planet x alan Posted September 19, 2011 Report Share Posted September 19, 2011 The tap has well and truly snapped off inside the mount and not retreivable using long nosed plyers or anything like that. In hindsight i should of used better quality stuff for the job! The question is: If i were to drill the whole lot out would it be worth it/possible for an aluminium welder to fill the mount back up and for me to re drill/retap the mount. Would the heat involved weaken the frame in any way? Bodged it together with a jubilee clip atm and it's holding up well enough but would be nice to be able to fiddle about with brake set up while out riding! Any input appreciated. Quote Link to comment Share on other sites More sharing options...
AdamR28 Posted September 19, 2011 Report Share Posted September 19, 2011 Google local engineers, find someone who does spark erosion Depending on the frame, may be cheaper just to buy a new one unfortunately Quote Link to comment Share on other sites More sharing options...
planet x alan Posted September 19, 2011 Author Report Share Posted September 19, 2011 Depending on the frame, may be cheaper just to buy a new one unfortunately Yeah that's what i was thinking. I'll have a look around but the jubi clip will probably have to stay on there a lot longer than i hoped! Thanks for the quick reply! Quote Link to comment Share on other sites More sharing options...
GyTrials Posted September 19, 2011 Report Share Posted September 19, 2011 could you not drill the tap and then have an opposite thred tapped in, obviously then just tighten bolt up untill tap comes out of frame. i might just be thinking of something that doesnt exist Steve Quote Link to comment Share on other sites More sharing options...
Ali C Posted September 19, 2011 Report Share Posted September 19, 2011 Oh you in trouble!! Quote Link to comment Share on other sites More sharing options...
Revolver Posted September 19, 2011 Report Share Posted September 19, 2011 (edited) Do you mean you had a helicoil that's failed? Oh, I understand, you were redoing the brake threads. Edited September 19, 2011 by Revolver Quote Link to comment Share on other sites More sharing options...
WIGAN ?? Posted September 19, 2011 Report Share Posted September 19, 2011 is the tap flush to the top of the mount ? try cutting a slot into it for a screwdriver to fit into, you may have to cut into your frame a few mm but its better than having a tap stuck in there Quote Link to comment Share on other sites More sharing options...
AdamR28 Posted September 19, 2011 Report Share Posted September 19, 2011 The tap will not come out by drilling, or by cutting a slot in it. There's been a LOT of torque applied to it in order to snap it, and it's too hard for pretty much any drill bit. Quote Link to comment Share on other sites More sharing options...
Ali C Posted September 19, 2011 Report Share Posted September 19, 2011 I repeat Oh you in trouble!! Quote Link to comment Share on other sites More sharing options...
24martin Posted September 19, 2011 Report Share Posted September 19, 2011 i've snapped a couple M6 taps before and managed to hit the the broken part of the tap with a decent center punch (and a hammer) untill the tap had pretty much disintegrated, then cleaned up the mess by drilling it all out and inserting an 8mm thread insert, bringing it back down to M6. i'm not sure how well this would work on an M5 brake bolt, on a frame, becuase im not sure if you can clamp a frame in a vice and hit the living sh*t out of it with a hammer... if you were going to keep the frame as a spare it may be worth a try! Quote Link to comment Share on other sites More sharing options...
liam n Posted September 19, 2011 Report Share Posted September 19, 2011 i understand this probably wouldn't work with a something so small but with my crank bolt....it was completely rounded and in the end couldn't get the bolt out. so went to ally welder and he welded a metal bar to the crank bolt and put a mole grip/pipe grip on it, and with lots of pressure managed to undo the crank bolt with out breaking threads... so a welder could possibly tac a metal bar on to the tap and you could unscrew it Quote Link to comment Share on other sites More sharing options...
planet x alan Posted September 19, 2011 Author Report Share Posted September 19, 2011 Thanks for the suggestions guys, the idea of welding a bar onto it i could not seeing work, it's a 4mm hole so he'd heve to be a pretty shit hot welder to get a bit of steel in there without melting my brake mounts to bits. As for cutting a slot, as Adam said there's been a bit of torque gone through it to shatter it (Yes I did go at it with brute force and ignorance and paid the price!). I think my plan of action is gonna be to live with it with a jubilee clip holding it on until a decent frame pops up for sale cheapish! Quote Link to comment Share on other sites More sharing options...
Ashley Smith Posted September 19, 2011 Report Share Posted September 19, 2011 removing a broken tap is no problem at all, providing you use the correct equipment,its something i do on a day to day basis. in your case you need to use a carbide centre drill, followed by a carbide drill bit, preferably a spade drill, you need to run both of these at quite high speed, once youdrill a gole through the broken bit of tap, it would be possible to shatter the outer parts of the remaining tap and it should fall from the thread, the other option which you have is to shatter the tap with a good punch and a big hammer. relatively easy for someone with basic engineering skills, try your local engineering firms, they'l get it out no problem at very little cost. ash Quote Link to comment Share on other sites More sharing options...
planet x alan Posted September 19, 2011 Author Report Share Posted September 19, 2011 shatter the tap with a good punch and a big hammer. May give that a go actually, they are hardened steel so VERY brittle when smashed. Quote Link to comment Share on other sites More sharing options...
Ashley Smith Posted September 19, 2011 Report Share Posted September 19, 2011 best option is to spark it out, but obviously that isnt an option, so i would drill it, as a last resort id try to shatter, the problem with that though is that it might push the tap further down the thread causing more damage. Quote Link to comment Share on other sites More sharing options...
planet x alan Posted September 19, 2011 Author Report Share Posted September 19, 2011 Yeah good plan. The drill bits needed look pretty inexpensive so I'll give that a try when i have a bit of time spare! Thanks! Quote Link to comment Share on other sites More sharing options...
Greetings Posted September 19, 2011 Report Share Posted September 19, 2011 Once got a tap stuck in a hub axle, got it out by cutting a slot in it using an angle grinder. What remained of the axle was just about long enough to suport the wheel in the dropout. Drilling it out or even drilling a tiny hole in it is nigh on impossible due to how hard the material is. Quote Link to comment Share on other sites More sharing options...
Filo Posted September 20, 2011 Report Share Posted September 20, 2011 You can't drill taps.the drill will just rub and you will get no where. Using a diegrinder with a carbide burr could work. If you have access to tooling make up a little spanner that fits Into the tap flutes. Something with 3 fingers that fit between the tap and the hole in the material. Make the fingers as long as the broken tap. Use a tap wrench on the top to unscrew it. Aslong as you have maximum contact on the tap you should be all good. I can draw you a picture of what I mean If you don't understamd Quote Link to comment Share on other sites More sharing options...
JD™ Posted September 20, 2011 Report Share Posted September 20, 2011 The obvious solution here is to grind off your mounts and go brakeless Quote Link to comment Share on other sites More sharing options...
dave33 Posted September 20, 2011 Report Share Posted September 20, 2011 (edited) Ok I have not read all the thread. BUT I am an engineer! Don't waste your time listening to people who are just guessing You should be able to get the tap drilled out with a carbide drill, or by using a carbide burr, but you will need to clamp it and use a pillar drill! Probably best taking it to a local engineer, and one decent should beable to sort it! The tap will not come out by drilling, or by cutting a slot in it. There's been a LOT of torque applied to it in order to snap it, and it's too hard for pretty much any drill bit. Edited September 20, 2011 by dave33 Quote Link to comment Share on other sites More sharing options...
AdamR28 Posted September 20, 2011 Report Share Posted September 20, 2011 Cool - just speaking from personal experience there, but if you have been able to do it in the past then defo worth a shot before resorting to spark eroding it or scrapping the frame. Quote Link to comment Share on other sites More sharing options...
monkeyseemonkeydo Posted September 20, 2011 Report Share Posted September 20, 2011 Spark eroding is easy and really cheap... well, it is when you know someone who knows someone and work at a university! M8 tap snapped deep inside my motorbike front axle and they did an excellent job of it and all for a bag of doughnuts! Quote Link to comment Share on other sites More sharing options...
Matt Vandart Posted September 27, 2011 Report Share Posted September 27, 2011 f**k me, how complicated is this getting? Smash it out and helicoil it. Quote Link to comment Share on other sites More sharing options...
Muel Posted September 27, 2011 Report Share Posted September 27, 2011 I'd get a carbide drill bit down the centre, then smash the rest into pieces with a nail and a big hammer. Job done. Never had to do it because I've never managed to snap a tap in an aluminium thread, but I know some more ham-fisted people who have. Quote Link to comment Share on other sites More sharing options...
weirdoku Posted September 27, 2011 Report Share Posted September 27, 2011 (edited) Get a drill bit that's slightly wider than the 3/4 grooves (for the swafs) that run down the threads of the tap. Drill down the middle of the tap. Make sense? Edited September 27, 2011 by weirdoku Quote Link to comment Share on other sites More sharing options...
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