| Author | Message | ||
     Rokoneer |
Picture a broken off stainless steel bolt in an aluminum frame. The bolt is broken flush with the surface that surrounds it. The drilling out of the bolt has succeeded with the first two drill bits used, but the third drill bit being used to enlarge the hole in the broken off bolt has broken off in the hole being drilled just below the top surface of the broken off bolt. So there is a broken off bolt with a broken off drill bit in it. Lucky me. I recall hearing from someone that you could mix alum powder into a paste or fluid and put it on or in the cavity where the broken bolt and drill bit are and over the course of a few days it will soften the steel tremendously while having no effect on the surrounding aluminum. Anyone else ever hear this, or something like it, or am I recalling things way off base....... | ||
| Gentleman_jon |
I would be very surprised to find such a "magic power". Steel can't be softened except by heat treatment, not very practical in this case. You got yourself a real problem there, I know some of our members who are more accomplished mechanics than my self will have their own, and effective tricks . Personally, I think I would put some Liquid Wrench penetrant on the threads, let it sit over night. Then get a stainless nut of the size that would fit on the bolt. Weld the nut to the remains of the bolt, let cool, and then remove the remaining stud. Any other ideas? (Message edited by gentleman_jon on March 22, 2005) | ||
| Wyckedflesh |
A picture of the situation might help. Try and find some reverse cut drill bits also, that way as the bit cuts in it puts directional tension with the threads instead of against, this can sometimes back the bolt out as your trying to drill. | ||
| Reepicheep |
carbide drill bits, or diamond tipped dremel tools will (with enough time, patience, and spares) go through the broken off drill bit, and you can pick up where you left off. | ||
| Spiderman |
Get these from sears. http://www.sears.com/sr/javasr/product.do?vertical=TOOL&pid=00953153000&bidsite= &BV_UseBVCookie=Yes  They work great, they are reversed and I have used them a few times with much success. | ||
| Koz5150 |
Step 1. Pray to God Step 2. Take the advise listed above Step 3. Pray to God again | ||
| Sportyeric |
I have heard that there is an electrolysis kind-of procedure to deal with such things but I don't know anything about it (yet). | ||
| Phatkidwit1eye |
I was really in a pinch one time when I broke off a bit.I was messing around with a project drilling into an old axel shaft. I broke off a small bit and could not get it out. In frustration I grabbed a small concrete drill bit and with a bit of cutting oil and a few cuss words, I was able to drill it out. | ||
| Chris_mackay |
If you have access to a welder and a steady hand you could build up the drill bit and attach a "T" to it and simply unscrew it. Since the surrounding material is aluminum it should work along with Steps 1 and 3 that Koz listed above. | ||
| Bomber |
EDM (Electronic Discharge Machining) will dissoev the part leaving the base material untouched -- it ain't expensive either (although I wish I didn't know that) -- tough part is gett the part to the guy (most aren't thrilled about standing on their heads working on the whole bike) | ||
| Dsergison |
the alum trick will work. build a dam of putty or clay around the part and fill with solution. but then, it is scary isn't it? you tried your question here? : www.practicalmachinist.com www.homeshopmachinist.net carbide endmills will work to cut out even hss taps. I forget if you have access to a mill. a few sources I dug up. http://www.metal-club.org/Remove.html http://bbs.homeshopmachinist.net/Forum3/HTML/000492-2.html http://bbs.homeshopmachinist.net/Forum3/HTML/000492.html http://yarchive.net/metal/tap_remove.html (Message edited by dsergison on March 22, 2005) | ||
| Rokoneer |
Thank you for the suggestions. The biggest issue with welding onto the snapped off bolt shank is that it is snapped off in my Firebolt's frame, it's one of the bolts that holds (held?) the airbox base to the frame. With the frame being the fuel tank that puts welding at the top, or is it bottom, of the list of risk versus benefit things to try. I have a diamond Dremel bit so it looks like perhaps I'll try that avenue first. I had read last night where Gentleman Jon suggested putting some Lok Tite Thread UNlocker on the bolt to break the Lok Tite bond so I went looking for such an animal today and was greeted by more than one blank look from various people. I see that Jon has since edited his post eliminating the UNlocker term. I have used a soldering iron on the broken off bolt in a feeble attempt to use the heat generated to break the bond, and maybe it has, but I was too busy breaking off the drill bit to find out if the thing would turn... Wycked, I attempted to get a picture of this mess today, but my 5 year old digital camera wouldn't allow me to get a picture of something that small and be anywhere near in focus. Maybe I should finally read the owners manual........ Thanks again! | ||
| Reepicheep |
Be careful and methodical, but don't freak out if you end up having to just drill it out and put in a heli-coil. I have had very good luck with them. | ||
| Xbduck |
Rokoneer, I don't know if I'm to late to help or not but here is my .02. If you can get the end of a center punch on the broken drill bit, CAREFULLY tap at it trying to back it out. Sometimes the broken bit will come out or break into smaller pieces that are easier to remove. I have found that most bits that have broken have shattered farther down the hole as well. If you do not have any stainless left from the broken bolt to shield the threads from the punch you must be even more careful. | ||
| Blake |
As little time as it would take to tack a nut in place, I'd personally try that approach. Gasoline will not burn or combust unless it has air/oxygen present as well as an ignition source. With a full tank of gasoline, one would be providing neither in your case for welding a nut to the broken off bolt surface. An empty or part empty tank would present a serious risk. But certainly if you are not comfortable doing so, then please do not. It is indeed always a dangerous thing to weld or use fire anywhere near to any supply of gasoline. Experience and care are required in good measure. | ||
| Chris_mackay |
In addition to what Blake said, if you understand the properties of aluminum and steel and sit back and think about it, this would be a really good idea. The steel bolt will heat up. The surrounding aluminum will draw heat from steel. At a certain point the aluminum is going to open up and free the threads (as much as it's ever going to). But if you wait too long it'll just get tighter until it cools. When's the right time? I guess when it comes out. | ||
| Swampy |
CHECK THIS OUT www.aldn.com | ||
| Philip |
i saw an article in a car craft magazine that heated up the part with the broken bolt and melted parafin wax onto it. let it cool and it comes out easily. have not tried it myself but worth a shot after you get the drill out. philip | ||
| Swampy |
I use bees wax all the time to help things out. The wax draws into the parts as it cools. It works great. |
