Drilling Steel

[Byron Trantham]

I want to drill 1/2"(?) holes through the end of my older Bessy clamps to accommodate the newer clips. I haven't tried it yet but I expect that the steel is hard:eek: What drill bit do you guys recommend for doing this? I have a drill press. I also expect that at least two sizes should be used; a pilot hole and then the final hole.

BTW, I contacted Bessy for these clips as recommended by someone here and sure enough, they asked me how many do I need and where to ship them.

Man this board is cool!!!!!!!!!:D

[Dan Cameron]

I would think that a good HSS twist drill would do it. Use a slow speed and lubricate with oil.

[Glenn Clabo]

HSS will work but Cobalt drill bits work well...~600 rpm...coolant like Cool Tool and don't wimp out on the feed rate. Stainless work hardens if you use a slow (rubbing) feed rate.

[Brian Hale]

Please make sure you clamp that thing down to the table REAL good and use a solid fence to stop it from rotating. Keep the head of the clamp on the left hand side of the drill press so that if something nasty happens, it'll hit the column and not you.

Just about any oil will work for a lubricant but use plenty.

A pilot hole is OK but keep it small, 1/8" or so.

Run the bit as slow as you can. I'd like to see 150 rpm.

Pull the drill out of the work often to clear the chips.

Good luck

Brian :)

[Dev Emch]

Hi Bryon....

Check out my personal (not selling yada here) website for my loader project.

http://www.users.qwest.net/~emchd/D17_Loader_Project/henry_loader.htm (http://www.users.qwest.net/%7Eemchd/D17_Loader_Project/henry_loader.htm)

You will see me drilling a 1/2 inch ream bore pilot hole for later line boring. But you asked on makin' holes.

First, you need to mark out where the hole goes. Then using a center punch or prick punch, tap an indictor pip where you wish to drill. Then, using a special drill bit, bore a counter bore center hole. This drill bit is called a centering bit and is used to drill lathe centers in steel. A lathe center is a 60 degree counter bore with a central centering bore. Here, you only need to bore down about a 1/4 inch or so as your not using the center.

These bits are EXTREMELY rigid for what they do. They will not wander as will normal drill bits. Normal drill bits love to wonder on steel. This is a machinist bit and you get them at tool suppliers, ebay, etc. The imports are rather cheap in price so its not a major expense and you should have one. A 1/4 inch shank will work just fine. They have bits on both ends by the way.

Once you have your center hole bored, time to move on. And not all the way through by the way. Switch over to say a 1/16 to 1/8 in drill bit. Use an acid brush and a pipe cap to aide you here. Fill the pipe cap or tuna fish can with cutting oil and brush a bit on the hole as you go. Bacon fat works aboslute wonders when cutting nice holes into steel by the way! Also works wonders in tapping threads and cutting threads in steel as well. Bore all the way through this time. The bit should self center itself in the bottom of the center drill hole. That is why you should not drill all the way through with your center drill bit.

Now, using your pipe cap full of bacon fat and an acid brush, repeat the process until you work your way up to say 31/64 ths using your drill index. You dont need to use every size in there but reasonably keep increasing the bit size each step of the way.

Drill bits do not drill nice round holes. Fancy That! Reamers to that! But a reamer needs to remove a minimal amount of material. So that is why I bored the holes out to 31/64 th and then changed over to a reamer. Reamers also dont like fast speeds which are used with high speed drill bits. So knock the speed down a bit. Use plenty of baco-bits on your acid brush and slowly but constanly advance the reamer through the hole.

The result is a nice, super smooth, super round hole 1/2 inch in diameter with no bugger edges or egg shaped circumferences. Very nice!

That is all there is to it. Clean up the metal shavings as these can be sharp and hurt the dog's feet. Oh ya, you will get a kick out of the helical chips that wind out of the drill press when you cut your first steel hole. Dont be worried here, that is normal. Also, a bit of smoking will be normal. Use your judgement here. If the bit is turning blue, I guess that may be a bit to much down force or the bit is a bit dull, RIGHT?

Good Luck...