Stuck brake adjuster advice sought

[Darcus]

Hiya, how would you remove this without heat? I've tried so far gently twisting with a wrench and GT 40 application. I don't want to apply heat and damage the paint. Alloy component meets steel Thanks! I'm thinking of drilling next but will need to go easy!

 

[27motorhead]

The adjuster looks like steel to me? Is it magnetic? I'd look to be using penetrating fluid/WD40/GT85 as you have been doing. I'd look to file a flat on the head for a good grip (looks like you might have done that?) and use good mole grips or locking adjustable spanner to try and remove/prevent slipping.

I think you've tried all this though?

Next step would be to drill it out from the inside using a pistol/cordless drill from the bottom of the adjuster.

I'd slowly increase the drill bit size. I'm lucky have a nice Dormer set that go up up in 0.1mm increments, but a set which go up by 0.5mm should suffice. If the adjuster is M5 the tapping drill is 4.2mm DIA which means if the hole is central (concentric) to the thread then by the time you get to around 4mm and you twist the top with your wrench it'll probably start to collapse and twist out. Maximum size I'd probably drill out is about 3.5mm and try and unscrew, if still stuck then I'd jump up to a 4mm. You can get cheap carbon steel taps if you need to clean out the thread on the frame.

ALSO, this is assuming it's an M5 adjuster! Measure the thread, this should be around 5mm (but probably less from the threads being rolled/formed.

 

[hamster]

I agree with all the above - but there scope to heat shock it first to try and crack the bond. Try a kettle full of boiling water.

Plus-Gas works far better than GT85 or WD-40.

 

[27motorhead]

I agree with all the above - but there scope to heat shock it first to try and crack the bond. Try a kettle full of boiling water.

Plus-Gas works far better than GT85 or WD-40.

100% agree with @hamster with boiling water, won't harm the paint on that delightful Roberts either. And yes PlusGas is superior to WD&GT, but appreciate not everyone has some. Worth buying though if you like old bikes!

 

[minor_LEGEND]

Will it tighten in by half a turn before trying to wind it out?

 

[Darcus]

The adjuster looks like steel to me? Is it magnetic? I'd look to be using penetrating fluid/WD40/GT85 as you have been doing. I'd look to file a flat on the head for a good grip (looks like you might have done that?) and use good mole grips or locking adjustable spanner to try and remove/prevent slipping.

I think you've tried all this though?

Next step would be to drill it out from the inside using a pistol/cordless drill from the bottom of the adjuster.

I'd slowly increase the drill bit size. I'm lucky have a nice Dormer set that go up up in 0.1mm increments, but a set which go up by 0.5mm should suffice. If the adjuster is M5 the tapping drill is 4.2mm DIA which means if the hole is central (concentric) to the thread then by the time you get to around 4mm and you twist the top with your wrench it'll probably start to collapse and twist out. Maximum size I'd probably drill out is about 3.5mm and try and unscrew, if still stuck then I'd jump up to a 4mm. You can get cheap carbon steel taps if you need to clean out the thread on the frame.

ALSO, this is assuming it's an M5 adjuster! Measure the thread, this should be around 5mm (but probably less from the threads being rolled/formed.

Brilliant and thanks for this. It was going to be my approach, I doubt I have a large range of drill bits, but will see what I've got, and make a selection . I'm thinking slow and gentle drill speeds, maybe the battery one first!

 

[Darcus]

Will it tighten in by half a turn before trying to wind it out?

Good idea, its had gentle wiggles in both directions so far

 

[Darcus]

I agree with all the above - but there scope to heat shock it first to try and crack the bond. Try a kettle full of boiling water.

Plus-Gas works far better than GT85 or WD-40.

Definitely the next thing I try. Maybe a nice redox bath first to seduce.

 

[Betsy]

Try using a hacksaw to cut a slot into the head wide enough to fit a slotted screwdriver.. use a screwdriver with a square or hex shaft.. put the screwdriver head into the slot, clamp mole grips around the screwdriver shaft, push down on the driver and turn the grips..

If this doesn’t work, you can hacksaw in from the opposite side and use the same method to split the bolt down the length, it will usually free up one half and allow you to wiggle it free.

 

[27motorhead]

One thing to watch out it to make sure you're drilling square with the adjuster so you don't go off centre. Small incremental drill sizes with minimal force will help this. Potentially the seat stay bridge might get in the way from you holding the drill square? Watch the drill and it's chuck against the paint on the seat stay bridge! May want to put several layer of masking tape around it just in case!