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Hi all,

I finished a neck through bass in september. The neck is eastern maple and bubinga, 7 pieces. Recently I noticed a slight ridge in the finish that runs along the maple/mahogany wing joint. Obviously the maple has moved causing the line in the finish.

This maple had sat around the shop for about a year so it is well seasoned. Is it that the glue joint wasn't good? I used tight bond on that joint.

Has this happened to anyone else?

I want to continue building neck throughs with maple but how to deal with it moving? If I let it sit for a year and its still not dried out enough.

I don't know how I could take the risk of selling a maple neck to a customer if the thing is going to crack apart.

Any advice much appreciated.

Stefan

Im trying to picture this. The maple is flanked on one side by mahogany and the other side by babinga the seam is raised at the mahogany/maple joint and not at the bubinga/maple joint?

If this is the case I would suspect the mahogany not the maple.

you visualized it right.

I've heard that maple is prone to moving. this is why i suspected the maple. The mahogany has also been in the shop for about a year.

If the maple had moved I would expect to see a change at both joints. mahogany will swell much more tha maple. If the maple is seasoned it is among the most stable woods. this is wy it is used for bench tops. If it is still green then yes will move on you. While because I can't see what is happening I can't say for sure what is going on but I some real doubt the maple moved on you.

What finish did you use? I ask because I've heard of titebond glue lines showing over time under waterborne finishes.

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That could be it, I used ktm9 which is a water based finish.

It's only showing over one small part of one joint, and you can feel the edge with your finger. This is why I think something has moved.

Thanks,

Stefan

Could the maple have stayed the same and the mahogany moved?
I have seen more movement in mahogany than hard maple many many times.

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How long is that in luthyears?

Which of the many versions of Titebond did you use?

There is a known issue using ktm with titebond, and the appearence of visible glue lines. From the KTM listing on LMII:

This has happened to me on my Alembic 5-string bass with polyester finish. Take a look at this discussion at the Alembic website:
http://alembic.com/club/messages/393/58 ... 1229952424[url]

Thanks for all your replies.

By the looks of that link it seems this is a fairly common phenomenon.

BTW I used the original version of tightbond.