Maxofff
A problem of this kind, I got a 2007 sonor, and here is such a crack in the cladding .. there is no Caudle crack inside the drum, only this one, why could there be such a problem? did the former owner pull the layers strongly or something like that? and could that translate into a serious drum problem? thanks in advance)

runner
This happens when the instrument is stored at a point without heating. In any case, in a room where temperature and humidity are constantly walking.
During the day one humidity / temperature, another at night. I generally keep quiet about the off-season. (Judging by the rust, it was.)
Maxofff
I also suspect ... what to do with the Caudle, tell me, is this a strong marriage, so to speak?
runner
good is not enough.
It is necessary to check the integrity of the remaining layers. If they are not damaged, then only the top layer of veneer probably burst, because. it is the thinnest. If only it swelled, then it is not so scary.
But this is still bad, because the kadlo was under stress from tension and from moisture it could deform.
We must give it to the master for verification. I think that the damaged veneer layer can be replaced.
Maxofff
in short, you need to remove the lags, then the cladding and repair the barrel ... by the way, I haven't removed the cladding from it yet, is it strongly glued there?
runner
it is veneer, not plastic wrap. You can't take it off like that. You will only spoil the instrument. It is also not a fact that it is damaged. With this only to the master.
Maxofff
it turns out it's not just a blue lining, but the first layer of the drum? there are no such masters in my city ..
runner
remove the top layer. (Judging by the photo, the crack reached the end of the cladding)
scorp
Does the crack go from top to bottom? It is very similar not to a crack at all, but to a factory seam, under varnish.
Maxofff
goes from top to bottom so oblique but the lines themselves do not go left to right clearly at an angle. There is no gluing inside the frame opposite.
scorp
well, is it flat? Not zigzag? I played for a year on the mapex m installation, there was an oblique gluing on the small one, visually, at the same angle. Try to look for detailed photos of such a drum, perhaps it should be so. There was no seam inside the mapax either)
the varnish itself is not cracked?
insider
this is the joint of the top veneer layer
Maxofff
Comrades, we figured it out, this is really a joint, another person has the same line on the drum. Thank you all friends!