drilling steel

Midget

Midget

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Jun 1, 2002
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i want to drill two, big holes into the handle of my strider DB to lighten it out a bit. the handles are .25" thick, S30V, and heat treated.

think i can do it?

what will i need? i don't have a drill press, unfortunately.

are there any special bits i can use to get through all that steel?


or maybe i should just scrap the plan altogether?
 
carbide drills would be what i would try. you most likely would have to get them from a machine tool supplier, you wont find them at the home depot.
 
I think the blade is S30V. The handles are probably aluminum. Can you post a picture?
Bill
 
sure.

blade is s30v.

no handles-- it's cord wrapped.

i'm going to cut the cord wrap, drill the holes, then rewrap.

from "EDC-- what's in your pockets?" thread on the general discussion:

edc6nq.jpg
 
You will need carbide drill bits-several of them. Perhaps a local machine shop could do it for you.
Bill
 
i've heard that cobalt drill bits do well on really hard metals, can anyone back this up? a friend told me they worked well for drilling out hardened bolts
 
Carbide, and don't think about doing it with a hand drill. You will need either a drill press or a milling machine. S30V after heat treat is around Rc60 on the hardness scale, right there with a file. Carbide or diamond tipped is the only stuff that will cut that. You probably want a carbide spade bit that you can source from msc.com. They won't be cheap.
 
I have drilled hardened steel with carbide masonry bits. You will burn up several of them but still less expensive than specialty bits and available at the local hardware store. Use a drill press and plenty of cutting fluid.
 
Yeah, if you don't care about the exact size of the hole, get some 1/4" and 3/8" or 1/2" carbide masonry bits. I also highly recommend getting a Drill Doctor or other drill bit sharpener. Sharpen your bits before use and touch up as soon as they stop cutting easily. Start with the 1/4" to make a pilot hole, then move up to 3/8", then 1/2". When the bit breaks through the steel, reduce the pressure and finish the hole with very light pressure. This is when the carbide bit will most likely chip and shatter if you're not careful.

That said, before you get started calculate how much weight you're saving (using the volume of your holes and the density of steel) and see if it's worth the time and trouble. You might find the weight savings to be less than you think.
 
Really to reduce heat and the chance of burn marking the blade you are better off to drill those holes in steps. What I mean is 1/8 first then 3/16 then 1/4 if the hole is going to be big. If not you will probably burn out the bit after the second hole anyways if it even makes it through the second one before breaking. The bigger the bit the more heat. You want to crank your drill press up to a higher speed for these bits also and let the bit do the work without pushing it in faster than it can clear out the debris. You also want to be very careful on the exit out the other side. Place a scrap piece of steel under the blade handle to support it and clamp both the blade and it down on the table.

If it were me and I was limited in the number of bits I had, I think I'd drill all the holes just short of exiting the other side first and then drill the exits out. This way even if the bit does shatter on you you can probably still manage to use it to get through the holes.

STR
 
I also would start with a small concrete bit and not go all the way through just break through and turn over getting a hour glass type shape to the hole. When at the hardware store getting your bit/bits take a look at the Dremel section I think I'd try those bullet shaped ceramics to make the holes larger. I'd get a few of them. Dremel also has a few other things for harden steel take a look I've only used the ceramics though.
 
Seems like a pretty small knife. How much weight are you looking to drop? Wouldn't you compromise strength before you got a significant weight loss?
 
If you're carring all that stuff on you everyday, a few holes in that handle isn't going to make much difference. I've said this before, "I have *improved* many a knife right into the garbage can"
 
Carbide, or cobalt bits (by the way, you really need to be using a drill press to do that).
 
Hello Midget, Spot annealing should be sufficient for any steel except exotic blends. Concrete bits really are for concrete. You may have to use a tungsten bit or some other type end for some steel blends, but usually a standard beveled bit will work. The steel might require a different bit angle grind. Lot of info in gunsmithing books for drilling hardened steel. Have fun, Tumblebug
 
cutting fluid aplied with a small disp. paintbrush will be your greatest friend when drilling steel. Oil or water are not a substitute for cutting fluid. You can buy it at napa or similer stores. good luck :)
 
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