilities, but I need a special programming cable, so I am not using that yet, but might in the future.  That would enable me to add more features without having a lot of relays in a junction box, and I could change how it works without any new hardware.
> 
> ...


In regard to a constant SFM, how is this possible without creating a separate drive for cross-slide since its connected directly to the leadscrew?


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## Ischgl99 (Feb 18, 2021)

9t8z28 said:


> In regard to a constant SFM, how is this possible without creating a separate drive for cross-slide?


You vary the spindle speed so the cutter sees the same speed relative to work piece.  Say you have 4” piece of 4140 and you want face it, the spindle speed at the outer diameter needs to be slower than towards the center to keep the SFM constant and at the ideal value.  I don’t know if it is practical to do, it sounds like a fun project to try.


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## Ischgl99 (Feb 26, 2021)

I’ve had some more time to play with the lathe and found a shortcoming I didn’t expect.  I mostly do things in metric and am currently working on making some machinist jacks.  I used M12x1.75 for the body thread since I have that tap size.  When I went to turn the threads on the jack screw, surprise, no 1.75mm thread setting!  After a bit of head scratching, I remembered there is a thread chart in Excel on the PM website for this and the 1340GT lathes.  I downloaded that and made some tables showing the different combinations of change gears and the threads they will produce.  I found I can use an undocumented combination of 32/40 with the transposing gears to give me 1.75mm, it also gives 3.5mm and 0.8mm that are also missing.

Attached is the tables I made for the different combinations, the cells in yellow are the thread pitches that were not exact, but should be close enough.  Some of the thread pitches are duplicated with the different gear combinations, I left them in there so that I might not have to change the gears as often if I am doing a variety of thread sizes.


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