Drilling hard material

I've got some 1095/15n20 damascus steel I'm working on and while it grinds
ok, I'm having trouble drilling it. I used a cobalt drill and a carbide
center cutting end mill and neither one seems to be doing a good job.
Even after I took the end I need to drill up to a dull red heat.
Any suggestions?
Reply to
Todd Rich
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Are they dulling quickly or just not penetrating the metal? I've had decent results with a HiRoc drill.
Reply to
Jim Wilkins
Just not penetrating. However, I realized after I posted this that even though the metal gets softer when you heat it up, it doesn't revert to its pre-hard state until you get it past the critical temperature. I can drill them now, but it still kind of rough.
I'll check out the HiRoc drills. Thanks!
Reply to
Todd Rich
If this works out for your job, you could try the old gunsmith's trick, which is to chuck a nail with a rounded point in the drill press and heat the spot with friction. You don't have to get it red -- going through all the shades of blue will do it. Then you can drill it with a good HSS bit.
Of course, it depends on how thick the material is, and whether you can tolerate softened edges on the hole.
-- Ed Huntress
Reply to
Ed Huntress
I recently had to drill through some high strength steel (Proto socket extension)
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It was a pain in the ass and a regular drill bit was unable to drill it.
I had to use a carbide end-cutting endmill.
Reply to
Ignoramus699
done this will cheap bed frames, protype, etc...
use propane blow torch, just red up the hole for drilling
bed frames...good for pratice, welding
xman
Reply to
xman
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Have a look at the Twisters if you have difficult drilling applications. They are specifically designed for tough materials.
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Reply to
John R. Carroll
Buy some solid carbide drills. They work just fine red hot. Drill small holes and then work up - easier to work it that way.
Martin Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net TSRA, Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal. NRA Second Amendment Task Force Charter Founder IHMSA and NRA Metallic Silhouette maker & member.
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Todd Rich wrote:
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Reply to
Martin H. Eastburn
I once drilled a 3/8" hole in the end of a large tap with a carbide drill in my lathe. It was very hard but the carbide worked wonders, it was a 1-flute straight drill.
Free men own guns - www(dot)geocities(dot)com/CapitolHill/5357/
Reply to
nick hull
But if I've already taken it up to red hot, and it still won't drill, I don't think this is going to help much.
Oh, and this is how they turned out:
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Reply to
Todd Rich
It surprised me when the carbide end mill didn't cut, but then again, the drill may have better edge geometry. Definately considering it, but a quick anneal got me to where I needed to be. Thanks!
Reply to
Todd Rich
If you took them up to red heat and *cooled them slowly*, and it didn't help much, then your problem is not hard material. The time you should spend cooling them depends on the alloy. In this case, it depends on the slower-quenching of the alloys involved. For plain carbon steel, you can just heat to red heat and let it cool in air, unless it's very thin. But alloy steels can require a long cooling time.
They're interesting, Todd.
-- Ed Huntress
Reply to
Ed Huntress
Now I'm not following you. If heating them to red heat didn't help, what do you mean by a "quick anneal"?
-- Ed Huntress
Reply to
Ed Huntress
Red hot is actually a fairly large temperature range. The dull red temperature I was talking about probably was in the 1100-1200F range. Glowing, but dull color and not that bright.
By 'quick anneal' I meant that I took it up above the critica/curie point to where the steel reverted to austenite, and then let it air cool. Quick meaning air cool, and not putting it something like ashes or vermiculite to decrease the rate of cooling for a 'full anneal'. Sorry for the bare bones response, but I'm camping and the laptop is running low on the battery.
Reply to
Todd Rich
That's OK, I follow you.
-- Ed Huntress
Reply to
Ed Huntress
What RPM are you running?
Using coolant?
Manual drill press or machine with a feed?
Regards, Joe Agro, Jr. (800) 871-5022 01.908.542.0244 Automatic / Pneumatic Drills:
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Spindle Drills:
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V8013-R
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Reply to
Joe AutoDrill
I was using 3/16" and slightly smaller bits at about 480RPM, using heavy pipe thread cutting oil as a coolant/lubricant. Manual drill press. 1/2 (real) hp motor (claims it is a 3/4 hp). Todd
Reply to
Todd Rich
Should have worked fine as long as the thrust was adequate at around 150-200 lbs. maximum and 100 minimum. Just guestimates.
Also, plenty of coolant as the tool can't possibly get red hot if there is still liquid oil or coolant around it at that speed.
Reply to
Joe AutoDrill

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