Wood Filler For Seam Repair

John: NO!! If you do this, it will make the job of your luthier more difficult and exoensive. If you have to DIY, hide glue only.

 

As a luthier who has had to fix many cracks and other problems that were directly caused by using plastic wood to fill open seams, I urge you to keep that plastic wood as far away as possible from your bass. Regluing the seams (with hide glue) is considered a minor repair. Fixing the damage that can result from plastic wood in the seams often is not minor and can, in fact , get rather expensive.

 

Don't use the liquid hide glue, it won't hold. Use granualted hide glue two parts water with one part glue. Let it sit for awhile like this and then heat it to the melting point. You want it about as thick as half and half, so add a little water if necessary or let it cook off the extra water if it's too thin. It should be about 130 degrees. If you don't have granulated hide glue, go to the grocery and get some Knox Gelatin, it's a cousin of hide glue, and use it with the same formula as noted above.
Do you have clamps? How open is this seam ? Gluing up an open seem is not that expensive, so think about having your bass luthier do the job right the first time.

 

I'm looking at a bass top now that has been removed previously, with a fair amount of wood lost at the gluing surface, but rather than replacing the wood properly, someone has bogged it with some putty compound that is now crumbling away, taking more wood with it. The whole top now needs half-edging. yep, that's going to be expensive.

 

While Knox gelitan may be fine in a pinch, most professionals use flake or granulated hide glue.

Martin's suggestion that you take your bass to a luthier the first time is good advice. If you ask ahead of time, most luthiers will be happy have you watch (and ask questions) while they are doing the gluing and clamping. While it is not difficult to learn how to glue seams, it's easier to do it right if you have observed someone else doing it before you try it.

 

The hide glue from Upton's might be cheaper than the Knox?
But then there is shipping. You also have to clean out the old glue.
Clamps too? It's starting to sound like it'll be cheaper to take it somewhere. Even making your own clamps is expensive. How many do you need, how long is the opening. You want to clamp all of it with each clamp butting up against the next one; no spaces in between clamps.

 

I don't mean to step on any of the luthiers toes, but I have to say that, at least over here in Chicago, closing seams is maintenance and not really a repair. I find akin to changing your own strings and putting the bridge back in place when it starts to creep up or to the side. I do agree you should take it to a luthier the first time and have him show you. If he or she doesn't want to, find a different one.

I do see what your saying, but what about next time. Or the time after that. I went ahead and invested in clamps, a glue pot, a knife to spread the glue and an old toothbrush and have saved a bunch of cash but more importantly time away from my instrument. YMMV, IMHO, etc...

 

knox doesnt adhere to the wood well, im speaking from experience here, the gram strength is very low

 

While Knox would not be my first choice, it should be strong enough for gluing a seam together and is certainly better than any of the commonly available glues when hide glue can't be obtained. You don't need or want the strongest glue for seams on on a bass or any other violin family instrument. The glue in the seams should act like a safety valve and hopefully will release before a crack occurs in the wood around the seam.

I heard about Knox being used by musicians on the road back when I was getting started some 45+ years ago. I personally have never used Knox as a glue, but Martin Sheridan has been in the fiddle business for quite few years too and if he says Knox is good for this use, I believe him.