Hi all
A friend & I both need sprockets machined off & replaced on rigid b31 hubs
Not having much success in finding someone who can do this so far - a lead I had on some old boy has resulted in no progress & no reply
Any leads on who can do are welcome
Br
Jo’b
There's a potential problem with this as the sprocket teeth are very close to the brake drum and the drum is fairly thin...So, a degree of care must be taken when welding on a new sprocket ring if penetration through to the braking surface is to be avoided...
Someone with a Tig welder who knows how to drive it is a must for this job...When I did my rigid B33 many moons ago I just 'stitch' welded the sprocket onto the drum...In other words intermittent welds around the sprocket on one side and the same on the other side but not in line with the previous welds but with the gaps between them...
Ultimately I replaced the entire hub with a later 'crinkle hub' type which has a separate brake drum/sprocket that is still available to buy (unlike the earlier type)....Not much help if you want a standard bike though...I believe 'Supersprox' will make custom steel sprocket blanks to dimensions supplied...Ian
If it's a loose hub it's much easier. Sprocket blanks are easy. Most bearing retailers carry them. We make aluminium rear sprockets and as such have a reasonable stock of big ones. Not a lot of use to you.
No point in buying a quality sprocket blank as the welding will change it's temper. If you can't find anyone near to you John I can do it.
Mark...Do you know anyone that can produce from a pattern a 46T, 5/8" x 3/8" aluminium sprocket for me?...I've been trying to get one manufactured without success so far for my latest project...Ian