Conncave Conn? "Project Conn"

[DavidUK]

Following on from my previous threads, I was polishing the Pan Am yesterday when I noticed the body may be curved....

It appears to be a relaxed uniform curve with the strap ring being at the "apex", OR it's an optical illusion. You can also see a slight curve in one of the rods in the bottom photo. The opposite curve at the lower end of the Low C rod in the top photo is due to the lower post having been resoldered slightly counter-clockwise. I'll get this corrected too. I can't tell if the curve affects playability but you'd think so wouldn't you?

What would have caused it to become gently curved?

When I take it to the tech for the dent work, is there an accepted and straightforward way of straightening the body tube, or is it just its 70 years of age showing!?

Thanks for any advice.

 

[Ads]

My MkVII was slightly banana shaped - it was the best sounding Selmer Tenor I have encountered to date (though it was one of the first VIIs made) . I can`t remember if it was always that shape from when I got it and it gained leaks gradually over the decades rather than after one incident but it didn`t seem to do it any harm (we`ll see when its new owner gets the total rebuild done)

 

[DavidUK]

I think it may be a "best left alone" situation as I can't imagine how it could be corrected. Plus there's the cost....

 

[DHM]

is there an accepted and straightforward way of straightening the body tube

 

[DavidUK]

Looks straightforward.... I'll get me broom handle.....

 

[kernewegor]

If it isn't an optical illusion I guess the only way to correct it is to strip it, remove the bell, unsolder the octave tube, put it on a mandrel and anneal and hammer as appropriate. Not difficult on a tapered brass tube...but...it isn't just a tube - the big problem is the tone holes. Soldered ones could be removed and replaced afterwards, but drawn ones would have to be worked around - if that is possible.

If it plays well as it may be best to leave as is.

I foresee a chat with your techie...

Edit: Just saw the video! Wow! That looks more like it! In most trades knowing how and where to thump things is crucial - I used to be a boatbuilder...

This could be an affordable solution. Look forward to hearing what your techie says!

 

[DavidUK]

A steel straight edge inside the tube will give a better idea than trying to squint around all the gubbins on the outside and peering against all the reflections and visual distortions on the inside.

If it isn't an optical illusion I guess the only way to correct it is to strip it, remove the bell, unsolder the octave tube, put it on a mandrel and anneal and hammer as appropriate. Not difficult on a tapered brass tube...but...it isn't just a tube - the big problem is the tone holes. Soldered ones could be removed and replaced afterwards, but drawn ones would have to be worked around - if that is possible.

If it plays well as it may be best to leave as is.

I foresee a chat with your techie...

Did you watch the video at #4? Seems very simple.

 

[kernewegor]

Did you watch the video at #4? Seems very simple.

Are you going to have a go yourself? A body slammer looks easy to make...

 

[kevgermany]

Was probably dropped at some point.

If it plays well as is, don't try and straighten it yourself. You'll probably introduce leaks and cause binding in the keys. Definitely a tech's job.

 

[griff136]

+1 on what Kevgermany said.

don't bother with a broom handle either - you need something solid. I make these body tools as I need them - I've got a dozen or so - all slightly different diameter for a real snug fit in the receiver end of the body (easy to make if you have a lathe) I also prefer to leave the keywork on the sax.

 

[DavidUK]

The broom handle was a joke...
Griff, are the slammers standard kit for all techs?

 

[DHM]

Looks straightforward.... I'll get me broom handle.....

A pair of stout Brave Trousers™ would be a good idea.

 

[griff136]

David, It's the way I was taught at college and it's the way most tech's would do this sort of job for a gentle bend. It's just one method of getting a body straight. There are single mandrels and overlapping "tapered" cones which screw into a rod which the body tube can be pushed onto to get the tube straight and the bore inside rounded again. If there are loads of dents and a couple of creases and mis-shapen tone holes, then using the "slam" method would only go so far in straightening the tube but wouldn't address any of the other issues.

 

[DavidUK]

You'd think slamming could be rather inexact and could leave an "S" shaped tube? Is there some science behind it or is it just pot luck?

 

[Colin the Bear]

Does it play? The thing with watching an expert, making things look simple,is that they're an expert, with experienced hands. Why risk banging anything if it plays?

 

[griff136]

You'd think slamming could be rather inexact and could leave an "S" shaped tube? Is there some science behind it or is it just pot luck?

David, it takes time and practice and know how. Just like any other acquired skill. Too hard a blow and. You can easily bend the tube too far the other way and distort toneholes.

 

[DavidUK]

Don't panic!
It's going to Connolly-MIR for the dents and I'm sure Matt or Charlie will advise on the curve too.
I shalln't be banging it myself, not even with my arm clamped in a vice again!

 

[jbtsax]

The way I was taught it is very important to know where and how you hold the body of the sax as you give it a whack. On an older sax that has gradually become bowed over time with the keys moving freely and the pads seating properly, you could be opening a can of worms by straightening the body in this fashion. On the other hand if the sax has been dropped resulting in a bent body tube, misaligned pads, and binding keys then the best and easiest solution is to recreate the blow that caused the damage going in the opposite direction. In this situation I agree with Griff that it is best to leave the keys on for this procedure.