At 09:53 PM 3/7/00 -0000, Graham Stretch wrote:
>
>Hi Jeff
>Whilst we're on the subject of taps here's a tip, and possibly the reason
>your tap broke, always ensure that none of the original bolt is left in the
>hole you are going to re-tap, if some is left as you tap the thread the
>piece of old bolt will often come loose and act as a wedge, (it gets pulled
>round rather than have a new thread cut in it!) jamming the tap solid. I am
>a toolmaker and spend a good proportion of my time repairing steel dies for
>casting aluminium, these take a pounding and often screws holding the
>handles etc break. I have been where you were several times and have found
>this to be a big cause of broken taps, of course they will also break all of
>their own accord! I hope this can ease your troubles in future.
Just to inject 2 more cents, when using a tap, tie, or trying to remove
a difficult nut or bolt, DON'T try to do it all at once. When it is tough
to turn, only take about 1/2 turn, then turn it back. This helps break up
the crud that is either being cut by the tap/die, or helps loosen the rust.
Once things are going a little easier, you can go about a full turn or so.
If you don't, you'll break the tap, or bolt.
John
John T. Blair WA4OHZ email: jblair@exis.net
Va. Beach, Va Phone: (757) 495-8229
48 TR1800 48 #4 Midget 65 Morgan 4/4 Series V
75 Bricklin SV1 77 Spitfire 71 Saab Sonett III
Morgan: www.team.net/www/morgan
Bricklin: www.bricklin.org
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