# NEW PM 2 X 72 BELT GRINDER   (sort of)



## Muskt (Jan 25, 2017)

Here are several pics of my new PM 2x72 belt grinder.  Well, at least it is the correct colors, & uses the motor from my PM 1236 lathe.

Anyway, it was a lot of fun to construct, & it still needs some tweaking; but it runs and cuts great.  (Video at the end of the post.)

Some info on the parts used:

1.  The front end, consisting of the large piece with the 2 rollers, the platen,  & the black tracking roller were purchased from OregonBladeMakers on EBay.
2.  The Blue pieces were scrap 2 inch box tubing.
3.  The White pieces & the shiny pieces were Stainless from the local metal yard.  Side note:  The small tubing only required small amounts of grinding (milling) to fit inside the larger pieces.  There is NO seam inside the tubing.
4.  The switch box & switch was purchased at my local Ace.
5.  The large pulley on the motor was also purchased at the local metal yard.  It is 7.5 inches in diameter.  With the placarded RPM (1410) of the motor, that results in approximately 2700 SFM on the belts.  (A bit less than desired.)
6.  The motor was "re-purposed" from my PM 1236 lathe.

All the welding was done with TIG.

Here is a link that provided the inspiration and basis for this grinder.

http://dcknives.blogspot.com/p/2-x-72-belt-grinder.html

I have not tallied up the cost; however, I can estimate that the purchased items came to the ballpark of $250 (not counting belts).

OK, enough yammering.  Here are the pics & video.

Jerry in Delaware


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## Bray D (Jan 25, 2017)

I have a PM 2 x 72 also! 100% machined. I made everything except the machine components. If you haven't had one before, you'll love the additional shop capabilities. I use mine on nearly every project.


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## sanddan (Jan 25, 2017)

Great job you guys. I have a single phase motor off my PM1340GT that I plan on build a grinder around, another project on the list.

Bray, can we get some more pictures of yours? Looks beefy!


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## mikey (Jan 26, 2017)

Thanks, Guys! This has now moved up near the top of the To-Do list. The ready availability of the wheels at a reasonable price is awesome. Now I don't have any more excuses.


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## lpeedin (Jan 26, 2017)

Did you guys make your own rollers?  Would love some detailed pix of them. 


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## Bray D (Jan 26, 2017)

I don't want to hijack Jerry's thread, but here's some more info on my grinder. Feel free to shoot me a message if you want any more details. 

100% bolt together frame made from 1/2" steel. Machined everything on my PM932M. I purchased the rollers, bearings, handle, motor, belts, etc. I purchased my small wheel attachment for tube notching also. The platen is aluminum. I cut the profile on my machine with a rotary table, then had a buddy of mine polish it for me. 

A 2hp WEG motor drives a 4" drive roller through 2-3-4 pulleys. My belt speeds pretty much match the Beaumont grinder at 900, 1800, and 3600 surface ft/min. 3600 is sufficient for general fab. The slower speeds will be nice if I ever get into knifemaking, but I rarely use them now.


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## Muskt (Jan 26, 2017)

I have no problems with anyone contributing to this thread.  It is about grinders for the shop.  More ideas = better grinders.

Jerry in Delaware


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## Bray D (Jan 26, 2017)

If I had to build another one, I would definitely make a welded frame design. I wanted to do a no-weld frame this time just to get more experience on my machine. I have close to 40hrs of machine time into mine, and more money than I care to talk about. Still cheaper than buying from Beaumont though.


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## lpeedin (Feb 4, 2017)

Got my rollers machined today & the bearings installed. The roller in the middle has a 3 degree crown. 
	

		
			
		

		
	







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## Muskt (Feb 5, 2017)

Here is the finished grinder.  Quite a bit of work; but, a great addition to the shop.  The base is massive--lower tubes are 2.5 OD with 1/4 inch thick walls (for weight & stability)--the upright is 4.o OD 1/8 inch walls.  Best guess is that the base weighs around 75-80 pounds.  The whole assembly is probably around 150 pounds.  In order to "level" the base and preclude any rocking action, I drilled & tapped the bottom tubes 1/2 x 13 & used Grade 8 bolts with a jam nut.
Since bolt heads are not flat,  I put them in the lathe and turned the heads flat, then I decided that a shallow taper with a point would be good.
So I turned about an 8 degree bevel on them which left a point to dig in to the concrete floor just slightly.  Works great--no vibration, no sliding around.

Some dimensions---Base is 34 inches (front to back), 24 inches wide, and the tool rest is 45 inches from the floor.  The tool rest seems to be an OK height for me (5 foot 8 inches); but, for heavy pieces, it may prove to be just a bit too high.

Anyway, I'm very pleased with how it turned out.  BTW, the steel for the base cost me $48--so an estimate for the whole thing is in the neighborhood of 
$250.  Remember that the motor was re-purposed from my 1236 lathe.

Jerry in Delaware


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## dieselshadow (Feb 5, 2017)

Dadgum.... You had me going here. I thought Matt actually had a belt grinder that he was selling. I was about to whip out the ol' credit card and click "order now."

Nice job! Want to make another one?


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## Groundhog (Feb 5, 2017)

Nice work guys. Something for me to keep in mind for a future build.


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## rwm (Feb 5, 2017)

Awesome work on both of these. Bray- that looks very heavy duty. Did you design this on CAD, paper or gray matter?
Robert


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## Bray D (Feb 5, 2017)

I'm a CAD guy. I operate in SolidWorks all day at work and have Fusion360 at home. Both excellent platforms. This one was done in SolidWorks.


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## rwm (Feb 5, 2017)

If you put the details in the "plans and drawings" section I will be building that when I get a larger shop!
R


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