Why aren't 118⁰ split point drills a thing?

Batmanacw

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I sometimes split the points on my 118⁰ drill bits. Why isn't that a thing? They seem to walk less and make a nice hole.

It has always seemed that 118⁰ drills produce rounder holes. Why no 118⁰ split points?
 
I sometimes split the points on my 118⁰ drill bits. Why isn't that a thing? They seem to walk less and make a nice hole.

It has always seemed that 118⁰ drills produce rounder holes. Why no 118⁰ split points?

I've never had trouble finding split point drill bits in 118 degrees. I split my own (3/16 and up) and I rarely buy ones that are not factory split point. (But I have, and will again). I rarely use the split point (There's always exceptions, but I aim to pilot just bigger than the chisel point, even if it has been split). The times that I do want the split point, it's priceless.

If the store you're at doesn't have them, that might be the issue right there. There's a thousand other things that are a bigger factor, but splitting the point is an extra cost.

One very valid reason to avoid factory split points and split them yourself is if you're using a drill sharpener. Some sharpeners have a problem with that. (not all, some, including Drill Doctor, which is pretty popular), The most common way of grinding the factory split point leaves a huge gouge in the back side (unused side) of the flutes, right where a lot of sharpeners index to. That could, depending on your sharpening method, be a big deterrent to buying split points new.
 
One very valid reason to avoid factory split points and split them yourself is if you're using a drill sharpener. Some sharpeners have a problem with that. (not all, some, including Drill Doctor, which is pretty popular), The most common way of grinding the factory split point leaves a huge gouge in the back side (unused side) of the flutes, right where a lot of sharpeners index to. That could, depending on your sharpening method, be a big deterrent to buying split points new.

I have a love/hate relationship with my Drill Doctor. I think you just solved it. Thank You.
 
Sharpen them yourself. I used a drill jig I made for this one, mostly,though I sharpen by hand, using a combination of conical and facet grinding.. I use facet points because conical grinding gives a chisel point, no walking with facet grinds..
 

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A little off subject but I have a question. I am a mechanic by trade and I work on a ton of diesels and therefor see my fair share of broken off stainless bolts in various sizes too. Question is what would be you guys go to drill bit for this kind of work? Material, degree and anything else you could add. Also do muy fair share of exhaust manifold bolts where drilling dead center is an absolute must
 
A little off subject but I have a question. I am a mechanic by trade and I work on a ton of diesels and therefor see my fair share of broken off stainless bolts in various sizes too. Question is what would be you guys go to drill bit for this kind of work? Material, degree and anything else you could add. Also do muy fair share of exhaust manifold bolts where drilling dead center is an absolute must
I like to start out with a much smaller stubby drill bit to create a divot, but I'll angle the drill to move the divot to the center of the bolt before drilling. I haven't worried much about the cutting edge angle but a 135⁰ split point would cut a bit freer in stainless.

I don't usually use anything special for that sort of work.
 
I like to start out with a much smaller stubby drill bit to create a divot, but I'll angle the drill to move the divot to the center of the bolt before drilling. I haven't worried much about the cutting edge angle but a 135⁰ split point would cut a bit freer in stainless.

I don't usually use anything special for that sort of work.
That’s one trick I have learned over the years is tilting to bit to center up on the bolt. I personally have found a good cobalt bit to work the best. I just wasn’t sure if there was anything out there better. I have just purchased some new 3 flute drill bits but have not tried those
 
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