drilling 304 stainless
drilling 304 stainless
(OP)
I am drilling a 1" Hole (#30 drill bit) through 304 SS. My problem is bit breakage. My parts, which are being hand drilled, is part of the problem.
I would like to know the best style/hardness of drill bit and lubricants to use. Also there has been some debate in my machine shop about the angle of the head of the bit, we are using a 118 degree bit.
Any help would be greatly appreciated.
I would like to know the best style/hardness of drill bit and lubricants to use. Also there has been some debate in my machine shop about the angle of the head of the bit, we are using a 118 degree bit.
Any help would be greatly appreciated.





RE: drilling 304 stainless
thread281-128899: 17-4 stainless
Regarding lubrication, use a flood of lubricant specific for stainless steels. This means it has been compounded with sulfur-containing EP additives. Castrol Ilocut 5468 is one example:
ht
RE: drilling 304 stainless
Drill rpm shouldnt be above 570 for 1" hole. What type of lubricant are you using now?
RE: drilling 304 stainless
RE: drilling 304 stainless
RE: drilling 304 stainless
RE: drilling 304 stainless
RE: drilling 304 stainless
Regardless, you're breaking them by running them too slowly.
Double the speed, at least.
Mike Halloran
Pembroke Pines, FL, USA
RE: drilling 304 stainless
RE: drilling 304 stainless
Nick
I love materials science!
RE: drilling 304 stainless
It is a .1285" DIA. drill bit.
Could the angle of the bit also be the problem? I'm using a 118 degree bit.
RE: drilling 304 stainless
RE: drilling 304 stainless
We routinely drill 3.2 mm holes in SS with L/D's up to 12 with very few problems. We use both single and multi spindle drill presses.
The drill bits we use are from Guhring with the following description from a packet of 10.
Art. No 658 K
DIN 338 RH
S-Bohrer GT1
3.20 mm
HSCO EDBB
1272/7
All of our precision drilling is accomplished using Guhring drill bits. We are able to have Guhring resharpen each bit 3 times without any loss of performance.