OT: tempering bedframe iron

[Bill D]

A bit home shop harry. I need to drill a one inch hole in a bracket already welded up from bedframe mystry metal angle iron. If I heat it up to cherry red and allow to aircool will it be soft enough to drill with HSS? I have used bedframe iron before for non-critical applications. It seems to be like spring steel and somewhat hard to drill. This piece is much harder to drill then what I have used in the past. I would like to get this project done tonight so no buying better iron. I may have to break out the boringhead and use carbide boring bars. I was able to get to 1/2" holes with HSS that now need to be sharpened.
Bill D

 

[DDoug]

A bit home shop harry. I need to drill a one inch hole in a bracket already welded up from bedframe mystry metal angle iron. If I heat it up to cherry red and allow to aircool will it be soft enough to drill with HSS? I have used bedframe iron before for non-critical applications. It seems to be like spring steel and somewhat hard to drill. This piece is much harder to drill then what I have used in the past. I would like to get this project done tonight so no buying better iron. I may have to break out the boringhead and use carbide boring bars. I was able to get to 1/2" holes with HSS that now need to be sharpened.
Bill D

Real machinist's (practical ones) don't mess with "mystery metal".
Why not register over at the hobby forum ?
www.hobby-machinist.com

 

[dalmatiangirl61]

If you have a leftover piece it should be easy enough to try. Carbide, rotabroach, whatever it takes.

 

[winger]

I dealt with mystery metal in a maintenance shop quite often.

Dave

 

[Bill D]

Real machinist's (practical ones) don't mess with "mystery metal".
Why not register over at the hobby forum ?
www.hobby-machinist.com

I agree but why drive 5 miles each way and pay $10.00 for a four inch piece of angle if I already have a piece that should work. At least it will not be 100 until later this week. By then I can go to the steel yard as it will be too hot to continue working in the attic.
Bill D

 

[memphisjed]

drill it like stainless if in doubt. slow rpm and heavy hand.

 

[TGTool]

Short answer. Heating to cherry red and letting it cool naturally should soften it. Heat a fairly wide area so adjacent metal doesn't draw heat away too quickly.

 

[Asquith]

Use a masonry drill.

 

[Scottl]

In addition to heating the spot on the angle iron, take a short chunk of at least 1" diameter steel and heat it red hot also and then place it end first on the heated spot. The additional mass will ensure slower cooling and should anneal the spot.

 

[4GSR]

Yeah, Slooow cooling is important. Air cool is just going to make it hard again. That stuff is very high carbon steel, like a 1060-1090 grade steel.

 

[DDoug]

I agree but why drive 5 miles each way and pay $10.00 for a four inch piece of angle if I already have a piece that should work. At least it will not be 100 until later this week. By then I can go to the steel yard as it will be too hot to continue working in the attic.
Bill D

Because this subject has been hashed to death in the past.
The answer has always been the same, leave it alone.
But apparently you want to bring it up new yet again, just because your being cheap.

 

[michiganbuck]

Slow RPM drilling with a lot of pressure often does better on a tough mystery metal and can take less time than annealing it. An older 1/2" drill motor often turns slower. Drill a pre-drill a 1/4" hole first with slow rpm may assure that you don't work-harden it.
*Note; If it files, then slow rpm drilling should work.

Torch the drill spot/place to cherry, and clamp a couple of ceramic tiles one on each side to let it cool slowly may work. The part could warp a little.

 

[mfisher]

How critical is size/hole quality? Heat to cherry, then hit the oxygen valve while making a circular motion with your arm. I usually go counter clockwise, but I doubt that matters much. :-)

 

[gbent]

Do not heat it cherry red! You only want to temper the spot. You don't have to worry about an air quench hardening the part if you don't heat it above 1300F. Heat the part to a dull red in dim light, which will be about 1,000F.

 

[Ries]

Drilling hard things isnt so hard- unless all you have is woodworking tools. Under 100 rpm, use lube, and lots of downfeed pressure. Plus, it helps to know how to sharpen drill bits.

 

[DDoug]

Here's your sign:

Bed Frame, what material? - Weld Talk Message Boards

And:

Bed frame steel...is it really as bad as it seems? - The Home Shop Machinist & Machinist's Workshop Magazine's BBS

But wait, there's more:

BED FRAME ANGLE IRON: what kind of metal is it?

There is something about this metal but I can't figure out it's welding characteristics or composition. Any ideas?

weldingweb.com

 

[Joe Gwinn]

drill it like stainless if in doubt. slow rpm and heavy hand.

Yes. I never had any problem drilling bedframe steel with HSS drill bits, cobalt usually, from the local hardware store. I had to drill the frame rails so I could bolt them together, so things wouldn't creep apart over time. Slow and heavy, with lots of black sulfur oil.

 

[richard newman]

Doug, you woulda made a great reference librarian!

 

[DDoug]

Doug, you woulda made a great reference librarian!

It took all of qty (30) seconds....Why the OP thinks they
need a custom answer just for them is beyond me.
Selfish is all I can think of.

 

[Bill D]

It took all of qty (30) seconds....Why the OP thinks they
need a custom answer just for them is beyond me.
Selfish is all I can think of.

I had tried the slow, high pressure, good cutting oil techniques that have worked for me in the past with mystery metal. This metal is beyond that. All the info I could find was how to draw temper to make a chisel or knife from scrap. I am not a metalufgist but I understand enough to know carbon contet makes things harder and more brittle.
I had seen both of those links and the only info in them about drilling is to use a hand cranked post drill with lots of lube. Others say they drill it fine with a sharp hss bit.
I asked because in the past I have tempered bearing races so I can drill the inner bore to make bearing pushers of a perfect size.
I realized I was fixated on drilling. I took things apart more and did this on my mill with a carbide endmill interpolating a circle manually. I had planned to drill and tap a hole but I realized I could not tap this material
Bill D