Drilling out a rusted screw
04-16-24, 10:29 AM
#26
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For that location, put it in a vise on top of a drill press table. Use a plunge cutting end mill to clean up the surface of the screw, then center drill then drill to tap drill size then tap. Using an endmill in a drill chuck is not ideal but in a pinch it can be done.
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04-18-24, 02:05 AM
#28
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Didn't read all the replies, but I'd use a Dremel & cutoff wheel to slot the bolt and then use a flat screwdriver tip (modified to be thin enough to fit within the braze-on hole) in an impact wrench to break it free. But before that, I'd also let penetrating oil time to soak in, utilize a heat gun and tap on it with a punch to try to break the chemical bonds free. And try to turn the bolt clockwise AND counterclockwise with increasing impact forces. Slotting with a Dremel may also slot the braze-on face, but who cares? More than enough material there for a rack bracket to sit against. I'd do all this prior to drilling out the bolt. Once you go down that path, there's no going back, whereas if you attempt the slotting method, you can resort to drilling if it doesn't work.
Or tack welding something to it. This would also be a last-resort method in my book as you'll fry off the paint.
Pretty sure you could re-drill and re-tap that braze-on for the next larger bolt, right? Maybe SAE could offer a smaller jump up in diameter?
Curious how it works out.
Or tack welding something to it. This would also be a last-resort method in my book as you'll fry off the paint.
Pretty sure you could re-drill and re-tap that braze-on for the next larger bolt, right? Maybe SAE could offer a smaller jump up in diameter?
Curious how it works out.
04-18-24, 05:51 AM
#29
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I have removed broken bolts for 15 years as part of my job. Something that has saved me many times on small bolts is pretty random, but some people already have them.
A vibrating engraver, like the link I'll post below. If you put that little carbide tip on the bolt and rattle it around, it'll probably spin out. You actually gave yourself a good little shelf to put the tip on with that hole you drilled at 11:00. Go both directions if it doesn't start spinning right away. And, if you have to order one of these, use the couple days waiting on shipping to soak that thing in Kroil, PB Blaster, or ATF/Acetone mix.
https://www.amazon.com/Electric-Vibr.../dp/B07W81V48C
A vibrating engraver, like the link I'll post below. If you put that little carbide tip on the bolt and rattle it around, it'll probably spin out. You actually gave yourself a good little shelf to put the tip on with that hole you drilled at 11:00. Go both directions if it doesn't start spinning right away. And, if you have to order one of these, use the couple days waiting on shipping to soak that thing in Kroil, PB Blaster, or ATF/Acetone mix.
https://www.amazon.com/Electric-Vibr.../dp/B07W81V48C
04-18-24, 06:08 AM
#30
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I have removed broken bolts for 15 years as part of my job. Something that has saved me many times on small bolts is pretty random, but some people already have them.
A vibrating engraver, like the link I'll post below. If you put that little carbide tip on the bolt and rattle it around, it'll probably spin out.
A vibrating engraver, like the link I'll post below. If you put that little carbide tip on the bolt and rattle it around, it'll probably spin out.
04-18-24, 08:21 AM
#31
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Exactly!
failing being able to rattle the screw out, they are pretty good at putting a center in the middle of the bolt so the drill bit doesn't walk when drilling, too. like the center punch idea, but without having to hold the frame still with one hand, the punch with one hand, and the hammer with your third hand... lol
failing being able to rattle the screw out, they are pretty good at putting a center in the middle of the bolt so the drill bit doesn't walk when drilling, too. like the center punch idea, but without having to hold the frame still with one hand, the punch with one hand, and the hammer with your third hand... lol
04-18-24, 09:23 AM
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04-18-24, 09:57 AM
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More of a metal working question I'd imagine but I installed a rear rack many years ago using carbon steel fasteners thinking I'd swap them for stainless in a timely fashion Needless to say I forgot all about them and they rusted in the threads of my aluminum Jamis Coda. One drilled out very easily essentially disintegrating without even using the easy out. On the other I've gone thru five drill bits and only managed to get a single 1/16" off center hole in the broken off flush threaded section of the screw. Really trying to not damage the thread in the frame so what are best practices for drilling out a machine screw ( now just a threaded stud ) from an aluminum bike frame?
Edit: My image loading skills were deficient
Edit: My image loading skills were deficient
I think your best bet now is to continue - carefully - drilling out the lower hole, soaking it with thread penetrant overnight, and hoping you can get the remainer of the bolt to break free and unscrew. You may have to install a thread replacement ( ++ TIME-SERT Metric Kits ++ thread repair kits and inserts repair stripped threads damaged threads repaired threads threaded inserts for metal thread inserts for metal aluminum inserts threaded inserts for aluminum (timesert.com) and go up to a 6mm machine screw.
04-18-24, 10:11 AM
#34
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Also keep an automatic centerpunch in your car for water based emergencies - much more efficient than one of those pointy hammers at breaking a window!
04-18-24, 10:30 AM
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They're too cheap to fix.
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An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
