I needed to slow my drill press down to be able to saw 2" - 3" holes in 3/16" - 1/4" steel so I wanted to get the spindle speed down to around 150 RPM. I didn't want to go the VFD route so I looked into one of the drill press speed reduction pullies offered on this site by JZiggy but a single step pulley wouldn't get me as slow as I wanted. I wish it would have - it looks like an outstanding product and a steal at 200 clams! I wound up making a double step pulley setup using pullies from Chicago Casting which I fitted with oilite bushings from McMaster-Carr. I machined the shafts from A2 tool steel rod, also from McMaster-Carr. With the current belt configuration with a 1725 RPM motor I have a spindle speed of 240 RPM. I ordered a different belt for the last reduction to get it into the smallest drive pulley and the largest head pulley, and with that it'll be somewhere around 170 RPM, as good as it gets for this. It's easy to remove the assembly and replace the original belt to make it as it was for normal drilling. Hopefully, it'll work well for hole saws and larger drill bits and be worth all the work and expense!
Slowing down my drill press
- Thread starter olddog1
- Start date
As the great Project Farm would say
"Very Impressive!"
Was not expecting to see such a well executed spindle reduction fab job, these threads typically don't get much further then asking if they can put it on a potentiometer....
Good luck with the project keep us posted on how it works
"Very Impressive!"
Was not expecting to see such a well executed spindle reduction fab job, these threads typically don't get much further then asking if they can put it on a potentiometer....
Good luck with the project keep us posted on how it works
nadogail
Well-known member
Save your original pullies for possible reuse or restoration.
Thanks. Good advice. The original pullies stay on it. I just added two 4-step pullies between them. I can lift the 2-pulley assembly off and re-install the original belt when I'm done with big holes.
Renegade1LI
Well-known member
That was a good solution but you really should have replaced the dp. A 3ph powermatic 1200 with a reeves drive or similar plus vfd would have been the correct solution.
Bill Wright
Active member
- Joined
- Jan 22, 2017
- Messages
- 44
Great job!
what is the piece you used to mount the assembly to the drill press mast?
was it off the shelf or something you made yourself?
thanks
Bill
what is the piece you used to mount the assembly to the drill press mast?
was it off the shelf or something you made yourself?
thanks
Bill
Thanks for the compliment. It was just a cast iron two-groove pulley with a 5/8 bore that had been in my pile of do-dads for decades. I just turned it down on the lathe to fit the inside of the column and ran a 5/8-18 bolt up through it to attach the pulley mount. Sometimes even a blind squirrel finds a nut!
I'm just a home shop and for the amount of this work I do, what I did is plenty correct enough. Thanks for the input, though.
nadogail
Well-known member
At a former employer we had a need for a hole in an inconvenient area. We bought an inexpensive Harbor Freight drill press and swapped out the driven pulley with a 11 inch hardware store pulley and for only a few dollars avoided the purchase of an expensive magnetic base drill press.
Our work around was lighter and more convenient than a “Mag Base”.
Our work around was lighter and more convenient than a “Mag Base”.
A great fix!
knobby
Well-known member
Well executed, my OCD approves.
I agree!
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Nice!
Thank you for the compliment! Where would I find such a motor?
Ultradog MN
Well-known member
Or...
If you're gonna go 3 phase maybe getcha a Solberga.
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Renegade1LI
Well-known member
Always have my eye out for one
Me too, but they tend to run about twice the price of a Powermatic 1200, and are pretty rare in my part of the country.
Today I received the belt I needed to run this in the slowest position and the spindle speed is now 148 RPM according to my idiot-proof Starrett tach. It sawed a 2-1/2" hole in 7/32" steel without any hesitation whatsoever. I'm very happy with the result. It's not one the more sophisticated units that were posted, but for my purposes it'll be just fine. I appreciate all the comments and information! Thank you guys.
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They are available locally as well as on the auction site. Fairly popular on agricultural equipment.
My buddy gave me one for my VS drill press. My lowest speed is now about 200 rpm
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RTM
Well-known member
Most logical from here
Thank you. That's good to know. Next time! That's a nice drill press!
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bugzilla46310
Well-known member
Any problem maintaining belt tension?
Not so far, but I only have about 30 minutes' time on it. I don't expect any problem with it. The two shafts are only about 3" tall and are secured with 3/8-16 nuts with thick area washers over and under the slots and the motor adjustment is original and pretty robust. It's hard to get it to move when it's loosened!
JuncleJohn
Well-known member
Nice work modifying your drill press.
John
John
Thank you! I appreciate it.