PM-932M or PM-835S on the fence

I need a better keyed chuck. I initially used it but I got as much slippage as I do with my Llambrich non-keyed. I've broken far too many small taps with the Llambrich. I think I need a hands-on lesson from a pro. LOL
 
The best keyed chucks today (other than the Llambrich Hexa) are Vertex from Taiwan IMO. I’ve tried all lots of brands including current production Jacobs, Accupro, regular Llambrich, etc.
 
mksj said:
Travel (X, Y, Z) and Z axis height (table top to nose) becomes pretty important as you start to work on larger parts, in particular when you have the vice height, the part and then try to tap a part. Also the Y travel is often a limiting dimension on many bench top mills. The PM-833 and PM-840 have travel dimensions that are close to what you would have with a full size knee. QMT has a nice comparison sheet of their benchtop mills so one can compare the different models. I agree with David as too trying to squeeze such a wide operating RPM with a single speed belt drive, so more geared to higher RPM work. It should be OK for most work other than low speed (under ~200 RPM) with big drills and cutters. As far as material removal, one can use a rougher for rapid metal removal.

Per what Bill just posted, ead droop or nod, is where the head at the spindle end may lean slightly backwards due to wear and play in the gibs. The heads can be quite heavy, and over time you can get a bit uneven wear in the gibs, if you need accurate work I would lock the head and use the spindle. On benchtop mills vertical alignment of the column is not adjustable, other than shimming the column, on a J head knee mill the nod (front to back) of the head is adjustable.
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This is why I bought my PM935. Not because it was more rigid than my CO 9x40 (it isn't), but because I do operations where a tilting/nodding head is more useful than being able to drill large holes in boiler plate. /s ;)

As many here know, I work on small stuff and seldom use anything larger than a 3/8" or 1/2" end mill. I think I use 1/4" end mills the most. I do have to make holes in 4140 that are almost .7" in diameter, but I drill to between .4 and .5" and bore the remaining as I need accurate holes as well as a bunch of sizes they don't make drill bits for. I actually don't think I've ever run my mill in low range come to think of it. I have no need for it.

I also don't power tap, as I prefer to feel the tap cutting, and I do a lot of tapping of 32 and 40 tpi which if power tapping I'm just asking for a bunch of broken taps.

If the OP doesn't need to drill big honking holes, then he might be better off with a high(er) speed spindle and no gears in the head. I ripped out the gears in the head of my CO within the first week and replaced them with a two-step belt drive and higher class bearings. With the VFD I could get about 6k spindle rpm which was great when working with little 1/8" endmills.
 
We've probably beat this to death. Each machine has it's strong and weak points. And each of us have our preferred methods of work. While Bill finds the Tilt & Nod capability of his PM935 fits his work, I would trade Tilt & Nod any day for more rigidity since I tilt or angle the part so I don't have to re-tram the head all the time. And I would trade the belt drive for geared head any day - in fact I looked very closely at adapting an RF45 head in place of the J-head on my PM935. And this torque topic is not just about drilling "big honking holes" either. To each his own.
 
Thanks again for all the help everyone. I've decided I don't need a larger knee type mill, and really the 932 may be a bit of overkill for me. I've narrowed it down to the PM30MV and the PM932M now. It looks like the 30 doesn't have power downfeed and the 932 doesn't come with the powered x-axis drive (or, I'm not seeing it on the website at least...). I like the idea of having a variable speed control and x-axis drive on the 30, and not sure I'll ever need the power downfeed on the 932.

Leaning towards the 30 at the moment, it's probably all the machine I'll ever need. I'll wake up one day soon with a decision I'm sure.
 
Skowinski said:
Thanks again for all the help everyone. I've decided I don't need a larger knee type mill, and really the 932 may be a bit of overkill for me. I've narrowed it down to the PM30MV and the PM932M now. It looks like the 30 doesn't have power downfeed and the 932 doesn't come with the powered x-axis drive (or, I'm not seeing it on the website at least...). I like the idea of having a variable speed control and x-axis drive on the 30, and not sure I'll ever need the power downfeed on the 932.

Leaning towards the 30 at the moment, it's probably all the machine I'll ever need. I'll wake up one day soon with a decision I'm sure.
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I am SO glad I chose the opposite from you. I bought the 835S and swapped the motor for 3-phase and a VFD. It's a great machine with all the capacity and rigidity I need. When your "rigid" machine is out of tram and needs nodding, what do you do?
Of course I had a crappy HF machine (which is particularly bad) but I added a whole lot of stiffening and adjusting hardware to provide good tramming capabilities.
 
i just got a PM-932M-PDF w/3 axis DRO. Yes it is available with X axis Power. I wish I could give you more info about the machine but I haven’t fired it up yet. But, I can honestly tell you that if you got a PM 932 you would most certainly want the power down feed. I played around with raising and lowering the head and I can tell you it was a lot of work. Being a machinist as a profession I can tell you that I would rather have a geared head mill rather than a variable speed bench mill. The geared head is so much more versatile for a variety of materials. Variable speed may be great in aluminum but once you try milling Steel you’ll wish you had more power and more rigidity. Just my opinion tho.
Skowinski said:
Thanks again for all the help everyone. I've decided I don't need a larger knee type mill, and really the 932 may be a bit of overkill for me. I've narrowed it down to the PM30MV and the PM932M now. It looks like the 30 doesn't have power downfeed and the 932 doesn't come with the powered x-axis drive (or, I'm not seeing it on the website at least...). I like the idea of having a variable speed control and x-axis drive on the 30, and not sure I'll ever need the power downfeed on the 932.

Leaning towards the 30 at the moment, it's probably all the machine I'll ever need. I'll wake up one day soon with a decision I'm sure.
Click to expand...
 
I have the PM932M-PDF w/factory DRO, about a year now. Unless you get the basic model it comes with both power X and Z (head lift). That’s not the same as PDF, which drives the quill, primarily for boring operations. I’ve been pleased with mine.

If you expand the description on the website it will show the options.
 
I appreciate the comments and ideas, thanks!

I did notice the 932 has X-axis power feed, in fact confirmed with Matt what I read in the detailed description - all but the 932 Basic come with the X power feed, which is a plus.

The more I read the more I think I'd rather have a geared head machine.

Still haven't woken up one day with a decision, LOL...
 
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