The little glitch…. potmetal.

By: frugalhorn

Apr 16 2013

Category: Uncategorized

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When heat was applied, in an attempt to braze the parts of the stop arm, it quickly became apparent that this is not going to work. The Yamaha stop arm has been cast out of pot metal, which will not take the heat to braze, 0r even solder for that matter…321 new reversal-16so another tact must be taken…We’ll modify a valve and a brass stop arm to be adjustable to set up the proper alignment of the change valve.321 new-2 reversal-1The   brass stop arm has a smaller mortise than the Yamaha. I’ll modify the lower bearing to make it small enough to work within the brass stop arm. If I enlarged the mortise on the brass stop arm, it would weaken it. When the cuts on the lathe are done it allows the stop arm to rotate around the bearing shaft. so that the correct alignment of the valve ports can be reversal #3-1once the alignment is set the bearing shaft and stop arm are notched to indicate proper alignment. the stop arm is locked in place with the back bearing screw….

new reversal #3-12After this work was done It became apparent that using another mortise cut Yamaha stop arm will work for this reversed change valve. Duh, maybe I should have tried the ones I had lying around before all the other work, well,  As usual I’ve learned something….More to follow.


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