# Convert bench grinder into disc sander?



## Burnt_Blade

Just wondering if anyone has done this...I was thinking this might be a useful thing to do and save the money of buying the separate tool.

Would have to figure a way to mount a plywood or mdf plate onto the shaft of the grinder. As well as some method of applying the paper to the plate in a way that it can be changed.


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## woodnthings

*The right and left threads on either side could be*

a problem. A better idea might be to get a replacement part from a combo sander, like Craftsman, Jet, etc. and just use a motor shaft, no threads.
I made my own that way:
http://www.woodworkingtalk.com/f2/homemade-disc-sander-11668/
Grizzly has a 9" cast iron sanding disc: http://cdn4.grizzly.com/manuals/g1014z_m.pdf
Part no. P1014021 Maybe you can order it?
They also have a 12"disc: P7297025


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## Jacktoo

nice job woodnthings


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## jlhaslip

what sort of horsepower is the motor?
I have a motor from a dryer. Will that do it?


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## woodnthings

*A dryer motor is 1/3HP*

If I recall from my days of "picking" stuff off the roadside. Usually with a 1/2" shaft. This will do....but is not the best motor for that application. Mine is a 3/4 HP totally enclosed version. It takes a fair amount of power to get that heavy 9" cast iron disc up to speed. An aluminum disc like they used to make and sell would be a better choice for a smaller motor if you can find one. A clever guy could make one from a
"V" belt pulley that fits your shaft size and attaching an aluminum plate to one side. Getting the thing concentric and free from "wobble" will be the biggest challenge in a home made disc. HF sells self adhereing discs in 9" and 12" sizes for this use. The smaller motor will be fine for the hobbiest, but not for serious woodworking. JMO :thumbsup: bill


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## Walter_Lars

shop notes or woodsmith had a articale about making a DIY floor mount disc sander IIRR theys had two bearing blocks to steady the shaft like 10 " apart motor mounted below the shafts in a box sealed away from the dust with a pully on the opposite side of the disc and a the belt going in a slot down do the motor I will see if I can find the article this may become a very complcated project have thought about just mounting a hand held belt sander in a wooden base up right


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## Burnt_Blade

Walter_Lars said:


> shop notes or woodsmith had a articale about making a DIY floor mount disc sander IIRR theys had two bearing blocks to steady the shaft like 10 " apart motor mounted below the shafts in a box sealed away from the dust with a pully on the opposite side of the disc and a the belt going in a slot down do the motor I will see if I can find the article this may become a very complcated project have thought about just mounting a hand held belt sander in a wooden base up right


I have the article in ShopNotes for building a disc sander...it does look to be a very involved project, so it always found its way to the back burner...lol. I just thought converting a cheap bench grinder would be easier way out. Thanks for offering to look though.


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## Walter_Lars

I have tryed small disc sanders and have not been happy with them 
they ether too small of a disc size or don't have enough Ummph to not stall out as I am shapeing a part 

A heavy sanding disc might over come that to act as a flywheel effect 

its a fine balance between power/torque of motor and weight of sanding disc ​


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## cowboy dan

jlhaslip said:


> what sort of horsepower is the motor?
> I have a motor from a dryer. Will that do it?


an old friend had a furnace motor hooked up to his really old tablesaw so a dryer moter should work for a sanding disc. i would use thread locker incase your disc isn't balanced


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## fozzy767

im currentnly making a 12 inch sander from a grinder,local machinist is making the alumimum disc.thought about using both sides.obviously the other shaft will turn opposite so im in the process of figuring a way to use other shaft.i may just cut it off


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## Walter_Lars

obviously the other shaft will turn opposite so im in the process of figuring a way to use other shaft.i may just cut it off

just put a fench on it and use it just remeber it turns back wards 
make one disc 50 or 60 grit and make the other one 120 grit 
presto two disc sanders :thumbsup:


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