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It frustrates me to no end when I see butcher jobs like this happen, good to see john came to your rescue.

Just in case some one else has the same situation

My process for the repair would have been to remove the post, cook it in some alum to get rid of any old steel grub screws, then using hard solder fill the post damage back in and file it all smooth, redrill the hole and insert a new screw.

This retains the original post and makes it functional and aesthetically pleasing
 

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Maybe I missed it but I don't think it was mentioned what this actually is? This is an unfortunate old method of trying to remove screws with damaged slots. Even more unfortunate that it's probably still used now, though at least not as much. Basically someone uses some kind of saw to cut a slot in the screw, and cuts the post along with it. It's not that common, but you see this occasionally both for Conn set screws and for pivot and rod screws on any model sax.

There are two problems with it. First, it damages the post, and second, if the slot is ruined it usually means the screw is stuck, so there is even more chance of them repeating this, ruining it even more, etc.
In this case it probably didn't work in one direction so they tried another. Not that I would ever suggest this method, but in this case it looks like whatever they used to cut was too thick anyway and would never work, damage to the post or not.

Sounds like the problem is solved and the post will be replaced, but FWIW, with the ability and the right tools, it is actually possible to cut a new slot in a screw buried in a post with a damaged slot, without damage to the post. It works in most cases, in fact it nearly always does. It is extremely rare that I have to resort to alum or anything like that, which is what I do too when nothing else works. It is not really possible to do with a regular dremel, not enough precision and control (it wouldn't be surprising if that X was done with a dremel).
Of course that doesn't solve the (most likely cosmetic) issue of the X there, but that is a separate problem and depends on time, budget, availability, etc.
 

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Forum Contributor 2016-17
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Discussion Starter · #24 ·
Maybe I missed it but I don't think it was mentioned what this actually is? This is an unfortunate old method of trying to remove screws with damaged slots. Even more unfortunate that it's probably still used now, though at least not as much. Basically someone uses some kind of saw to cut a slot in the screw, and cuts the post along with it. It's not that common, but you see this occasionally both for Conn set screws and for pivot and rod screws on any model sax.

There are two problems with it. First, it damages the post, and second, if the slot is ruined it usually means the screw is stuck, so there is even more chance of them repeating this, ruining it even more, etc.
In this case it probably didn't work in one direction so they tried another. Not that I would ever suggest this method, but in this case it looks like whatever they used to cut was too thick anyway and would never work, damage to the post or not.

Sounds like the problem is solved and the post will be replaced, but FWIW, with the ability and the right tools, it is actually possible to cut a new slot in a screw buried in a post with a damaged slot, without damage to the post. It works in most cases, in fact it nearly always does. It is extremely rare that I have to resort to alum or anything like that, which is what I do too when nothing else works. It is not really possible to do with a regular dremel, not enough precision and control (it wouldn't be surprising if that X was done with a dremel).
Of course that doesn't solve the (most likely cosmetic) issue of the X there, but that is a separate problem and depends on time, budget, availability, etc.
Yes, whatever was used to cut the +, it was much thicker than e.g. a jeweler's saw. The appearance of the + in relation to the surrounding material also makes it look like it was done quite some time ago, but that is just speculation on my part.

For future reference, what tool would you use to cut a new slot in a buried screw?
 

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I do it with a dental micromotor and a tiny reversed taper bur (I prefer that type though other tiny burs are also possible).
I have a dental micromotor as well but I still can't figure out how I could get a Conn lock screw out without the use of alumn. What size taper do you use? I've seen none in a small enough size.
 

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I mostly use reversed taper burs, if I remember they are as small as 0.5mm diameter. If I really need something smaller there are ball burs down to 0.3mm. The Conn set screws are about 1.85mm diameter with approx 0.45mm wide slot. I'm not sure if I used the reversed taper or the ball for these, but most of the time it works. Usually this is at about 30K to 40K RPM.
It doesn't work 100% of the time, but by far most of the time it does. I only had to resort to alum maybe three or four times in the last... maybe 15 or so years. Not just for set screws, I mean in total (so maybe once or twice for set screws).

What dental micromotor do you have? If it's a good one it should have enough precision and control for this. I think even the cheap ones would probably be ok because it is at this high RPM (though I haven't tried this specifically with a cheaper one). Some people mean a flexible shaft rotary tool which doesn't have nearly as much control and precision.
 

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It's moot to solving the OP's issue since he has a replacement post with pivot screw and set screw, but keep in mind that to save the pivot screw yo have to completely remove the set screw. If you try to turn the pivot screw out past the end of the set screw you'll ruin the threads on the pivot screws. I think that if you dissolve the set screw in alum you'll also ruin the pivot screw at the same time.

Old school was to cut the top of the post in half, spread it apart enough to get the pivot screw out, and proceed from there. I have a couple posts on my baritone that show evidence of this procedure. Surprisingly enough it doesn't appear to have caused any long term harm, but I'd rather not see it.
 

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Yeah, I've used drills as small as 0.3mm but not for this. Another problem is that the surface of the damaged slot is usually very irregular with cuts and burrs, so the drill grabs and either doesn't turn, or breaks the moment it grabs (even much larger drills). If you first use a bur that cuts and leaves a flat surface (like an end mill) it might work. There are ways to minimize the drills breaking, though I probably wouldn't bother.

For the slot you need a bur and not a drill. I prefer the reversed taper burs mainly because it's easier to not have a tapered slot. I don't remember if these are available as small as 0.5mm or maybe 0.6mm and I'm pretty sure this worked even for Conn set screws. It's definitely worth having some even smaller ball burs. Use the best screwdrivers and make sure they are sharp.

If the Saeyang is one of the higher torque brushless motor models, it's excellent. It's exactly what I recommend for a little lower price than the German or Japanese models. It's more than good enough to use it for this purpose and the million other things a micromotor is good for.
 
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