Tag Archives: Drilling 15-5 PH with HSS drills

Drilling 15-5 PH with HSS drills

Hi All:
We’re building a set of dies for carbon fiber molding and the dies are 15-5 PH.
The blocks are solution annealed (or so the steel supplier claims).
Keith is doing the preliminary machining and there is drilling involved.

Well, it sounds like shit!!! Godawful graunching noises; almost like drilling Inconel
Keith’s running conservative settings 40SFM, 0.002″ chipload, 0.050″ peck increment.
This is with HSS drills because the number of parts doesn’t really justify buying a bunch of carbide drills
Hole sizes range from 1/4″ to about 1″ diameter.

He’s tried a bunch of different speeds and feeds, and he’s getting through the job just fine, but Oh My God…the noise!!

You’d swear the drill is toast, but when it’s inspected, it looks fine.

Seems to be a lot of hardness variation in the blocks too; it’ll run nice and quiet till it’s in an inch and then the music starts, and then it suddenly stops again.
The chips look good regardless of whether the drill is whispering or howling.

Have any of you run this material before?
Is this about what you’d expect or do we have crap material?

BTW, Keith claims it mills just fine.

Any comments will be appreciated, (so long as you don’t demand we switch to carbide for this job).