Any ideas on how to remove this set screw? The head broke off and I can't get a drill bit that will drill into the set screw. I need to remove the coupling to change a seal. Any suggestions would be appreciated. Thank you!
Removal of set screw
- Thread starter FlimFlamII
- Start date
You could try this:
http://www.amazon.com/DRILL-MASTER-...62&sr=1-1&keywords=drill+master+screw+remover
I bought my set at Harbor Freight. They are like left handed hardened drill bits with an e-z out built in. The problem may be that your original screw might have been siezed. Use plenty of PB blaster first and maybe even heat the surrounding area with a mini torch to expand the hole. If you try and drill it out with a regular bit, don't push hard. You risk breaking the drill bit off and then you will probably never get that hardened material out. After removing the coupling, consider a split coupling from PYI so you won't have that problem again. Good Luck.
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I tried to use an e-z out but I cannot get it to bite into the screw head. I tried drilling a pilot hole and the bit would not even dent the set screw... Any ideas?
Thank you!
Thank you!
When you say "the head broke off" I think you mean that this fastener was a machine bolt as opposed to a set screw. In any event it looks like you have a small amount of screw material above the surface of the flange. I would use a file or a Dremel tool to smooth the top of the broken bolt so it is flat. Then as Woody suggests, center punch the screw. Make sure you are using a hardened center punch that will actually dent the screw. If the screw is stainless, you need a center punch that will be harder than the screw.
Then you need to buy a high quality drill bit that is rated to drill stainless. I would buy a couple drills from 1/16" to just under the size of the broken bolt. Drill slowly with one of the smaller drills. If you have cutting oil use it, otherwise substitute another light oil. After you get a small drill 1/8" or more into the broken stud, go up a size in the drill.
After you get a fairly good hole in the stud you have a choice. You can try an easy-out or if there is just a shell of the broken stud left you can run a tap of the thread size into it and clean out the remaining bits of the broken stud. If you don't know the thread size then a tap is not an option.
Use a liberal amount of PB Blaster for a couple days before you start any of this.
Then you need to buy a high quality drill bit that is rated to drill stainless. I would buy a couple drills from 1/16" to just under the size of the broken bolt. Drill slowly with one of the smaller drills. If you have cutting oil use it, otherwise substitute another light oil. After you get a small drill 1/8" or more into the broken stud, go up a size in the drill.
After you get a fairly good hole in the stud you have a choice. You can try an easy-out or if there is just a shell of the broken stud left you can run a tap of the thread size into it and clean out the remaining bits of the broken stud. If you don't know the thread size then a tap is not an option.
Use a liberal amount of PB Blaster for a couple days before you start any of this.
Yes, what the Woodster says. But also the drillmaster tools have very robust drill tips that you can push on. They should bite and the e-z out portion has a different taper and many more serrations to bite. Make sure you use the lowest speed and highest torque on the drill. If you go fast the screw will work harden and it won't drill. Also the extracter part will twist out rather than grab.
I was going to suggest the left handed drill bits too. Had pretty good results with them. I got mine at Harbor Freight
If all else fails, using new, rated for SS bits, drill a hole the length of the setscrew, move to the next larger size and repeat, repeat till you are very close to the threads on one side (the drill hole will be off center by this time), then take a small drift punch or nail with the tip ground flat and cave in the thinnest section of the set screw, futz with is till you get the rest out. Don't forget to use neverseize when you reinstall the new setscrew
Good luck
Good luck
Had to resort to grinding it out with a Drexel. The space was so confining I couldn't even get a good position to center punch for drilling. I thought the shaft was keyed but it turned out the screw was threaded into the shaft... I now plan to drill a new hole on the opposite side. Figure this way I can salvage the coupling.
No key? I wonder if things rotated a little causing the screw to bend enough to keep it from turning when trying to remove. I hope it doesn't happen again. It sounds like there was only one set screw? I still like my split coupling but it will set you back close to $200. No key is required on small engines. Very high clamping force.
Thanks for sharing.
Thanks for sharing.
Had the same situation a few years back - the square head snapped off flush with the coupling. Ruined that quick job...
The key to drilling hard material is a good bit (cobalt) and use lots of pressure. For creating the pressure I use a jorgan (S&P?) clamp. The stationary jaw is put on the opposite side of the coupling and the screw handle / clamp on the back of the drill. I always grind a flat spot on the back of my drills to allow the clamp to sit better. I've used this method to drill out bolts, drill holes in stainless and other metals in awkward places. Keep a lot of pressure on the bit by screwing the clamp handle down and it will cut like "butter"!
The key to drilling hard material is a good bit (cobalt) and use lots of pressure. For creating the pressure I use a jorgan (S&P?) clamp. The stationary jaw is put on the opposite side of the coupling and the screw handle / clamp on the back of the drill. I always grind a flat spot on the back of my drills to allow the clamp to sit better. I've used this method to drill out bolts, drill holes in stainless and other metals in awkward places. Keep a lot of pressure on the bit by screwing the clamp handle down and it will cut like "butter"!
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On the new bolt you could use some anti seize. Use safety wire and you won`t have to tighten the new bolt as much.