Veneer Waved After Being Glued

[christhegreat]

Hi. I glued a flamed maple veneer on a basswood body using titebond.

After the glue cured, I noticed the veneer was waving a bit at some spots. I'd like to know what I could do to help it. I already tried using a cloths iron but it didn't really help.

Will I have to sand back and redo the job? And when I'll glue the veneer how can I make sure it won't be waving like it did?

thanks.

Edited July 31, 2005 by christhegreat

[Drak]

If you dig under the waving, you will either find a big ole' wet glue blob sitting under there, or a very dry glue-starved area. Either is not a good thing.

Next time, use a solid glueboard, like 1/2" Paduak or Maple, the same shape as your body, about 1/2" bigger all the way around next time (didn't I already say that tho previously?).

And practice on scrap about 3-4 times next time before even approaching your real guitar body.

If you don't have the patience and/or extra veneer to practice on scrap, you will continue to experience these veneering problems on the guitar until you have enough pain to make you practice on scrap first and gain some success, THEN approach the guitar.

If you continue to treat your guitar as your test ground for veneering, then be prepared to scrap the guitar sooner or later, because you are treating it as nothing more than a testing ground, and thusly, treating it like crap. You're not supposed to even approach the real guitar until you have successfully done the job in question a few times on scrap and know what to expect in advance. If you are experimenting on the guitar itself, you have made the guitar expendable, just like a piece of scrapwood would be.

[rhoads56]

+1 for Drak.

Go and buy a book on Veneering. $20, if that... i dare say a lot less than what you have spent on veneer that hasnt worked.... three times now? You're wasting your own, AND our time by experimenting when you have absolutely no idea what your doing.

[jamesj]

Hey Drak, Im going to be using a 1/4" thick top, I have never "veneered" but I have glued lots of wood, Never a Maple Top, like my next project. My question is do I need a bigger peice to lay over it? At its thickness I was going to just use 1X2s Three places along the 16" tall X 11.25" wide body, That is what I have done with 1x12 oak on spruce to make 2xs for show tables (at work). I can cut out 3/4 partical board if needed.....

[erikbojerik]

James, I did exactly what you're proposing to do, on a 17" wide doubleneck body no less. I did not use a full-body clamping caul. Came out fine.

I also tried veneering long ago...did exactly the same thing, used the guitar body as my proving ground. Same mistakes. I proved that I hated veneer and vowed to always go with a drop top.

[Drak]

I heard a neat veneering story yesterday.

I was at my local wood guy's place having some work done to some tops, and as always, I stop to chat it up a bit when I'm ready to leave, he is a walking encyclopedia of wood knowledge and is a great storyteller too.

So he got some new veneer in and the conversation turns to veneer and veneering, and he told me an interesting fact:

That back in the 1800's, when all the kick-ass furniture that is worth thousands of dollars today was being made, that most of the really high quality furniture was veneered, and also, that almost 100% of the time, the furniture makers, the guys who had 20-30-40-50 years in the furniture business and could build you anything you could imagine (for the times anyway), the guys who could build the fancy scroll-top desks and the tables with the fancy lion-paw legs and ALL that stuff by hand....

...Never veneered their own furniture, they always sent the job out to the veneering guys to do it.

Now, if someone with 40 years in the furniture making business didn't/wouldn't do their own veneer jobs and left it to the veneer professionals, that kinda tells you something, doesn't it?

I will say that you have gone at it 2 or 3 times now and do not seem in the mood to give up yet, so good on you for that, that's the kind of stay-at-it spirit you need for learning veneering.

Anyway, on to answering your questions....

I noticed the veneer was waving a bit at some spots. I'd like to know what I could do to help it. I already tried using a cloths iron but it didn't really help.

Will I have to sand back and redo the job? And when I'll glue the veneer how can I make sure it won't be waving like it did?

It depends on why the veneer is waving as to what will cure it. Is this the same veneer you ironed on? If so, then when you say waving, I'm taking it you mean 'bubbles' of veneer that didn't iron down properly?

A lot of the answer depends on how you did the veneer in the first place, so I need to know how you applied it to give you the right answer.

[christhegreat]

Actually I removed the ironed veneer. I practiced glueing on scrap and everything came out perfect, I suppose because I used small testing surfaces. This time I used the weight bag method like on the tutorial on the project guitar site.

I spreaded titebond on both the guitar and the veneer, a nice coat, nbut enough so that I always see the wood through the glue, and taped the veneer along the centerline, then placed the weight bag (30Kg) on the guitar, making sure the weight was equally distributed.

And yes I'm determined to get the veneering job done. For the finishing job I already got the color and depth I wanted with the stain. I'm only having trouble with glueing the veneer correctly to the body.

But you're all great help, and I'll go get a book on veneering to avoid some silly mistakes I could make again.

thanks.

[Drak]

OK, then I'm going to guess what you have are either waves from inconsistent weight distribution, or waves from too much glue trapped under the veneer.

I know about the sand bag thing, and I think Brian did that tut, and I know Brian knows what he's doing, but in my experience, you really need the hardwood glueboard and about 15-20 clamps if you want a really superior, truly-dead-flat-and-glued-right veneer top.

At least that's what my own personal experience has taught me.

You could try taking a pinhead and popping a tiny tiny hole in one of the waves, then press on it hard, and see if you get glue trying to ooze out of the hole. If so, you have excessive glue trapped underneath the veneer.

Sometimes, you can slightly wet the affected area, take some scrap wood and clamp down on these spots, and if the glue is still moist at all, sometimes it will just glue itself down. IF you're lucky.

So to fix the problem, you need to figure out exactly what the problem is first, either the sandbag didn't have enough weight to really get everything flat (which is my guess) and it didn't squeeze out all the excessive glue, or it just didn't press everything down firmly and parts of the veneer just didn't bond to the wood.

I don't know how many bad areas you have so I don't know if it's worth chasing them down and trying to fix them or not. If it's just one or two really small areas, maybe worth it to try and fix. If it's a lot of areas, probably best to take it all back off and try it again.

With unthinned Titebond applied to both surfaces and nothing but a sandbag to press it down, you probably didn't get all the glue squeezed out, that would be my guess.

Next time, try to find some 3/4" regular Maple (it should be pretty cheap really), cut out a glueboard about 1/4" bigger all around than the actual body, have some wax paper (goes between the veneer and glueboard, you can even tape it to the glueboard if you want) and a lot of clamps ready, and apply the glue about as thin as you can get it on. Use one of those white plastic spatulas from Home Depot (.50 cents) to spread it out and scrape off any excessive glue before you commit to clamping. You really need to keep the glue to a minimum with veneer. With unthinned titebond, you could probably get away with just applying it to the body itself and that's it, but I do like to apply glue to both surfaces, but I thin my titebond with water a little beforehand.

[christhegreat]

Ok. I checked again the veneer. It rested a couple of days. I tried to poke it with a pinhead, but no glue came out. I noticed the waving is only detectable when touching the surface, and looking at a certain angle. The waving is less than 1mm thick, and feels very hard, like there was too much glue under that part.

I'd like to know if by sanding down flat I could achieve a good result.

Also what's the ratio you use to dilute the titebond with water?

The good thing is that I work in a hardware store so I'll get the clamps I need pretty soon at discount. I just thought I didn't need them since the tutorial seemed so easy to do. If there's no way to save the job, I'll grab my sander and do it again using clamps and a board this time.

thanks.

Edited August 1, 2005 by christhegreat

[Drak]

Then I would just chalk it up to the sandbag just not being a dead-flat device, but apparently it worked pretty well.

Well, yes, you can sand down small imperfections. Veneer is thicker than a lot of people think, and you can do quite a bit of sanding before you sand thru it normally.

The problem is that if those areas aren't glued down properly, once you start to apply any kind of finish, they might become problematic later on, they might 'pop up' on you.

But, what the hell, you have nothing to lose, I'd just sand them flat and see how it goes from there first.

Hmmm, no particular ratio, I just add water until it becomes the consistency I'm looking for, somewhere around thick cream. It's not a lot of water really, just enough to cut it down and make it 'paintable', so I can apply it with a paintbrush if I want, which I do sometimes.

My 'test' for veneer application is to rap on the bare wood with my knuckle and make a mental note of the sound. When veneer is applied really good, the sound will not change at all, it will sound like there's not even any veneer on it. Veneer that wasn't applied really tight, when you rap on it, it will sound sort of mushy, and have sort of a papery sound to it.

Another thing I do is once it's applied and dry, I rap all over the top with a fingernail trying to pick up any areas that didn't get glued down, they will also sound sort of like paper, or sort of hollow, you can hear the difference when you hit an area like that, hopefully you don't hear any at all. If you do, those areas will probably 'lift' on you once you start applying a finish to it, then it really sucks.

[christhegreat]

Great. I knocked on the wood and checked every little spot on the guitar and everything came out great, glued tight. I just hope I won't run against other problems. thanks again