G0755 (or PM932) speed question - is this all you need?

BFHammer

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H-M Supporter Gold Member
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First I want to say thanks! I'm a longtime woodworker, a hobby welder/fabricator and am sliding rapidly down the hobby machining slope. This forum and it's members have been an invaluable source of information as i have lurked and read and read and read. I also imagine in the long run it will be a big help in parting me from my money!:D

Anyway - I am shopping for a mill. After endless reading and consumption of youtube videos I'm close to pulling the trigger on a G0755 or possible a PM932 - very similar machines from what I can tell.

My question as a newbie machinist is with these machines have you ever been lacking for an appropriate speed? On the 60hz machines the specific speeds appear to be 90,210,345,670,1180 and 1970. My experience with drill press type operations is with belt driven machine and more speed options.

Any feedback on this or other considerations is greatly appreciated!

Thanks,
Mark
 
First off Welcome! Second you have come to the right place to ask your question the guys here will be more then happy to give good opinions....... and help you spend your money. :grin big: I own a PM-727m which is a bit smaller then a 932. I had the same concerns with speeds and using the input from here am satisfied with them as is. For me manual machining is all I will ever do so the available speeds are fine. I was going to get the Grizzly equivalent of my 727 because it was a bit cheaper but took a close look at the comments on QMT and PM machines and decided that QMT customer service would be worth the little extra I would spend. Look in the PM section here and get a feel for the machines in general and the comments and outcomes of the people that have had issues and I think you will see what I mean. I am very satisfied with my PM-727m and Matts service and plan to make my next purchase from him. This is only my opinion, from a novice that can turn big pieces of metal into smaller pieces sometimes getting the part I want. I'm sure more people will chime in and help out too. Might want to fasten your seat belt and lock up the credit card because feature creep and machine size considerations will be flying soon! :cool 2:
 
The speed thing is very much dependent upon the kind of tooling you choose and the materials you use. If using HSS, cobalt or solid carbide end mills in most common materials then the speed range you cited should be adequate. Certain cutters, like inserted carbide fly cutters, do better at very high speeds but will perform adequately in the speed range of the 932. Boring heads cannot run at high speed unless they are balanced so again, the 932 speed range should be fine. Drilling, even with small drills, will be fine with the 932's range.

Bottom line - the range is adequate for most work. It would be nice to have variable speed but even without it, you should be fine.
 
Thanks for the info. I think I can certainly relate to to the "feature creep". From my reading and youtube education it does seem that there are multiple ways to accomplish most tasks.
 
I have the G0755 and wish it would do two or three times its current top speed. That said I have used end mills as small as 3/32" with great success. Just takes longer.
Dave
 
I agree with Dave. I have the G0755 and have not had a problem with the speed range but when working with some of the small tooling or with diamond tools higher speed would be nice.
 
I have a PM-932 converted to CNC. I found that running a 1/4" carbide end mill in aluminum at 1970 rpm is like watching corn grow. Recently I added a VFD and belt drive. I can now run the same 1/4" end mill at 8000 rpm with a feed rate of 72 IPM. Speed is your friend if you want to remove metal quickly. If machining time is not important then the stock speeds will do just fine.

Tom
 
I have had my G0755 for awhile now and it does everything asked of it. This is a heavy duty Mill/Drill and not a high speed router, so when used within its speed range, it performes as advertized. If it's high speed routing or cutting your looking for, then it would be best to look at something else and not subject the machine to higher RPM's it was not designed for.
 
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