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I have a number of plans for one of these , but they require a 1 hp 1750 motor. Have 2 older 1/2 hp motors but not sure if they will work? . anyone have experience building these machines? . Signed, tired of driving the bus. PS I made a simple jig that runs off the drill press but dont like it . Prefer a dedicated machine

I just made one earlier this year. I made it mostly from junk I had available. That meant I had to use the motor from an old clothes dryer. That motor is. Retail you less than 1 hp, probably 1/3 hp or maybe 1/2.

I’ve only used it on 1 guitar but it performed okay. I couldn’t stall it if I really lean on it, but you should not be doing that anyway. Leveling a rim with solid linings went from a tedious chore to pretty simple. Now the most annoying part of the task is getting the machine out and putting it away.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Hi Ernie,

Mine uses a 1/2hp, 1750 motor. I used a 1-1/2” to 14” pulley setup so it’s got plenty of torque. You’d never be able to stall it -

So quick!

M

I used a two speed washing machine motor rated 1/6 hp at the 1130 rpm slower speed. The 20” pulley is made of ash. The motor pully is 1.5 “. I made it as compact as I could for storage and clamp it to my workbench when I use it. Not only does it make my work easier, it does a more precise job of sanding since there’s no change of direction in sanding.

Dowel holes in the bottom of the dish line up with dowels in the big pully. The resulting speed is about 85 rpm on the dish which works quite well.

I went to Harbor Freight and bought a cheap 4" x 36" belt/disc sander and "harvested" the motor from it. 3/4 hp, 1750-ish RPM. $80, plus tax. And it comes with a little pulley, a short belt, a power cable and on/off switch, as well as some junk to throw away or recycle. Get the right pulleys and shafts to reduce speed, and you're in business. I can stall mine, but it takes some bearing down, and I don't really bear down. I just let the 24" disc do the work. If you run a search on my ID here on the OLF, there are links to my sander. The current version works GREAT!

Don . Looked all over for the plans . Could not find them tnx. Bob do u have more pics of your sander ???. How is the wooden pulley mounted to the radius dish TNX

Here is a link to the thread with details about my sander, Ernie:

viewtopic.php?f=10101&t=51545&hilit=Motorized

I need to take the plunge and build something. Some great solutions here.

I’ve had a notion to rig up a dish sander close by the buffing arbor so they can share the one motor. Space is always at a premium. If I could get my buffer to run slow enough I’d try just mounting a dish on the shaft. At 700-some RPM a 24-inch dish is a bit terrifying.

I recall Bruce Sexauer had a nifty solution driven by his drill press too. That’s an appealing route.

A half horse power motor should work fine. I cobbled together a couple of sanding dishes using a bowling ball balancer and also one using a food processor. The food processor has three speeds and an easily removable dish, so it is easily stored when not in use.

TNX everyone for pics , advice an suggestions, it is much appreciated. Off to the shop to find parts. Bob how did you connect the ash disc to the radius dish PICS ?? i have a long 1/2 in bar stock and 3/4in tnx

Ernie, the wooden pulley has a couple of 1/2” holes that line up with a couple of holes in the bottom of the dish. Dowel stubs in those holes connect the pulley to the dish. The pulley rides on a 12” lazy susan bearing. The bigger holes in the pulley allow access to screw the bearing to the base. The noisiest part of the operation of this device is that bearing. I cheated with the motor mount and stole a piece off of an old furnace fan. One side of the motor mounts to a bar that can rock along its long axis. The other side is a tension adjustment bolt that pushes against the mounting surface. If you still want more pictures, I can do that later today.

Tnx so much bob. I live out in the country, so its off to homeless depot for a 1.5in pulley.. Yes more pics would be appreciated Thank you

These should show most of the features. I put the handles on while I was photographing, so they are in some pictures, not others. The photos didn’t land in the expositionary order that I intended, but the full design ought to be obvious.

Note the rudimentary belt guard. The belt made me nervous, so I covered it to keep it from easily being touched.

I put off making this for years. I should have done it a couple of decades ago. It had to percolate until I had a design I liked. I’ve done a few guitars with this now. It’s a big help.

The lazy susan bearing was pretty cheap from Amazon. I figure if it wears out, I’ll get another or find something else.

Bob does the lazy susan sit under the ash pulley ? how did you rout a groove on the ash pulley . Have some white oak for one . Just checked 1/2 hp motor working TNX> !!!

The lazy susan sits between the ash pulley and the base, screwed to each. I don’t remember exactly
how I cut the belt groove. I remember I thought about it for a long time before I did it. I reviewed my router bit collection. I don’t have any wing cutter bits that would have done it from the side, so I must have cut it with a straight bit, fence guided, with the router shaft at right angles to the plane of the disk. Don’t trust me on that. Do some experimenting on something less valuable than the big disk you make. It appears that I let belt friction round the edges of the slot.

The base is made of glued up 2 by lumber. This was one application where I used Titebond instead of HHG.

When I built it, I went through my old motor pile to find one with a low speed. Most AC motors tend to be around 1750 or 3400 rpm. 1750 would require big pulley differences to get the rotational speed down. 20” seemed to be about as big a pulley as was practical (and about as much ash as I had). The species wasn’t important. It just had to be a hard wood and not some of my precious quartersawn stash.

After I mounted all the pieces, I measured and ordered the appropriate belt from Amazon.

Tnx bob , was just rummaging through my bits as well . I/ve got 1/2 in core an v bits, so will have to figure that one out . My motor is 1750 / 1/2 hp ordered a 1,3/4 in steel pulley from amazon. I have also ordered a momentary foot switch . I have 2 of those 12 in L susans mounted under my radius dishes so will take em apart. We have a local oreilley auto parts , so we can get a belt from them, Since i/m using a momentary foot switch I dont mind a faster speed over 150 rpm. TNX for the explanation