# PM-1440GT, Taking the plunge, final answer?



## oregontripper (Jan 15, 2021)

At least some questions prior to making the BIG for me order.

I have decided to skip the 1440GS, gearbox and COO mainly.


1. Plan to order the 3-phase unit. With this forum's approved VFD, is it super easy to, at least initially, just hook up to run?  (Just to supply the third leg?)

2. How's the tool post PM sells for it? I'm a newb, however, I prefer to avoid buying with the intent of upgrading later. (Hence getting this awesome machine.) I have one reference that says it's plenty fine....

3. PEP package for sure. Pretty certain I want the $400 4-jaw chuck offered, correct? Good stuff?

4. How about the ulra precision keyless drill chuck, good stuff, right? (The one for $130.)

5. OMG, DRO! Cheapest one, will it matter? Self install? Or? I  have a new to me mill and I can surely d&t. Precision? Hmmm. 

6. The micrometer stop doodad. Is that purely mechanical and trips the clutch? Sorry, been meaning to figure that out. One of the awesome mods I hope to make is adding the electronic stop for use when threading. Do I need this $100 stop?

7. My lathe book is coming, I'll need a live center too?


8. I have nit-picked every detail and my only gripe is that the cross slide scale blocks the cs lock. For $10k I'd figure that'd be engineered out after several years. Pretty minor. Surely there's more? LOL Gosh, is it really that good?  

A couple notes. I think the height will be perfect. Gunsmithing and related tool making is my intent.

Take the plunge?

Thanks to all who have contributed so much here. It's great, really great.


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## Janderso (Jan 15, 2021)

The PM guys will be here shortly.
Welcome


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## xr650rRider (Jan 15, 2021)

oregontripper said:


> At least some questions prior to making the BIG for me order.
> 
> I have decided to skip the 1440GS, gearbox and COO mainly.
> 
> ...


Not exactly easy as you remove wiring from stock contactors and wire motor directly to VFD.  You then need inputs from switches and interlocks wired to VFD to control, forward, reverse, stop, etc.  I completed all wiring before ever powering up the first time.


oregontripper said:


> 2. How's the tool post PM sells for it? I'm a newb, however, I prefer to avoid buying with the intent of upgrading later. (Hence getting this awesome machine.) I have one reference that says it's plenty fine....


 I have the PM1340-GT and never used the toolpost it came with, I upgraded to the Aloris with several toolholders, later learned Shars toolholders from Ebay worked just as well for a  lot less, but the Aloris QCTP is nice and glad I bought it.


oregontripper said:


> 3. PEP package for sure. Pretty certain I want the $400 4-jaw chuck offered, correct? Good stuff?


 I upgraded to the 8" 4-jaw with the PM-1340GT and it's done everything I've needed.  It's still awfully tight after a year.  Not sure it was perfectly balanced as I get some vibration at different speeds but can usually slow down or speed up and get past harmonic.


oregontripper said:


> 4. How about the ulra precision keyless drill chuck, good stuff, right? (The one for $130.)


 I like the ultra precision keyless chucks, I have one for my PM-30 mill and the lathe and they seem well made. No complaints.


oregontripper said:


> 5. OMG, DRO! Cheapest one, will it matter? Self install? Or? I  have a new to me mill and I can surely d&t. Precision? Hmmm.


 I asked Matt when I ordered mine and he recommended the Easson 12B over the cheaper version, so that's what I got and definitely not disappointed.  I ordered it installed as never having seen one installed before, did not want that hassle.   After you see it in person, sure I could have done it but glad I didn't.   The Easson 12B had room for 3 inputs from scales, and I was able to add a magnetic scale to tailstock and then it shows up on display vs. having a separate indicator mounted on tailstock.  Not something I knew when I ordered but nice after installed.  I'd never used a lathe before and glad I started with DRO.  I don't think you have to pay your dues and start with dials.  DRO allows you to ignore backlash in dials.


oregontripper said:


> 6. The micrometer stop doodad. Is that purely mechanical and trips the clutch? Sorry, been meaning to figure that out. One of the awesome mods I hope to make is adding the electronic stop for use when threading. Do I need this $100 stop?


 I thought I absolutely had to have the mechanical stop and got it.  Realize while threading with it, the clutch does nothing.  Instead of crashing into headstock, you can crash into stop but it won't disengage.  The clutch will kick out when power feeding.  Again I'm using PM-1340GT as reference and assume the PM-1440GT has it as well.  I was convinced that I needed the proximity stop as I would be threading barrels and didn't want drama of stopping or crashing.  I bought all the parts but then saw Joe Pie video on youtube about threading in reverse so started learning that way and now have no need for proximity stop.  You will have to run a left handed tool upside down and you need a spacer so you can put tool on center, but Joe has a video on spacer as well.  For internal threads, use a left handed tool running on back of parts.  I bought some left handed micro 100 carbide threading tools and can do internal threads down to 0.375". 
  I practiced using the stop as my zero, for threading.  Then later built an inboard spider for barrel work and on the first barrel (Stolle Panda) I needed to chamber/thread, it was too short to allow use of the stop at all.  So you learn to use the DRO for zero and thread out from there.  So I don't think I've used the stop since for a stop.  I built a thru barrel flushing system and I use the stop to help support my pan that catches oil and chips but not as a stop.  


oregontripper said:


> 7. My lathe book is coming, I'll need a live center too?


I ordered both live centers that Matthews sales and have used them several times.


oregontripper said:


> 8. I have nit-picked every detail and my only gripe is that the cross slide scale blocks the cs lock. For $10k I'd figure that'd be engineered out after several years. Pretty minor. Surely there's more? LOL Gosh, is it really that good?


MKSJ had a post, where he made a plate that mounts where the follow rest bolts on crossslide and uses a bronze screw to push against the crossslide for a friction lock.  I built one very similiar and it works very well.  You actually have good control of friction and I've never used or missed the lock where scale is mounted.  If I ever need to use follow rest, I assume I'll can make some spacers and longer bolts and leave the friction lock in place.


oregontripper said:


> A couple notes. I think the height will be perfect. Gunsmithing and related tool making is my intent.
> 
> Take the plunge?
> 
> Thanks to all who have contributed so much here. It's great, really great.


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## macardoso (Jan 15, 2021)

oregontripper said:


> 5. OMG, DRO! Cheapest one, will it matter? Self install? Or? I have a new to me mill and I can surely d&t. Precision? Hmmm.


I got one off AliExpress for <$300 with 1um scales. I like it a lot. Did the self install (quite a pain in the butt) but it is accurate and has good features. If you wish to go this route, communicate with the seller to let them know you want the higher resolution scales and what length you need. Saving money was important to me. I paid a bit extra to get a 3 axis read head as well so I could later add a tailstock or compound DRO.









						219.39US $ 9% OFF|Big Lcd Digital Readout Set Display for Lathe Mill and Linear Scale Linear Encoder Ruler 300 400 500 600 700 800 900 Fast Ship|Level Measuring Instruments|   - AliExpress
					

Smarter Shopping, Better Living!  Aliexpress.com




					www.aliexpress.com


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## Stonebriar (Jan 15, 2021)

I bought the Eason DRO on the first lathe I bought and liked it.  This time I bought the Precision Machine version of the DRO with my PM1440GT and I like it just fine also.  So  saved money and just as happy.  I installed it my self, it's not that hard to install.

Matt has a nice little write up in his user manual for the 1140GT on using their DRO.

I have PM's live centers. No problems.

For the tool post I have an Aloris tool post and Shars tool blocks.

I bought the PM 4 jaw and it is a very nice chuck for the price.


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## 7milesup (Jan 15, 2021)

I would recommend the LCD DRO display.  I have the standard green colored display and find that it is difficult to read at times.  These new LCD ones look like the schnizzle...


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## macardoso (Jan 15, 2021)

7milesup said:


> I would recommend the LCD DRO display.  I have the standard green colored display and find that it is difficult to read at times.  These new LCD ones look like the schnizzle...



Here is my LCD one. Bright and easy to read. Best of all, the display update is very fast, maybe 20-30Hz. 

The ONLY gripe I have had with it is that the 1um scales have a resolution of 0.00004" (roughly half tenth), so the display automatically shows you 5 decimal places even once it is in diameter mode. a small piece of electrical tape on top of the vinyl cover solves that issue. The 2 axis scales come XY or XZ, but since I got the 3 axis unit, it reads XY or XYZ. Not a biggie and not an issue if you only want the 2 axis unit.


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## 7milesup (Jan 15, 2021)

^^^That is exactly what I was talking about.  I might have to change out the DRO head on my mill for one of those.  looks so easy to read.


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## macardoso (Jan 15, 2021)

It was almost too big for me at first, but when my head is in the work, it makes it so easy to read.


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## kb58 (Jan 15, 2021)

To the OP, it's great to see someone all excited, but an emotional and expensive decision should be thought through very carefully. Strongly suggesting forcing yourself to hold off maybe 10 days or so and continue looking at alternatives, both new and used.


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## DavidR8 (Jan 15, 2021)

7milesup said:


> ^^^That is exactly what I was talking about.  I might have to change out the DRO head on my mill for one of those.  looks so easy to read.


I have that same DRO on my mill and I can attest to the readability and ease of programming.


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## T Bredehoft (Jan 15, 2021)

I  question the need for an "Ultra precision drill chuck" on any lathe. With a spot drill to start a hole, any drill will drill on center, for a while at least, but without boring a hole, you don't know if it's concentric or not. Even with a perfect drill chuck drills will wander. I'm happy using old (20th century) Jacobs chucks.
_
Edit: _Correct typo


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## Winegrower (Jan 15, 2021)

Maybe a keyless "Ultra precision drill chuck" won't have this problem but my just "precision drill chuck" has a tendency on a heavy cut to self-tighten, and it's a pain to undo.   Have to go dig around for that spanner.   I'm happy with a key.


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## oregontripper (Jan 16, 2021)

Hi guys. Much appreciate the input. Without order and on the fly.

I have cussed 1/2 of the hand drill keyless chucks I have used....  I like precision. Have to look into it. I'll be drilling out from an existing hole, not too hard.  I just got my mill wired up tonight and made a few holes.  I bought a fairly accurate keyed chuck for it and I think it's great. I'll be running an indicator on things, see how it spins.

VFD is going to take some careful preparation. Looks very doable, although I will be needing help making sure I am doing it right. I really want this.

Better DRO screen sure sounds like a good thing. They're offering a third DRO, a magnetic option now too. I think it'd be cool to have a third display on the same screen too. I'll have time to decide.  Order of the XYZ isn't going to mess with me, but, I feel for those that have it in their head one way. 

Regarding tool posts. I am specifically wondering about the QCTP offered at $180, not the standard one.  I'll want more holders so that will be a factor. Will decide. 

Hundred bucks for a stop?  I don't know. Reverse threading has been sugested by many for the projects at hand...

$10000 for a new machine... Thing is, I have searched high and low (here comes the part I sound like a QMT commercial), what else is not Chinese, has a 2-2.5" spindle bore and likewise most critically a short spindle to my liking as well as a gearbox that isn't dumb?  Had a machine seller measure a used machine for me today,  25" spindle, deal breaker by 10".  I am new to lathes (no kidding), however, I do know the desired criteria for the technique intended to perform.  This, I will not argue, it's been done and said by others. I am going to once again carefully consider the 1340GT.  Just like many things, just one doesn't seem to be enough!


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## Cheeseking (Jan 16, 2021)

macardoso said:


> Here is my LCD one. Bright and easy to read. Best of all, the display update is very fast, maybe 20-30Hz.
> 
> The ONLY gripe I have had with it is that the 1um scales have a resolution of 0.00004" (roughly half tenth), so the display automatically shows you 5 decimal places even once it is in diameter mode. a small piece of electrical tape on top of the vinyl cover solves that issue. The 2 axis scales come XY or XZ, but since I got the 3 axis unit, it reads XY or XYZ. Not a biggie and not an issue if you only want the 2 axis unit.
> 
> View attachment 351196



Consider mounting that display up higher it looks like its right in the line of fire.


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## Watchwatch (Jan 16, 2021)

I’m not happy with the QCTP on the 1236T. I started a thread about the issue. The dovetails have .003 taper.


Sent from my iPhone using Tapatalk


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## bill70j (Jan 16, 2021)

I bought the 3-phase 1440-GT PEP three years ago.  I would do it again.  Here is a bit more input FWIW:

I thought about the VFD, but decided to wait and see if I really needed it.  I really didn't and still don't.  How about waiting to decide?
I bought PM's wedge-style QCTP for the $180.  It works as well as any of the import models that I have on my other lathes, which is fine for me as a hobbyist.  I have purchased a number of the import BX holders for about $18 each, which all work fine.
I bought the Easson ES12-B DRO from PM and installed it myself.  It's an easy installation, and the unit works fine.  However I have since bought a similar $200 unit from Ali Express for another lathe and it works just as well.  I would save the $$, if I were to decide today.
I bought the PM mechanical carriage stop and use it a lot, especially for boring.  It works fine.  But I should have just built my own rather than spending extra for the PM unit.
The carriage lock location poses a problem if you install the DRO scale on the back of the carriage.  But mksj's design is a perfect solution.  I show it on my lathe below.
I bought the PM 4-jaw, and it works great, as does the 3-jaw.  Both are high quality Taiwanese models, IMO.  But as has been mentioned, both are still pretty tight.
I bought the "high precision" PM keyless chuck.  It works fine and is more convenient than my keyed one.  Did I really need it?  No
HTH.  I have had great experience with the 1440-GT.  Just a couple of minor problems so far:

About 6 moths ago the gear that engages the worm on the power feed shaft fell off, so all power feeding stopped.  I took the apron assembly apart and discovered that the locking ring for that gear was not installed at the factory (post#12).  Simple fix, but reflective of a QC problem.
When I tried to start the lathe for the first time - no go.  Finally I called Matt and found that the inter-lock on the gearbox door was not making contact.  Numerous other PM customers have apparently had that same problem.
The apron leaks oil - not a lot, but enough to be annoying.  One of our Forum members found a fix, which I haven't yet done.
There is a weakness in the cross slide where the compound attaches, which has been discussed here.  I haven't done anything about it yet, but Matt has agreed to help.
In summary.  I hope you make the Plunge.  IMO you won't be disappointed.

*Here is a partial view of the "mksj-style"cross slide lock, also the PM QCTP and holders*


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## Dabbler (Jan 16, 2021)

@oregontripper  I'll just answer the questions you asked without reference to the other answers, so my apologies for any duplication.

1:  3 phase - Ordering the 3 phase unit makes great sense* if* you have 3ph already in your shop.  If you don't it will become an obstacle to your quickly using and enjoying your purchase.  You 'can' jury rig' a lathe for 3ph using a VFD, but it wont work the way it was intended nor will it be easy to use.  The 'best' way to hook up a VFD to a lathe is to completely rewire the control box.  It takes time and electrical skills but is very rewarding when complete.

2:  Toolposts - this is a religious and super hot topic...  I have and use regularly 4-way, American Rocker. Aloris wedge, and offshore Piston and wedge clones. I've  used Davidson and Multifix from time to time also. Each has a different pattern of use, but each has advantages and disadvantages.  If you are experienced in a particular style, get that style.  If you are just starting out, there's a long discussion that can go with this topic that should take an entire thread.

3:  PEP package - Since you are buying it only once, get the best chucks you can afford.  That's where you will easily see quality/crap.  A 4 jaw chuck can be your economy one if you have to save money.  It is way more expensive and more noticable than a toolpost or any other lathe item....

4: drill chuck - I'm going to get flamed for this, but here goes:  Consider a name brand *keyed *chuck. You can leave the key in the chuck 100% of the time... It holds better and releases better than any keyless chuck, and doesn't suffer from the newbie problem of seating the drill all the way down before tightening it. This can reduce the hold on the drill bit, and can damage the chuck as it self-tightens. I've use both kinds for over 40 years, and the keyed isn't noticeably slower, and cheaper to get good accuracy. I love the old Jacobs superchuck if you can stand .004 runout, or their ultra precision chuck, which is around .0005 or .001, I can't remember. I also have Rohm chucks which are quite good.

5: DRO -  A DRO is a nice to have on a lathe, but so far, none of my lathes have one.  (nor have I needed it) (!!)

6. Mic Stop - Get the micrometer stop.  When you've used your lathe for 10 years, you can learn to depend on it for improving your Z accuracy; and a DRO only covers part of that territory.  Some guys never use them, but I use mine quite regularly.  You set it to get a shoulder where you need it, and use the hand feed at the very end of the cut to go to the same shoulder, repeatably.  Saves a lot of time, and is the only way to do this repeatably, short of an electronic lead screw.

7. live center - yes.

8. cs lock -  a problem on several lathes I've used.  you get used to it.


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## oregontripper (Jan 16, 2021)

bill70j said:


> I bought the 3-phase 1440-GT PEP three years ago.  I would do it again.  Here is a bit more input FWIW:
> 
> I thought about the VFD, but decided to wait and see if I really needed it.  I really didn't and still don't.  How about waiting to decide?
> I bought PM's wedge-style QCTP for the $180.  It works as well as any of the import models that I have on my other lathes, which is fine for me as a hobbyist.  I have purchased a number of the import BX holders for about $18 each, which all work fine.
> ...


Great stuff.


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## oregontripper (Jan 16, 2021)

Thanks for the additional information guys. It's very helpful to me.

3-phase is not available. Overnight I have actually begun to rethink this.

Some of those pics on the compound t-nuts are pretty uninspiring to say the least.

Cross slide lock. Matt offered to have a modification done. I'll just do it myself if needed. I like the one shown above.

DRO, hmmmm. I just about had myself convinced to go magnetic. Definitely will self-install. As a side note, watching DROpros videos is great for falling asleep. Not a slight, they're great, just the material. LOL

I'm leaning towards a keyed chuck.

Really appreciate the input!


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## matthewsx (Jan 16, 2021)

Three phase is readily obtained from a static or rotary phase converter, I have this one









						SPC-3
					

Run motors at two-thirds power with the heavy duty SPC-3 Static Phase Converter. This static phase converter offers reliable performance for any industry.




					www.northamericaphaseconverters.com
				




on the back of my lathe and it does the job fine. If I want a VFD later I'll do the mods but my machine has a long way to go before then. Definitely order the three phase machine over a single phase one since you will have to replace the motor if you want to change over later.

I can't speak directly to PM machines or accessories other than to say folks around here speak highly of them and willingness to sponsor/participate in our forum is a big plus in my book. 

If I were doing it I would get the DRO installed and worry about other stuff later unless there was a special deal to be had. A keyed drill chuck will work the same as keyless for most operations but getting the 4 jaw with the machine makes sense. If you want to start working right away just order a phase converter and you should be able to hook it up and go.

John


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## mksj (Jan 16, 2021)

If you are going with 3 phase, then I would go with an RPC or a VFD, either method is not that difficult, you will get full Hp and should have less issues with surface finish. The VFD gives you controlled acceleration, braking and variable speed on the fly. Cost wise the VFD is less expensive unless you build your own RPC. The 1440GT basic VFD install is fairly straight forward on how to adapt a new 1440GT control system to activate the WJ200 VFD controls.

DRO is a never ending discussion, my take is it decreases mistakes and makes you more efficient unless you have spent many years just using the dials. Also on many lathes the dials may end up with some odd repeating interval per revolution, which makes counting turns a PTA. There are lots of choices on DRO's, resolution wise both glass and magnetic are comparable as to accuracy. Magnetic scales are smaller, easier to install and less prone to contamination issues. Price wise they have come down significantly. You can buy DRO magnetic packages from the UK, you need to specify the lengths and also 1 micron for the cross slide. Install is fairly straight forward on the lathe and a good learning project. Also some of the less expense packages are worth looking at, just a matter of budget and preference.








						Easson ES-12C LCD digital readout package including 3 linear magnetic encoders
					

3 Axis  Easson ES-12C LCD graphic digital readout package with three magnetic encoders. The encoders offer a very compact profile size and can be cut to length to custom fit the machine being installed. The package is suitable for mills up to Bridgeport 42" sized machines or 30" between centre...




					www.machine-dro.co.uk


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## oregontripper (Jan 16, 2021)

mksj, with your help, I will VFD from start! I'll get studying once it's ordered...

Thank you for the DRO link. That looks like some good kit.

All is appreciated.


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## Larry$ (Jan 17, 2021)

No expert here, so take with the usual grain of salt. I've had my PM1440HD for a bit over 4 years. Chinese made and had some relatively minor issues. I only use the Joe Pie upside down and inside out threading method, simple, works great. I've used the micrometer carriage stop a few times but mostly just use the DRO and hand feed the last little bit. I sometimes use a magnetic back dial indicatorI have the original keyed chuck that came with the machine and a PM keyless chuck that I use all the time. If I'm using a large bit I tighten it just a bit more with the spanner. Never had a problem not doing that, just a precaution. The factory wedge style tool post has worked fine. I've got PM & Shars tool holders, work fine. Did replace the set screws in several of the Shars. PM 8" four jaw works fine. 6" PM 3 jaw scroll has less error than a higher dollar 8" I bought. Carriage lock, I made one similar to what others have done not often needed. Got the taper attachment PM installed. Have worked on it to try and improve it. OK now. PM had replaced the Chinese motor with a polish one before shipping.

The quick change gear box Leaked slowly. Took the front off, the gasket was just barely caught at one point. Bought some silicone liquid gasket at the auto store. Getting all the gears and operators back in registration was not easy. It still leaks very slowly. Like someone here said the micro safety switch on the  end of the machine was off just enough that it would work, most of the time. Took me a while to track that one down. Easy fix, just adjust the switch location. At first the controls on the QCGB were grabby but now work smoothly. The Easson DRO, installed by PM, works well.  When i got the machine I opened the main gear box and checked for sand, dirt etc. It was very clean. Tail stock was properly aligned. A steel spring pin had been used in place of the brass one that is shown on the parts diagram, I fixed that.  There are no vibration issues. I'm running on 208 V three phase. This machine has a one piece cast Iron base, Total weight is about 2700#s+-. I do a mostly repair work. The price has gone up substantially and the included accessories has gone down since I bought. All dealings I've had with PM have been good.


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## bill70j (Jan 17, 2021)

oregontripper said:


> mksj, with your help, I will VFD from start! I'll get studying once it's ordered...
> 
> Thank you for the DRO link. That looks like some good kit.
> 
> All is appreciated.


@oregontripper
Please keep us informed with lots of pics once you get going.  I would be especially interested in exactly how you do the VFD.  Maybe I'll finally take that plunge.
Thanks,  Bill


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## jbolt (Jan 18, 2021)

My $0.02 on Lathe Chucks. Whatever brand/quality you decide on I always recommend getting chucks with 2-piece jaws so you can use soft jaws. I regularly use soft jaws on both 3 & 4 jaw chucks. For 3-jaw chucks I prefer adjustable chucks that can be dialed in to near zero runout. 

On drill chucks you will eventually have a multiple of sizes and quality. I use my precision keyless for fine work and crap imports for pre-drilling holes for boring or reaming. Keyed chucks hold tighter than keyless. For large holes I use 3MT tang drills I buy as needed.

Om my 1440-GT I went from single phase to three phase. The lathe ran great with the single phase motor and would serve most well. I wanted the extra options available with a VFD plus I believe the soft start with a VFD is easier on the gears.  

Upgrading from a 1ph or factory 3ph the difference is cost of the motor, motor sheave and making a motor mount. The only 3hp 3ph motor I could find that would fit is the Marathon E470. It is a beast of a motor and I would venture to say more powerful than the factory 3hp 3ph which is the same frame size as the 2hp single phase motor. 

There are a couple of members on this forum that changed the factory 3ph to the Marathon 3ph due to issues with the factory 3ph/VFD combo. I would recommend looking those up.


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## oregontripper (Jan 18, 2021)

Moving this direction after a slight detour....


The PM lathe chucks aren't going to be beat for anything near the money. I'll get the PEP package 3-jaw and the independent 4-Jaw.


Three phase, albeit with it's VFD install challenges will be real nice. Speed dial on the fly?, soft start for sure. Still a couple days to change my mind.


PM wedge QCTP for the win.


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## 7milesup (Jan 18, 2021)

oregontripper said:


> Moving this direction after a slight detour....
> 
> 
> The PM lathe chucks aren't going to be beat for anything near the money. I'll get the PEP package 3-jaw and the independent 4-Jaw.
> ...


Wait. 
Didn't you get that other one from eBay?


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## oregontripper (Jan 18, 2021)

7milesup said:


> Wait.
> Didn't you get that other one from eBay?


So, I can only get one at a time apparently... 


I'm keeping the gorey details quiet, but, it's going to cost me! LOL 

PM1440GT - final answer!


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## Just for fun (Jan 19, 2021)

Sorry you didn't get the other one.   But the 1440GT looks like one heck of a nice machine!


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## oregontripper (Jan 21, 2021)

Hello again.

A question or a few about chucks. 


Considerations between 8" and 10" of the same construction, quality etc...

Is a larger heavier chuck harder on the lathe? Conversely, does that heavier weight and more momentum lead to better finishes, or cuts? 

Thinking d1-5 direct mount  independent 4-jaw holding a "jig"  about 3.5" diameter.  Pros or cons 10" vs 8" 

Of course money is no object! LOL 


Would I ever regret splurging for a forged steel chuck? 

Input is appreciated.


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## xr650rRider (Jan 21, 2021)

If your talking about an action truing jig, then a 8" 4 jaw holds it just fine.  I actually mounted my action truing fixture on a D1-4 backplate, so when installed it runs true, without having to dial it in like in a 4 jaw.  The larger the chuck is, the more it weighs and the more it weighs, the less likely you'll be able to easily swap it out without some mechanical assistance.  The larger diameter also has more rotational energy, so slower to stop.  I've been satisfied with the 6" 3 jaw chuck that came with PM-1340GT preferred equipment package and the precision 8" 4 jaw I added at purchase.  I don't think anyone is ever going to say they regretted buying a higher quality/higher precision chuck but your probably going to have to be well above $1000 each, to beat the ones that could come with the purchase for about $400 (if they were in stock).


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## Rifleman1384 (Jan 21, 2021)

Just my .02, I have the same machine on order since the end of Oct beginning of Nov. I have heard good things about the 8" 4 jaw chuck that PM sells. One thing to consider is if you are going with the 1440GT because of the spindle bore, the 8" 4 jaw they sell thru hole is smaller that the spindle bore. Just something to consider and make sure you are aware of. I decided to go another way. I also tried twice to pay and upgrade to a better 3 jaw and was told both times not possible even though some have been told no problem. In my most recent attempt I was told that the Chandox chuck will be months out. I'll start with the 3 jaw that will come with the machine and if I out grow it or get to the point I fell I need something better well it's just money right??


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## jbolt (Jan 21, 2021)

I have yet to find a need for a 10" chuck on my 1440GT. The 8" are heavy enough to lug around. 

Check the manufacturers max RPM rating. I believe most 10" chucks are less than the max RPM of the 1440GT.

My 8" 3 & 4 jaw chucks are both Gator brand. I have been very pleased with both.


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## xr650rRider (Jan 21, 2021)

I just measured my 8" 4 jaw and bore ID is 1.958" and I bet there is enough meat there to take .042" off with a boring bar to make it 2" ID if you just had to have 2".


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## oregontripper (Jan 21, 2021)

Thanks guys. 

Some good ideas to consider.

Yes, the PM 4-jaw was on my list. 



Since we're spending theoretical money.... 

I am wanting a Dorian 14 piece starter set for the tool post. 


Anyone running a 3hp three-phase off a rotary phase converter? Will a 5hp idler get it done?


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## davidpbest (Jan 21, 2021)

I do not recommend a starter set.  I've been down this path.  Dorian packages into those sets a bunch of tools that are not very useful.  Buy the QCTP and the tooling separately.


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## bill70j (Jan 21, 2021)

oregontripper said:


> Anyone running a 3hp three-phase off a rotary phase converter? Will a 5hp idler get it done?



I had a 5 HP RPC for my 2 HP 3-phase mill.  Then I got the PM-1440GT, hoping the RPC would handle it.

No Go.  I couldn't get the 2000 RPM lathe speed without tripping its breaker.  So worked out a deal with North American Rotary to upgrade with a second 5 HP idler.


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## Aukai (Jan 21, 2021)

I have a PM 8" 4 jaw, not the ultra precision, and I found an older steel Pratt on Ebay. The Pratt(England) is a smoother chuck to dial in, the brand new PM went back in the box.


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## 7milesup (Jan 21, 2021)

bill70j said:


> I had a 5 HP RPC for my 2 HP 3-phase mill.  Then I got the PM-1440GT, hoping the RPC would handle it.
> 
> No Go.  I couldn't get the 2000 RPM lathe speed without tripping its breaker.  So worked out a deal with North American Rotary to upgrade with a second 5 HP idler.
> 
> View attachment 351957


Bill....
How loud is that RPC when it is sitting on the floor like that?


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## 7milesup (Jan 21, 2021)

Aukai said:


> I have a PM 8" 4 jaw, not the ultra precision, and I found an older steel Pratt on Ebay. The Pratt(England) is a smoother chuck to dial in, the brand new PM went back in the box.


I have a small Pratt on my 1022 lathe.  It is not a true set chuck, but it is head and shoulders above what came with my lathe.


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## bill70j (Jan 21, 2021)

7milesup said:


> Bill....
> How loud is that RPC when it is sitting on the floor like that?


It's loud.  The frame holding the motors is sitting on soft rubber feet, but the motors groan a lot.  Fortunately only two  of my machines are 3-phase.

Bill


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## oregontripper (Jan 21, 2021)

xr650rRider said:


> If your talking about an action truing jig, then a 8" 4 jaw holds it just fine.  I actually mounted my action truing fixture on a D1-4 backplate, so when installed it runs true, without having to dial it in like in a 4 jaw.  The larger the chuck is, the more it weighs and the more it weighs, the less likely you'll be able to easily swap it out without some mechanical assistance.  The larger diameter also has more rotational energy, so slower to stop.  I've been satisfied with the 6" 3 jaw chuck that came with PM-1340GT preferred equipment package and the precision 8" 4 jaw I added at purchase.  I don't think anyone is ever going to say they regretted buying a higher quality/higher precision chuck but your probably going to have to be well above $1000 each, to beat the ones that could come with the purchase for about $400 (if they were in stock).


I'd be interested in more details on your jig/backplate set up.


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## 7milesup (Jan 21, 2021)

bill70j said:


> It's loud.  The frame holding the motors is sitting on soft rubber feet, but the motors groan a lot.  Fortunately only two  of my machines are 3-phase.
> 
> Bill


Hmmm.  That is a bummer but thank you so much for the response.


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## 7milesup (Jan 21, 2021)

oregontripper said:


> I'd be interested in more details on your jig/backplate set up.


Oregontripper...did you get my PM?


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## oregontripper (Jan 21, 2021)

More thanks to all...

RPC... Had better go 7.5 or 10. 

I want the 3hp, and 3ph but not the VFD challenge initially. Plug'n'Play I would. 

Also my mill is a bit of a weirdo with a 2 speed motor and I'd like to see it at full hp as designed. Its on a SPC now. 

Plus, who doesn't want to get 3-phase panels, breakers, and wiring all rigged up! ChaaChing! LOL


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## oregontripper (Jan 21, 2021)

Want


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## oregontripper (Jan 21, 2021)

7milesup said:


> Oregontripper...did you get my PM?


Don't see one.


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## 7milesup (Jan 21, 2021)

Hmm


oregontripper said:


> Don't see one.


Hmmm.  Ok.  I wanted to talk to you directly.

Edit:  Sent


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## oregontripper (Jan 21, 2021)

7milesup said:


> Hmm
> 
> Hmmm.  Ok.  I wanted to talk to you directly.
> 
> Edit:  Sent


Got it. Sounds good!


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## xr650rRider (Jan 21, 2021)

oregontripper said:


> I'd be interested in more details on your jig/backplate set up.



4" OD, 1.65" ID, 6" OAL, aluminum tipped set screws, slot cut for a bolt handle if you want to true a bolt.  I think I bought the D1-4 backplate from Grizzly or CDCOtools.








Back of aluminum jig is tapped 3/8"x24 and bolted to D1-4 backplate.


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## oregontripper (Jan 22, 2021)

xr650rRider said:


> 4" OD, 1.65" ID, 6" OAL, aluminum tipped set screws, slot cut for a bolt handle if you want to true a bolt.  I think I bought the D1-4 backplate from Grizzly or CDCOtools.
> 
> View attachment 351991
> 
> ...


Very nicely done! Might copy that concept! 


Thanks for sharing.


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## oregontripper (Jan 22, 2021)

Found a 10hp Baldor.   Moving ahead with the RPC. 

Curious. Is a static phase converter (1-3hp) supposed to make crazy end of the world noises when it's making the third phase, like Thor's hammer hitting lightning???


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## matthewsx (Jan 22, 2021)

oregontripper said:


> Found a 10hp Baldor.   Moving ahead with the RPC.
> 
> Curious. Is a static phase converter (1-3hp) supposed to make crazy end of the world noises when it's making the third phase, like Thor's hammer hitting lightning???


Mine doesn't. It makes a pretty decent buzzing sound but no hammering.

Of course mine is a static converter, it looks like you're checking a rotary converter. Two different things....

John


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## oregontripper (Jan 22, 2021)

matthewsx said:


> Mine doesn't. It makes a pretty decent buzzing sound but no hammering.
> 
> Of course mine is a static converter, it looks like you're checking a rotary converter. Two different things....
> 
> John


I have a static converter now, just new. It's more than buzzing. 

Thanks


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## matthewsx (Jan 22, 2021)

oregontripper said:


> I have a static converter now, just new. It's more than buzzing.
> 
> Thanks


Call the manufacturer.

John


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## jbolt (Jan 22, 2021)

As I have no experience with RPCs what is the cost in electricity vs. a VFD? The RPC is always running while on correct? Where a VFD draws on demand? 

At 3hp and under it seems to me the VFD offers more advantages is cost to setup and then to operate? I suppose it may not be an issue in a hobby environment but I know my electricity bill reflects my usage when I work on projects that take lots of hours.


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## oregontripper (Jan 22, 2021)

jbolt said:


> As I have no experience with RPCs what is the cost in electricity vs. a VFD? The RPC is always running while on correct? Where a VFD draws on demand?
> 
> At 3hp and under it seems to me the VFD offers more advantages is cost to setup and then to operate? I suppose it may not be an issue in a hobby environment but I know my electricity bill reflects my usage when I work on projects that take lots of hours.


If there was a plug-n-play VFD solution it'd be a viable option.

At idle, I believe the cost to operate a RPC is negligible. Hopefully, lol.

I desire the 3HP motor, 3PH, and option to VFD down the road.


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## Dabbler (Jan 22, 2021)

My RPC is rated at 15HP, which is around 11KW max.  It takes around 300W idle, if that helps - that's around 3% losses or 97% efficiency.  These values are not trying to be exact, no need.  The 300W was measured on a 1% wattmeter. 

It would be reasonable to expect these numbers to scale, so a 5 HP idler motor might tale a little more than 3% to idle, say 120 watts.  You should use a 5HP rotary to start a 3HP motor, in ballpark terms.


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## Weldingrod1 (Jan 22, 2021)

My home built static was noisy until I got the current controlled relay right. The contacts chattered.

Sent from my SM-G892A using Tapatalk


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## oregontripper (Jan 23, 2021)

All's good. Moving ahead with plans for a10hp RPC system.   For now, just have purchased the idler motor, a used Baldor, which I should see Monday.

More than machine energy, heating will be a concern if I spend much time in the shop (I like the sounds of that better than garage).  


Continuing to read more threads here - just a great forum. Thanks guys.


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## Larry$ (Jan 23, 2021)

50 years ago I made a RPC from a used motor a set of capacitors, one momentary contact switch and one on/off switch. It worked fine for 5 years or so until I moved to a place with 3 phase. The only reason I used capacitors was to give that 3rd leg a kick to start the motor spinning. As soon as I released the momentary contact switch they were out of the circuit. I enclosed the caps because it is possible for them, to under go "unplanned disassembly!" You can avoid the caps by using a small single phase motor to start the 3 phase motor spinning, then "de-clutch" the little motor. I suspect none of this meets the national electric code.


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## Dabbler (Jan 23, 2021)

@Larry$ I get that it worked.  If you had checked with an RMS meter you would have found that you 3 phase legs weren't voltage balanced.  The trick is to get the legs to all be 220 volts.  It is harder than it looks.


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## Larry$ (Jan 23, 2021)

Dabbler said:


> @Larry$ I get that it worked.  If you had checked with an RMS meter you would have found that you 3 phase legs weren't voltage balanced.  The trick is to get the legs to all be 220 volts.  It is harder than it looks.


Yes, I know they weren't voltage balanced. I didn't care. The motors it was running almost never operated at full power. This home brew RPC will never provide full power on the motors it powers. Maybe 85%??

I would hate to have to go back to using single phase power! My current shop has 800A 208V 3 phase. 208V was a mistake in some ways but it was that or 460/480.


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## wngman (Jan 24, 2021)

Any one here experienced a knocking noise coming out of the gearbox on a persision mathews 1440gt it came then it gone


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