I have in my hot hands 6 brass turnbuckles 2 1/4 in loing with a 1/4 by 20 left and right hand thread. I'm looking at filling in the threaded portion - re-drilling and tapping to a 3/16 diameter to make adjusters for my pedal height. Will a specific epoxy work? Do I fill the hole with brazing? Do I fill with suitable diameter bolt, cut off & re-drill.....? Is there an insert that will screw in?
Any thoughts would be appretiated.
Reducing hole diameters
Reducing hole diameters
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Eldon
Eldon
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Ross Shafer
- Posts: 189
- Joined: Tue Nov 24, 2009 11:52 am
Re: Reducing hole diameters
There's a slight chance that you could use helicoils, but I think the two sizes are too close for any of your solution ideas to work. Epoxy might work just long enough to give you a false sense of confidence then would certainly fail after repeated pedal stomping. I would imagine that the same company that makes the 1/4-20 turnbuckles also makes 3/16 versions. Unless you use silver solder (not the electronics kind) You'll never get any brazing material very far down those threaded bores without having the whole thing turn into a molten blob. Silver solder like that used by bicycle frame builders is difficult to get to stick to brass sometimes(using the black hi temp flux, which is usually hard to find) can help, but the silver flows out super thin and has very little strength when built up thick. Its intended to be used on close fitting joints.
Instead of making the female threads smaller you could make some little sleeves that slip over 1/4 diameter with a hole to accommodate the to 3/16 diameter on the other end. Braze 'em together (silver if anything is brass or stainless and brass if all the parts are steel). Access to a lathe will save you lots of frustration making the sleeves. Or you could just butt the two different diameter threaded rod ends up against each other and tig weld them or braze them together. Of course results will be subject to your brazing or welding skills.
Why not use the standard adjustable slip collars like George L sells....way cheaper than turnbuckles and loads less hassle than adapting what you've got.
Instead of making the female threads smaller you could make some little sleeves that slip over 1/4 diameter with a hole to accommodate the to 3/16 diameter on the other end. Braze 'em together (silver if anything is brass or stainless and brass if all the parts are steel). Access to a lathe will save you lots of frustration making the sleeves. Or you could just butt the two different diameter threaded rod ends up against each other and tig weld them or braze them together. Of course results will be subject to your brazing or welding skills.
Why not use the standard adjustable slip collars like George L sells....way cheaper than turnbuckles and loads less hassle than adapting what you've got.