Metal working question

runningboar

runningboar

Joined
May 27, 2006
Messages
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I have a part that I want to drill, it is hardened steel, a file will just barely cut it. I tried to drill with a standard HSS bit and it would just slide around on it and I would rather not anneal the part and have to reharden it. Anybody have any suggestions as to what kind of bit to use or any tips and tricks. I am not free handing this, I have a press and a vice.

Thanks in advance, Chris
 
I may be telling you how to suck eggs here but try going through with a much smaller bit first on a fairly slow speed with plenty of lubricant.
Once you have your pilot hole then try your actual hole size bit again but still fairly low speed with pleny of lube !!!!
 
I am trying to drill a fairly small hole and one of the problems I am having is the bit flexing and sliding around. I tried to hit it with a center punch to get the bit to stay in one place and it will still move around. I need the hole to be fairly precise, I have thought about chucking up a diamond pointed dremel bit to start the hole, any thoughts. Chris
 
I am kinda new to all of this but maybe cobalt bits, they have a rockwell hardness of 65.5 to 67, so being that the hardness of the bit should be harder than your hardened steel i would think it would work. Once again this is just a guess based on my knowledge of the construction industry and how strong cobalt bits are.
 
You should be using a carbide drill bit.Or , depending on the steel, you could spot anneal it.
 
Yeah the dremmel might work. You may of actually work hardened the steel when you were allowing the bit to slide around so just removing a little of the surface steel with the dremmel could solve the problem. what size hole are you drilling ?
 
Use a carbide drill bit, run it at high speed with light pressure DO NOT PUSH OR FORCE BIT, must be flooded with cutting oil. USE EYE PROTECTION WHILE DOING THIS STEP. Be patient.
 
mete said:
Or , depending on the steel, you could spot anneal it.
Click to expand...

Trying to stay away from that, what I am wanting to do is to drill and install a set screw in a hammer where it is engaged by the sear, so I can adjust the sear contact, which will result in an adjustable trigger pull. If I anneal it and don't harden it correctly it will wear quickly and if I get it too hard the engagement point is liable to chip and break off. Right now I have a glob of JB weld that I have cut, filed and sanded to the pull I want and in the real world that is probably good enough and will last forever but I would like to do a more professional job and if I install the set screw it will be adjustable. Chris
 
runningboar said:
Trying to stay away from that, what I am wanting to do is to drill and install a set screw in a hammer where it is engaged by the sear, so I can adjust the sear contact, which will result in an adjustable trigger pull. If I anneal it and don't harden it correctly it will wear quickly and if I get it too hard the engagement point is liable to chip and break off. Right now I have a glob of JB weld that I have cut, filed and sanded to the pull I want and in the real world that is probably good enough and will last forever but I would like to do a more professional job and if I install the set screw it will be adjustable. Chris
Click to expand...

I really believe that a cobalt bit would do the job as I stated earlier. They are designed for hardened steel, titanium, wood, plastic, etc.
 
I had a similar problem last week. Try the cobalt bit or the carbide, with SLOW speed and heavy pressure. That is how you should drill steel. Like someone already said, you may have work hardened it. What size hole is this we're talking anyway? Is is smaller than a #40? If not start with a #40 then go up in size slowly, but remember to go Slow with heavy pressure, not too heavy though, it is a small bit. Hope this helps. I had a similar problem last week.
 
I would NOT use heavy pressure with extremely small drill bits.

If you are unable to center punch it, that tells you something.
You can use a carbide dremel cutter, the one with the point to make the indent for the bit to catch. Also, dremel makes little diamond bits.

So, you are drilling and then tapping? (Set screw)
Hmmm.... even if you get it drilled, tapping into hardened steel could be an iffy propostion.

Well, I hate to say it, but..............

You could anneal the whole piece, drill and tap it, then re-harden it??
 
Yeah, skunk looking like that is what it is going to come down to, I guess I shouldn't be so particualer it is a cheap and plentiful part and if I eff it up I can just get another. BTW it is a spyder hammer, polished to a mirror and the sweetest mechanical pull I have ever felt, I just don't like the JB, and it would be be cool to be able to adjust just by pulling your hammer out the back.:grumpy: Chris
 
OH, OK....gotcha.
That is probably a Stainless type of alloy, and that is why you are having trouble with the bit dancing. Stainless isn't necessarily hard, it just has some slippery properties when it comes to cutting and drilling the darn stuff.

Cobalt or Carbide bit may be the answer!

Edit: Chris, go see your armorers or your motor pool mechanics, show them your stripes,
and tell them there is a couple of 6-packs for them if they can drill and tap that bad boy!
 
SkunkWerX said:
Edit: Chris, go see your armorers or your motor pool mechanics, show them your stripes,
and tell them there is a couple of 6-packs for them if they can drill and tap that bad boy!
Click to expand...

Don't mean to sound concieted but those guys come to me.:o I just thought there might be a trick I didn't know about besides annealing. It's all good, I am going to leave the JB on it for a while until I can see clearly where the sear rubs on the underside, mark it and lay the carbide to it. I don't have a thing but my time in this gun anyway, and I can buy a new hammer for 13 bucks.:thumbup: Chris
 
It is hard for me to understand why you could not
spot anneal. Are you thinking that the annealed area
will be too large? Keep the rest of the metal wrapped
in wet cloth.

If you anneal a very small spot, and then drill out that
area, what is the problem? The rest of the surrounding
metal would still be pretty hard.

You could do it in several stages: anneal, drill, anneal, drill etc.

I am not a very good Mr Fixit, nor a machinist, nor gunsmith.
These are just ideas that might help you.

Due to the danger involved, I would never mess with a Trigger,
but I know some home gunsmiths do it successfully.
 
You will have to drill super slow. Start drilling it by barely turning the bit and very slowly increase speed. When it begins to cut keep it at that speed and go no faster, and if you have cutting fluid use it.
 
You may want to center drill it first. If you have access to one, a Bridgeport or other manual mill is a big help (more solid and precise than a drill press). I'd peck at it a little at a time.

But if your going to tap it also, you may want a machinist to do it. Hand taping hard materials is a real bear.
 
Two things, neither of which I have tried personally.
The first is chuck up a nail of appropriate size in the press and you will get a spot anneal right where you want to drill. Then drill it.

Old time smiths would drill a hole 90 degrees off of sear engagement surface, and press fit a pin. This would limit sear engagement without changing the actual working surface. Then they would file the pin down until they had the fit they needed. Later, more could be taken off if there was insufficient engagement.
 
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