Stripped Scope Mount screws

[Aldon]

Thanks Chad.

Perhaps this thread will come in handy for someone else in the future.

I appreciate your input.

Aldon

 

[Mike6158]

Sounds like all's well that ends well but this thread reminded me of something and I thought it might be a good place to ask the question. About 20 years ago ( time flies) a company that I worked for had problems with compressor cylinders falling off ( I was able to convince them to redo the foundations and anchor the outboard end of the cylinder and the problem went away). The bore's on the cylinders ranged from 8" up to 22" and horsepower was around 1,000 after derating for altitude. In the compressor world that's not so big but I digress. One solution that they used as a preventative measure (that only served to delay the inevitable) was to increase the bolt size from 1-1/16" to 1-1/4" and they would still snap the heads off (I'm no engineer but ****... some things aren't rocket science). Not wanting to remove the entire cylinder and back out the bolt stub (downtime was big deal to us) they (we) bought a drill with a magnetic base (big sucker) and left turning drill bits. Most of the time the bolt would back out during the drilling process.

I have always thought that a set of smaller left turning drill bits, say 1/8" or even 1/16" through 1/2" would be handy to have for screw extraction but I have never been able to find them. Anyone know where I could find these?

 

[jimbires]

Sounds like all's well that ends well but this thread reminded me of something and I thought it might be a good place to ask the question. About 20 years ago ( time flies) a company that I worked for had problems with compressor cylinders falling off ( I was able to convince them to redo the foundations and anchor the outboard end of the cylinder and the problem went away). The bore's on the cylinders ranged from 8" up to 22" and horsepower was around 1,000 after derating for altitude. In the compressor world that's not so big but I digress. One solution that they used as a preventative measure (that only served to delay the inevitable) was to increase the bolt size from 1-1/16" to 1-1/4" and they would still snap the heads off (I'm no engineer but ****... some things aren't rocket science). Not wanting to remove the entire cylinder and back out the bolt stub (downtime was big deal to us) they (we) bought a drill with a magnetic base (big sucker) and left turning drill bits. Most of the time the bolt would back out during the drilling process.

I have always thought that a set of smaller left turning drill bits, say 1/8" or even 1/16" through 1/2" would be handy to have for screw extraction but I have never been able to find them. Anyone know where I could find these?

Mac tools did sell a set of lefty drill bits . I bought a set of them years ago .I think the set I have is 1/16 -3/8 . I have had about 25 % success of removing broken bolts by using these bits alone , without the help of an easy out . Jim

they still have them . here is a link .
Mac Tools -> Search Results

 

[Mike6158]

Well that's just cool as can be. Thanks Jim. I've been looking off and on for those things for years.

Now they are everywhere I search There's a larger set of Irwin left hand bits here