PM 728VT one-shot oiler leak

It has been somewhat of a love hate relationship so far. I have had a few issues with it, but the more I looked into it, the more I saw people repeatedly telling folks to reach out to PM with any issues, and boy they weren't kidding. The PM tech support gnomes really know their stuff.

I plan on creating my own thread about it, now that I have most of the things resolved. I was convinced that I was going to need to replace parts, but the tech (I think his name is Charlie) suggested some things for me to try, which I did, and that has been working out very well.

My mill had a few screws loose when I got it, and I really should have gone over every inch of it before I put up up high on its new table. My Z axis on the column had a ton of slop in it. I believed it to be a bad z axis leadscrew nut but shared some closeup videos with PM and they pointed out what was probably the real issue all along. Now that I have it all snugged up my z axis seems to be great.

The included quill DRO is terrible. shamefully so. it turns itself off after a few minutes, even when it is in use, which is frustrating when you were counting on it to keep track of your z, and it doesn't kick itself back on automatically either. - Mine is actually glitching out, and PM said it was defective and are sending me a replacement. But you should just plan for replacing it with something better.

I have a few other issues, but I'll save them for my own thread.
Thanks for the info. It will most likely be several years before I will be upgrading, and things will probably change by then but still good feedback.

PM is about a 4 hour drive, so plan on making a pre-arranged visit to discuss my needs and customization (I would want optical scales and hoping I can provide them for PM to install – would use TouchDRO).


Thanks again,

Charlie
 
Since they seem to know that there are issues, maybe it’s “spring-not-loaded?”

Other than the leak, how do you like your 728VT? It’s about the largest mill I have room for as a future replacement for my Mini-Mill. Thanks!
Re: 728VT, this was my first mill so I can't make comparisons to others.

Had mine for about 2 years. I'm quite pleased with the build quality, right out of the box. The 'made in Taiwan' label sold me over other models.

Other than this new leak, and the quill DRO, no complaints on quality. I replaced the DRO with a different model and improved the mount. An easy and inexpensive fix -- but it shouldn't have been necessary.

Concur with jonnyphenomenon: support from PM has been stellar. They responded to my oil leak comment in less than 24 hours. I have a PM 1130V lathe and had some warranty issues -- due primarily to its Chinese origins. PM responded very quickly there also.
 
Mine used to drain the whole reservoir in 2 days. I replumbed the whole machine with push to connect fittings and 4mm clear tube. I added check valves to each of the output lines to stop the siphon effect. My mill does not leak at all now. https://www.amazon.com/gp/aw/d/B091T7MQXY/ref=yo_ii_img?ie=UTF8&psc=1&th=1

I am considering just installing check valves in the existing plumbing, if I can find some that can fit -- with reasonable (low) opening pressure.

Do you know what thread type is in the valve body? It looks like 1/4 NPT, but maybe BSPP? (hope not).

thx

K
 
Mine are 1/8 NPT into the valve body and M6 going into the casting for Z axis. All of my original rubber hoses cracked and leaked also, maybe because of cnc use.
 
Mine are 1/8 NPT into the valve body and M6 going into the casting for Z axis. All of my original rubber hoses cracked and leaked also, maybe because of cnc use.

You are correct. 1/8 NPT. For what it's worth, this is what the check/fitting looks like. Check valve pressed into a fitting. Of course, when I got it out it seemed to work ok.

IMG_4756.jpg
 
You are correct. 1/8 NPT. For what it's worth, this is what the check/fitting looks like. Check valve pressed into a fitting. Of course, when I got it out it seemed to work ok.

View attachment 491958
If your luck is anything like mine, I'll bet you buggered up one of the threads to get it out (but hopefully not).

Flush it out, re-install and see what happens: maybe some crud was making it stick.
 
If your luck is anything like mine, I'll bet you buggered up one of the threads to get it out (but hopefully not).

Flush it out, re-install and see what happens: maybe some crud was making it stick.
:angel: No buggers.

I will fail again. I think if I raise the hose connection point above the reservoir it won't matter if the check fails?

A couple 1/8 fittings and a 4" pipe nipple should do it.

K
 
:angel: No buggers.

I will fail again. I think if I raise the hose connection point above the reservoir it won't matter if the check fails?

A couple 1/8 fittings and a 4" pipe nipple should do it.

K

That will combat gravity/head from the reservoir, but not any pressure from the hand pump.
 
I think if I raise the hose connection point above the reservoir it won't matter if the check fails?
False. I tried this and it will still siphon :sharkattack:
 
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