Drilling spring steel

[Jordan Baker]

Hi everyone

I picked up some spring steel (blued tempered) today to make up some bren mount trigger springs I needed. However I can't for the life of me get the drill bit to drill them. Do I have to remove the temper and if so how do I do that. And more importantly how do I put the temper back in.

Or would I be better to use some kind of press and puch out the holes. If this is the better way does someone on the forum have such a thing and could I mail you the parts to punch for me.

Any help is most appreciated.

[chris vickery]

Jordan, punching them in an ironworker is the easiest way. Surely in your area a metal fab shop has one of these machines.
Aside from that you can try to do youself by annealing the metal at the ends where you want to drill. You need to heat up to a dull red and let air cool. I believe you can try to temper again by re-heating and quenching quickly in oil.

[mike mckinley]

hi jordan

chris is correct. if you really want to drill them out there are bits available that will work with spring steel. i was working on a roll machine in a local paper mill and had to drill and tap into the gear cases. we had to order special bits to do the drilling. now, i'm not sure what the difference is on the brinnel scale between spring steel, and ht forged steel, but i will tell you that ordinary steel bits wouldn't even scratch the surface of these cases. i would suggest you contact your local supply house and ask them for an option. another point, i have used bits by several manufacturer's, and i have found that bits made by skf seem to work best, and last longer. mike

[Alex Blair (RIP)]

Jordan..
Try a cobalt steel bit...They are expensive but should work..and alternative would to be to grind a hole in them with a dremal and pointed shaped diamond tipped grinding stone.

Mike would probably hammer a hole in them with a lobster claw..

[Jordan Baker]

HI guys.

Thanks for the tips. My problem in regards to shops is I don't know of any in my area that are good to deal with. In the past when ever I have called, I either have had people come across as being rude or just not interested in what im trying to do. I figure if they are like that then they will not get my buisness.

I did read on another forum about using a blunted nail in a drill press to heat up the area to be drilled. This would do a spot temper removal.

If I have no luck with the drilling then i will search out a punch.

On a side note, can anyone guess what these are for?

[rob love]

Originally posted by Jordan Baker


On a side note, can anyone guess what these are for?

Likely for the brass Bren mount castings that Rob was making up.

Personally, I would just melt a drill bit through it on the old drill press. It will get hotter than h***, but the metal will give way before the drill bit would. I only use the golden coloured drill bits (cobalt) ...gave up on regular high speed steel ones years ago. Seems like you spend more time sharpening them than using them.

[Jordan Baker]

Soooo close Rob. Ok I will give a partial mark for guessing what they are but you don't get the full mark. These ones Rob didn't make and thats all I can say.

I tried drilling agian and it was a no go. So now im going to look for someone with a punch.

[mike mckinley]

Originally posted by Alex Blair
Jordan..
Try a cobalt steel bit...They are expensive but should work..and alternative would to be to grind a hole in them with a dremal and pointed shaped diamond tipped grinding stone.

Mike would probably hammer a hole in them with a lobster claw..

yes...cobalt, that's the ticket. as for the use of marine life and their parts...lobster brine will rust through steel fairly efficiently...but if hammering with a claw, be sure it has a non shock fibreglass handle mike

[Alex Blair (RIP)]

Originally posted by rob love
Likely for the brass Bren mount castings that Rob was making up.

Personally, I would just melt a drill bit through it on the old drill press. It will get hotter than h***, but the metal will give way before the drill bit would. I only use the golden coloured drill bits (cobalt) ...gave up on regular high speed steel ones years ago. Seems like you spend more time sharpening them than using them.

Rob..
Is not the gold bits titanium..??
My titanium set is gold and my cobalt set is blue..
And my lobster claw hammer has shock proof handle,dual exhausts,a Crane roller cam ,a Roots blower, an Allison transmission,with a Dana diff....

[Ian J]

Hi Jordan:
In the toolroom where I used to work years ago, we used Stelite drills to drill into hardened parts. They were a 3 sided drill and were used in a drill press at a high speed. While drilling, the drill would turn red hot but I would keep the presure on and it would drill through. The work has to be securly clamped to the m/c table as it also gets very hot and might catch and spin if not clamped.
I don't think that many shops would be too keen punching your hardened spring steel because of the damage it could do to their punches and dies. You could find that your parts may crack also. You could anneal the part as was described above in a earlier posting. To reharden, you usually heat to cherry red then quench in a special quenching oil, sometimes water can cool the part a bit to quickly and it may crack. After hardening is complete (test by trying to file an edge), all oil should be cleaned off, and the part pollished with fine emery paper to remove any oxides on one face so that you end up with a shiny silver finish, then the part is evenly heated untill the polished silver face of the part turns blue, then quickly quench in the oil until totally cooled. Hopefully the part will not crack and will retain it's flexibility. Getting the temperatures even and correct can be tricky.

[Paul Singleton]

In the past I have drilled leaf springs with a masonary bit. You need to go slowly, if you heat the bit up too much while drilling the cutters will come off. Use cutting oil and make sure the speed on the drill press is not too fast. If your brackets are about the same hardness as leaf springs give it a try, it should work.

Paul

[greg anderson (RIP)]

I made the spring for my Bren holder from an old carpenters saw-this steel will make a spring but you can also drill it

[Godwin Hampton]

Jordan,

Twist drills have a flaw; the point has a small edge between the cutting edges, and on hard surfaces this edge does not dig in to allow the cutting edges to do their thing! Try centre-punching the plate heavily where you want the hole, the 'point' falls in there, allowing the cutting edges to make contact!

Slow speed, and generous amounts of cutting oil.

And Good Luck!

[barriefield-brian]

Sharpen a masonry bit. Use lots of pressure to make it cut then back out before it gets too hot and melts out your carbides. Cool it with cutting oil and repeat. Brian