making multi-vee pulleys?

>

I made a 2.5 -1 triple pulley set on my 6 inch atlas lathe. I just turned the od of bothe the driven and the driver out of aluminum, figured the angles that I needed to plunge a very thin tool and went at it. They lined up fine and I used them on a gokart.

I'll try and do that. What I am doing is a 400mm flat lap for glass. The basic bearing assembly is from a VW polo with drum brakes, neat assembly with bolt on stub axle and integral drum hub, not uncommon. The Poly V belt was chosen as I could get the approx 6:1 reduction in one stage and due to the poly V allowing down to 20mm driving pulley it would fit in the desired space unlike a V pulley which would have to be much larger. In my case the driving pulley will be about 35mm with a

50hz 1425 RPM motor. The other th> Thanks David - useful info and more comprehensive than what I had.

As I thought - not too difficult.

Thanks Jordan

daniel peterman wrote:

Cool. I will be making a 3 inch crankshaft pulley for the race car on monday, seems simple enough. I would like to make a serpentine setup for the rock crawler i am building at home. Anyone have specs with the small V angles and spacings? My Machinery's Handbbok is pretty old.

I don't think the newer MH have it either.

Dig around online for Poly-V belts.

This stolen directly from an earlier post in the thread, by Mr David Billington.

Cheers Trevor Jones

Inclusive angle of the V is 40 degrees. Don't know the pitch though. Just measure a pulley or belt.

Graham Horne

I can donate free cog belts. (not very big)

i

I can donate 3000 of them. In all sizes.

I gave away 20 double sided timeing belts, 2 and 4" wide to a robots group in a college in So Cal not long ago.

Gunner

Rule #35 "That which does not kill you, has made a huge tactical error"

Apart from the Contitech data which I have worked through and is quite straightforward and comprehensive I also found the following from Gates

This is software you can register for and download, I haven't tried it so can't comment >Cool. I will be making a 3 inch crankshaft pulley for the race car on

cool, I can donate 10, looking to get rid of them.

i

Perfect! Thanks

Had a look at it - doesn't have info on making pulleys, but easy to use for helping choose sizes, speeds, loads, etc. Also gives belt tensioning info and some other data. Nice printout function. Jordan

Thanks Jordan,

I may download it a have a look. The only bit I didn't quite get with the Contitech info was to do with the belt tensioning, all other parameters seemed straightforward.

Cheers

Dave

Jordan wrote:

Some more info here:

The SIT brochure has depth of groove info, which the Conti doesn't.

Now I'm looking at making the tool.

40 degrees should be easy enough. No top rake on the tool will help get the angle right. I can probably get the bottom radius in the correct size range, but the top radius is a challenge! For the "J" size I'm making the dimensions are quite small. I don't see me successfully grinding this detail into the tool, so it'll be dealt with by careful filing smooth after cutting the V's. Fingers crossed.

Jordan

Thats the way I was going to go. I ground the single point tool in the usual manner to 40 degrees and added the tip radius with a stone by hand. I haven't done it yet but was planning to cut the grooves then add the top radius after with a small file as you are. Spent some of yesterday welding up the frame for the lap project so when I do the pulley I can assemble the whole thing showing the complete application.

If you still need info after Tuesday I'll see if I can find it at work...