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Posted by BobK207 on July 4, 2007, 1:23 pm
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> >> > > On Jun 23, 8:22 am, trad...@optonline.net wrote:
> >> > >> On Jun 22, 10:45 pm, t...@mucks.net wrote:
>
> >> > >> > On Fri, 22 Jun 2007 23:41:30 -0400, t...@mucks.net wrote:
> >> > >> > >It is most important that keep the drill centered. Guide the
> >> > >> > >drill at
> >> > >> > >an angle until you get hole in the right location and then slowly
> >> > >> > >straighten the drill. Do not break the drill. Drill the screw all
> >> > >> > >the
> >> > >> > >way through.
>
> >> > >> > >If you think loctite may have been used then heat the area until
> >> > >> > >smoke
> >> > >> > >shows the loctite burning.
>
> >> > >> > >When cool insert the extractor and tap downward to make the tool
> >> > >> > >grab.
> >> > >> > >This should remove it if you kept the drill centered.
>
> >> > >> > >If not drill the hole through with a root diameter drill as long
> >> > >> > >as
> >> > >> > >you can keep it centered. If you can Re-Tap.
>
> >> > >> > >If this still fails then purchase a thread insert and follow the
> >> > >> > >directions.
>
> >> > >> > Best thread insert : Gardserts
>
> >> > >> >http://www.gardspecialists.com/-Hidequotedtext-
>
> >> > >> > - Show quoted text -
>
> >> > >> I've can't imagine how you could use a screw extractor on a 10-32
> >> > >> screw to begin with. I've never seen one that's small enough to be
> >> > >> used on a screw that small.
>
> >> > > I've used screw extractors on screws as small as #6's.....but its
> >> > > usually a 50-50 success rate even on the bigger ones.
>
> >> > > IMO you need good quality extractors...I have a set of Hanson's that
> >> > > has extractors for even smaller screws.
>
> >> > >http://www.mytoolstore.com/hanson/extractr.html
>
> >> > > The trick is to drill down the centerline of the screw, drill the
> >> > > right size hole......too big & the screw extractor tends to expand
> >> > > the
> >> > > screw & lock in the hole....too small & you won't get a good bite on
> >> > > the screw
>
> >> > > a brass screw is pretty soft so the extractor might chew it up rather
> >> > > than bite & extract.
>
> >> > > MC, if you've got through hole you might be able to drill with
> >> > > successively bigger drill until on the threads of the screw are left
> >> > > &
> >> > > then you can pick at the screw & maybe unwind the thread.
>
> >> > > If the hole's not too badly messed up you might be able to chase the
> >> > > threads & re-use the hole as is...otherwise bump up to the next size
> >> > > (#12) or do a hole repair with a Heli-coil
>
> >> > > cheers
> >> > > Bob
>
> >> > Thanks Bob. I have drilled it all the way through and inserted the
> >> > screw
> >> > extractor and no good it won't bite. I then took a dremel with a cut
> >> > off
> >> > wheel to cut a deeper slot and tried again - it turned ... but bad
> >> > news, the
> >> > screw head came off and the rest of the screw is still inside the hole
> >> > and
> >> > none of it is protruding from the hole for me to get with a plier.
>
> >> > So now I have a short screw inside the hole, I guess I need to use a
> >> > bigger
> >> > drill bit but I think more than likely I will damage the thread of the
> >> > hole
> >> > since I don't trust myself to be able to drill totally straight and
> >> > centered. I have about 7 screws that are refusing to be extracted out
> >> > of
> >> > 16.
>
> >> > MC
>
> >> Did you read my earlier post? I know from years doing mechanical work
> >> that stubborn screws can be easily removed with an IMPACT DRIVER (not
> >> an air impact wrench). This is a simple tool that works with another
> >> simple tool, a hammer. Nearly 99% of professional mechanics will have
> >> one in their toolbox, but the general public and every one of your
> >> post responders seems to be blissfully unaware of this essential and
> >> low cost device. For under $10 you can likely solve your problem, $15
> >> if you need a hammer, and if it doesn't work due to corrosion or some
> >> other mechanical mishap you can then do a drill out and Helicoil
> >> routine knowing that the situation was hopeless to begin with. Good
> >> luck.
>
> >> Joe
>
> > Joe-
>
> > Just because some of us didn't suggest an impact driver doesn't mean
> > we don't know of their existence or their usefulness. .... I have one
> > but don't think it is the solution in this situation. Of couse I'm
> > not standing next to the screws in question..
>
> > Brass screw, 10-32
>
> > IMO doesn't seem like a good candidate for the impact driver
> > treatment.....................
>
> > MC-
>
> > Failing screw extraction I'd opt for successive drilling...if the hole
> > material is steel, it will tend to keep the drill drilling in the
> > brass (softer material) You can drill up close to the screw minor
> > diameter & then "pick" the remaining thread out.
>
> > Even a damaged threaded hole has some decent holding ability..... a
> > 10-32 brass screw needs only about four good threads if the hole is
> > steel, 6 threads if the hole is brass.
>
> > A 1/2" of thread (16 threads) for a 10-32 is a bit much.....you could
> > have a fair amount of those threads damaged & still secure a brass
> > screw
>
> > cheers
> > Bob
>
> Bob thank you very much for this advise. I finally tried what you suggested
> to drill it successively with larger sizes. I was prepared to completely
> ruining the thread. I tried one smaller size drill bit and drilled all the
> way through, then inserted a replacement screw, it actually went into the
> thread and turned one revolution! So I tried a bigger drill bit and drilled
> again, slowly and steadily, and afterwards I tried the screw again and it
> went in, with slight resistance but the threads are fine! I have to pick
> out the pile of metal collected at the bottom of the hole but the original
> threads are still good. Thanks again!
>
> MC
MC-
Thanks for the followup......I've messed up & fixed a fair number of
threads / stuck screws.
I think the reason the successive drilling worked out is that the
brass is so soft but that's also why the extractor didn't work.
A steel screw would have been more difficutl to drive but the
extractor would have bit (in a steel screw) rather than slipped as in
the brass screw.
To remove the debris you might consider a shop vac rigged up with a
small probe.
cheers
Bob
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