hammer veneering question

Anybody with experience with hot hide glue ? Have used this technique numerous times, using classical method (Coating both sides, got excellent adhesion with curly walnut). Sanded to 320, but there were obvious areas of bleed through (which is not supposed to matter), but when shellaced, there are multiple blotches. Any advice , other than ripping it out ? Has anyone tried sealing the underside surf. of veneer with shellac before gluing ? Thank you. Alan

I've done a fairly large project with hot hide glue and a veneer hammer. My experience was that it is a steep learning curve but quite versatile. I tried hot glue on both sides but then the iron I was using started stinking from roasting hot hide glue. I quickly switched to light misting with water to counter the curling. It worked out ok. I'm wondering about the bleed through, was there glue still left on the surface versus bleed through? If this is the case, you might be able to sand it out still. If you are sanded down to the thinnest possible and it is bleedthrough from the back, I don't know a great fix.

For the sealing question, I'm skeptical on the utility of that. First, the pores in walnut don't get sealed well with shellac so bleed through will still happen and second, it might make the hide glue adhesion much less strong by interfering with the integration with the wood fibers.

Thanks for that , Mike. I just read about the sealing thing somewhere; never tried it. Also, never had this problem before. Maybe it's the veneer porosity or thinness.

Walnut veneers are fairly porous. I vacuum pressed some walnut burl a few months ago and quite a bit of glue seeped through. Definitely not as porous as oak but still much more than maple for example.

I'm not sure if this will help at all but... I ended up just putting a linseed oil on the drawer fronts and seemed like the oil didn't really soak in but the cherry wasn't blotchy.

http://www.sawmillcreek.org/showthre...lue-for-sizing

I haven't yet done any hammer veneering just pressing with clamps.

Thanks for that, Judson. I read the links. Sounds like you're saying to wet the face surface with the 10% sizing mixture. Does that need to be kept hot (like the full strength ) ? And, I presume, it doesn't weaken the bond for the water to penetrate to the glue layer ? Or, ...maybe I'm misunderstanding : Does the size solution go on first on the glue side of the veneer and allow to dry, like other sizing procedures...yellow glue, for example. If that were the case, it would cause a lot of curl, and need wetting on the outside surface. Funny, I've been doing this for years, and never had a problem until now. Hoping that if I put the final finishes on, etc, maybe I won't notice it (ha !), or maybe just put the table in a dark part of the room. Alan

I used liquid hide glue (the stuff in a bottle) to glue the veneer to the substrate by pressing with clamps. Had bleed though so then squeegeed liquid hide glue full strength on the surface trying to emulate what you might do by hammer veneering. Then ended up scraping/planning most of that off and made a mixture of ~10% (just eyeballed it) liquid hide glue and water. I'm not using traditional hide glue at all, I've no experience with it other than what I've read and watched on TV and YouTube. I did not size before applying the veneer to the substrate.

Hope it helps but I feel you have way more experience at this than I and hope I'm not mucking up your thought process.

Good luck!

Sounds like putting a coat of hide glue on the entire piece when your done would be the way to go. I think I may have seen this on the Woodwright show. I have no experience but I'm pretty sure I would do that if I had bleed though. At least nothing would look out of place.

Thanks again for all replies.

Bleed through should not be an issue when hammering veneer. Traditionally both sides of the veneer are coated with glue, the glue on the top acts as a lubricant for the hammer and it helps seal the grain. If your iron is sticking and you are burning the glue your iron is too hot. There are lots of videos on YouTube.

I do use an iron when using yellow glue iron on technique, but only use it to loosen a piece of veneer when using the veneer hammer.

Alan, I must be missing something, if you are coating both sides of the veneer with hot hide glue, how can the blotching be caused by bleed thru?