I had kept this from a few years back, a post about making your own, I believe the pertinent information is from tw. BTW, tw, if you see this can you explain the last bit about grinding to prevent "camming out"?
... not sure how to exactly go about the annealing and then hardening. Care to elaborate?
sure. however the REAL mechanics here are probably going to have apoplexy.
i start a pot of tea-water to boiling and stick the tips of some number of screwsticks in the flames of the kitchen gas stove. they get good&red about the time the water is hot. shove the screwdriver tip-down into a bucket of woodash or vermaculite and forget about them for a day or two. then i sort them by size without being particular about greasing or rust prevention.
when you need one, find the about-closest-fit one. brush&polish all the rust & crap off the tip and up the shaft a ways, then grind & file to your exact need. don't forget to radius-grind the blade 1⁄4" or so to make sure the flats are parallel.
play the blade and an inch or two of the shaft in a propane or mapp torch until red-red and quench in whatever liquid is handy.
to temper, turn off most of the light in your shop - dimmer is better than either light or dark. place the screwdriver *shaft* about an inch up from the blade in a steady propane/mapp flame. almost inststantly, bands of colors will start marching both ways away from the from the heat point. when the dividing line between blue & straw gets close to the tip, quench.
and you're good-to-go.
literally, from the time you finish grinding, filing and fitting, it takes longer to type this up than it does to harden & temper.
when you are finished with the screwdriver, put it in the basket: 'too be annealed'.
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Posts: 6 | From: texas | Registered: Dec 2004 | IP: Logged |
Chuck H
Sidelock
Member # 3831
Member Rated:
posted January 14, 2005 09:18 PM
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Lime will work if woodash or other is not available for annealing.
Only caution I'd say would be some of the really cheesy import (Chinese) screwdrivers may not have enough carbon to harden.
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Posts: 1847 | From: Torrance, CA | Registered: Feb 2004 | IP: Logged |
Recoil Rob
Sidelock
Member # 80
Rate Member posted January 14, 2005 11:32 PM
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Any problem with the blades loosening up in the plastic handles from the heat?
Thanks, Rob
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Posts: 837 | From: Vista, NY | Registered: Jan 2002 | IP: Logged |
tw
Boxlock
Member # 3297
posted January 15, 2005 11:51 AM
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FWIW, if there are no garage sales nearby just go to the closest pawn shop. I have bought them by the handfull for two bits($0.25) apiece for years. Have used similar method explained above, no tea pot for anealing/hardening, when necessary, but frequently use fine grit tool post wheel followed by a quick quench in oil.
For a parallel slot the screwdriver tip will not cam out if you radius the sides looking at the tip face on, so that the sides look like this ..( )
Kind regards, tw
