Question regarding gluing veneer

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I need to glue two layer solid cherry veneer, no backing, to a sheet of 72" H X 38" W sanded plywood. I have never used veneer before, need guidance.

I'm going to use Titebond 3, recommend by both Titebond and the veneer manufacturer. Reasons: wood on wood, plenty of time to straighten the wood grain, and should I create voids, I can reactivate the glue with hot clothing iron.

I've got two methods in mind, as I do not have a vacuum bag, and no large flat surface, so;
1. Glue in two sessions, half at a time on my 19" wide work bench, permitting weighting down with half of plywood supported off the bench.
2. Glue in one shot, on game room floor that has 6" X 6" tiles and grout lines, or maybe on top of area rug on tile, rug being about 1/2" thick and fairly firm, again with weights available - big artificial Xmas tree box, luggage, etc.

Am I way off base here?, anybody have better solution?

Thanks.

21 Replies

I would do "2" Oldtool. After spreading the glue and placing the veneer on use a rubber roller to make sure all surface is free of any trapped air bubbles. Then weigh down. 
I’ve been practicing for veneering a five-foot circle. Hammer veneering will probably be the approach I take (because hot hide glue will set when it gets cold), with the workpiece set on sawhorses in the driveway, but I’m interested to hear how your attempt goes.

May you have the day you deserve!

I think that you really need a good way to get even clamping pressure over the entire surface.  Perhaps you could make some clamping cauls and lay a piece of plywood over the surface to get uniform pressure.  

Sorry but I think that it may be impossible to get even half of a 72x38" sheet and the substrate covered with TB3 or any PVA glues before it gets tacky.  PVA starts to dry very quickly and that is a lot of area that you have to get evenly covered, get it in place, J-rolled and clamped flat.  Sounds like a potential disaster to me.  If you were talking about an area no larger than about 24x24, it might work but any larger and I think it is bound to fail.   I've never tried them but Urea formaldehye glues may be a better choice than TB3 but also requires uniform clamping over the entire surface. 

I am a little skeptical about the idea of reactivating the TB3 with an iron, if there is a spot that doesn't adhere.  From my understanding, you will only get one shot at that.  I've only every used heat to debond PVA glue and once it was heated, the glue was ruined and certainly would not readhere.  I've seen a demonstration were you spread PVA glue on the veneer and substrate.  Once the glue has dried, you lay it in place and iron it down.  I have not tried it but the guy who demonstrated the technique said that if it doesn't adhere the first time, you cannot try heating it again.  You get one shot at it.  I would definitely experiment with the TB3 first with some cheap veneer on a practice piece.  

I too have done hammer veneering with hot hide glue but doing that on a 72" long piece without experience might be a little challenging for a first attempt.    With limited experience, I probably would also do it in strips narrower than the 38" as you have to get it "hammered down" before the HHG cools and gels. Hammering is soft like using a hard squeegee to press out the the excess glue underneath the veneer and requires no clamps, cauls or weight on top.  Probably not the technique you want to try for the first time on such a large project but it is a great way to apply veneer.  

--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.

Thanks for the advice from your life's lessons gentlemen, very much appreciated. Now I think this old dog is barking up the wrong tree here, and I'm wondering how this bookcase would look with a dyed plywood back. It'd be a shame not to use this beautiful veneer, but even a bigger shame to screw up the whole thing with a shabby back.
Thank you all for your input, your experience & knowledge will give much to think about while I finish the trim & ornamentation on this.
Yeah. As Nathan said, hammering with HHG is challenging on bigger pieces. My sweetie has asked multiple times about the tabletop I’ve promised her, and my current experiments are up to about 6 inches square, rather than the 5 foot diameter I’ll need for the tabletop (though any individual piece of veneer will be no more than 8 inches by 24 inches). But that technique should work for me with more practice, and I’ve got a sample pack of veneer from veneer supplies which I’ve been working with, and I’m trying larger pieces each time around. I’ll get there eventually, but the tabletop is getting some ash burl I got from CertainlyWood that is definitely beautiful, but also somewhat tricky to work with, as it’s burl.

Anyway, I definitely don’t know the answers, and while she would like to have the new tabletop sooner, we don’t have anyone visiting until next spring, so I’ve got at least that long to figure out my technique and clear enough space to set up the sawhorses and such in the shop. Plus it’ll be too cold outside for hot-hide-glue soon, so I can work on smaller practice pieces over the winter. Simply getting space to work on a 60” piece of wood (it’s a 5 foot square of ¾” cabinet-grade plywood, so I don’t want mistakes there, either) is a challenge most days.

To give you an idea of what I’ve tried and rejected so far, I tried TB2, which has a pretty good open time. But I had problems with it oozing through porosities in the veneer and gluing the veneer to my clamping cauls, even after treating them with wax and/or packing tape.



I tried with TB hide glue (which has a longish open time, especially if you thin it) and had problems with the veneer creeping as I clamped it. At least that I could remove by soaking the veneer with water and hitting it with a heat gun to soften things up, and I could reuse the piece of veneer.



The little practice box has taught me a TON so I strongly recommend working on smaller pieces first to figure out what works for you. I’m planning a 2’ circular table, or maybe a round box next, which I’ll veneer with four pieces of veneer, each a quarter-circle, which will get me experience butting the seams together that I’m going to need for the center of my table-top.

I encourage you to stick with the idea of veneer, Tom, because then you can learn stuff that might help me, too. ;-)

May you have the day you deserve!

If it's just a back for a bookcase, why not use contact cement?

Figuring out how to do something you have never done is what makes a good challenge.

Contact cement may be the easiest approach for this purpose.  I have not used it for veneer but I have used it to attach other thin materials to a plywood substrate and it is pretty easy to do though you also only get one shot at it.  Once it makes contact anywhere you pretty much have to go forward.  

One of the nice things about hammer veneering with hot hide glue is that it is completely reversible if you screw it up.  Heat and moisture will soften the glue and you can re-hammer it down and you can do it as many times as necessary.  You can even completely remove it and start over.  I simply wet the spot and place a wet rag over it and used an old cloths iron to reactivate the glue so that I could re-hammer.   I think the key to being successful on this panel would be to cut the veneer into narrower strips -- 4-6".  You just need to make sure that the edges are nice and straight.  If the veneer is thin enough you can use a utility knife and straight edge to get nice straight lines.  Just becareful that you don't let the knife follow the grain as you cut.    The length is also a concern but as long as the temperature is not too cool (you can warm the substrate with a heater before you apply if necessary), with narrower strips , I think that it would be doable based upon my experience.   

Of course you have to get a way to heat your glue and get or make a veneer hammer but you can use a crock pot and there are several examples around for making your own hammer.  I learned most of what I know about the technique from Shipwright's blogs on Lumberjocks, though they screwed up the blogs so badly during their conversion  that they may be follow now.  Not sure if he has also posted them here. 

This was my first hammer veneering project.  The veneer I bought was in 5 or 6" strips and as you can see were cut into relatively short pieces. The most challenging part was the interior ring.   I cannot imagine trying this with any other technique, especially as a first attempt.    Contact cement would have been really difficult on this project as would have other veneering techniques.  Hide glue actually made this pretty easy. 

--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.

Contact cement is often suggested for veneer. I’ve had about zero successful attempts using it, since I’m a klutz, and can never set the veneer down in the right place on the first try. Your mileage, as they say, may vary. Professional driver on a closed course. Do not attempt on public roads.

May you have the day you deserve!

Well gentlemen, all wise responses that give me plenty to think about. I am definitely sticking with the veneer Dave, I bought a 4' X 8' piece made to my specs and l have no other use for it. As to my current thoughts, here goes;

Regarding contact cement; first - I'm afraid of the fact that once it touches down, "you pretty much have to go forward." as Lazyman says, and I know from my experiences I'll never touch down where intended. Second - the smell is a killer. I helped a neighbor once years ago, who needed me to attach via a lap joint two sections of quarter inch ply for his new bay window sill, using his wood & his glue. I understand now why he wanted it done in my garage, my wife complained about the odor for a week.

Dave and Lazyman, you both mentioned using thin strips on a large surface, and I think you guys are on to something. The veneer I have was peeled from one cherry log that resulted in a repeating pattern of what looks like vertical boards side jointed, and as Lazyman suggests, I can cut it in strips with a razor knife. It's only about an eighth inch thick, and cut straight or not, the strips will match when assembled in the same order. I'll try to pick a section that looks like a board joint, and I'll need some working time for realignmen, so I guess it's just a matter of glue selection.

Thank you Dave, Lazyman, and Bentlyj, I'll post the bookcase project with the veneer details included. Right now, I'm finishing the molding trim,  have time to think about glue.
They do make low odor water base contact cement. Weldwood has always been a leading brand in my opinion.
I never use the water base, but it should be perfect for your application.
If you wanted to use it, I could give you some tips with pictures so you could stick it perfect first time. Let me know if you change your mind. 
It's definitely easier than cutting strips and trying to put them back together.

Figuring out how to do something you have never done is what makes a good challenge.

Thank you Bentleyj, I looked into the low oder water based Weldwood, but my concern with that is that fact that manufacturer instructions say to turn off all flames even though it is labeled Non-flammable. That makes me wonder how Low is Low.

FYI re: Weldwood low odor and non- flammable glue;
and I'll need some working time for realignmen, so I guess it's just a matter of glue selection.

I liked working with the TB Hide Glue, but its open time was longer than I needed. Hot hide glue has been best for me, because of its relatively short (but controllable by dilution and heat) open time, so I don’t need to clamp anything, but can just keep pressing the joint together by hand until e glue has cooled enough to set.

Might be you’ll work differently and find a different answer, but if you are going to try hot hide glue, I would recommend the BT&C hide glue granules in either the 192 or 251 gram strength. The Piggly No Wiggly glue from The Schwartz has a gram-strength of 250, and is another good choice. I prefer the granules, as I don’t have any worries about them aging until I mix up a batch, but pre-mixed is definitely easier if you know you’re going to use it relatively quickly.

May you have the day you deserve!

The thing that makes hot hide glue so great for veneer is that as it cools down, it gels.  The hammering process basically forces the excess glue and trapped air out through the edges of the veneer.  You press the glue out towards the edges with sort of a squeegee action.  As the glue gel, it starts to lock the veneer in place and the vacuum created by the hammering action causes the atmospheric pressure to act as your clamping mechanism.  The gelled glue prevents air from being sucked in and the veneer is locked in place.  The gelled glue even seals cracks in the veneer the same way to prevent air from getting in that way as well.    Of course this is also what makes it difficult to use it for larger pieces of veneer, at least for hammering.  You have to get all of the glue pressed out before it cools enough to gel.    For larger panels, they often us a heated press to lengthen the time.  You can see a heated press being used for some smaller marquetry panels in the video below.




The video that convinced me to try hammer veneering for the mirror I posted above was this video by Shipwright (with plenty of advice from him as well).  It really is as easy as he makes it look.  That doesn't mean that it doesn't take some practice but for smallish projects, it doesn't take a huge learning curve.







--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.

Wow, trying veneer with that large of surface as a first is bold (and risky).
I know that depending on the woods and dimensions, when you go big you really need to use the proper glue or changes in expansion can cause the veneer to crack and do other undesirable things.
Contact cement, as a process, can be laid easily enough when treated like laminating a counter top (use slats to elevate the laminate, position, then remove slats from the middle outwards).
Without hammering, a vacuum bag, or other flat, high pressure clamping method you are destined for a lumpy surface.

Paul (Shipwright) certainly is the go to help desk guy here.

Dave,
TBII has that bright yellow color that makes for hiding squeeze through nearly impossible. The viscosity is also way too much IMO.
I have had success for controlling squeeze through by eventually learning how much glue is enough. Before then with waxed cauls, I'd lay two layers of paper towel between the caul and veneer before pressing. The paper absorbs the squeeze versus having it ooze across the veneer surface. Sure, the paper will adhere to the pores where the glue comes through, but a quick scraping easily removes that and no dealing with the embedded mess of a fingerprint size glue stain to deal with.
 I know that depending on the woods and dimensions, when you go big you really need to use the proper glue or changes in expansion can cause the veneer to crack and do other undesirable things. 

From my research I found that its rigidity is actually one of the properties of hide glue that make it great for veneer.  When it dries, it is rock hard and experiences no creep.  From my research, I read that its rigidity is also what makes urea formaldehyde another good option for veneer.  PVA glue is very flexible in comparison, and contact cement is even more so, and the flexibility can eventually lead to issues, especially with wood veneer on horizontal surfaces like table tops.   That is probably not as big of an issue in the vertical context for this project.  

--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.

Dave, I had never seen Chris Schwartz's Piggly No Wiggly (gelatin) glue before.  Interesting.  Does it act like liquid hide glue or does it have a gel point like HHG does?  

In the video on the link you posted, he said that he came up this idea after wondering if Gummi Bears could be used as a glue.  The answer was yes.  I may have to see what that is like.  😀

I also like the idea of making my own but of course they didn't share the ratio of salt to gelatin that they use.  I suppose you could make it just like mixing up a batch of HHG and not have a shelf stable liquid version.  

--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.

TBII has that bright yellow color that makes for hiding squeeze through nearly impossible. The viscosity is also way too much IMO.

Yep. But TBII can be thinned with water, which is how I generally have used it for veneering. The downside is that thinning it lengthens the open time.

Does it act like liquid hide glue or does it have a gel point like HHG does?  

More like liquid hide glue, so it doesn’t have the quick gel that makes HHG work so well. That said, it’s not a bad glue to have on hand. I’ll be replacing my fish glue with Piggly No Wiggly once I’ve used it up or had it go bad.

May you have the day you deserve!

Wow, you guys are most generous with the information, so much so that I started to think this is a no-go for me, paint the back plywood panel. But then, I figure that why not try it, if I screw it up all it's going to cost me is the price of another 1/4" plywood from big box, and some paint.
I'm still thinking about type of glue to use, will study all your comments above as well as the videos provided, and any YT videos I come across. One thing for sure, per suggestions prior mentioned, I'm going to cut the big sheet into 3 strips for ease of handling. Studying the veneer, I've found 3 places where it looks exactly like a multi-board glueup. I'll do one at a time letting the glue dry for 24 hours, three days in a row.
Thanks for all the comments.