[SEL] OT gear making in brief

[Judge Tommy Turner]

Rich,

    I agree with what you say!.....  I have an undergraduate degree in 
engineering and its been a long time since I've seen some of the info 
you discuss.  You do a great job in your explaination.  In the 1970's I 
attended the Bluegrass Steam and Gas Engine Show in Harrodsburg, KY.  I 
had the pleasure of meeting a gentleman who had worked at the Hagan 
Engine Factory.  While he had several years on him, his mind was sharp 
and the hour or so discussion I had with him revealed a wealth of info.  
I remember him telling me about some of the things they did, or the 
"tricks" they pulled before an engine was let out of the factory.  One 
had to do with the cam gears.  Many of the Hagan engines had the cam 
shaft mounted in a off center housing. In order to adjust the cam 
movement (to give it more or less thrust against the cam rollers), the 
housing was twisted.  When this occured it would set the gear off center 
and would cause the teeth to mesh at an angle to one another.  He told 
me that once they got the engine timing, valves, etc. all set at the 
right spot, there would sometimes be gear noise do to the offset mesh.  
They had a simply solution.  They lapped them in.  He said they had a 
mixture of grit and grease that they would allow to go through the gears 
and after a bit (depending on the degree of the offset) the noise would 
lessen and the engine was ready to ship.  Actually they were just 
wearing the teeth in mesh with one another.  I used this once as I had a 
4 HP Famous that had 4 teeth missing from the cam gear.  I built them up 
with brass, did what I thought was a good job of machining them back on 
and then put the gear back on the engine.  Every time it would get to 
the point where the new teeth were I would hear "rump, rump, rump".  I 
got some valve lapping compound and after about 30 minutes of gradually 
applying a couple of tubes through the gears, the noise greatly 
subsided.  Since the brass was a lot softer than the iron gears, most of 
the wear was "lapping" the brass teeth to match the others.  I ran  the 
engine at shows for a couple of years and never had any problems. 

Tommy Turner
Magnolia, KY