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Old 11-24-2015, 10:52 PM
Jim.Thompson's Avatar
Join Date: Sep 2015
Location: Bellingen NSW Australia
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Originally Posted by w8ye View Post
Don't forget to have a radius to the inside corners or you will create stress points
The only corner that could apply to is the end of the 25 mm counterbore and that is already done. It has to accommodate a washer anyway, so don't know how I could have done it and still have a washer seat properly?

I've successfully mounted the hub on the mandrel and machined the taper for the crankshaft. All looks good, I had a small amount of difficulty getting it off, but it's ok. Just took heat and a puller with some small amount of torque on the spanner to get it moving.
In my eagerness, did forget to cut the key slot, but can chuck it up again and cut that tomorrow.
I plan to machine up the drilling guide to a 34 mm hole circle and 5mm bolts. Some stock is in the chuck of the lathe already and partially machined down to size. I will machine a spigot on one end to fit into the 25.025mm counterbore of the prop hub and a 10 mm hole through it to take a centreing bolt to drill the prop.
An alternative idea is to machine a 10 mm spigot on the other end to fit the prop instead of a 10 mm bolt hole. This might be the better way.
After it is made, I'll use a drill press to drill the 6 holes for the 5 mm machine screws in the prop hub. Drill one, cut the thread and screw in the bolt, then drill the rest of them.

Last edited by Jim.Thompson; 11-24-2015 at 10:57 PM.