Ok to make pulleys?

[mike_starling]

Guys,

It just dawned on me ... dummy that I am ... that I have the stuff to make the flat surface pulleys that I might need. Material is cheap on eBay. My shop has a mill with a good DRO, and a big lathe. I made the entire set of fittings for the sway bars, so I'm not a complete klutz with tools.

Can I not make the flat surface pulleys from 7075 T 651 aluminum plate? Is there any need for heat treat afterwards?

thanks,

 

You should not need a heat treat if it's turned from 7075 plate. 7075 is very expensive, so unless you can borrow a piece, I would probably choose steel, but it would increase your machining time and weigh more.

Look in to hard anodizing. It works great on some aluminum alloys, but I don't know about 7075.

 

[Steve Toner]

Hey, you want fiendishly expensive, look into titanium plate /ubbthreads/images/graemlins/shocked.gif

I would think 6061 aluminum would make fine pulleys. It's not really all that cheap - $67 for a 12"x12"x.5" plate at Online Metals (but an equivalent titanium plate is $292.50)...

 

Come on, Titanium is heavier than Aluminum, but Berrilium...

 

[Trevor Booth]

Mike, the T651 designates that the material is already heat treated (T0 = annealed) Depending on the final shape of your pulley, you could use 5083 H32, 5086 H32, 6061 T5 0r T6 plate.
If you use a piece of an extrusion billet it will be in the annealed condition and it is preferred to heat treat. You may need to heat treat before machining as thin sections may exhibit some distortion.
Cheers

 

[Steve Toner]

Alternatively, you can get aluminum round bar and slice off the thickness you need. The same place I linked to above has 6061 (T6) extruded round bar in diameters up to 8 inches

 

[Steve Toner]

Not a pulley, but here's a before & after shot of a spacer made from a slice of 4.5 inch round rod. This is actually a little larger than the biggest practical size that my mini-lathe can handle, but where there's a will there's a way... /ubbthreads/images/graemlins/smile.gif

 

[Steve Toner]

Oh yeah, and check out McMaster-Carr for somenice aluminum discs in various diameters and thicknesses that might make good pulley stock.

Select Metals under Raw Materials and Springs, then Aluminum, then Discs.

 

[Chris Duncan]

Most of the aftermarket aluminum pulleys are 6061 T6. I haven't got to this point yet but I'm going to machine my own because of close clearance issues.

I would measure an existing aluminum pulley for thickness and diameters so you don't have to re-invent the wheel(pulley).

 

[Gary Gibbs]

You can get a custom made aluminium pulley for about $95. Just send them a CAD drawing. This is what I did for my water pump.