My new PM932M-PDF, the good, bad and ugly

[RebelJD]

As a follow up to my previous post I wanted to provide an update on my experience with my new mill. I'm a little late getting to this, but I wanted to get some run time on the machine so I could do a thorough evaluation. And life sometimes gets in the way of these hobbies of mine. First off I want to say that I was fully aware I was buying an import machine from China and would likely need to "tune it up a little". I've been reading that the quality of China imports has been going down the past few years, supposedly due to the labor shortage associated with Covid-19. I think my machine is a testament to that. My machine had some major issues that thankfully Matt at Precision Matthews quickly helped to resolve. It is a shame that he has to do that due to the poor quality of his vendors. So what follows is what I'm calling the good, the bad, and the ugly. I've already provided most of this feedback to Precision Matthews so this is no way and attempt to throw them under the bus. Rather I hope others can benefit from this either before they buy or after.
The GOOD -
The machine and base came well packaged. The Lead Screws are nice and beefy and have about .005" of backlash, which I think is fine for this type of machine. The table movements are smooth once you get the gibs adjusted they way you want. I love the big crank handles. The power Z-axis is nice and quiet. If you are debating as to purchase this option, just do it. It's amazing how much you run it up and down. I also purchased the Power Down Feed (PDF) because I plan to do a lot of deep hole boring. So far it works very well. Lastly the DRO is terrific, I would never consider a mill without one. I have not yet used some of the advanced features but the basic functions work great.

The BAD and Ugly
By far the worse thing about the mill was the poorly ground table. It was so bad when you ran a straight edge from front to rear it would stop on the middle t-slot. There was a .005 difference in the height of the surfaces adjacent to the middle t-slot. And there was a huge gouge on the rear section of the table. You could actually see and feel chatter marks on the table. Precision Matthews offered to have the table re-ground or I could return the machine. I waited 6 months for this machine and did not want to go thru that again so I elected to have the table re-ground locally. The shop that did the work told me that had to take about .010 to get it cleaned up. They did say the table has a slight twist to it as they had to shim opposite corners .003 and .004 to get it to sit on the surface grinder without rocking. I don't know if this is going to be an issue but right now is has not been a problem.

It took about a week to get the table back and it looks great, except for that wart on the rear edge. I'm just going to live with that.

One other table issue was that the DRO scale for the X-Axis covered the ball oiler for the rear way making it difficult to properly oil that way. While I had the table off I drilled and installed two ball oilers on the top of table. I install two because I did not want a single oiler in the center of the table to be covered by the vise. If you do this mod be sure to counter sink the oiler so it does not protrude above the surface of the table.

I'm unsure how large I can make this post so I'll continue on another.

 

[RebelJD]

Continuing on with my evaluation.

Power Down Feed. I went to add some oil to the oiler on the top of the PDF housing and found it was completely full of sand. That worried me so I removed the entire PDF for inspection. There was little dirt & sand, but also absolutely no lubrication. Its fairly easy to remove the PDF, but you have to be careful to get everything in sync when you reinstall it. Play around with a little when you have it off and get comfortable with how it works. I lubricated everything and it seems to work fine. I will say though, it’s a very clever design.

Paint and Finish is terrible. Paint covered the ball oilers and there is a lot of overspray. The paint chips easily but I think it has more to do with the filler used than the actual paint. The filler used appears to be drywall compound not a true catalyzed body filler. There is 1/8" or more of filler in many areas of the machine. When removing any cover, a lot filler comes off with it. You can actually chip the paint with your finger nail. I’ve seen a lot of grumbling about this on line. This is not just a cosmetic thing. For example, the PDF on/off knob and PDF speed adjust knob uses a ball/spring to set in detents in the case. When I turned the knobs, the paint was crumbling under the knob causing it to stick. I had to remove the paint from the surface under the knob and add some grease for it to operate smoothly. There was also dirty, greasy finger prints everywhere as though whoever tested it had very greasy hands.

Electrical. Everything worked electrically, but the documentation was inaccurate. The electrical drawing in the manual I downloaded from your website is wrong. It does not show the KM1 seal in contact around the start push button. Also, the Z axis motor and X axis motor are not powered downstream of the KM1 power disconnect. The drawing in the manual that came with the machine is more accurate. Additionally, the components in the control box are labeled wrong. The picture in the manual is correct. There were also some wires labeled wrong in the small electrical box on the rear of the column. These things are likely not a big deal to anyone unless they were troubleshooting an electrical problem in the future. This is the kind of thing I did for living so I always like to check actual wiring before I energize something the first time, that’s why I found it. Also, the only ground to the base/column was the ground connection going to the spindle motor, which means the connection to the base/column was through the Z-Axis gibs. Probably not a big deal but I did run a separate ground wire to the column. There is a place on the lower column labeled as a ground.

I'll continue on another post.

 

[RebelJD]

Continuing

DRO Mount. I love the DRO, but the way it was mounted was pretty bad. The bracket that was mounted to the back of the column appears to have been installed before the filler was set as there is a deep divot in the column. The worse thing though was the bolt provided was 8mm but the holes in the bracket and the arm were about 10mm. I don’t know if I’m missing a bushing or what. It was way too sloppy to use. And with the bracket mounted on the rear of the column you could not position it very well. I ended up using a DRO mount I had from old Sony DRO and mounted it on the side of the column, its very solid and better positioned.

R8 adapters – the two R8 adapters that came shipped in the small plastic tool box were simply wrapped in paper. The ground end that fits in the Jacobs chuck has several dings in it. I ordered a keyless chuck so I likely won’t being using it but it should have been better packaged. And that cheap plastic tool box leaves a cheap impression, a simple cardboard box would be better.

Gib lock screws – The ends of the Gib Lock screws are uneven and inconsistent. Because the gibs are at an angle the ends of these locking screws need to be square or you could actually loosen a gib lock that you thought you were tightening. I had to square these up on my lathe to get a consistent feel against the gibs.

Z-axis bellow – The mounting of the bellows was horrible. It was spaced about ½” from the ways and was uneven. I was hard for me to imagine milling something to precision while looking the way this was mounted. I had to make a new mount for the upper and modified the lower mount to work.

The lower cover on the headstock was installed backwards and in doing so they stripped out a threaded hole in the casting. I installed it properly, but could only install 3 of the four screws.

Well those are the issues I've found and fixed so far. At some point I'll probably take the gearbox apart to inspect it although it seems to work fine and its very quiet. I'll continue on another post with my experiences in tramming the mill and using it on some fairly complex parts.

 

[Winegrower]

A great report. I have to say, the PM users on this site give a lot of slack to the company. And I am always amused when I read something like the comment "I don't want to buy a used tool because it may have problems".

 

[Aukai]

Thanks for posting, once you fiddle with it to get it right, I hope you will enjoy it

 

[C-Bag]

I know all about being between a rock and a hard spot. I would have been beside myself with that .004” twist. It‘s all relative I guess.

 

[Tipton1965]

I know you waited awhile to get the machine but I personally would have sent it back to PM. But then I'm pretty patient with stuff like that. Did PM offer to ship you a different model machine?

 

[RebelJD]

I know all about being between a rock and a hard spot. I would have been beside myself with that .004” twist. It‘s all relative I guess.

I have not seen any issues with the twist. I checked as best I could on my 24" surface plate and did not measure more than .001 It may have been out just on the ends.

 

[RebelJD]

I know you waited awhile to get the machine but I personally would have sent it back to PM. But then I'm pretty patient with stuff like that. Did PM offer to ship you a different model machine?

PM offered to have me return it but we never really got into a discussion on the exchange.

 

[yota]

that is pretty crappy. I have the same model and did a post on it. we have the same cosmetic issues but my table is flat as far as I can tell. the sand in your machine is pretty bad though and I guess I need to dig deeper to see if I have any. as hard as it would have been, I would have returned that machine.