regluing veneer to a timber surface

[David N]

I have just stripped an old walnut burl veneer off a small table top and intend to apply another burl veneer to the top. I have sanded the top reasonably flat but there is still a low spot on the top. What is the best filler to use to level the top that will adhere to the table and be able to take a glue on veneer? What is the best glue to use as I intend to iron on the veneer?

[woodPixel]

How low is low?

I would add a veneer patch in the low spot. Just glue it down then sand it all flat, feathering the edges. Use a known flat edge to check its all good. If it is deeper than 0.6mm, use a piece of real wood and do the same. If still too low, add another and repeat.

Once its all flat, then add the real veneer topping.

Any photos?

[David N]

The low spot would be approx 2 to 3mm deep and about 300mm long with the lowest area in the middle of the trough. I think your suggestion of building up the depression with veneer is a better option than filler.

[ian]

to add to Woodpixel's post

I'd insert a piece of solid wood (or thick veneer) into the depression.
I'd then plane and sand the top flat and apply a sacrificial veneer over the whole top.
Sand this sacrificial veneer completely flat, then apply the show veneer.
I'm suggesting this as a way to minimise the possibility of the patch telegraphing through the new show veneer.

Depending on what is on the underside of the top, it might also need an extra layer of veneer.

[Xanthorrhoeas]

When you say "iron on veneer" are you referring to the pre-glued veneer sheets? Long, long ago in my infancy (woodworkwise) I tried some Australian cedar veneer that was pre-glued/iron on. It was not good and did not give a good result. In my experience in the years since I have found that an unglued veneer can easily be laid on using hide glue (even the ready made Titebond liquid hide glue) with much better chance of success. Hide glue is delightfully reversible with hot water if you stuff-up too.

However, I do admit that I have not even looked at pre-glued veneers for many years so I may be unfairly maligning them. This is just a word of caution to do at least some practice with the stuff first on something non-critical as (from bitter experience) the iron-on adhesive is a blighter to remove if the process goes awry.

David

[David N]

No I'm not using pre-glued veneer, I intend to use Titebond, applying a number of coats to both surfaces, letting these coats dry, and then iron the veneer to the top. I think this should work ok. Do you think a vacuum press would be a better alternative?

[Xanthorrhoeas]

Well, that's a technique that I have not used. I suppose you have seen somewhere that it works? I would not have expected it to as PVA adhesives are not reversible AFAIK.

If I am veneering new boards for the bases of new boxes etc. I use Purbond polyurethane (it is low-foam polyurethane) and a vacuum press (a cheap one with a hand pump - system designed for skateboards. Using plastic freezer sheets around the work stops the adhesive from sticking to the bag. If I am re-veneering a piece of furniture, as I said above I use hide glue because it is very forgiving and can be reversed if an error is made. Titebond is a really good adhesive, but even the III is relatively quick grab and not non-reversible. I wouldn't recommend it for veneering, though I use it a lot for other tasks on new furniture (never on antiques).

[ian]

I'm sure I've seen it "recommended" in one of the US mags -- Fine Woodworking or Popular Woodworking or Woodwork Magazine
here is a link Iron On Veneer / PVA Glue Method

[auscab]

I used to watch an older guy do a similar method on small patches, re gluing new or loose cross banding in restoration when he was in a hurry sometimes. He had it working well and every time I tried It didn't work so well ! I never kept trying with it and didn't like it . He and I were not letting it dry first though. Wet glue on, then veneer then iron it dry was the way . I stuck with hide glue, hammer veneering it with a veneer hammer. Or Gluing veneers with PVA or two pack (Araldite thinned) under cauls in a press. And a some large vacuum work . My favorite is with cauls and clamps or a press . If you have enough clamps with the correct spacing it works very well .

Recently I visited a friend who had a job converting a Walnut veneered upright piano into a drinks cabinet. He took off all the old loose Walnut and re veneered the whole thing using the Titebond method of coating, letting it dry ,then ironing on like being talked about here. He completed the job but it took him a lot longer than he thought and it was a what I would definitely call a nightmare of a job. So did he.
I was running my fingers over it testing for bubbles or spots that had not taken . They stand out clearly by the sound they give off when you brush over them lightly with fingers . If you miss one they don't show up until the final stages of polishing when your getting a good reflection. So you quickly learn how to detect them after that happens . His glue work had worked perfect though and there were no bubbles to be found on what I checked .

If you have a low spot that needs fixing though and you fill it with some kind of filler , there is a possibility of heat affecting that and it lifting off . That's one good way of letting epoxy and PVA type glues to let go when its simple butt joins between two pieces. You would have to get it pretty hot . Google the temperatures they let go at . I would probably solve that problem by Planing the whole top down flat and if it needed to have the thickness back Id press on a 3mm solid piece or what ever the thickness in the same grain direction. Provided a cross banding or edge veneer was hiding the add on .

Rob

[David N]

Ive had second thoughts about ironing on the veneer. Perhaps the best way is to use Titebond 3, using a veneer vacuum press to adhere the veneer to the top. Any comments? A mate of mine has a vacuum press which we can use but I intend to make my own. What vacuum pump would be required and would ebay be the best place of purchase?

[Robson Valley]

Modern luthiers of fine stringed instruments are still using 4 different kinds of hide glues due to the reversible thermal character.
Stewart-MacDonald (aka Stew-Mac) is a very high profile luthier's supply.

[auscab]

Any comments?

No , But a question .
How big is the top ?
And do you have a picture what sort of table it is.

Rob

[David N]

The top is 940mm x 450mm. The table is an old walnut bridge table with a folding top, inside has a round layer of felt glued to the inside of both tops, which when folded out, forms one shaped playing surface. The edges have been french polished, that is why I will use Titebond 3, so the glue hopefully will be easy to clean up with water and wont damage the edges, even though I have taped all edges with tape.