How would you hold this for drilling?

[Archer60x]

I can't tell from your drawing, but are the two holes in the bottom of the block tapped ? If so, why not use those two holes to bolt the part to an angle plate, clamp the angle plate to the mill table and then perform the needed operations.

Ted

THey are... i have been so focused on these big through hole i did not think to make those first to use for clamping.

 

[Flyinfool]

What is shown in the pic will work. BUT if the hole on the bottom goes through you will want a sacrificial pad under the part so that you do not drill into the vice jaw.

 

[Archer60x]

What is shown in the pic will work. BUT if the hole on the bottom goes through you will want a sacrificial pad under the part so that you do not drill into the vice jaw.

Roger that! it would be like me to poke a new hole in my vise. Did it to my drill press table.

 

[Archer60x]

Now hopefully i dont run out of Z.

 

[Archer60x]

Reamer is too long... can i cut it shorter? or am i committing a sin on this used .503 reamer i got on ebay?

 

[Flyinfool]

Open the vise farther and set the part into the vice with that sacrificial pad and clamp the vice onto both the part and the 246 block and then add the clamp at the top if needed. That will buy you another inch or so of "Z".

 

[mmcmdl]

Use a solid square to position the part . Looks as though you just sat the part on the small edge . If that edge is out a little , it will be multiplied by 4 times or so . Maybe not important .

 

[pontiac428]

Put the reamer in a collet for more Z and less runout. Drill chucks are not ideal for a finishing step like that.

 

[Janderso]

Something like this looks better. Need another strap clamp on other side. Left it off for better visibility.

View attachment 477687

Put a sacrificial block on your vice jaw otherwise.......

 

[Just for fun]

Good question, and lots of good ideas.
Following along to see how it goes.