Machining Cross Drilled Barrel Port

[m1chaelw]

Evening

Been thinking about machining up a blank and wondered if anyone had any tips / tricks for machining the barrel port.

I'm planning to use an undersize drill suitable for cross holes then open out , but it got me thinking about how to minimise the burr / how to debur ?
Got a couple of ideas on how to do this but thought I'd ask.

Any tricks that won't risk damage to the lands.

Cheers
Mike

[Ca_Varminter]

Well for me...
I don't use a drill bit..
I use a sharp EndMill....
This will minimize burrs...
Take your time, Not a lot of down force needed..
Also Peck drill it... Drop the cutter down a small amount and back out...clear the chips

Then for the final check,
I also use a tapered diamond burr in a pin-vise.
To clean up the edges....


Good Luck,
Stuart