Veneering tips please...

[Ryan Sparreboom]

I am going to be trying veneering for the first time for some cabinet doors. The frames are cherry and I want to use walnut burl veneer for the panels. They will be about 14" by 26" and I planned on 1/4" MDF for the substrate. I plan on a 4 way bookmatch for each panel, with both sides of the panel being done. I will use Titebond 3 and apply it to the substrate with a roller, then stick on the veneer, cover it with wax paper and clamp it between pieces of 3/4" ply or MDF with tight clamoing pressure and leave it over night.

I hope my plan sounds O.K. I have not done any veneering before but from all the reading I've done this seems to me it'll work.

Any tips or suggestions for me?

Thanks.

Ryan

[Brent Smith]

Hi Ryan,

In general your proposed method is OK. I would use cauls to evenly distribute the pressure on your piece. Your choice of glue might be a problem. Walnut burl, most burls for that matter, tend to glue bleed through. Cleanup becomes a concern at this point. If not too bad, a card scraper should do the trick. You may have better results using a cold press glue though. You can usually find it at any good woodworking store or online, Joewoodworker has a good one. Another thing, which you didn't mention, is to roll the veneer on from the center out to prevent bubbles or non adhesion in your work.

[Ryan Sparreboom]

Thanks Brent. I'm not familiar with cold press glues. Can you mention a brand I could look for locally?
The glue squeezing thru the veneer to the face is definitely a concern.
And thanks for the tip to roll the veneer out from the middle, I forgot about that but had read it.
Thanks.

[Mike K Wenzloff]

A consideration.

Layout your veneers in the pattern desired, with the face of the veneer that will be seen face up. Tape the veneers very well together at the seems. Though I often use veneer tape, I also have used the blue painter's tape.

The problem you may well encounter just sticking the veneer down on the substrate when it isn't a continuous piece is the pattern pieces may well shift during the addition of the platen (the second layer of MDF or ply) and cauls (which I also recommend). In fact, a couple layers of ply or MDF for the platen along with cauls is a good idea.

In general I avoid using PVA glues with veneer, prefering hide, PRG or epoxy. Bleed through is more of a problem the thinner the veneer for any given species. The most readily available cold press glue is made by Titebond. It is simply called Cold Press glue on the jugs.

Take care, Mike

[Jim Becker]

Ryan, you can get cold press glue from Joe Woodworker (http://www.joewoodworker.com)

Make sure that you use cauls to evenly distribute the pressure across your platens when you clamp things together.

[Dennis Peacock]

I agree with Mike....use Hide Glue or Liquid Hide Glue for your veneering. PVA glue can cause more problems and veneer slip than you care to fuss over. Also, I'd recommend setting up a venturi vacuum pump (operates off your compressor) and a 2' by 4' vacuum bag. I did this last year and it works GREAT!!!!. With this setup, you can put a cabinet door in the press, turn it on, and then once it's in place you can toss an electric blankey on top (set on low heat) to help the glue set better in cool to cold shop temps. Then after 4 hours of set time you can take the door out of the press and do another one. I wish you great success and please post pics of your progress. I'd like to see your work and how well it goes for ya. :)

[Mike Henderson]

Before you do any veneering with some expensive burl veneer, I'd recommend you do a trial with some inexpensive veneer. And even then you'll have more problems with the burl. Burls tend to warp when they get wet and most of the glues mentioned are water based.

Mike

[Steve Rozmiarek]

Ryan, burl veneer in particular can look a lot like a crinkle cut potato chip when you get it. It may need flattened, which is easy and crucial. The before mentioned glue link for Joe Woodworker sells a fantastic product that I highly recommend, but can't remember the name for. I also second the cold press glue. If possible, skip the clamps and just get a vacuum press as well. You will not be sorry.

[David DeCristoforo]

I veneered panels like that for many years until I got a vacuum press. Use plenty of clamps (no more that six inches apart with 3/4" cauls). Mike's suggestion to do a "practice run" is solid. You don't need any "fancy" glue. Plain old white glue (Elmer's) will work fine and give you plenty of working time. Once the veneer is laid down on the glued surface, get your cauls down as quickly as possible to keep the veneer from curling. Do it once and you will have a much better idea of how....

[Brent Smith]

Thanks Brent. I'm not familiar with cold press glues. Can you mention a brand I could look for locally?
Thanks.

Hey Ryan,

As Mike mentioned, Titebond makes a cold press glue, but it would really be worth your while to take the extra week and order it from JoeWoodworker. I've had much better results using his than using the titebond product (it might have something to do with shelf life- no where I've bought the TB cold press has admited to great turnover of the product).

[Brad Shipton]

For a first project, a burl is not a great place to start. A burl very well may sour you to the veneering process. They are brittle, tend to have far more flaws that require attention and just generally take far more work in all steps of the process.

Maybe you can find a pre-flattened Burl, but I have always dealt with Certainly wood and have never found pre-flattened burls or crotch veneers. I suspect you will need to flatten with either Super Soft 2 (Joe's) or GF20 to flatten the stock. I have used both and they are pretty much the same thing. Flattening the stock is easier with a vac bag, but it will not take that much weight for your project scope. I have found the best results cutting the stock very shortly after it has been sufficiently dried. Flattening is about a two day process. One day to apply and start the drying and the better part of the next to finish drying. As you dry the stock, you will need to change the paper towels (newsprint used by some) a few times.

As to the adhesive, most professionals do not suggest anything other than Urea Formaldehyde for a burl. I use Unibond 800. You need a rigid glue line, and PVA's do not offer this. Burls and crotch veneers are very fragile, crack and split/crack very easily. Long term a PVA is risky with a Burl.

Another thing not mentioned is the use of a cross banded backer. There was a recent discussion of this topic on the Woodweb and it was recommended to me that one should always cross band a Burl or Crotch before applying to the substrate. This came from seasoned production fellows with tons of experience.

Veneer systems and Vacupress are both great supplier of tapes, adhesives and lots of other veneer tools. Joe has great service too.

Good luck.

[Brent Smith]

Another thing not mentioned is the use of a cross banded backer. There was a recent discussion of this topic on the Woodweb and it was recommended to me that one should always cross band a Burl or Crotch before applying to the substrate. This came from seasoned production fellows with tons of experience.


Hi Brad,

It's funny you should bring this up. The two times I tried cross banding with burl I ended up with more problems than cures. I'll have to check your reference and see where I went wrong.

[Brad Shipton]

Brent, what problem did you have? I tried end matching two panels after cross banding once and wow did that ever turn out to be a nightmare. Far too much time between coming out of the bag and going back in onto the sub. Here is a pic of what happened to an end cut. It was nowhere near that bad before I got the layup all back into the bag, but it was a struggle and I did end up with a couple small wrinkles. Now I make darn sure I get it back into the bag quickly and it works much better.


http://i272.photobucket.com/albums/jj176/Brad805/Crotch%20Veneer/DSC01840.jpg

[Brent Smith]

Hi Brad,

That's about the same problem I had, but with Elm Burl. It didn't just curl and twist on me, it pretty much tore apart the veneer. The first time I tried it, I was just veneering a single panel for a jewellerie box top, and I think I didn't get all the moisture out of the burl after flattening it (teach me not to rush Mother Nature!!). The second time, I was doing a 4 point bookmatch and the original pieces came out perfectly flat (or at least as close as you'll get). I got the 2 halfs back under the press pretty quickly and they came out not bad. Then, if I remember correctly I left it for a few hours before doing the final layup on my substrate and I ended up with something similar to your pic. Next time I'll try getting it back in the press, or bag, much quicker. I talked to a guy that's been in the veneer business for decades here in town and he told me that after crossbanding it's a good idea to move quick. I've done plenty of other burls straight onto a substrate, usually BB Ply, with no problems.

[Chris Padilla]

What is this crossbanding you guys are referring to?

[Brent Smith]

Hi Chris,

No expert on it here, as previously stated my attempts at using it were disasters, but here's how it was explained to me by someone who has been veneering for longer than I've been alive.

Crossbanding veneer is just a way to stabilize a glue up and protect it from either grain, or joints in the case of solid woods, from the substrate telegraphing through or in the case of burls making them easier to work with without causing damage to them. Usually a quarter sawn veneer is used as the crossband. My buddy said Mahogany is one of the best as it is a very stable wood once dried. The two times I tried it I used quarter sawn white oak veneer as my crossband...it was what I had lying around. Think of it as an all wood alternative to paper backed veneer.

I can see the advantage when using burl or crotch wood veneers and needing to match two or more pieces, but with regular veneers I'm a bit skeptical about it's advantages. I just finished laying up a few panels with Crotch on BB Ply and didn't use any backing. No bad results from that, or from any other veneering I've done without crossbanding.

[Chris Padilla]

Thanks, Brent. That was my guess. I'll be resawing some (nothing special) walnut planks very soon and veneering a double-sandwich of 5/8" MDF (i.e. 1 1/4" MDF). I have read the opinions of several "experts" that MDF can hardly be beat for a substrate: no grain, smooth, stable, etc. Should be fun...I'll have a thread going for it.... :)

[Brad Shipton]

First off, sorry to all about the pic size. UGGH.

Personally, I have mixed feelings about the benefit of cross banding (secondary backer veneer with grain 90deg to face). I understand if one were using the historically correct glues or substrates less stable than MDF, but if you use Urea Formaldehyde I am not totally convinced. The fellow I chatted with routinely bids supply projects up to and above 4,000sq ft, so i opted to give him the benefit of the doubt.

Brad

[Steve Rozmiarek]

First off, sorry to all about the pic size. UGGH.

Personally, I have mixed feelings about the benefit of cross banding (secondary backer veneer with grain 90deg to face). I understand if one were using the historically correct glues or substrates less stable than MDF, but if you use Urea Formaldehyde I am not totally convinced. The fellow I chatted with routinely bids supply projects up to and above 4,000sq ft, so i opted to give him the benefit of the doubt.

Brad

Seems to me that crossbanding is a useful tecnique for veneering over solid wood, but what is the advantage if you are veneering a manufactured, and more dimensionally stable, substrate? Everyone has seen an old piece of furniture with cracked veneer from the expansion/contraction of the substrate, and if I'm correct, crossbanding is an attempt to mitigate this? I've never used it personally, and to date, no disasters.