Drilling through Stainless Steel

[ArtS]

I put a piece of stainless steel between the layers of leather in some of my holsters. The problem that I have is drilling a hole through it. It's a thin piece of strapping, maybe 1/16 inch thick. I just wear out drills. There must be something I'm doing wrong. I dip it in water every so often to keep it cool. I need some advice please.

Help please.

ArtS

[BradB]

I put a piece of stainless steel between the layers of leather in some of my holsters. The problem that I have is drilling a hole through it. It's a thin piece of strapping, maybe 1/16 inch thick. I just wear out drills. There must be something I'm doing wrong. I dip it in water every so often to keep it cool. I need some advice please.

Help please.

ArtS

Are you using metal drill bits and not wood? Maybe try a diamond tipped drill bit?

[Rawhide]

Stainless is extremely hard to drill. I'm not sure that "home depot" type drill bits will do the trick, repeatedly anyway.

You may need to try some diamond tipped bits from a place like woodcraft or go to a metal fab shop and ask a ton of questions.

Marlon

Edited September 10, 2008 by Rawhide

[bruce johnson]

Art,

I had the same problem with the SS strapping on the dee and straps I use on my saddles for breast collar dees. I use 2 holes and rivets to make them more secure and keep them from torquing. The titanium coated bits would maybe be good for one or two straps, even with oils/water/slow speed. Get them hot and just watch the drill bits melt and puddle on the strapping like the wicked witch of the west. The heavier strapping from my preferred source was a 2 bitter sometimes. I took to punching the holes and pounding the "splash" flat.

Then enter my good pal Littlejohn from Detroit. A metal workin' man who solved my problem. (side note - Anyone heard from him lately??) As some stainless heats up it gets harder. He advised me to get the cobalt bits. They cost me about $5-6 bucks each. I bought a few and still am using the first one. They do a good job on the stainless. They eat old copper rivets like marshmallows. The real deal.

[steveh]

Try using a colbalt bit in a drill press, with a cutting fluid applied while drilling. The Chromium in Stainless makes it very hard.

[wolvenstien]

LOL

Yeah... Stainless is one of the harder to drill.

I came into the same situation a short while back. I had several stainless coasters, about 4 inch across, and about a 1/4 inch thick. I had titanium bits that I figured would be cool to use with my drill press. I melted them. I then used a "FOR METAL" bit I got in a package for tapping metal... it melted worse then the titanium bits... I started to call around to the local metal shops to see if I could get one of them to cut the holes I needed. I finally got to talk to a shop boss and explained the situation to him and explained i needed them done by 6 that evening. He had already closed the shop but would be happy to call someone back in to do it, but we were talking a couple hundred dollars just for 12 holes. Then he offered to leave me a COBALT bit at the receptions desk for me to come by and pick up.

I ran over there and got the cobalt bit and ran back to the house to drill the holes... It melted on me too.

So needless to say, I did not get the holes drilled.

But I do know cobalt and titanium bits will not work on cutting holes in 1/4 inch stainless....

Good luck, and please post back when you find something that works.

guess i took longer than Bruce and Steve....

What type of cooling lube you talking about? Like I said... the cobalt melted on me...

Edited September 10, 2008 by wolvenstien

[ArtS]

Thanks everyone. I'll call around tomorrow to find a cobalt bit.

Thanks!

ArtS

[Luke Hatley]

this has workrd for me. heat the SS with a torch, red hot then use a punch to make the hole'

[steveh]

wolfenstien,

I have drilled stainless quite a bit, use a high quality usa cobalt bit, do not know name brand off hand, the cutting fluid is a product like majic tap or crc in a liquid or aresol. use a vise or hold down to hold your work solid,in a drill press at low speed keep the coolent on your work. I have drilled 1/2 Plate this way.

[BarryKing]

Try buying at Fastenal, if there is one in your area(they seem to be across the country). You may also use a solid carbide drill bit. These are a little harder than the cobalt ones. Always use a cutting fluid on stainless. Also, run your RPM at about 1/2 as what you would on mild steel. This is where the steel tends to heat up and work harden. If you are just drilling very thin steel, ask for a "center drill". These tend not to "suck into" the steel as much as a drill bit.

[ArtS]

Thanks Barry.

ArtS

[Trevor]

Hi there

All you need to do is make sure that

1. Your drill bit is sharp.

2. The drill needs to be made from "High Speed Steel" marked "HSS" on the shank.

3. Be aware of the heat that the drill will generate which could damage the leather.

Good luck

Trevor

"Way Down Under"

[GampasShop]

The #1 problem most people have when drilling thru SS is the drill speed. Keep your drill RPM's low and any bit will drill it. If you just pull the trigger all the way you will go thru bits faster than you can chuck it up. When drilling SS you want your RPM's somewhere in the 350-500 range, which if using a 3/8 drill most of them are geared in the 1500 rpm top range. Just take it slow and when it is removing chips good, DO NOT GO ANY FASTER.

Many years of working as an electrician in meat packing facilities has taught me this. Many of the guys I worked with never did catch on.

[Art]

Hi Art,

Big blocks of stainless should be normalized or annealed before machining, but when I have had to tackle heat treated stuff, I go to a company named Guhring for bits. I get bits and end mills from them that are made of micro fine carbide and coated with a multi-layers of titanium nitride and titanium aluminum nitride. These things are run at high speed and feed rates and without coolant (air jet cooling is ok though), this is opposite to what we learned for HSS bits. I haven't bought in a while and am sure they have improved even more. They also produce PCD (polycrystalline diamond) bits, but I have never wanted to drill a hole in carbide. Down side is the cost, an 1/8" jobber length bit costs around $50-$60, however will last thousands or holes in thin stainless, and they can be resharpened (by Guhring). Run 'em fast, no liquid, it is a little scary at first, especially when you are abusing the crud out of a $60 bit or $200 end mill. Don't do anything over HRC 90 (I'm serious), yes, I did type ninety. The folks at Guhring tech support are good too.

Art

I put a piece of stainless steel between the layers of leather in some of my holsters. The problem that I have is drilling a hole through it. It's a thin piece of strapping, maybe 1/16 inch thick. I just wear out drills. There must be something I'm doing wrong. I dip it in water every so often to keep it cool. I need some advice please.

Help please.

ArtS

[ArtS]

Thanks. I see one thing I was doing wrong right off - I was drilling too fast. I was cooling with water but I'll get some cooling oil or fluid.

The $60-$200 are too steep for me but I'm going to go get a cobalt bit. I only need the one size for the snap shaft to fit through. I found a Fastenal near me.

Thanks again everyone.

Art

[Davy]

I drill ss every other day . Its no big deal if you go with Trevors instructions , he was bang on with what he advised . Dont worry about coolant unless its thick gauge steel . Should only take half a sec to drill through 1.5mm ss .

[WilliamWood]

OK. First of all, you will have to slow the drill down as slow as it will go. (For a 1/8", I'd advise no more than 200 RPM.) Use a good quality High Speed Steel drill bit that is very sharp. Use a fair amount of feed pressure (how hard you push it into the work). Practice on a scrap of the Stainless. Stainless steel comes in many grades. If it is thin sheet, it probably is Grade 302 or 304. That is type used to make stainless steel food prep tables and equipment. 302-304 Stainless is stainless (actually it is stain resistant - ALL steel will corrode or rust under the right conditions) because it has a very high percentage of both nickel and chromium. Those two metals also make it very susceptable to a condition known as "work hardening" if the drill is allowed to rotate on the surface at enough speed without removing metal. As it spins on the surface, it gets that spot hot from the friction. The metal under the drill bit actually gets harder than the bit. DO NOT try a carbide tipped or a "Diamond" bit as the stainless in these grades is so "gummy" it will actually break down the carbide and "snatch" diamond dust out of the drill bit. It will ruin one of these hideously expensive bits instantly! Usually, if several holes are needed, I'd advise a punch of the type used in sheet metal fabrication. (A good Air Conditioning and Sheet Metal shop can help out here, and it's a bargan at almost any price. Otherwise, just remember: SLOW RPMs, Heavy Feed , Sharp HS Steel drill bit. (How do I know? 30 years as a Tool and Die Machinist and Gunsmith.) Also: Clamp the piece down firmly when drilling. The drill bit WILL grab the piece when it cuts through. Use a drill press if possible and clamp down tight on the table. If a hand drill is used, get a variable speed, run slow, and put the piece in a padded metalworking vise.

I try to avoid 302 or 304 if possible........... too old for that kind of stress and frustration....

[fire]

I've had good luck using step bits for stainless.

[Sharpshooter]

My shop is attached to a knife company... they drill all different sorts of stainless steels after heat treat so it is possible.

Drill speed is critical... also with very thin materials it will grab the bit as you poke through. 1/16" is pretty thin and you MAY be better off punching through like we do with leather. I don't think you mentioned the hole size...

The Knife shop uses Carbide Bits, not carbide tips, carbide bits. If you can't find a specific size, let me know and I'll find the source for you.

Damn.... I'm pretty spoiled with my setup... none of these things are problems for me so long as I

m willing to walk a whole 30 feet. Let me know if I can help.

[ArtS]

Thanks everyone for the advice and help.

The Major took care of me as far as the bit and now I'm going to make myself a holster for my Makarov .380. So I'm going to try it out and also a new design for the thumb break.

Well not a new design - just new for me but old for the Ross Company.

I'll post it when finished.

Thanks,

Art

[dcallagher]

My "day job" is in maintenance in a food grade production facility. I work with fabricating, welding, machining, repairing grades and thicknessess of stainless steel all day.

What most folks have said above I agree with completely. Here's my two cents.

#1 The most important thing is 6% or higher content cobalt steel alloy drill bit.

#2 Go slow. A variable speed hand drill is usually too fast. A drill press is preferable.

#3 Use cutting fluid.

#4 Use pressure. (again, drill press)

#5 Mark your drill point start on your material with a good center punch.

#6 Step up from a smaller bit to larger. (1/4" hole or larger, start with a smaller drill first).

#7 If drilling thin material back it up with something harder than plywood, like aluminum plate.

If you need to make larger (larger than 1/2") holes through thin material. Start with a 3/16" cobalt drill bit to make your starter hole then change out to a stepped drill bit. Don't use the thick backing piece for working with the step drill bit. Works real well for me.

http://www.grainger.com/Grainger/items/5YR46

http://www.grainger.com/Grainger/items/2CJR6

[WilliamWood]

Thanks everyone for the advice and help.

The Major took care of me as far as the bit and now I'm going to make myself a holster for my Makarov .380. So I'm going to try it out and also a new design for the thumb break.

Well not a new design - just new for me but old for the Ross Company.

I'll post it when finished.

Thanks,

Art

Hi Art, Did you ever solve the problem of drilling the stainless steel? WilliamWood