Veneer stained after glueing

[Robert Engel]

346154Alright I'm depending on the great guys at SMC to tell me what's happened.
This is my first attempt at veneering a large piece like this.

One of the drawers fronts I veneered has these dark linear streaks that look like staining.

Needless to say, a real bummer.

The veneer is glued to solid wood with Titebond Cold Press glue.

Thinking about it, I really think I used too much glue and the veneer soaked it up. I also noticed the glue dries very dark.
I'm thinking some glue bled through some porous grain in the wood. Is there something I should do to avoid this?

So aside from what is going on here, my other question is do you apply glue to both veneer and substrate?

I used a rubber glue roller, which I think leaves a thicker film then needed.
In a video I saw yesterday, I noticed the guy used a fabric roller.

I'm going to have to plane off the veneer and apply some new - worst of all, pray they still have some from the same lot.

[Jamie Buxton]

Hard to tel what happened from the photo. But before you plan it off, try just sanding. You might have just surface coloration from bleed-through. If it turns out that the discoloration is through and through, you can just continue on to the planing solution.

[Kevin Jenness]

Did you sand this piece yet? That sure looks like an incipient sand-through where the veneer is so thin that it is translucent.

The lines parallel to the grain are very odd I have never seen a staining problem like that with Cold Press adhesive, but there is a first time for everything. If the other pieces came out ok, what is different about this one? As Jamie suggests, try sanding it out.

Glue thickness should be in the 4-8 mil range, on the substrate only. Applying glue to raw veneer makes it curl and hard to apply. Test panels are always a good idea when using a new process or veneer to check for adhesion and bleedthrough. A painters mil gauge can be helpful. You can control the application by using a toothed trowel followed up with a non-absorbent roller.

[Tony Joyce]

So aside from what is going on here, my other question is do you apply glue to both veneer and substrate?

I used a rubber glue roller, which I think leaves a thicker film then needed.
In a video I saw yesterday, I noticed the guy used a fabric roller.

I'm going to have to plane off the veneer and apply some new - worst of all, pray they still have some from the same lot.

Put glue on the substrate only. A rubber roller should work fine. Use a glue that is lighter color(Joe Woodworker). The glue film should look like a light coat of paint, you should see the grain/substrate through it.

Tony

[John Blazy]

Was your clamping caul steel? If so, then the steel reacts with the acetic acid in the glue which becomes Ferric Acetate - the classic ebonizing solution for blackening wood that has tannic acids in them. You often see this when pipe / bar clamps contact the squeeze out of regular wood glue during edge gluing - the three ingredients - Fe, vineger and tannic acids create very dark spots.

Even steel wool particles or steel grinding dust on the veneer will react with the glue and wood to create uneven dark lines.

[John T Barker]

I think this is mentioned above; I see what appears to be the result of the veneer going through a sander. The dark lines are such that you can connect them with a ruler. If a thin spot in the veneer has allowed the glue to come through is there any chance for a repair? Removing the glue and replacing as if doing an inlay might not show.

[Wayne Lomman]

Looks like a substandard veneer. If your technique was wrong you would have the problem everywhere, so go kick something else, not yourself. Hope like hell you can get another piece. Cheers