- Joined
- Mar 22, 2013
- Messages
- 215
The next operation was to drill all the oil holes from the throws to the main journals. These are .062 diameter and a standard jobbers length drill will just make it through by holding about .25o of the shank.
I set up my angle table for this operation and indicated it true both for parallel and angularity. The fixture plate was then mounted, indicated and clamped.
The crank was clamped in place and I used the same procedure for aligning the throws as I did when I machined the counterweights. I then found the center of the crank with an edge finder and picked up the scribed layout line for the hole center.
The hole were first drilled with a #2 center drill which gave me a .062 pilot hole. I then proceeded to peck drill with the drill going down about .125 at a time and pulling it out to clear the chips. No need to have something nasty happen at this point.
When I saw bits of aluminum come out of the hole I knew I was through. All in all it wasn't as bad as I thought it was going to be. I used a brand new drill just to be sure.
gbritnell
I set up my angle table for this operation and indicated it true both for parallel and angularity. The fixture plate was then mounted, indicated and clamped.
The crank was clamped in place and I used the same procedure for aligning the throws as I did when I machined the counterweights. I then found the center of the crank with an edge finder and picked up the scribed layout line for the hole center.
The hole were first drilled with a #2 center drill which gave me a .062 pilot hole. I then proceeded to peck drill with the drill going down about .125 at a time and pulling it out to clear the chips. No need to have something nasty happen at this point.
When I saw bits of aluminum come out of the hole I knew I was through. All in all it wasn't as bad as I thought it was going to be. I used a brand new drill just to be sure.
gbritnell