Bicycle wheels as pulleys?

[websterz]

I am amassing the materials needed to build a 12" power hacksaw. To bring the motor's speed down and increase torque I plan to use a 2"-12"-2"-12" jackshaft assembly. This should yield 60-90 strokes per minute, right where I need it. 12" pulleys are rather expensive, 2 of them are doubly so. My daughter is willing to donate her old bike for the project. Sans the rubber bits the wheels measure the required 12", have wonderfully rolly bearings, and are free. Has anyone used wheels as pulleys before? The saw will only be used for light cutting duty with regular 12" blades. Am I just being TOO cheap?

[John Hill]

I cant see why that would be a problem although I feel I would be more inclined to turn a wooden pulley or two, because:
a. It would allow me to get the proper profile for the belt I would be using.
b. It would be an excuse to play on my lathe.

Bicycle wheels are not very strong in the side load direction but that would not appear to be a problem for your project.

[websterz]

I cant see why that would be a problem although I feel I would be more inclined to turn a wooden pulley or two, because:
a. It would allow me to get the proper profile for the belt I would be using.
b. It would be an excuse to play on my lathe.

Bicycle wheels are not very strong in the side load direction but that would not appear to be a problem for your project.

One problem...hard to turn a 12" pulley on a 7" mini-lathe.    If I had enough swing for a part that size I would make them out of some 1/2" aluminum plate that is sitting in the corner looking for a purpose in life.

I was planning on using flat link belting so the cross-section is not a big deal.

[John Hill]

Hmmmm, yes I can see that would give your cause to pause!

But you can make some size of wooden pully on that lathe?  Cut the big pulley near to size with you jig saw and mount it on the shaft (which you have to do anyway for your hacksaw) with the smaller pulley you have justmade so that your motor can twirl it around and with a bit of angle iron held by a 'G' clamp as your tool rest you have all you need to turn that wooden pulley.

[websterz]

Hmmmm, yes I can see that would give your cause to pause!

But you can make some size of wooden pully on that lathe?  Cut the big pulley near to size with you jig saw and mount it on the shaft (which you have to do anyway for your hacksaw) with the smaller pulley you have justmade so that your motor can twirl it around and with a bit of angle iron held by a 'G' clamp as your tool rest you have all you need to turn that wooden pulley.

Why didn't I think of that?  Actually I COULD cut a 12" pulley on my mill. Just need to bodge up a form tool from drill rod, mount the plate on my rotab, and go from there. Bike wheels will get the saw going, I can make proper pulleys later. 

[sbwhart]

Making the pulley on a mill us perfectly doable you can use the RT or another way I've seen used is fix a face plate on the mill spindle with the material bolted to it and with the cutting tool on the table:- go to it, sorry but I can't show you any pics only seen the set up in books and ME magazine.

Have fun

Stew

[Bearcar1]

OR..... make up a 'foundation plate' from a section of plywood bolted to the mill table. One end of the plate would rest under the mill spindle so that the endmill cutter could be plunged into it to a shallow depth. Outboard of the cutter on the X axis you would have devised a locating peg that would serve as a central axle for the previously rough sawn wheel blank. The blank would then be placed on the peg in the board and could be rotated on the peg. Using the table feed, the blank would be advanced into the cutter after completing one complete rotation until the desired diameter is achieved. A make shift router table in essence. Good luck with your wheels. (I'd spare the little one's bike so she could enjoy it)


Bearcar1
Jim

[websterz]

(I'd spare the little one's bike so she could enjoy it)


Bearcar1
Jim

I would not deprive my daughter of her bike...what kind of insensitive jerk do you take me for? 

The bike in question hasn't been ridden in a couple of years, since she outgrew it and got a new one. sheesh...You guys are harsh!

Now grandpa's prosthetic leg...he only uses it a few times a month...and I do need more parts to build the saw...

[Darren]

Get some nice titanium in those.....

[websterz]

Get some nice titanium in those.....

Damn skippy homes...gonna' go jack me a gam!

[jwsvandr]

Here is a circle cutting jig for use with a router. I have made the same out of 1/4in plywood and it works a treat.

http://www.stevemeadedesigns.com/board/index.php?showtopic=15852

[Gerhard Olivier]

Webster Oldder washing machines have 12" ali pulleys for flat belt to drive the drum.  They are usually three spoke tipe and the scrappy should be a lot of them.

Gerhard

[websterz]

I located a pair of 12" cast aluminum pulleys off of swamp coolers that will work just perfectly.