Veneer Shrinking

[christhegreat]

Hi there. I was suggested to use the Iron method to glue the veneer onto the guitar body. The veneer is flamed maple.

1) Spreaded titebond on both surfaces using a credit card to apply an even coat.

2) Waited a couple of hours till the glue is dried.

3) Used heat from an iron to glue the pieces together.

When I practiced on scrap, I didn't notice any shrinking, and the glue joint was solid, so I glued the veneer on the guitar. The problem is the veneer shrinked so much I have a gap of an eight of an inch between the two pieces.

I will remove the veneer, that's no problem. But I'd like to know if I did something wrong or if it is normal that the veneer shrinks a bit, and what could I do to orevent this from happening?

Thanks.

[rhoads56]

Hi there. I was suggested to use the Iron method to glue the veneer onto the guitar body. The veneer is flamed maple.

1) Spreaded titebond on both surfaces using a credit card to apply an even coat.

2) Waited a couple of hours till the glue is dried.

3) Used heat from an iron to glue the pieces together.

When I practiced on scrap, I didn't notice any shrinking, and the glue joint was solid, so I glued the veneer on the guitar. The problem is the veneer shrinked so much I have a gap of an eight of an inch between the two pieces.

I will remove the veneer, that's no problem. But I'd like to know if I did something wrong or if it is normal that the veneer shrinks a bit, and what could I do to orevent this from happening?

Thanks.

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What the????

Who advised you to use this method???

This is the most rediculous thing ive ever heard.

[christhegreat]

My, my, my. Testy and contentious! Well, it is a full moon outside.

Get out the sander and erase your mistake.

I do a lot of veneering. There is, as was posted above, no way to keep glue from popping through pores if you use too much and you have a pourous wood. Squigglygrained wood is almost always pourous.

The wrong glue will always cause trouble. I recommend white glue as the easiest most forgiving for the beginner. You can also get if off if there is squeeze out using acetone.

Polyurethane glue is good for stuff that gets wet a lot and not much else. This is just my opinion but I've tried it and had numerous aggravating problems with it in other applications. Naasty messy ooky foamy sticky goo.

Contact cement is great for Formica. It doesn't however give you a rigid enough glue line for wood veneer. It also reacts with solvent based finishes. The same pores that let the glue ooze out let the finish solvents ooze in. They can make the glue expand and bubble and you get big nasty blisters in the surface. Usually when you're halfway through the final clear coats.I've used it myself way in the past and have had numerous long term problems I've had to redo.

If you seal the veneer first you are goining to have trouble because the glue will cause the veener to expand on the contact side and the finsh side will not move as much. You may actually get some buckling. I know this sounds weird but believe me it can happen.

if you want a good "cheat" here goes. Roll a thin even coat of yellow glue(like Titebond) on both surfaces. Let it dry a couple of hours. Take a clothes iron and iron the two together. No I don't do this myself, 'cause I have a vacuum press, but a friend of mine built a Federal style sideboard out of crotch mahogany. This stuff is a bear to work with and he got beautiful flat results with not a speck of bleed through. It's sitting in his dining room today and looks great after ten years. My first reaction when he asked about doing this this way was "Say what??!?", but it does work. Especially on something no larger than a guitar body. Fine Woodworking had a article describing this techinque a couple of years later.

As a general glue comment, the guy I apprenticed with taught me to spread glue on both surfaces with a credit card. Squeegee it thin enough so that you can just see the wood through the glue. Any thicker and you're wasting glue and causing yourself trouble.. The drawback is that you have a very short open time. You need everything ready to go and a spare pair of hands, "read: experienced helper" when you are ready to go, and have done a dry run first to make sure everything is there and fits. This goes for all glue ups not just veenering.

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Here it is. It's the post #32 of topic Veneer problem.

[rhoads56]

Well, i would never do it like that, its just asking for trouble...

[Drak]

If you need any step by step help, feel free to PM me. I have done at least 15 iron-on veneer jobs, and even tho I recommend against using this method, I'll help you any way I can if you want to go this route.

[tirapop]

Iron veneering as seen in Fine Woodworking Magazine.

So, you were trying to veneer to separate pieces of veneer to a body? I don't know if veneer tape would work with the iron, to hold the pieces together.

[Drak]

Nope, not recommended.

You're supposed to overlap the second piece over the first by a very very little bit.

There is a trick where you take a pencil and place it under the second piece, iron down a section, then remove the pencil, that is to give you the wee bit of excess you need for the inevitable shrinkage.

Or, if you have a good eye and control, you can do without the pencil trick and just overlap it a bit. If there's any extra that didn't shrink back to conform to the join, you just sand it off since it will sit a bit proud of the rest.

But as I said before, I don't like the iron-on method much anymore, and the way I do it now, which results in much better adhesion, does indeed involve veneer taping the two pieces together beforehand, but no irons.

[rhoads56]

Iron veneering as seen in Fine Woodworking Magazine.

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By all means, continue to do it using this flawed method then.