Looking for my perfect size hobby mill....

Mr Mike said:
Hello...
I appreciate the info on the PM-932, I hate oil leaks. With all my research I found that the PM-728 is mostly a better quality version of the Grizzly G0704 that I am currently doing a tear down & clean up on.... The G0695 you point out looks like a very capable machine with plenty of range.

If you don't mind me asking, if you worked out the bugs in your PM-932, would you say its a pretty decent capable machine for a first hobby Mill.
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Hi Mike, the oil leaks seem to be solved, there are two back-to-back seals on the quill that are above the oil level that were destroyed due to loss of oil and the machined spindle drive was rough, I smoothed and polished it. when I replaced them, I put Teflon grease between them. also the seals on the gear selectors were leaking around the shaft and at the casting. the casting is very poor, so I used silicone sealant at the casting, the shaft had sharp edges at the holes for the roll pins that I smoothed.
the motor problem was two things, the centrifugal switch moved up the motors shaft so I pinned it in place and shimmed the electrical switch assembly so contact would be made.
I also now try to limit my starts by letting the motor run when doing edge finding.
I had to replace the forward-reverse switch. It's not large enough for the current the motor needs for startup, I looked at the same machine from Grizzly and found they had a far better electrical system (30-amp contactors) for stop-start.
I am now working on a 3-phase motor and drive to adapt to the gear box, I had to make an adaptor plate for the motor that I chose.
Rich
 
Rich Berg said:
Hi Mike, the oil leaks seem to be solved, there are two back-to-back seals on the quill that are above the oil level that were destroyed due to loss of oil and the machined spindle drive was rough, I smoothed and polished it. when I replaced them, I put Teflon grease between them. also the seals on the gear selectors were leaking around the shaft and at the casting. the casting is very poor, so I used silicone sealant at the casting, the shaft had sharp edges at the holes for the roll pins that I smoothed.
the motor problem was two things, the centrifugal switch moved up the motors shaft so I pinned it in place and shimmed the electrical switch assembly so contact would be made.
I also now try to limit my starts by letting the motor run when doing edge finding.
I had to replace the forward-reverse switch. It's not large enough for the current the motor needs for startup, I looked at the same machine from Grizzly and found they had a far better electrical system (30-amp contactors) for stop-start.
I am now working on a 3-phase motor and drive to adapt to the gear box, I had to make an adaptor plate for the motor that I chose.
Rich
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That is quite a few issues, I think whatever mill I get its going to have problems and like you i'll have to work thru them too, I've read so many casting issue threads across many diff mills it'd make head spin..

It sounds like you have most the issues solved with your mill now, would you trade it for the PM-928T if neither mill had any issues... the 9" table on the PM932 adds a lot of usable real-estate. based on every thing I've read the PM-932 is a much more capable machine then the PM-928,

Thanks for you input, Mike.
 
Mr Mike said:
That is quite a few issues, I think whatever mill I get its going to have problems and like you i'll have to work thru them too, I've read so many casting issue threads across many diff mills it'd make head spin..

It sounds like you have most the issues solved with your mill now, would you trade it for the PM-928T if neither mill had any issues... the 9" table on the PM932 adds a lot of usable real-estate. based on every thing I've read the PM-932 is a much more capable machine then the PM-928,

Thanks for you input, Mike.
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Mike, no. I would be now looking for an affordable knee mill, maybe a Grizzly GO695 or a PM-935TS/TV, no more single-phase motors for me on a mill.
the people a PM were nicer to me when I had a problem. if I could send it back, I am sick of working on this thing instead of my projects.
Rich
 
Depending on finances, I'm hoping that sometime early next year I can replace my little PM(Weiss)25. I'm done with Chinese machines. I've had too many bad ones. So my choices will be between the PM-728VT or the PM-833TV of the bench mills, or if I can manage it, I'll get another PM-935TS 3-phase and put a VFD on it. The 935TV has a single phase motor on it and uses a Reeves drive for the variable speeds, so that won't be an option for me.
 
Mr Mike said:
Hello Sir.
Rich Burg said a few posts back that he's had a lot of issues with his PM-932, real bad oil leaks and such... wonder if that's an issue with other gearhead mills as well, If I remember you have the Variable speed version so you wont have that issue, Have you heard of anyone else with gearhead mills that have excessive oil leaks..?

Thanks Mike.
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B2 has an older CNC gear head, which isn't offers as CNC any longer, that he has had issues with it. I think that Machine had other issues also which is why it isn't available. I was worried about low end torque on the variable speed model, I can tell you that isn't a problem and knowing what I know now the "V" model is worth the difference. The "V" in the 940 and I believe in the 932 as well have a 2HP 3Phase AC motor driven by a VFD which provides great Torque all the way through the RPM range which cancels my desire to have Gears, and by default, gear oil in the head.
 
Rich Berg said:
Mike, no. I would be now looking for an affordable knee mill, maybe a Grizzly GO695 or a PM-935TS/TV, no more single-phase motors for me on a mill.
the people a PM were nicer to me when I had a problem. if I could send it back, I am sick of working on this thing instead of my projects.
Rich
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I very much like my PM940V-PDF, I have had a couple issues mostly self inflicted, nothing major. I originally wanted the 940M, I am glad I wound up with the 940V.
 
My ACRA has had no issues with castings , I did find the power drawbar was short, and not getting enough thread engagement. It has been a great machine.
 
wrmiller said:
Depending on finances, I'm hoping that sometime early next year I can replace my little PM(Weiss)25. I'm done with Chinese machines. I've had too many bad ones. So my choices will be between the PM-728VT or the PM-833TV of the bench mills, or if I can manage it, I'll get another PM-935TS 3-phase and put a VFD on it. The 935TV has a single phase motor on it and uses a Reeves drive for the variable speeds, so that won't be an option for me.
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Hi, I'm with you on the 3-phase thing, when I was working I had been exposed to a multitude of VFD's although they seem like the silver bullet they do have their issues. they cause currents in the armature that eat bearings. also can do harm to the motors windings so most motor manufacturers offer a "VFD" ready motor that has better insulation and armature grounding of some type.
for me the way I would use the mill the motor would probably last a while.
on my mill I am installing a low cost 1.5 hp 3-phase motor and drive, I plan to install a grounding brush of some sort to protect the bearings.
Rich
 
Rich Berg said:
Hi, I'm with you on the 3-phase thing, when I was working I had been exposed to a multitude of VFD's although they seem like the silver bullet they do have their issues. they cause currents in the armature that eat bearings. also can do harm to the motors windings so most motor manufacturers offer a "VFD" ready motor that has better insulation and armature grounding of some type.
for me the way I would use the mill the motor would probably last a while.
on my mill I am installing a low cost 1.5 hp 3-phase motor and drive, I plan to install a grounding brush of some sort to protect the bearings.
Rich
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I only had my 935 for about 5 years, but never had any issues with either it or the VFD.

I'm going to do some research on the design of VFDs. I've never heard of the bearing issue and am curious how a variable frequency 3-phase voltage would cause that. Always learning something. :)

Edit: Nevermind. Had a Senior Moment and forgot that VFDs are PWM switchers, not sinusoidal analog. I'm getting old... :(
 
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Hello All...

Thanks to everyone for their input, I know for sure the PM-728 is not the machine for me.. I had my sights on either the PM-727V or the PM-932, a good price point and capability on paper for mills to learning on, I'm not looking for my forever mill just yet.

After doing a lot research I have no desire to spend 3k+ on a mill and then have to fix issues, I was thinking ok what about the PM-932V @4k well then why not a bit more and get the PM-833TV @5k, there's just no end in sight... I apologize I'm just frustrated and have to stop.

Unfortunately here in Vegas we don't have much in the way of older stock to go see, Its truly diamonds in the rough and get lucky... So I'm kind of stuck buying new, I was really excited to get this all figured out and have a new mill delivered this summer - but with those Mills out of the picture Its just not going to happen.

For now at least I have the G0704 to mess around with and figure some things out..

Thanks Mike.
 
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