PDA

View Full Version : Need some ideas please....



Joe Suelter
02-12-2003, 10:34 PM
My Brother just aquired a 1950's Sears lathe. I couldn't find a picture of it on the web, so please use your imagination. The lathe is in fairly decent shape, a little surface rust, but very workable for his first lathe, and can't beat the price! The problem is, the induction motor is junk, won't run at all. I have 4 spare 1/3h.p. motors lying around, so I figured I'd give him one of those. Here lyes the problem, the original motor is bolted to the stand, with no adjustment for the belt. I would like to build something (cheap) that would allow belt tensioning, but am at a loss for ideas. The motor is bolted directly to the stand, with the pulley facing away from the lathe (pulley facing left as you stand in front). There is nothing wrong with the way they have it, but it makes changing speeds a little difficult. I thought about mounting the motor to a piece of 3/4 plywood with a hinge at the back, and another smaller piece of 3/4 plywood mounted to the stand, but the problem I see is the motor would then be resting on the tension of the belt...bad for bearings?!? I know this sounds like a weird question, but I'm dumbfounded as to a good idea. Thanks in advance!--Joe Suelter

Bob Lasley
02-12-2003, 10:57 PM
Joe,

My old lathe has the motor mounted much like you describe how you are thinking with the hinge setup. It has been that way for years and the bearings are fine. I would go for it.

Good luck,
Bob

Joe Suelter
02-12-2003, 11:03 PM
Thanks Bob, I guess I'll give it a shot. One quick thought I forgot to mention, if we get a belt that is a little long or short, the pulley's will be slightly out of alignment, wont they? I suppose I could get him to cough up the big bucks for a link belt, then we could tailor it to the right size, I think I just answered my own question:cool: ! Thanks..

Bob Lasley
02-12-2003, 11:07 PM
Joe,

I don't think the belt being a little long or short will matter, but I would recommend the link belt (I don't have one on my lathe right now, but soon will have) as regular belts are bad about taking a set when they sit for awhile and will cause vibration.

Bob

Bill Grumbine
02-13-2003, 8:27 AM
Hi Joe

Iused the hinge flap thing for the motor on my Vicmarc mini, and it was a royal pain. Something in the way it worked caused an extraordinary amount of bouncing on the part of the motor, and I could not get it to work right.

I took it apart (my homemade mount, that is) and rebuilt it so that the motor was mounted on a flat piece of plywood, whcih was attached to the inside of the cabinet with dovetailed ways. It eliminated 100% of the bounce and vibration, and with a slot in the cabinet for a bolt to tighten it down, I was able to ensure constant tension on the belt, plus make it very easy to change speeds.

Good luck with it.

Bill

Rod Dilyard
02-13-2003, 8:43 AM
Your idea for mounting the motor on a hinged plywood support is a good one - just put the hinge parallel with the motor shaft, not at the back end. That way the pulleys will stay in the same plane regardless of the tension. Use a couple of long bolts with double nuts (so they don't vibrate loose) to set the belt tension.

Hope this makes sense - let me know if it doesn't.

Ted Shrader
02-13-2003, 10:32 AM
Joe -

The hinge method as you described was the first thing that came to my mind. However, Bill's idea about having the motor down in the stand on ways sounds pretty good. May be worth the effort to execute something like that. The added advantage is the stand which you can load full of sand bags in the bottom to help reduce vibration.

Good Luck,
Ted

Kyri
02-13-2003, 1:38 PM
The hinge concept can work but I don't think you will be very happy with just the motor putting tension on the belt. Maybe use a bolt to place tension against the plywood base? Also a 1/3 hp motor is a little on the light side for even a mini lathe.

Hovey

Tom Sweeney
02-13-2003, 2:45 PM
<p align="center><font size= "3" color="red"><B>Have you ever seen how a car alternator is installed?</B></font></p>

<p align="left"><b>You could mount it on a hinge & then put a peice of iron with a slot in it then run a bolt through the slot to the motor. You loosen up the bottom bolt hinge & the bolt in the slot then you can adjust it.</b></p>

<p align="middle"<font size="4" color="brown">Jee that's as clear as mud isn't it:rolleyes: </font></p>

<p align="center><font size= "3" color="red"><B>look at your cars alternator & see what I mean. </B></font></p>:confused:

Joe Suelter
02-13-2003, 6:55 PM
Well, I have seen MANY alternators in my days of turning wrenches, but the other point I left out was that the belt goes through a hole in the casing of the lathe, so that's out, unless I get fancy.

I agree that a 1/3 h.p. motor is a tad weak, but that's what was on it, and he's only learning, never turned anything before. I would rather have the motor stall that have the gouge ripped from his hands, he's a police officer by day...just getting into woodworking.

Bill, your idea turned on a few bulbs in my head...I'm headed to the shop in a little while to hopefully implement them, or a similiar fashion!!

Thanks to everybody for your help. We'll make it work, this is only temporary anyway, just to get him hooked so he can buy a better lathe & tools...then it's payback time!:p --Joe Suelter

Scott Purdy
03-06-2003, 1:50 AM
I've done what Rod suggested with an old Craftsman joiner and stand that I bought a few years ago. The joiner is circa 1972 but had never been used until I put it together. All of the parts were there except the hinge and plates, and I made one from 3/4" plywood and some metal hinges I had lying around.

Originally, I used a quickclamp to put some tension on it, but the clamp fell off once while I was moving the joiner, I used the joiner without the clamp, and gravity worked fine (I do have a link belt on it).

Not sure if that info helps in your case, but a gravity-held, hinged motor plate with the hinge in the same plane as the motor drive worked well for me on a joiner.