Drilling out JB Weld from exhaust bolt thread?

[hillsy]

Giving this all I got. Had a small carbide burr I found and that actually did something then I used my dull carbide end mill on a hand drill and got about a third of the way down. Should I use cutting fluid with a carbide burr? I tried it both ways and didn't find any particularl success. Also what's the next appropriate size tap up from M8. I was thinking 3/8. M10 seems too big for the space I have and M9 is impossible to find as a button cap bolt. Hoping fresh burrs coming this Friday will be the trick. Going to paint the engine while it's off the bike.

Use a TimeSert or Helicoil and bring it back to M8 - then Loctite M8 studs instead of using bolts.

[Kodak]

Those timeserts are pricey. Ain't happening. 70 bucks for a couple taps and a steel insert?!

[chuck hahn]

Yeah but aftr the initial purchase you just resupply the inserts. Compared to a coiled style helicoil its like a Bently compared to a VW bug.

[hillsy]

Those timeserts are pricey. Ain't happening. 70 bucks for a couple taps and a steel insert?!

How much have you sunk into it so far with broken taps, extractors and drill bits? Like Chuck said, you'll have the tools forever and anything you do after this will only cost the price of the inserts.

[Kodak]

I understand what your guys are saying. I know the largest cost so far is the sunk time instead of working on the seat pan and electrics. Fortunately I don't have too much sunk into the tap removal. But you're right about having it for life. I just have to take into consideration when I'll be needing an M8 timesert as opposed to using the carbide burs again that I've just ordered. I will say for as much complaining I've done while drilling this sucker out I'm having a peachy time learning as I go and from everyone chiming in on this thread. I've learned about the various ways to grind out a tap, learned about EDM, tempering, and the cost of not drilling out a bolt all the way before tapping threads! This is what I signed up for when I bought this bike!

[AMK]

I understand what your guys are saying. I know the largest cost so far is the sunk time instead of working on the seat pan and electrics. Fortunately I don't have too much sunk into the tap removal. But you're right about having it for life. I just have to take into consideration when I'll be needing an M8 timesert as opposed to using the carbide burs again that I've just ordered. I will say for as much complaining I've done while drilling this sucker out I'm having a peachy time learning as I go and from everyone chiming in on this thread. I've learned about the various ways to grind out a tap, learned about EDM, tempering, and the cost of not drilling out a bolt all the way before tapping threads! This is what I signed up for when I bought this bike!

Great attitude man. I'm hoping you win this fight.

[2BRacing]

I understand what your guys are saying. I know the largest cost so far is the sunk time instead of working on the seat pan and electrics. Fortunately I don't have too much sunk into the tap removal. But you're right about having it for life. I just have to take into consideration when I'll be needing an M8 timesert as opposed to using the carbide burs again that I've just ordered. I will say for as much complaining I've done while drilling this sucker out I'm having a peachy time learning as I go and from everyone chiming in on this thread. I've learned about the various ways to grind out a tap, learned about EDM, tempering, and the cost of not drilling out a bolt all the way before tapping threads! This is what I signed up for when I bought this bike!

Yes, your learning curve has been quite steep! You deserve compliments for hanging in there so far - others would have quit long ago!

I would like to make you aware of one thing as you move forward and prepare to insert (hopefully) a Timesert in that hole - please be aware that the hole appears to be off-centre towards the bottom-left of the original centre point. You will need to tap and insert whatever fixing you choose on the correct original centre-to-centre hole spacing to the other (good) hole, or else your exhaust collar will not bolt up easily (or if you use studs, they will not go through the holes in the collar easily).

I am holding thumbs for a successful completion of this task!

[Steve]

Compared to a coiled style helicoil its like a Bently compared to a VW bug.

You can have them both, Chuck.



.

[Kodak]

Yes, your learning curve has been quite steep! You deserve compliments for hanging in there so far - others would have quit long ago!

I would like to make you aware of one thing as you move forward and prepare to insert (hopefully) a Timesert in that hole - please be aware that the hole appears to be off-centre towards the bottom-left of the original centre point. You will need to tap and insert whatever fixing you choose on the correct original centre-to-centre hole spacing to the other (good) hole, or else your exhaust collar will not bolt up easily (or if you use studs, they will not go through the holes in the collar

I didn't think about this. I knew I was slightly off center. With the engine off the frame I can align my drill far better. Hmmm, maybe I can think of something to ensure I'm drilling on center despite the crappy oblong opening I have to start with.

[hillsy]

I didn't think about this. I knew I was slightly off center. With the engine off the frame I can align my drill far better. Hmmm, maybe I can think of something to ensure I'm drilling on center despite the crappy oblong opening I have to start with.

You have a Dremel / die grinder? Use it to "centre" the hole before you drill it for the tap.

[Kodak]

You have a Dremel / die grinder? Use it to "centre" the hole before you drill it for the tap.

Yes I do! I purchased a grinding stone for it and that actually helped make a dimple in the tap for me to grind some of it out. My center punches just shattered at the tips when I tried to punch the tap. I will say part of me wishes the tap was Chinesium and not made in the USA. Maybe they would have dissolved in my alchemist potion! Haha!

[jdion81]

Maybe they would have dissolved in my alchemist potion! Haha!

I hear you have to apply heat when using the Alum, have you tried that yet?

I am interested in this, since I have a head that is mostly good, with the exception of 6 broken off exhaust bolts. I am faithfully watching your thread to learn what works.

[Kodak]

I hear you have to apply heat when using the Alum, have you tried that yet?

I am interested in this, since I have a head that is mostly good, with the exception of 6 broken off exhaust bolts. I am faithfully watching your thread to learn what works.

So this is our dilemma, with the motor off the bike we've got great access to the bolts or in my case the broken tap, which makes creating a reservoir to hold the concoction easy. Heating it however is that real task. I can't think of a way that is safe to leave unmonitored for 24hrs+. I've had success with left handed twist drill bits for bolts. I've soaked them in PB blaster for several days. Heating up the area and letting it cool down a bit. This is my first trial with a broken tap. Harder in the most double entendre possible.

[Kodak]

Major update...coming later tonight. Just thought I'd give a little teaser for anyone following this thread. Got most of the tap out, found out how bad I done messed up attempting to tap the hole originally, it's embarrassing but I'm posting the pictures in the name of technical endeavors, I've retapped and helicoiled the hole. I will defend my position on purchasing a helicoil over a timesert tonight, and finally found out with great results that alum solution does dissolve a tap...Pictures and musings to come!

[60ratrod]

yeah, broken taps blow big time! I had to do head gaskets on the 72 gmc c15 I had forever ago and while trying to clean the threads in the block(the last one or two holes I had to do of course) the tap snapped. I almost ended up pulling the motor, but we were able to build enough heat on the tap to get a nut to stick to it with a mig welder. that was about 5-ish nuts. and I tried just about everything including the tap extractors. extractors won't do anything on a jammed in tap.

one thing that I noticed from the alum thread that was posted is that the alum takes quite a bit of time, and perhaps you were just getting a little impatient, especially with a hardened item like that?