On Fri, 10 Jun 2005 21:31:38 +0200, Bob & Linda Gardner
<
gardner.bob@...> wrote:
> Stefan,
> For a drill bit size chart try:
> <http://drillbitcity.com/images/charts/drill_bit_comp_chart.pdf>
> Bob
Thanks, that's what i needed. Thanks als for the other offers.
As for moving the rings, i will still try a hammer, because i'm pigheaded
;-)
When i have broken a bit i will perhaps make a jig that can be used in a
vice or something. I only see how to move the ring in one way, anyway, i
gueess one must start all over if one moved it too far.
Thinking about it, a simple mechanism with a screw would be easy to make.
take a piece of tubing, just bigger than the ring, and either cut a
screwthread inside it or braze a nut to it. on the other end mount a
washer that has a inner diameter smaller than the plastic ring outer
diameter. you slip the tubing piece over the bit from the front, so that
the washer sits against the ring, and then simply screw the screw in to
pull the ring back on the shaft, the screw pressing against the end of the
drill. should allow precise adjustment, just add wings to screw and tube
for easy turning by hand. theoretically one might be able to drill out the
screw to allow pressure from the other side also, but probably it would
cause beaking of the drill if all is not straight. Probably it is easier
to make two screwsm one with a flat or slightly depressed end to normally
push the shaft along, and one with a stud slightly smaller than a drill
shaft, to press the ring all the way off (of one has moved it too far or
it must go on another bit).
Varitions to this design could be contemplated, like allowing to insert
the drill from the side so it isn't necessary to take the tool apart
completely, but it would be more difficult to make.
Now i wonder what professional bit grinding shops or manufacturers use?
ST