Thought I would show you a behind the scenes video of how we machine a inside chamfer on the Rollmaster and JP brand double roller timing chain's crank gears using a manual lathe.
With out this chamfer, you run the risk of wearing your chain wrong, quickly, and possible failure of the chain, which can also turn into a total engine failure. (also makes it to where the crank gear actually makes it onto the crank all the way, and mates up will with the slight chamfer the crank has - which saves your crank gear from braking in half) *Happened to Reptile*
Along with this set up, we also SURFACE GRIND the oil pump cover, removing 0.020" off the inside to give you even more clearance between the chain, and the cover to account for "crank walk:" and crank end play.
I will do a video showing how we do the oil pump covers another time in another video.
Set up picture with a dial indicator so we know its perfectly centered in the jaws of the chuck:
The video of the process:
YouTube - Crank Gear Machining
By using a manual machine you can hold a much tighter tolerance than with a programed machine, also, its a hell of a lot cheaper on set up and over all machine costs. Using the caliper, holds true that each one is machined damn near perfect.
If I were doing many hundreds of these, then yes, might look into actually programming a machine, but for one and two every now and then, this works very nicely.
Final picture of the two different kinds finished.
(as pictured left to right: stock, Rollmaster double roller, JP double roller)
Only costs $25.00 each to machine, includes set up and machine time. Took less than 25 minutes to set up, machine two of them.
So there is your latest on a GR8racingfool behind the scenes video and picture post. ;D
~F~
