1. Barrel gets stuck: Humidity can enter the wood and increase the diameter of the tenon. This can cause problems, because the connection between the joint becomes too tight. It makes it hard or even impossible to assemble the parts or to take them apart.
The solutions are:
a. Hold the barrel very tight in your hand, and instead of trying to turn the barrel, wiggle it upwards.
b. Bend the barrel in all four directions, like you would like to break it off. Don't try it too hard and not on Greenline instruments! Greenline tenons can break! .
c. Lay a leather belt around the barrel in a sling and try to turn it.
d. Just wait a day or two and have the instrument dry by itself. Keep it in a dry environment.
2. Barrel wobbles If the Barrel wobbles, wind some thread, some tape or paper around the top-joint tenon before you push on the barrel.
If a barrel cracks at the tenon receivers, the crack might be caused by physical force. Be careful because the wood is very thin up there. Don't tilt the different parts. Just turn or push them in straight.
If a crack goes all the way into the bore, humidity would have caused it. It can nicely be glued, and the barrel will be fine again. As an emergency solution, put some tape around the barrel to make it seal again. Do not use oil or grease on the crack, which would make it impossible to glue afterward.
4. Loose sockets Low humidity makes the wood shrink. Metal tenons can become loose when the glue loses its hold. If the metal receiver was glued on with a Thermo glue or shellac, the metal tenon just needs to be heated up with a torch. If in doubt, ask an experienced repairman to do it for you.
5. Barrel versus tuning rings
To change the length of an instrument with only a barrel will have its biggest effect on the notes closest to the barrel. A better solution might be to combine it with some tuning rings between the top and lower joint. This way, the instrument can be prolonged just a bit at the barrel and some more at the lower-joint. A more even tuning will be possible.
6. Zoom barrels
If you turn a zoom barrel too far apart, you might not get it to work again. Don't use force but give it to someone who knows how to handle it.
7. The original barrel The original barrel was reamed together with the top-joint of the instrument when it was built. Therefore, there is a good chance that it will have a very good and smooth connection to the top-joint in the beginning. Over time both joints might develop differently, and the bores of both joints might become oval. In some cases, this might cause problems. Try to turn the barrel in different positions and see if it improves its performance. If so, just remember the position and keep it that way. There is no reason to exchange the barrel just because of this.
8. The cork is too thick New instruments or joints might have a cork, which is too thick to go on smoothly. First, make sure that it is the cork and not the wood that is causing the problem. If the cork is too thick, grind it down with 240-grain sandpaper. Apply some cork-grease before you put the joints together.
9.The tenons cannot get all the way in
When the barrel can be pushed over the cork but not any further, the tenons wood is swollen. Take a thin strip of sandpaper or fold a piece of sandpaper to make it more stable and remove a layer of wood of the tenon just above the cork. Do it carefully. Continue to sand just these areas down until you have the fit you like.
10. The cork is loose
Lately, many tenon corks on new instruments become loose. If you can remove the cork gently in one piece, do so. Clean the loose cork surface with alcohol or gasoline and apply a thin layer of contact cement on the wood and the cork. Wait a few minutes until it feels dry and then press it tightly back into place. If only one end is loose, clean only this bit on the cork and wood, apply the contact cement, wait and press it into place.
Selecting barrels Read more