"How Would You"... Pulley for PowerPro takeoff

nuhobby · Post by **nuhobby** » Mon Mar 03, 2014 12:39 pm

Greetings,

As a diversion during my last machinest-chest project, I got a derelict, very small metal-lathe.... free from my brother in-law

:

[ATTACH]24240[/ATTACH]

I have gradually been cleaning it up and I just lately installed a new, straight spindle. I'm aware that the Craftsman/AA/Dunlap 109 isn't the finest lathe in the world, but I think I'll like it for occasional small-time projects.

One thing that is missing is a Motor. I've spied a 1/3-hp unit I could use in a local antique mall, but even there I've read that a typical 1750-rpm motor with the 3-step pulleys runs the 109 lathe a bit on the too-fast side. SO.... I'm wondering if I shouldn't just drive a belt from my PowerPro headstock to the 109-lathe on a roll-up table. This would let me go as slow as 250rpm straight-out, and 5 times slower if I engage the back-gear on the lathe.

Questions I have for you guys are:

(1.) Is a pulley on the Powerpro quill or back-side spindle-end OK? I'm thinking of using a link-belt over to the metal-lathe. Any good sources for a pulley? And a belt?

(2.) Or would approach (1.) cause too much side-load on the Powerpro/Quill bearings? Would I be better off to "hang a pulley" between the Quill and the Tailstock-center of my Shopsmith? Any idea what sort of parts/bearings to use for that?

Thanks in advance.... and stand by for updated pictures in the weeks coming up!

Ed in Tampa · Post by **Ed in Tampa** » Mon Mar 03, 2014 2:29 pm

My thought is why chance it. Build a jackshaft assembly that can be connected rock solid to the bench tube or carriage and connect it to the SS power with the SPT power connector. Then you would have no side load on the SS and depending on how you built it probably an easy connection the to the SS.

I never like to place a side load on a bearing I can't easily see and replace. Even though most are well up to the task.

I'm thinking a simple frame that can be connected the bench tube. Two bearing blocks and caps, a shaft and pulley. At the end of the shaft mount a SPT connecting hub. Then using a power connector connect to the SPT hub and you are good to go.

JPG · Post by **JPG** » Mon Mar 03, 2014 3:08 pm

Ed in Tampa wrote:My thought is why chance it. Build a jackshaft assembly that can be connected rock solid to the bench tube or carriage and connect it to the SS power with the SPT power connector. Then you would have no side load on the SS and depending on how you built it probably an easy connection the to the SS.

I never like to place a side load on a bearing I can't easily see and replace. Even though most are well up to the task.

I'm thinking a simple frame that can be connected the bench tube. Two bearing blocks and caps, a shaft and pulley. At the end of the shaft mount a SPT connecting hub. Then using a power connector connect to the SPT hub and you are good to go.

I like Ed's idea! It could be made out of 2x4's. 4 vertical posts that rest on two horizonal pieces that rest on the bench tubes, 2 horizontal pieces that rtest on the way tubes, two horizontal pieces that mount the pillow blocks or some other bearing and the pulley and shaft. A couple of clamps below the bench tubes(ala speed reducer/increaser/planer/lathe duplicator.

Harbor freight has link belts(house brand)[link belts only work one direction].

Not only would a pulley on the headstock shafts place a side load on the shaft, it also puts a twist.
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nuhobby · Post by **nuhobby** » Mon Mar 03, 2014 3:30 pm

Ed & Red,

I have been attracted to your ideas, basically making the metal-lathe's spindle an extension of the PowerPro's spindle....

The main compatibility challenge there, is that the "109" metal-lathe's spindle will have a gear on it, the very upper gear shown in that picture. That gear drives the rest of the gears if one is using "threading" or "power-feed" features. That gear occupies the whole length of the exposed spindle. So an 'adapter to the Shopsmith' would have to duplicate those gear-teeth.

On the other hand, if I run a belt to the pulley inside the 109-lathe's headstock, I can preserve all the 109's features: power-feed, threading, and back-gear 5:1 reduction.

Hoping to find the best of all worlds....

reible · Post by **reible** » Mon Mar 03, 2014 5:02 pm

Keep in mind ball bearings have about the same ratings in thrust and axial directions, just happened to remember this from our class in bearings so many years ago......... I bet I still have to book up in the attic unless something ate it.

Seems to me we have seen a lot of small variable speed DC motors (sewing machine) that would serve this application well. Might want to take a quick look at that as then it would be self contained. Not so much for getting oil and metal chips near the shopsmith unless it has to happen.

Ed

Ed in Tampa · Post by **Ed in Tampa** » Tue Mar 04, 2014 11:52 am

reible wrote: ... Not so much for getting oil and metal chips near the shopsmith unless it has to happen.

Ed

MOST EXCELLENT point!

nuhobby · Post by **nuhobby** » Tue Mar 04, 2014 2:57 pm

I sprung for the $27 used Craftsman induction motor at the antique-mall at lunch-hour today....

If I try that and find it to be too fast, I'll probably look into a variable-DC approach or something else. $27 isn't much compared to what I've spent on the spindle.... not much compared to a couple of quarts of Evaporust for that matter

.

sawmill · Post by **sawmill** » Tue Mar 04, 2014 3:55 pm

I had the same lathe. I bought it from a guy at work and the motor that was on it turned at 1050 I think. The motor went bad and I put one on it that was 1/3 hp 1725 RPM's. It turned to fast to cut threads but worked good for polishing parts. You may be able to rig a jack shaft between the motor and lathe to change the speed. I traded it for a new in the box ShopSmith scroll saw