4142 Pre-hard?

[Highpower]

Question for the metallurgists in the house.

Is it possible to machine, drill, tap with HSS?
(Rockwell C28-C32)

[TomG]

(08-17-2012, 09:22 PM)Highpower Wrote: Question for the metallurgists in the house.

Is it possible to machine, drill, tap with HSS?
(Rockwell C28-C32)

Absolutely Willie, just run it about half the speed of mild steel.

4142 pre-hard is what I'm using for the barrel on my Steven's Favorite.

Tom

[Highpower]

Ok, great. Thanks Tom.

Actually - I better double check my tap set (Brownells) to make sure they aren't carbon taps. I need a couple of 8-40 holes and I really don't feel like breaking any more cutters this week.

..... weld beads.

[TomG]

(08-17-2012, 10:40 PM)Highpower Wrote: Ok, great. Thanks Tom.

Actually - I better double check my tap set (Brownells) to make sure they aren't carbon taps. I need a couple of 8-40 holes and I really don't feel like breaking any more cutters this week.

..... weld beads.

Hey Willie,

If you have any of the old (pre-green) Tap Magic, that would be helpful with tapping the stuff.

Tom

[Highpower]

No - I've got the sissified Tap Magic with "EP X-tra".

But I do have some Tapmatic "Dual Action #1" that has some trichlor in it. Or some Moly-Dee...

Oh, and the Brownells taps are carbon steel.

[PixMan]

Aside from the drilling and tapping, what other type of machining operations need to be done?

I'd also use HSS drills and taps, but for milling and turning that stuff is what carbide tooling simply loves to cut.

[Highpower]

Ken, I only need to mill some flat stock to reduce the width. I have a handfull of carbide end mills so that isn't a problem. My main concern is in threading a couple of holes. The only 8-40 tap I have at the moment is carbon steel.

The stock is only 3/32" thick, but with my luck.....

[Sunset Machine]

You know you can touch taps up on a stone, even a bench grinder, right? Just hit the end on the inside a few licks. Inside the flute, the "top" of the cutting face. Look at a gun tap. You can easily feel the difference, before and after. Drill your hole for 50%, should be fine but work carefully. That's miserable stuff.

[Highpower]

Well I guess I'll cut off a test piece first and see what happens. I don't know that I could get away with 50% since these screws are going to get some pounding from recoil. (Scope mount.) I need all the thread purchase I can get in only 3/32".....

Me? Hand sharpen a tap on a bench grinder??? Boy oh boy, if that isn't a disaster waiting to happen!

[DaveH]

(08-18-2012, 09:19 AM)Highpower Wrote: Me? Hand sharpen a tap on a bench grinder??? Boy oh boy, if that isn't a disaster waiting to happen!

Willie,
You could hold the tap in a vice and use a 'Dremel' - now that I know you can do

DaveH