making inserted screwdriver bits

TRX

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I've run into a problem with what I thought was a simple task. I keep needing to grind down flathead screwdriver bits to fit weirdball screws. I've bought extras, but they're generally not very good, ranging in hardness from "soft" to "twists like a swizzle stick" when trying to break stuck screws free.

"So!" I think, "I'll just order a piece of 5/16" 4130 or 4140 hex stock and make a my own out of properly heat-treated steel."

How foolish...

So far, I haven't been able to find any hex stock smaller than 3/8", much less 4130 or even 1144. The best I've been able to come up with was to buy hex keys and cut them up, but many of those are soft too.

I could buy round stock and cut flats, but that seems like a ridiculous amount of work just to make screwdriver bits. So I figured maybe I was too close to the problem, and I'd give you guys a chance to laugh at my failure to come up with a simple solution.

What's the simplest way to make some screwdriver bits out of a decent alloy?
 
I feel your pain not foolish, just keep grinding like we all do. Maybe heat em up and throw em in a bucket of oil..
Oh those blastard Phillips always grinding those.....lol
 
To save on the work involved there are some good sets of gunsmith bits that are mostly different sizes of flat bits (with little or no other style bits like Robertson, Philips, Torx, etc.)

To grind my own for a special size I would start with the best quality Torx or hex (Allen) wrench and grind a flat of the right size but only just deep enough to fit the slot in the screw. No taper to the shank. Fine tune the fit with a hand stone.
 
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Yeah, I've been buying sets of the gunsmith bits, but most of them still require grinding. They seem to all be plain carbon steel, and I wind up twisting or breaking most of them, no matter what brand name is on the box.

I *could* just buy a length of round rod and make full-size screwdrivers, but they take a lot more space.

I have a modest collection of reground Craftsman and Snap-On screwdrivers, but even the Snap-Ons seem to be pretty soft nowadays, and I can't afford to pay Snap-On prices for something I have to modify anyway.
 
Brownells sells bits for gunsmiths that will break before bending. They sell the handles in magnetic and clip retention types. I have a large collection. As they break ,I regrind them to other purposes. The bits are hard thru and thru. Not case hardened. I also see driver bits in local stored (hardware and auto supply types) sold as individual pieces. Some are rather long and that would give you extra material to grind.
 
Brownell's also will replace free any screwdriver bit you break. I don't know if that includes free shipping. I will only use an exact width bit on my nice guns,and have a decent Brownell's set.

I must be lucky,because I haven't had any defective insert bits yet from anyone.
 
Ummm....just one thing to consider.....are you sure you want 5/16" and not 1/4" hex steel for your bits ? 99.9% of the ones we get here in Canada are 1/4" drive.......or did I miss something, which is entirely possible. :)
 
With 5/16 bits you could use one of these. Can't beat it for getting 'stuck' screws unstuck. The heavier the hammer the better.

Impact driver 002.JPG
 
Try the Milwaukee Shockwave Impact Duty Driver Bits. But when you grind the bitts you are removing the hardend serface.
 
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