pic: Custom Machined Aluminum #25 Sprocket

Custom machined #25 40 tooth aluminum sprocket. One piece construction and tapped bolt holes eliminate the need for spacers, nuts and allows for shorter bolts.

Looks nice… These were in the drive I assume.

How long did it take to machine? How many set ups? (I’m assuming one on a CNC mill and one on a waterjet/lathe)

do you know if the amount of weight saved (how much did it save?) was worth the extra time?

Machining time was a little over an hour. 1 setup on the mill. Holes were tapped by hand afterwards. Slight tooth chamfer was done on the lathe afterwards.

Was it worth the time? Probably not, but they do look nice.

Did you cut the teeth on the mill as well?

If so, what diamater cutter was used?

Are those radiused areas in the center contoured?

Or do they just happen to be the same radius as a ball endmill you ran through there?

Those are some sick sprockets.

Woah. I don’t think I’ve seen a sprocket that sexy since one of 233’s huge pink ones… This one is just elegant though! It makes me wish more and more that my team had a CNC…

Nice job!

two words: SICK NASTY!

190 had AL drive sprockets (31 teeth, I don’t know why they HAD to be 31 teeth), but they were no where near as sexy as that beast…nicely done

Pretty snazzy!

Form does indeed follow functionality.:smiley:

What feedrate did you cut it at? That’s a lot of material to remove just to avoid using spacers. But it does look quite nice.

TyTown those sprockets are absolutely ridiculous, I want one :yikes:

as Borat would say “Very Nice”



It wouldn’t take much to cover the teeth and powder coat it for an genuine look either. Very nicely conceived, though I’m curious as to what a F.E. Analysis on it looks like. It looks at first glance as though the dips on the inner ring between the sets of holes would be the weakest points.

Probably true, but it looks to be atleast as thick as the standard sprocket thickness there. So, it is no weaker than a normal sprocket most likely.

(this is just an assumption… If I had the model, I’d run FEA on it to verify)

I don’t think the thickness is under question it is the webbing on the profile.

A beautiful piece–great job!!

I’d love to see an FEA analysis as well.

Yes, the teeth were milled. Off the top of my head, I believe these are the operations we performed. It was a couple of months ago so the feeds and speeds might not be 100% accurate.

5/8" roughing endmill 1000rpm 4"/min roughs out tooth face and bore
1/2" ball nose endmill 1200rpm 2"/min put radius’ around bolt holes
1/4" roughing endmill 1800rpm 2"/min roughs out medium sized pockets
1/4" plain endmill 2000rpm 6"/min finishes medium sized pockets and bearing bore.
1/8" plain endmill 2500rpm 1.25"/min mills small pockets, spot drills bolt holes, and outside sprocket teeth.

CAD files are available for anyone who wants them. As for FEA, if anyone wants to do it, go nuts.

Wow, those feeds seem really slow. Must have taken a while. What machine were you using?

i’d say those feeds look pretty good to me, based on the machines i have used and the total size of the sprocket

Will the sprocket be anodized, or nicely buffed? (I’d tend to prefer buffing, since aluminum really works well)