Cain

iTrader: (291)

Looking for some countersink bits for metric, probably buy from amazon anything in particular to watch for? Drilling into 1/10 metal chassis.

Silverbullet555

iTrader: (13)

Just get the right angle.

belewis01

iTrader: (4)

Metric is 90 degree, SAE is 82 degrees

Cain

iTrader: (291)

thanks, looks like a variety all have the same "look" so orderd up a set to give a go. will report back.

LowClassCC

iTrader: (9)

also some older SAE is 100 degrees

billdelong

iTrader: (33)

I've had really good luck with Perma Grit:

https://www.permagrit.com/fc14/


I drilled holes in a chassis to move the battery tray forward on my Hyper10TT back in the day to get more rotation on turf:

DARKWAV

Hmmm, didn't know that. Makes me wonder what kind of bit I have been using all this time. I'm going to have to take a closer look at it now.

ta_man

iTrader: (167)

They aren't cheap but what I use are three flute aircraft aluminum countersinks or carbide countersinks. I have one each of the aircraft ones for SAE and Metric. I use the carbide tools for carbon fiber and also for plastics where the 3-flute seems to not give as smooth a cut as it does on aluminum.

Quite honestly, the only way to get a good countersunk hole is to have the workpiece clamped down firmly and a limit stop on the tool held in a drill press or a milling machine. Doing it with a countersink cutter in a hand held too always results in bit chatter. A grinding bit won't chatter but also will not give a good finish and is unlikely to give a proper profile cut.

Rick Vessell

iTrader: (10)

Get one each of 82, 90, and 110. Then you will have every screw you come across covered. The larger, 8/32 screws, etc. use 110'.