[TheForge] Another pulley question (brazing cracks)

[Mike Spencer]

Ralph and others with cast iron brazing experience:

What do you think of brazing two spokes cracked near the hub in a
2-sheave cast iron pulley?

It's ca. 16" diameter, takes two B belts.  I would use it 900 RPM on a
2" shaft, 15-20 HP and a fair amount of starting torque but no impact
loads while running.

I have refractory brick and ceramic blanket so I could build a box and
pre-heat it pretty good with propane, then braze it.  Any other
precautions?  Bad idea altogether?  Grind a deep V?  Cool slowly? Very
slowly? 

I've brazed up some cast stuff before but never a spoked wheel and
never for a dynamic load.  Suggestions or tips welcome.


Background if yr interested: 

I have a 20 HP Wisconsin air-cooled, 2400 RPM industrial engine.  Have
in mind connecting it to a small jackshaft with a flexible coupling
(or maybe U-joints). A 6" pulley on the jackshaft would drive the 16"
pulley on a heavier shaft which in turn would drive the 24" gear on my
A&O 300# hammer.


- Mike

-- 
Michael Spencer                  Nova Scotia, Canada       .~. 
                                                           /V\ 
mspencer at tallships.ca                                     /( )\
http://home.tallships.ca/mspencer/                        ^^-^^

--