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russell lusthaus
03-16-2010, 6:10 PM
Hi all:

Recently went to Colonial Williamsburg with the family and I think I had a better time than the kids. Anyway, in the joiners shop, they had a treadle lathe which the guys let me pedal on for a couple of minutes. Not to turn anything, just to check out the motion. I am hooked. Since then I have been looking around for plans etc so that I can build one for my shop. The wood working seems pretty straight forward - I am sure alot of tinkering will be called for with the pedal and the linkage.

My question relates to the non wood working portion of the machine - the bearings and the shaft - mechanics not being my strong suit. The plans I have seen (mine will be a combo of many different plans) call for a shaft (say 5/8 drill rod) to pass thru 2 bearings as well as / or terminate in/at a thrust bearing.
Questions:

Does the shaft go thru the thrust bearing like regular bearings or just end at and butt up against the thrust bearing?

Does the thrust bearing get secured to the shaft?

Other than stop collars on the shaft, is there another way to limit the shaft from running thru the regular bearings (assuming the thrust bearing does not lock onto the shaft)?

Is there a method of securing the bearing in the wood other than a press fit in a hole, or is a press fit good enuf?

Lastly (for now), what type of inboard end would be most preferable on the end of the shaft (threaded, smooth shaft, etc?) and is there a way to get a MT adapter on the end of the 5/8 shaft?

Where should I be looking for bearing and shaft supplies?

Thanx in advance for the help.

Russ

Gary Radice
03-16-2010, 8:06 PM
I'm sure others more knowledgeable than I will chime in, but some small pillow blocks with stop collars would probably work. Mcmaster-Carr would be a typical source online.

You might also ask over at owwm.org. There is a thread going on now about shop-made machines in their SWARF forum.

Jerry Bruette
03-16-2010, 8:35 PM
Russell,

I'm guessing that you could spend some time over at the SKF website. They manufacture bearings of all sorts.

Depending on how much thrust you'll develop you could probably use what's called pillow block bearings, they'll handle some thrust but are by no means a "thrust bearing." You can defenitly use pillow block bearings for the shaft to pass through...that's exactly what they are designed for. I would highly reccomend what's called cam lock and not the type that secure with just set screws into the shaft.

You might also rethink the size of the shaft, 5/8" seems rather anemic to me. You'll be putting a side load on the shaft while turning and I think 5/8" might deflect. I'm thinking more like 1" to 1 1/4" would be better and you might get deflection with that, depending on how much is hanging out of your front bearing.

I would also reccomend that you run your drive belt between the two bearings to keep any deflection to a minimum.

Good Luck:)
Jerry

Milind Patil
03-16-2010, 9:12 PM
There are many web sites with huge selection of bearings. Try www.vxb.com (http://www.vxb.com) They got a very wide range of products.

Chris Padilla
03-16-2010, 9:20 PM
You should speak with George Wilson...look him up.

Peter Stahl
03-17-2010, 1:42 AM
Do a web search for Tredle lathe, lots of info out there on how to build one. Unless I stop getting electricity at my house I don't want to tredle anything but that's just me.

Russell, Was there anyone doing any real woodworking when you were there. When we went they just pretended to hammer stuff.

russell lusthaus
03-17-2010, 12:52 PM
Thanks for the leads guys, I will follow up.

I agree that the belt should go between bearings.

I also agree that 5/8 sounds a bit flimsy for a shaft, but all the plans I have seen use 1/2 and they all comment or recommend that you use 5/8. Still cannot figure the best end for the shaft (threaded or not, or something else) no matter the diameter.

Peter - no, they were not really doing any real work, and the streets were empty, so the guys had plenty of time to shoot the bull.