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Do you have a "go to" bit you like to use to drill out old screws? Is it carbide-tipped? Do you use a Dremel or drill?
thanks.
 

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I do use a dremel tool to get either a nice flat top to drill into or slightly cupped if the fastener is larger. If there is plenty sticking out, I use the dremel to cut a slot first and try and back it out with a screw driver. If the fastener is seized, I skip that and go right to one of my Snap-on left handed drill bits. Usually, just the drilling action spins the fastener out without even having to use an easy out.

After drilling out about a half dozen bolts in an old Honda outboard, I was chatting with an old time mechanic and he told me if you coat the stainless bolts with Permatex #2 before you screw them into the aluminum, you'll never break off another bolt. I tried it and it worked. I was using the "Never Seize" type coating prior to that, but now if I'm screwing into aluminum, I use brown goopy/sticky permatex. Oh and if you get some of that on your fingers, alcohol cuts it.
 

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If you are drilling them out to use a screw extractor, use a drill with a good quality bit (not carbon). If you are just grinding off the head use a Dremel.
 

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I have had trouble finding #2 Permatex. I used it for sealing split cases on outboard and motorcycle engines years ago. I used to keep a half pint bottle of the stuff thinned with alcohol. I would just paint it on with an acid brush, then put it together. This worked much better than the 3M Weather strip cement others were using as it did not glue things together, it just sealed them.

I am not sure about using it with our modern alcohol polluted fuels though.

Have FUN!
O'
 

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Do you have a "go to" bit you like to use to drill out old screws? Is it carbide-tipped? Do you use a Dremel or drill?
thanks.
First try getting it out with an impact hammer. That can often break out the corrosion.

A left handed drill bit along with a bolt extractor bit works very well.

If you are drilling into stainless screws then you want carbide bits. You also want a slower drilling speed with lots of pressure. If you aren't making a chip with every turn of the bit then you are work hardening the stainless and will dull your drill bit.
 

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First try getting it out with an impact hammer. That can often break out the corrosion.

A left handed drill bit along with a bolt extractor bit works very well.

If you are drilling into stainless screws then you want carbide bits. You also want a slower drilling speed with lots of pressure. If you aren't making a chip with every turn of the bit then you are work hardening the stainless and will dull your drill bit.

I think you meant COBALT bits which work very well for drilling SS.

BTDTGTTS
 

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I tried everything several times in a row for drilling out a few bits and never had any luck until someone showed me the right technique.

Basically, start with with a small bit, like 1/8 and drill SLOWLY with the bit with a lot of pressure on the drill. It should start to carve into the head with a small streak of shavings coming off. Go as deep as you want, then move to the next size up, which should carve the sides out of the 1/8 hole you just made. Progressively work your way up until you can punch it out. The key is to start small, go slow, and keep it from heating up (I usually cool it with WD-40).

It takes patience, it's less drilling and more carving.
 
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