My Harbor Freight titanium coated drill bits aren't cutting it. In fact, they fail miserably whenever I try to drill through any type of steel. I need a set of drill bits that will drill through SS and other tough metals. I have been looking at the Drill Hog sets that have the split point, in molybdenum and cobalt.
What are the main differences between the molybdenum and cobalt drill bits and which would you get?
l told my pap and mam I was going to be a mountain man; acted like they was gut-shot. Make your life go here. Here's where the peoples is. Mother Gue, I says, the Rocky Mountains is the marrow of the world, and by God, I was right. - Del Gue
But whatever you get, stainless steel is the enemy of drill bits.
Run it slow and keep everything saturated with dark thread cutting oil. Most types of stainless will work harden in a heartbeat. Once that happens you're going to have trouble getting through it.
Good quality high speed steel or Tungsten Carbide are the only drills worth buying for serious drilling of anything tougher than mild steel. Try shopping with Victor Machinery Company. www.victornet.com I've been buying drills, milling cutters, and other tooling from them for several years. Their prices are reasonable, and they have several different choices of drill bits available, including some very high quality USA-made stuff.
The trick to drilling tough metal is to use the right speed, feed rate, and lubricant. Once a drill starts to "skate" without producing chips, it dulls quickly. Jerry
Hotrod: Are you recommending high speed bits that are cobalt? What brand set do you recommend - the Drill Hog sets have a lifetime warranty, for whatever that's worth.
l told my pap and mam I was going to be a mountain man; acted like they was gut-shot. Make your life go here. Here's where the peoples is. Mother Gue, I says, the Rocky Mountains is the marrow of the world, and by God, I was right. - Del Gue
l told my pap and mam I was going to be a mountain man; acted like they was gut-shot. Make your life go here. Here's where the peoples is. Mother Gue, I says, the Rocky Mountains is the marrow of the world, and by God, I was right. - Del Gue
Slow down drilling. More pressure is better. Use a water soluble oil. Cutting oil doesn’t cool like the water does. Heat is your enemy. Cobalt drills are maybe 3 points harder on RC than regular HSS. Worth it. The titanium nitrate coating only helps if you have a good steel under it. You can coat carbon steel. 135 with a split point. 135 deg is less tool interface. Split point takes less tool pressure. Run a fine stone across the the cutting edge. Crates works best. Sandpaper is fine. So it’s smooth when you run your finger along it. That very sharp edge breaks down quicker. And then you are dull. The stoned edge is much tougher. I’ll drill thru 4’ of parts of 410 or 316 SS without having to sharpen the drill. 2” drill. Regular HSS not cobalt.
I’m too lazy not to do it right. Some guys will go and hand sharpen 5-7 times for the same job.
Any other questions. Just ask. And slowdown and keep the pressure up.
You're just paying extra for the name when you buy Drill Hog- - - - -sort of like buying a gussied-up Suburban and calling it an Escalade. Stick with US-made Cobalt alloy drills and forget paying the premium for the name brand stuff. Most jobber-type drills come with a 110 degree angle to the cutting flutes. If you sharpen your own bits, flatten the angle a little and use a drill press with lots of speed reduction and plenty of down pressure. With a slow enough speed and lots of downforce, I can drill a hole in a spring leaf. For the really tough stuff, use a solid carbide bit, but remember that stuff shatters like glass with the slightest bit of side load. Jerry
My Harbor Freight titanium coated drill bits aren't cutting it. In fact, they fail miserably whenever I try to drill through any type of steel. I need a set of drill bits that will drill through SS and other tough metals. I have been looking at the Drill Hog sets that have the split point, in molybdenum and cobalt.
What are the main differences between the molybdenum and cobalt drill bits and which would you get?
Stovepipe AKA Marginless is what you want for Stainless.
Hotrod: I found 21 piece Drill Hog sets in both cobalt and molybdenum for $47.00 $37.00 respectively. I haven't been able to find US-made Cobalt sets for any less than ~ $87.00. The Drill Hog sets seems a much better value - am I overlooking something?
l told my pap and mam I was going to be a mountain man; acted like they was gut-shot. Make your life go here. Here's where the peoples is. Mother Gue, I says, the Rocky Mountains is the marrow of the world, and by God, I was right. - Del Gue
Victor part number DSCO 29- - - - -29 piece Cobalt, 1/16"-1/2" for $65.00. Maybe the Drill Hog sets are on sale? I buy drills individually, not in sets, and I keep several of the sizes I use a lot on hand. That way, when one gets dull, I can swap to a sharp one and keep on working, then resharpen a bunch of them at one time. I've usually got a dozen or so of the common sizes ready to go.
l told my pap and mam I was going to be a mountain man; acted like they was gut-shot. Make your life go here. Here's where the peoples is. Mother Gue, I says, the Rocky Mountains is the marrow of the world, and by God, I was right. - Del Gue
Titanium nitride coating is just a way to get a couple of good holes drilled with a piece of crap soft Chinese drill bit. Once the coating wears away, most of the drill bits sold by Harbor Freight have a hard time cutting soft butter. Resharpening doesn't help if the metal underneath the plating is too soft to hold an edge. I mix up a spritz bottle of water and soluble cutting oil and mist the solution onto the drill bit to keep it cool and also lubricate the cutting flutes. Jerry
