Scratchbuilding pulleys?

Anyone like to share their idea's or methods for making engine pulley's? Doesn't matter if styrene or aluminum, just looking for different ways for a project I'm working on. Thanks! ~ Mike

Well, I modify them with masking tape, painted black.

It's a method based on this tutorial :evillol:

http://www.italianhorses.net/Tutorials/Drivebelt/dbelts.htm

I was talking more about the pulley's themselves, not the belt. But nice tut. in that link anyways.

Anyone?

Check with Scale Auto magazine or Ebay for the "Car Modeler 2001" magazine. This is/was an annual publication that featured the machine work of Augie Hiscano. He deals in detail with how to machine pulleys. This is a must have magazine for those wanting to machine their own parts.

If you don't have machine tools handy you could try resin casting a set from a good kit.

I have layered styrene with a mount for a dremel and used an xacto blade to make true and accurate round parts. Since I have no machine shop or lathe it was all I could do. Simple cutting can provide great results and detail. BUt this is me, and I am sure there are better options.

If you have access to a Waldron hole punch, something like that would work great for making pulleys from sheet styrene. Just sandwich together different diameter pieces, and voila, one pulley.

thanks for the tips. I'm experimenting now using thin slices of aluminum tubing I cut with a mini miter saw. I think I will try using styrene chucked in the dremel also. I will post the results. I wish I had a lathe, but not really in the budget right now.

If you have access to a Waldron hole punch, something like that would work great for making pulleys from sheet styrene. Just sandwich together different diameter pieces, and voila, one pulley.


Yeah, but how many people do you know actually have one of these mythical contraptions? :eek7: :grinno:

Here's another idea I used in my pre-lathe days:

Get several diameters of brass tubing. Cut a 3ish inch length of each, and sharpen one end of each (use a file or the like to 'cone' one cut end). Place the sharpened end on a piece of sheet styrene on a sturdy wooden surface, and hit the other end of the tubing several times with a mallet. There- a low rent set of punches that will cut small discs of styrene. Sandwich these discs together to make pulleys.

Obviously you'll need to resharpen the cutting edge often (brass is pretty soft and the edge isn't very durable), but it will do the trick. :2cents:

Thanks MPWR for the tip. I was looking at the punches that Micromark sells but their $40.00. I may go to hobbylobby at lunch to see about those mythical hole punches also!

I did have some luck with layering thin slices of aluminum tubing, looks nearly like a machined piece. Adding some PE pulley faces and they look outstanding. I'll try to get some pics up later tonight. A lathe is looking more and more attractive...

AFAIK you wont find the hole punches at HL. Ive never seen one there. If I had, I'd probalby have jumped on it pretty fast.

And I actually know quite a few people who have the Waldron punches, but most of them are into aircraft & armor modeling, where their use is more common.

Hobbylobby did have the hole punch, I seen it there before. Picked it up at lunch. Not sure what the punch your talking about looks like, but this one has a wheel on it with various sizes of holes you can punch out. It was 7.00. Says right on the package you can use it for plastic, etc. I'm going to give it a go later tonight.

And I actually know quite a few people who have the Waldron punches, but most of them are into aircraft & armor modeling, where their use is more common.

http://images.kitlink.com/Products/images/Waldron/wr0018.JPG

Turns out I have one also. ;) It's a very nice tool, but it's rather expensive and not the most obvious or necessary modeling tool on my workbench. They've gotten more expensive since I got mine, and a good bit harder to find- rumor has it that they're no longer being made. You might be able to get one here (http://www.greatmodels.com/~smartcart/cgi/display.cgi?item_num=WR0018). It would be perfectly good for making pulleys, provided that you don't need one as large as 4" in 1/24.

Yea, they arent the cheapest tool in the world, but I woudlnt mind having one evnetually.

Im concidering making one in the machining classes that Im taking at the local comm. college.

I was looking at a similar punch set from Miro-Mark

MICRO PUNCH SET
Item Number: 83513

$40 is a bit much but less than the other.

sorry mates, fell asleep last night ... ha ha ha

I will post pics later. The rotary punch tool I got from HL works very good actually. I may pick up the punch from MicroMark though because it offers larger sizes than the rotary tool.

Thanks, I'd love to see a picture of what that thing looks like. I may have to get one for myself.

MPWR, can you take pictures of the punches? Im specifically interested in the punching end. Want to know how the end is beveled to great the cut out.

There's nothing at all fancy about the cutting ends of the punches. It's simply a very clean, sharp 90deg edge.

I think that you may find a punch and die set a bit harder to make than you expect. Both the punches and the die need to be made of hard steel. I'd recommend drill rod for the punches (air hardening if possible), and I'm not sure what I'd use for the die. Also, I suspect that to get good cutting edges on the die, the holes need to be reamed, not just drilled. This is likely why they're so expensive to purchase.

I've tried it, and met with rather limited success. Limited enough that purchasing a set seemed reasonable. Really, it's the kind of machining that I don't particularly enjoy- simple operations on difficult to machine material, as opposed to complicated operations on easy to machine material.

Yea, I could see having to ream the holes for added accuracy.

It was just a thought for an interesting project. Ive got access to several CNC machines in my machining class, so I dont think the machining aspect would be all that difficult.

Dunno if I would do it or not, just something I was thinking of doing, thats all.

Ive also concidered making my own photoetch bending tool, similar to the hold-n-fold & the etchmate. Again, just for a project in class, and to see if I could do it.

Hi guys, got home late so not many pics but I have some ...

Here is the punch from HL-
http://i53.photobucket.com/albums/g47/shucky4ya/Karmann%20Ghia/IMG_1528.jpg

Styrene holes fresh out of the punch. Very little sanding is really all thats necessary, I think they came out better than expected.
http://i53.photobucket.com/albums/g47/shucky4ya/Karmann%20Ghia/IMG_1529.jpg

The aluminum tubing slices cut with power mini miter saw. These look great too. I'm going to use these on my project. Going to cut the "inner" smaller tubing to size, space the sliced tubing "rings" and epoxy in place. The front of the "pulley" will then wear a Mr. Model PE pulley face. When they are done I will post a pic also ...
http://i53.photobucket.com/albums/g47/shucky4ya/Karmann%20Ghia/IMG_1530.jpg
http://i53.photobucket.com/albums/g47/shucky4ya/Karmann%20Ghia/IMG_1533.jpg

I have had very good results chucking the larger sprue sections in a drill and using files and sandpaper, making the pulleys with that. You can make them in whatever shape you need, then just cut em off and make more. Then, using a few layers of chartpack tape for the belts. I even made the dome style pulleys like on the water pump or flathead motors. Good luck!