Drilling titanium

[Chiro75]

Drilling Ti (6Al/4V) with HSS drill bits: good or bad idea? Do you need carbide bits for it?

 

[rhrocker]

They usually won't last very long, but it can be done with HHS. I like using cobalt drills (screw machine type, much shorter, from places like MSC). I use a lube (I keep a acid brush in a plastic jar, full of tap magic, and swipe the bit now and then), and I "peck" at the titanium until the hole is drilled. Works for me, but i'm betting there's better ways.

 

[jhiggins]

They usually won't last very long, but it can be done with HHS. I like using cobalt drills (screw machine type, much shorter, from places like MSC). I use a lube (I keep a acid brush in a plastic jar, full of tap magic, and swipe the bit now and then), and I "peck" at the titanium until the hole is drilled. Works for me, but i'm betting there's better ways.

The pecking method is good practice for any material, Robert. It serves to break the chips and clear the hole. HSS bits are fine for Ti, but like you say, they aren't the best choice. I suggest 118 degree cobalt, and carbides will of course last a good long time. But I must also say that I rarely sharpen a small bit. I usually only resharpen bits over 3/8", and I do that by eye. Most of the time I just give 'er the ol' toss and buy a package of new ones. With that philosophy, its not hard to understand the economics of buying a new bit vs resharpening an old one. Its a time saver for me. This is why I try to stick to 6AL4V Ti and use aircraft-grade cobalts when I can, but this is not to say that a good HSS heavy-duty bit wouldn't serve you just as well as long as you don;t get into anything tougher than 6AL4V.

 

[Tom Krein]

Jeff,
You really should look into purchasing a drill doctor. Cobalt bits and quality HSS bits are not cheap. You will also not be tempted to keep using a bit once it gets dull. The drill doctors are easy to use and not to expensive. If you still want to throw them away save em up and send them to me.

Tom

 

[jhiggins]

Jeff,
You really should look into purchasing a drill doctor. Cobalt bits and quality HSS bits are not cheap. You will also not be tempted to keep using a bit once it gets dull. The drill doctors are easy to use and not to expensive. If you still want to throw them away save em up and send them to me.

Tom

I have one, Tom. Its a pita to use. Over the years I've never found one that I liked, or actually provided a decent edge. I simply adapted to buying bits in quantity and saved money that way. If you are into pinching pennies, then a Darex or another type of sharpener may work well for you, but time is money and most production shops I've worked in hate to see an employee sharpening a bit unless its a big one. Usually what I do is toss the bad ones in a can and when I need a piece of pin for a jig or setup I go there. Thsi really isn't a bad practice. I say choose your battles. I'd rather scrimp on some other area. Heck, I know guys who use a fresh stencil with every knife and throw the old ones out with only one use. Each to his own.

 

[Sylvester]

As for a lube I would give Anchorlube G-771 a try.
Its designed for hard working metals, Like stainless
an exotic stuff. I`ve used it for years.

 

[L6steel]

I've found that speed is the key when drilling titanium.
I do all my folder drilling on my variable speed mill drill now and when I drill ti I run it real slow.
I agree with the pecking idea and use it to keep debris clear from the hole and bit.
It reduces heat which is the big enemy when drilling any metal but especially ti. Work hardening ti is a bear, especially when you have to go back through the holes with a precision ream.
There's my 2 1/2 cents.
Hope it helps some.