Brake Drum Flange Thickness

G

GBewley

Well Known and Active Forum User
VOC Member
I am attempting to build some of the wheels I have been collecting for some of my bikes. I was talking to a member in the UK this AM and he suggested I measure the thickness of the mounting flange of the brake drums (specifically Shadow ones) which I am hoping to use. This is the flange through which the bolts go to join the drum, spoke flange, and hub together. Having measured them, I find that most are in the 0.195-0.200" range, but one is up to 0.212 (no paint on this one either, as opposed to the others) and one, with paint, is down to 0.188". So the question is does anyone know what the original thickness here was to be? My friend suggested that some re-pops made back in the day were thick enough so as to cause the hollow axle to end up inboard of the brake plate enough so as to not be usable. If needed, I can turn the drums, but a figure would be nice.

Thanks,

Glenn
 
C

chankly bore

Well Known and Active Forum User
Non-VOC Member
Hi, Glenn. The original cast iron ones I have measured are all around .200" Maybe the earlier steel ones were thinner but I'm only guessing. Did you get the photograph I sent? Cheers, Charlie.
 
K

Kansas Bad Man

Well Known and Active Forum User
Non-VOC Member
Your low and high figures are a .024 difference. machined cast iron surfaces are often a plus or minus .o10 . If you are to consider the hub spools flange to flange distance which also varies, and then the spoke flange thickness vary as well. If it were me I would measure all the parts that determines the final over all length of the assembly , swap the parts around to make the amount of assemblies you have as equal as possible in there length , why make swarfs and in the case of cast iron dust out of a Vincent part when not necessary?

Regards Max
 
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