Search:

Sure, I'll get into this further and post back.

Hi Chris, thank you for the reply.
I'll test what you've suggested.

Not sure if just got lucky because I've been making these drill holes for a slip fit with a 6mm pin. Actually for pins I'm...

Sorry, forgot to mention that I'm using spot drill always.

The material is S235JR (calibrated steel sheet), Feeds and speeds (for the drilling operation): 760 RPM, surface speed 14.3 m/min, plunge feed rate 20 mm/min, pecking depth 1.5mm.
I've also tried...

Hi Chris,
I've tried after that drilling on the same aluminum material that I have perfect holes with the same speeds and feeds but couldn't repeat that result.

Red layer in the middle of the holder? Sorry don't understand what do you mean by that.
EDIT: I see now, interesting build.

Thank you for the reply.
I do understand that, it was accurate enough for my purpose and now the holes are way oversized.
I've also tried to drill with 5.7mm and then use 6mm reamer. That didn't...

Hello everyone,

Some months ago I've been drilling pin holes (6mm) with very tight accuracy.
The pins were just sliding into the holes smoothly.

But on the last job I've lost that tight size...