HUGE flathead screws

[Figment]

What's the best way to proceed with screws that are larger than any commonly-found screwdriver?

For example.... Those monstrous flathead screws that secure the stemhead fitting.

[Tim]

I have several old hand-me-down screwdrivers that work for that sort of thing. Obviously that's not a help to you. I haven't really looked, but an online search didn't find the right thing either. I'd think that you might have to go to Snap-on or Mac or some professional outfit to find the proper large screwdriver. Sometimes the el-cheapo sets at your local discount auto store have a large screwdriver in them, but the blades tend to twist into nothingness when they're actually placed into a screw head.

Not much help, I guess!

[bcooke]

I wonder if it just might be quicker and easier to drill off the heads and then grab the stems with vise grips once the fitting is removed. New screws could be installed with a more normal sized screwdriver since the torque probably doesn't need to be very high. You could shop for a big screwdriver but I bet Snap-Off would want good money for a screwdriver you might only need once or twice in your life. They would most likely have to backorder it for you too. You never know though.

As you are carving the turkey tomorrow pay no attention to the little voice that says "... you know the back side of this carving knife would probably fit into that screw slot nicely..."

-Britton

[Tim]

I will typically buy any tool that I need for a project, no matter how obscure, if the price is under $50 or so (high end). I usually find that if I need it once, I'll need it again someday. In this manner does one slowly build up a tool inventory of some importance.

I've found enough uses for my old "ancestor" screwdrivers that I'm sure I would have bought one otherwise.

Obviously each situation is different, so choose accordingly.

I was thinking that a bastard file might me made to fit those screw slots, as one alternative.

[Figment]

I will typically buy any tool that I need for a project... In this manner does one slowly build up a tool inventory of some importance.

I find that I often make any tool that I need for a project. In this manner I've slowly built up a tool inventory of some completely ridiculous objects.
A scratch awl, heated and corkscrew twisted, for capturing the self-adjuster spring while working on drum brakes.
A kabob skewer with the end flattened and hooked three different ways, for feeding wires into tight places.
A vise-grip welded to a length of 1" iron pipe, for when you need to affix a breaker bar in juuuuust that position.

The list goes on and on. I'll probably wind up fashioning something out of a scrap of bar stock, and try to figure a way to chuck it into my brace.

[Curmudgeon]

Just a thought, but I recently bought a set of impact bits and it included a honking-big slot bit. Those bits can be used in a regular socket set, or even with a wrench - the socket and driver would give you a better purchase tho'. In fact, if the screws are posing a real problem to remove, a complete impact kit would be a perfect choice, and as Tim said "If you need it once..." The screws holding my steering pedestal weren't budging until I tried the impact wrench. then I went four-for-four removing them.

I would be disinclined to drill the heads off the screws until I ran out of other options - they'll destroy themselves in short enough order without much help, then you can go to Plan B.

[kaynee30]

I used a screwdriver I inherited from my grand dad...from the thirties. I've seen a few like this in antique places and flea markets.....they seemed to have been a much needed thing once. A couple bucks. Some kind of super-duper steel , too. Can't kill it.
I never did get the stemhead fitting off. I worked around it.
Jeff

[JetStream]

I found that the impact sets include a pretty big driver bit that you can also chuck into a Stanley brace. Sometimes, the really big bits are available at antique tool sales, but I've never seen them sold in new tool houses (and I looked.) The boat yard guys used to have the drivers to chuck into a brace, and thats how the screws were driven in the first place.

[Robert The Gray]

grind down an inexpensive cold chisel? Keeping the metal cool to not lose the temper
Just a guess, they usually have a hexagonal section.

[Dan]

I was thinking that grinding an Allen wrench might do the trick. You could get some good leverage as well.

[Figment]

And the winner is........

A spade bit. I ground down a mostly-ruined-anyway spade bit and chucked it into my brace.

I tried the mill file idea first, but it couldn't take the torque. Shattered like glass.