Friday, September 10, 2010

Hey, I got to do something for me again!

If you've been following my blog, you'll remember when I posted pictures of my Harper & Reynolds lathe when Part-timer Steve and I moved it from his garage in Boulder where I had it stored, to my place. One of the things that needed to be re-manufactured was the framework that held the lathe motor and drive pulleys.

In the above photo is what originally came with the lathe. It was done decades ago when it was converted to electric power, done pretty crudely, weighed a ton, and had a lot of flex in it. In between bike work for everybody, I've been making parts for the new one when I could grab a few minutes, and I finally got some spare time to weld all my components together.
Here's my new framework to hold both the lathe motor, and the drive pulleys. I wanted something that was strong, and "fit in" design-wise with the age of the lathe itself. The sides are 1/4" steel plate that were a little narrower than I needed. I welded two sections of plate together, made a full-sized posterboard pattern for the plate's shape, then traced it on the plates with a soapstone.

I was going to cut them out with Dennis Goodson's plasma, but it was on the blink, so I cut them out with my torch. Let me tell you, it's been a long time since I've cut plate this way, and it took me a while to remember how to set my bottles to do it! But, they came out great, with little "kerf" to smooth out afterwards.

The main crosstubes are 3/16" wall x 1 3/8" dia. DOM tubing, and the front crossbrace tube is 1/8" wall x 7/8" tube. The uprights were done in 3/16" wall x 1 1/4" square tube that I fishmouthed to fit around the 1 3/8" main tubes. The pulley and motor mounts were made out of 2" x 2" x 1/4" angle iron. I TIG welded the whole thing together. This new framework is actually lighter than the old one, and there isn't any flex to the framework at all. I met all three of my goals - weight, strength, and style - and I'm pretty happy with it!

I have the pivot tubes cut that will go on the ends of the sideplates (you can see the cuts in the plates for them), that will actually mount/pivot the frame on the back of the lathe, but I didn't get a chance to weld them on before I took the photos. I'll post up pictures with the whole thing mounted on the back of the lathe, so you can see exactly how Harper & Reynolds mounted the steam-driven pulleys when I'm finished.

Before, the lathe motor sorta flopped off the back of the framework on two sets of ancient heim joints bolted together, using the lower two motor mounting pads. The weight of the motor "kept" the drive belt in tension. Now, the motor bolts on the framework with all four of the motor's mounting pads. The motor's new mounting plates are slotted, so to tension the drive belt, all I'll need to do is slide the motor down, and tighten it in place with its four 7/16" dia. mounting bolts.

Once I get the frame's pivot tubes welded in place, I can mount the frame to the back of the lathe, and figure out the new length for the primary and secondary drive belts, and head for Western Belting here in town, and have them shorten the secondary belt, and make me a new primary belt 1 1/4' longer than what I have. Lucky to have a place locally to do this - as Part-timer Steve always says "Where the fuck do you FIND all these places?". Well, over the decades, you amass a pretty good file of business cards for hard to find things just like these belts - and craftsmen like Dennis Goodson, Rick Labriola, and Bob Schencks have passed along their sources to me as well......

But, Don't tell Steve, he thinks I'm like a Yoda or something......OK?

1 comment:

Noot said...

Never throw away a business card . . .