Swedging the unswedgable

clarnibass

clarnibass

Hi

I'm wondering how other repairers (or anyone) would fix a loose keys that have stuff soldered to them on the entire length of the hinge tube. For example F/C key on Buffet clarinets. Also I'm talking specifically about a situation where major repairs for this are not possible e.g. making a new slightly thicker rod screw, removing end-play by soldering an extension, etc. Consider that these types of repairs are not an option in this situation. Is there a solution that can work for people on a budget, etc.?

Thanks

Nitai
 
Create an insert of some kind? A while back I did something with epoxy but I'm sure one might get better results with Delrin, Nylon or even soft solder.

I'd think the attached picture is self-explanatory.

And if you cannot extend the key/rod, you can build up the pillars a bit...
 
Thanks for those suggestions and the photo. However there are some problems.

IME glue is simply not reliable enough in places where two parts slide against each other and a lot of accuracy is needed. Like a key on a rod screw or (even more) the end of the key against the post. I've tried several strong glues for situations similar to this as experiment and never liked the result, just wears too fast. Though I like glue for situations where there is rarely ever movement, for example ro remove play from inside posts.

I've tried solder by itself to extend keys, usually something like soft silver solder (e.g. 96/4 tin/silver) as opposed to soldering a (brass) extension. This actually works very good! Doing the same to a post can work also. But the solder will get to the hole and be too long so the fitting required after is significant. BTW re your photo, maybe you drew it this way just for the example, but I found it is better to drill from the other, open side. Then do the final fitting with tools more accurate than drills. It is not really a budget repair.

Thanks again for your suggestions.
 
Nitai,

what is the problem with that key exactly? Is the hinge tube too short? Is the hinge ID too large? Both? Something else?

(Re the aforementioned glue - I used 2 component epoxy aka Araldite or the like, and found it very durable. I'm sure there are other things like liquid metal but I had no opportunity yet to try it)

Oh, and if the key is rattlying and short, you can use a bronze or brass bushing/bearing (in lieu of the red glue, and instead of a conical hole make a cylindrical one). If the bushing protrudes from the tube, file off as necessary.
 
I'm slightly confused too

If you solder fill the hinge tube to get rid of looseness etc there are tools in which you can quickly reshape to hole for pivot screws, and also using a hinge tube shortener you can make the end square.

If you are extending a key, ie cutting off a piece to make room to add a longer length then that's different. excluding spare parts etc soldering two rods together can be tricky especially to keep them straight. you have to use rod inside to make sure it is straight while soldering. Then give the rod a tap/whack to dislodge it then use inside files to file smooth.

you could also use a sleeve from large keywork tubes on the outside to make it a faster fix though much more visible. other thinner options such as sleeves, or thin tubing from pen making or other thin walled tubing you can get at a hardware store is an option.

If you need to extend a key very slightly then there are tools for that too.

Usually the most annoying issues is when the key is loose and there's keywork off the edge. Then solder fill is the quickest way to go. Especially on the lower part of the key which, over time, gets more worn and usually unevenly worn.
 
tictactux said:
what is the problem with that key exactly? Is the hinge tube too short? Is the hinge ID too large? Both? Something else?
Click to expand...
I mean end play plus loose around the rod, but there is no key. My question is in theory based on keys I've seen before. In the past, I used one of the solutions that work that I mentioned. Or instead, if the problem was very small, sometimes thick oil or grease can be a temporary repair (with no charge).

What made me think of this is a Chinese clarinet that was obviously a matter of (not a lot of) time until this would be necessary. It would be a bit crazy to invest much since the clarinet was so cheap, but not repairing could mean the player wouldn't have a reliable clarinet. Many pads on the clarinet were tearing and I'm sure this one would tear soon enough.

tictactux said:
Re the aforementioned glue - I used 2 component epoxy aka Araldite or the like, and found it very durable.
Click to expand...
I've tried glues like this, very strong 2 part epoxy. I thought it was not reliable enough for situations like these. I would use solder like I have in past also because waiting for the glue to dry would take much longer than the entire repair with solder.

SteveSklar said:
I'm slightly confused too

If you solder fill the hinge tube to get rid of looseness etc there are tools in which you can quickly reshape to hole for pivot screws, and also using a hinge tube shortener you can make the end square.
Click to expand...
I use the term pivot screws when I mean point (or pilot) pivot screws. I'm asking about rod screws only, where the entire screw is inside the key hinge tube.

Filling/extending with solder is one solution that I've done. I have hinge tube shorteners. This is the type of repair that is not cost effective in the those situations. Soldering an extension is more expensive.
 
one quick method that I employ on student/intermediate clarinets is from the use of teflon sheets.

Teflons sheets come in different thickness and one can use a paper-type hole punch (craft store) to get small circles, then a spring-type punch to get the inside hole.

Then that piece can be used to fill in a small gap between the key and the post. This can eliminate slop and is rarely seen by players.

A cheap and fast solution and seems to last a very long time.


also, same method - little steel washers that can be found at hardware stores that have drawers and drawers of misc stuff. If diameter is too much one can always put it on a dremel with a cutting head (with the washer instead of the cutter) and with a file sand it down a bit for proper diameter. You could also fashion some from sheet metal.
 
OK, here is the old fashioned way to do this job. It may be in the old Erick Brand manual, I'm not sure.

Put the hinge rod into the hinge tube on the key. Drill a hole the diameter of the hinge rod into a block of steel. Insert the hinge rod into the hole in the steel block and butt one end of the hinge tube up against the steel, with the rod inside. Use a semi-pointed punch and punch shallow holes in the other end of the hinge tube on its flat face with the hinge rod in place.

The small "dimples" in the flat end of the hinge tube (where it butts up against a post) cause the tubing to close up around the hinge rod, just as a swedging tool does. I try to get at least 8 punch marks onto the edge of the hinge tube.

Usually, the hinge tube is now so tight that it doesn't move freely. Use your favorite method to correct this problem.

Turn the key over and repeat the process on the other end of the thinge tube
 
Groovekiller said:
OK, here is the old fashioned way to do this job. It may be in the old Erick Brand manual, I'm not sure.
......
Click to expand...

i actually have that right in front of me.

I prefer just to elongate the rod itself. It's actually faster than cutting out teflon circles and such anyways. But if one doesn't have the elongation tool (advanced swedging tool) then it doesn't help.

brand .. pg 22 is lengthening hinge tubing (when to short for swedging pliers)
though can't find your exmaple .. i'm sure it's in some book. I have about 10+ repair books floating around.
 
If this repair needs to be fast and cheap on a low cost clarinet, I would leave the key as it is and put a valentino pad in the key cup. The player of an instrument in this price range probably does not play well enough to be concerned with the key noise or feel of a sloppy key. The only problem then is making sure the pad seals each time it is closed even though there is some side to side movement. The valentino pad is very forgiving and stable in this type of situation if there is a reasonably level tonehole without gaps or chips in it.

By the way, I discovered an easy way to make hinge rods snug in their posts the other day while repadding a balanced action alto. Taking the keys off I noticed several of the hinge rods were slightly dovetailed on the slotted ends similar to the way needle springs are shaped to fit snugly in their posts. Suddenly it dawned on me that the tech who had previously worked on the sax had deliberately done this to remove slop in the key caused by wear in the post hole. Obviously the rod must be struck on the side so as not to close the slot.

I have found this technique to be less destructive than the old fashioned way of cutting the slot deeper and spreading the sides of the slot out. It usually takes just one light hammer blow to widen the rod enough to eliminate the movement. I have the music medic tool that "shrinks" the size of the hole in the post. It works very well, but unfortunately is too large to fit into some tight places like some palm key posts where the wear is often found.


John
 
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