Recommendation? I cannot drill this Sam I am...

[spareparts]

I cannot drill this in a house
I cannot drill this with a mouse...

Ok, sorry but I'm at my wits end. I have a piece of 15N20 from Aldo, only .05" thick (not a typo) and I can't drill holes in it. At this point I've spent more on drill bits than the damn steel is worth.

I don't have any high end bits like tungsten carbide, but have tried all the flavors available at the local hardware store with the same results. I get halfway through, so lets say .025" and then the bit stops cutting.

I've tried with oil and dry, same result. I've tried max speed on the drill press, to the slowest setting and several in between. Played with tbe tension on the drill press belt.

The steel cuts just fine on the bandsaw and a file bites it easily so I don't think it is hardened. And the half of the hole that the drill bit cuts, goes in real easy, just like all rhe other steel I've drilled in the past...but then just stops cutting.

Thanks, guys. I'm probably going to slap myself when you tell me some common sense thing Im either doing wrong or overlooking.

 

[E.Carlson]

Not sure about aldos, but the 15n20 from alpha comes from the mill at around 43 rc. Quite a bit harder than most other common stuff you would get like O1or 1084. My cheaper bits wouldn't touch it.
You need cobalt bits and slow speed. I order them in 10 packs off Amazon in the sizes I use. I also have a cobalt step bit for large weight reduction and epoxy voids.
I

 

[LARRYZ10]

If you go online there is a company called Drill bit city and on their webpage is a link on the left column for Drill bit city II at which you buy reground tungsten carbide bits in lots of 5 or 10 each . They come in metric, American Standard fractional , decimal, numbered, and letter drills. I have used them for years. They have short shanks and will drill almost anything. Like most Tungsten drills they are somewhat brittle so it pays to buy them 5 or 10 at a time in the sizes most knife makers use. I like to buy "letter F" drills to drill tangs for 1/4 inch pins. You can buy other drills that are slightly larger than 1/8 " or 5/32" by using numbered drills that a couple thousands larger. I use a lot of number 12 and number 30 drills for knife projects. This information may help some of you with tough drilling jobs. Larry

 

[DevinT]

I cannot drill this in a house
I cannot drill this with a mouse...

Ok, sorry but I'm at my wits end. I have a piece of 15N20 from Aldo, only .05" thick (not a typo) and I can't drill holes in it. At this point I've spent more on drill bits than the damn steel is worth.

I don't have any high end bits like tungsten carbide, but have tried all the flavors available at the local hardware store with the same results. I get halfway through, so lets say .025" and then the bit stops cutting.

I've tried with oil and dry, same result. I've tried max speed on the drill press, to the slowest setting and several in between. Played with tbe tension on the drill press belt.

The steel cuts just fine on the bandsaw and a file bites it easily so I don't think it is hardened. And the half of the hole that the drill bit cuts, goes in real easy, just like all rhe other steel I've drilled in the past...but then just stops cutting.

Thanks, guys. I'm probably going to slap myself when you tell me some common sense thing Im either doing wrong or overlooking.

Reverse the direction of the motor so it runs the correct way. Kidding, Larry’s got you covered.

Hoss

 

[spareparts]

Thanks, Larry, awesome find.

 

[Ken H>]

Reverse the direction of the motor so it runs the correct way. Kidding, Larry’s got you covered. Hoss

That's funny..... but it happens. Back in '90's when living in Guatemala I got a radio call from another boater wanting to borrow a 3/8" drill bit. Said he had some of the hardest SS he'd ever seen. He's already burnt 3 drill bits trying to drill the material and it was going really slow, and could he borrow a couple of bits from me? We chatted a bit, then I suggested he check the rotation of his drill motor. A few minutes he called back..... Yep, drill motor was in reverse. Of course since the discussion was on radio, everybody around heard his problems..... and solution.

Later

 

[Lieblad]

Ha! Bizarre as it is, Folks running reverse and not aware is more common than you might think.
Anyway, Sounds like your steel its workhardening. Its a common thing drilling tool & stainless steels.
Use good bits, lube, Get on the right speed & downfeed pressure and never let a bit spin without cutting.

 

[mete]

I've come across that problem in the woodworking business with insert tooling .Reversing the cutter head does really change the process !! I helped a salesman save the customer's feelings when I told him to go to the customer and explain exactly how to set up the cutter head. Without letting him see he reversed the head back to normal.

Before I became a metallurgist I met 'work hardening ' and was very confused at starting a hole with no problem then suddenly could not proceed ! Yes some alloys are very sensitive to that. The 300 stainless steels can't be HT'd but 301 purchased in 'full hard ' , 'half hard ' etc can be excellent for even things like springs.

 

[DeadboxHero]

Slow your drill speed down to 500ish rpm
If you're running the drill faster it ruins the drill bits, Burnes them out, dulls faster
Also I'd sharpen your bits

Cobalt bits should work great before heat treatment.
Don't waste time with HSS or titanium nitrided coated bits. Just use cobalts and then keep some solid Carbides for just in case.

I learned this all the hard way.
Had the same problem.

(Aw I'm daft, just read you played with all the speeds, carbide it is!)

 

[kuraki]

Thanks LARRYZ10 that drillbit city is an excellent resource. If you got one for carbide reamers I'm all ears

 

[Willie71]

Option two is to soak 15n20 at 1200f for 2h before working it. A subcritical anneal is all that’s needed to soften it up.