Oh Noes, Another Veneer Question

[joshua]

Hello again, helpful speaker builders and fellow hobbyists. I'm putting together some smallish speakers (desk PC projects) for gifts this year for Christmas. I'd like to finish them in some exotic woods and nicer burls that I have seen out there. Now, I have used the BandIt paperbacked veneers for many projects. I have never run into any issues with that product, and it typically works out great for my purposes.

My question applies to some of the smaller sized 1/42" veneers that I have seen advertised on eBay and elsewhere. I have found some great prices on smallish pieces, but I don't know much about the difference in applying it vs the traditional speaker medium, paperbacked veneer.

Anyone have any advice? I don't have access to any kind of vacuum press or anything, I just want to know if I can apply it with contact cement like I have in the past with the paperbacked veneer.

Thoughts?

[bobbarkto]

Re: Oh Noes, Another Veneer Question

Contact cement isn't realy a good choice for unbacked veneer, but it might work on a very small box.
It tends to creep and bubble over time. Sunlight can do very bad things to it.

Do you have some clamps?
You can use regular wood glue, waxed paper and some mdf plattens and slightly curved wood cauls to press the veneer to each face.
A very small box might only need half a dozen clamps.
It's pretty easy to do on small items.

[WWWJD]

Re: Oh Noes, Another Veneer Question

I've been using Bill's PVA / Iron method on paper-backed and raw with outstanding results.

http://oak.cats.ohiou.edu/~schneidw/audio/veneering.html

Veneering right now as a matter of fact; waiting on a couple pieces to dry up prior to ironing.

[Adam_M]

Re: Oh Noes, Another Veneer Question

I've used contact cement on some larger speakers with unbacked veneer, and while it works its a real pain. I've only been able to get solvent based contact cement to work, which smells awful and isn't very good to breathe for a long time. I always ended up with at least 1 bubble on every side too, which I'd stick back down using super glue by cutting the bubble along the grain and putting some glue in and pressing until it re-stuck. I always seal with shellac after to make sure that any oil-based finish don't seep through the veneer or any small voids in the veneer and cause the veneer to lift.

I've had luck with Iron on, as long as you are careful not to scorch the veneer.

I've used clamps and thick cauls to cold press veneer on small cabinets only. I don't think I could get enough clamping pressure on a larger cabinet.

After trying all of those methods (which admittedly worked...) I just bit the bullet and got a vacuum press and never looked back.

As long as you are careful (about the heat of the iron, clamping pressure, contact cement fumes, whatever else can happen) any of the methods above will work.

-Adam

[mgrabow]

Re: Oh Noes, Another Veneer Question

Iron on will work very very well for raw veneer. However cover all the edges with blue painters tape and cover it actoss the grain about every inch or so, It will tame splitting.

[joshua]

Re: Oh Noes, Another Veneer Question

Thanks, I think I'll try the iron on method described above.

[bobbarkto]

Re: Oh Noes, Another Veneer Question

Good luck!
I've found it very troublesome with raw/unbacked veneer.
Never could predict when splits would occur but they almost always will.
No technique I tried would solve the issue completely. Including taping, extended post glue drying, pre-heating, careful moisture measurement, and so on. Sometimes the veneer will just split, usually as it cools.

Best results I obtained:
Let the glued veneer and substrate dry as long as possible before ironing (keep inside the manufacturers window for application).
Start ironing in the center of the panel and work slowly out toward the edges.
Use as cool an iron as possible that still alows for a good bond.

Thanks, I think I'll try the iron on method described above.

[weinstro]

Re: Oh Noes, Another Veneer Question

Thanks, I think I'll try the iron on method described above.

In my experience, I had rather mixed results with the iron on method. Basic problem was edges and corners not sticking well. Very annoying when discovered by the router. In fact, I'd rather stick pins in my nose than give this method another go.

I found that cold pressing with plain old Tite-Bond was better, especially at the edges. A couple of factors:
- make sure your substrate (MDF or plywood) is flat
- evenly apply glue with a roller to both veneer and surface
- sandwich with a couple of pieces of MDF, which act as cauls to distribute the clamping force
- apply clamps liberally
- tape where you want to be sure glue doesn't go, e.g., another veneered surface

Note: I did not try this with unbacked veneer, so maybe try this on a test piece, first. I found "joewoodworker.com" to have reasonable advice.

Regards,

Rob

[s7horton]

Re: Oh Noes, Another Veneer Question

count me as another who doesn't advise ironing on raw veneer. It may work sometimes, other times not. You never know when cracks and splitting will show up. Could be during application, or could be a year later (I've had both). Applying heat to an unstable product that rapidly releases moisture is asking for trouble in my opinion.

I've tried it many times, with many different variations and all failed. I finally took the plunge and picked up a vacuum bag. And then a second vacuum bag. I didn't want to spend the money, but at least I know what my results will be now. I've also made the move to a PPR glue to give me a rigid glue line. So far I've been satisfied.