1/3 scale Chevy

[sandcrab]

This is the first CNC operation on a 1/3 scale Chevy smallblock. I started the patterns in 1997 and made the master a double shrink so that someday I could cast the block in aluminum as opposed to the cast iron that is in my avatar. The original was machined on a manual Bridgeport, but since then I have added the Series I CNC running Mach3 and have started to learn a new skill.

The grid plates were done in another thread, but I added the fixture so I could clamp the bearing cap casting in it and run a G55 offset to surface and then drill the bolt holes. The last operation will be sawing the caps apart and mounting to the block for line boring.

There are no drawings for these parts, the patterns were carved in wood from reduced tracings, so I used the wizards and learn programs to write the code. There are bosses for locator dowels on the block, so when I get to the firedecks and pan rail I hope to be able to just use Motor Manual numbers divided by 3.

[Chaoticone]

Very neat!  Thanks for shareing.

Keep us posted,
Brett

[RICH]

Keep up the good work and keep posting pic's.
RICH

[sandcrab]

Thanks, will do. Holes in caps today, then layout block for the recess.

[sandcrab]

I mounted the block in a fixture on the gridplates and started to compile the code for the bolt holes. I saved once in the wrong file, and overwrote the cap casting hole program so will have to reserect those measurements to finish the recess and holes.
Here is the cap casting drilled and ready to be separated on the block.