[davevillajr]

Hello all techs and tech-minded people, I have developed a problem with the neck screw on my AS100 sax.

The dang thing is sticking, sometimes so badly, I can't tighten or loosen it.

I've tried swapping the lyre side screw for the neck screw, but it doesn't help much.

The "clamp" is the standard Selmer VI/VII, split ring tenon reciever clamp with the tightening screw on the right and the lyre screw on the left.

I have noticed the tang side of the tenon receiver that the screw passes through before the threaded tightening portion seems bent TOWARDS the threaded part. Instead of "parallel" lines being suggested by the split portion, they would be "intersecting" lines.

I don't have time to take it into the tech today, as I NEED to play it tonight and tomorrow.

Should I try to open up the split and re-parallel the clamp, or chase the threads on the horn and screw with a tap and die? If tap and die, what number size would it be? I really don't want to screw it up, but it has become almost IMPOSSIBLE at times to loosen the screw.

Thanks,

dv

 

[bandmommy]

A 'slight' misalignment 'shouldn't' make the screw hard to turn.
Have you tried removing it and putting a drop of key oil or a little gob of cork grease on the threads to help slick things up a little?

 

[davevillajr]

Yeah mom, it didn't help.

I thought maybe something was in the threads, so I ran a pipecleaner through it with some oil on it to see if anything stuck, but no dice.

It's a mechanical binding issue I think, not frictional. If I'm not careful about where I stop tightening it gets stuck so hard I can't even turn it. Almost feels so tight I'd have to get pliers out to turn it back.

I've not done that, but that's how stuck it gets.

dv

 

[Stephen Howard]

You have to look at why the screw socket has bent. It's often the case that the socket has come unsoldered from the tenon sleeve, which allows it to distort. The only fix for that is to have it soldered back on - but it's more of a problem on older horns really.

I wouldn't advise messing with the socket or threaded section - let a repairer have a look at it - but in the meantime there are a couple of options.

Pack out the tenon sleeve with PTFE tape so that it's a tight fit without the screw - or, saw a section of the thread off from the screw. A screw really only works on a fraction of it's length - so turn the screw in until it starts to lock, note the distance from the end of the screw socket to the shoulder of the screw, then remove that much plus a tad extra from the screw thread.
You should be OK, as long as there's at least around 5mm of thread left - though 10mm would be a more comfortable minimum.

Regards,

 

[davevillajr]

Update - the sleeve is soldered nice and tight all the way around. I can see the flex in the "pass through" for the screw when tightening - so it's NOT bent, just an optical illusion.

Today it ran in and out just fine with no binding. Weird.

I think I'm going to take your advice Stephen and just lop off a couple of threads and see if that helps.

Thanks for all the suggestions - it's a strange intermittent problem.

dv

 

[Stephen Howard]

Sounds like you might have had a piece of swarf in the threaded socket - perhaps a piece of thread became detached. A pipe cleaner wouldn't shift it, but removing the screw and re-insterting it might have done.
If it's working now, leave it alone.

Regards,