Drilling a hole in tool grade steel

Sep 22, 2010 10 Replies

My 1978 Craftsman loping sheers have a loose handle so I decided to drill and bolt them together. Using a drill press at 300 RPM and cutting oil for lubrication I managed to kill 4 HS dewalt bits and one titanium while only making it about one third the way through the 3/16" tang. Damn that is some hard steel.



I managed to secure the handle using a self tapper through the hollow shaft and tightened against the steel tang but I know that is going to last very long. It will do for a few jobs



Trying to make a hole for just a small machine thread 2/16 or so screw? Any suggestions?



Carbide tipped tools are used to mill just about any grade of steel on CNC machines.

Alternatively, since the tang doesn't need the temper, if OP has small-tip torch can heat a small spot to soften it.

Generally, though, if they're wooden handles, the problem is that they have compressed or otherwise deteriorated from the inside and the fix is to replace the handles. Given they're 30 yrs old, that's not a bad lifetime if so...

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If the steel is hardened, you need a carbide drill bit or to anneal it.

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Glue. Or wedges (they work for axe handles).

I appreciate the positive responses and will look for a carbide bit.

Maybe I did not provide enough information. The handles are hollow steel tubing, not wood and the end of the tube is capped with a slotted cap into which the tang fits. I really don't understand how they lasted this long. Friction fit I guess.

These old shears are anvil style and have outlasted 2 newer bypass ones. Even at their age I consider them worth fixing. I doubt the Chinese crap of today is of such quality.

I was not stupid enough to try this with a drill. I was using a Delta table top drill press and the belt is set in the 300 RPM pulleys. That speed increases the life of the bits and does not require cutting oil for light metal.

The 2/16 was a typo. I meant 3/16. For the one or two of you that may not know that diameter is half way between 1/8" and 1/4".

You need to use oil. You need to keep it cool. Why don't you see if there is some other way to secure the handles, epoxy maybe?

I'm with you, a sharp drill and some more pressure. More pressure on the quill sounds write, to me. "He who hesitates, is hardened."

Take it to a welding shop. Those places charge a lot, but this is probably a 5 to 10 minute job with a torch. Even if they charge $50 an hour, your in the $10 range.

I have used carbide tipped concrete bits on hard steel, but by the time you buy a bit and maybe ruin it, just let the pros do this job.

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