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Jeremy Woodoff
11-03-2006, 01:53 AM
The case of this clock, which is the subject of an earlier post regarding its movement, has a lot of lifting mahogany veneer. The veneer is fairly thick. The lifting is both at edges and in the form of bubbles. You can see one of the bubbles in this picture at the top right side, but I think someone previously glued the edge. There are other bubbles in the middle of the side panels.

http://mb.nawcc.org/images/imported/2006/11/1.jpg

A search on the MB found three options for repairing the lifting veneer (other than dismantling the case and soaking off the veneer, which I don't want to do). One is to use heat to soften the glue and press the veneer back down. I guess a warm clothes iron is used to do this. The second is to inject 140 degree water behind the loose areas to re-dissolve the glue, and the third method is to inject fresh hide glue behind the loose areas. Can anyone recommend one of these methods over the others, or explain the pros and cons of each?

If I use fresh hide glue, is the Titebond liquid kind OK for this application? Should the glue be thinned with water so it also helps dissolve the old glue? Will an iron warm enough to melt the glue affect the shellac finish?

I will appreciate your thoughts and suggestions.

Jeremy

Jeremy Woodoff
11-03-2006, 01:53 AM
The case of this clock, which is the subject of an earlier post regarding its movement, has a lot of lifting mahogany veneer. The veneer is fairly thick. The lifting is both at edges and in the form of bubbles. You can see one of the bubbles in this picture at the top right side, but I think someone previously glued the edge. There are other bubbles in the middle of the side panels.

http://mb.nawcc.org/images/imported/2006/11/1.jpg

A search on the MB found three options for repairing the lifting veneer (other than dismantling the case and soaking off the veneer, which I don't want to do). One is to use heat to soften the glue and press the veneer back down. I guess a warm clothes iron is used to do this. The second is to inject 140 degree water behind the loose areas to re-dissolve the glue, and the third method is to inject fresh hide glue behind the loose areas. Can anyone recommend one of these methods over the others, or explain the pros and cons of each?

If I use fresh hide glue, is the Titebond liquid kind OK for this application? Should the glue be thinned with water so it also helps dissolve the old glue? Will an iron warm enough to melt the glue affect the shellac finish?

I will appreciate your thoughts and suggestions.

Jeremy

shutterbug
11-03-2006, 02:15 AM
As for your last question, yes, shellac is sensitive to heat. I doubt you are going to get the results you want with any of the proposed methods. Your best option is removing the veneer and replacing it. Whatever is causing the bubbling in that area is eventually going to show up in other areas too. I can foresee a long frustrating project if you try to patch it.

Scottie-TX
11-03-2006, 08:04 AM
If you've never done it before, the first time's a tad of a challenge but you'll see the process work as you proceed.
Now the lifting at the edges is the easiest place to begin because it's easiest to access. My procedure is to gently insert a thin blade like the long X-Acto one? I gently insert it searching for further weaknesses. See, ya wanna get not only what's lifted but ALSO any other area ready to lift. Sometimes I leave a blade or spreader in the gap to allow glue to enter better. It MUST be clamped - entirely and evenly. Best to start clamping innermost and working your way out. You want to force the excess OUT of the area and not trap it IN the area.
Now that lifting, top front may be a challenge. Often you may need to dismantle the case so you can gain access to the edge. Once you have access, then the procedure is the same as any repair from the edge.
And, yes - hide glue'll work just fine. I see no need to remove this veneer. It IS tedious but it WILL work. Make sure you using clamping blocks. Have at least a half dozen clamps ready, and often I place waxed paper between block and finish so you don't glue the blocks to the case! G'luck matey!

og_boy
11-03-2006, 11:53 AM
if possible I use a horse syringe with the glue and shot into the lifted area (dry veneer)then use wax paper and blocks with clamps and as much clamping pressure as possible

Sooth
11-03-2006, 01:15 PM
I would suggest that you repair only the lifting veneer (edges), using HIDE GLUE ONLY. Other glues will not stick to the old hide glue residue, but new hide glue will bond to old hide glue.

If the bubbles REALLY bother you, this would be a much more delicate repair, and if not done properly, it couls seriously turn into a total botched disaster. If the ereas are only as small as seen in the photos, I'd say they are passable. Remember: the clock is very old, and imperfections from age, and handling will not decrease the value. However, bad repairs and modifications will.

The only way to repair a bubble in the centre of a piece is to very carefully cut a thin, small opening, and introduce some glue (hide glue) with a small seringe (needle). That done, the bubble is then squeezed flat to remove excess glue, and then the area is clamped down flat (preferably left overnight to dry completely).

The part that is very difficult is to introduce the glue under the bubble. If you're lucky, the veneer has already split open in the affected area, if not, the "opening" must be extremely well done to avoid being noticeable. It may need to be filled and the finish repaired in the area(s) where the repairs are done.

This is why I'd suggest doing the minimum of repairs, since you don't want to lose the original finish.

The clock looks perfectly fine to me, actually.

Hope this info was helpful.

Jeremy Woodoff
11-03-2006, 01:40 PM
I really appreciate the advice from everyone. Sooth, the case is worse than it looks in the photos. I was surprised when I got it how much of the veneer is loose--probably 2/3 of the front and 2/3 of the curved top. The top is tight at the front and back edges, and there is a split running most of the length in the center, where the veneer is detached. One side of the case has a couple of 2-inch bubbles, but they are already split.

I actually have done veneer repair (both replacement and re-attachment) so I'm not a complete novice, but I've never had such an extensive amount to do. Also, I've always been able to clean the old glue off the veneer and/or underlying wood. I'm concerned that injecting new hide glue will not completely melt the old glue, and there will be lumps.

Also, what do you typically use for blocks with the clamps? Most lumber is slightly warped, and I think for this kind of work the block must be absolutely true and smooth, or its imperfections will be visible in the finished product.

The finish on this case is very nice, only needing a little cleaning, so I definitely intend to take a conservative approach so as not to destroy it.

Further thoughts are welcome!

Jeremy

Sooth
11-03-2006, 02:02 PM
Well, I suppose your picture is very deceiving then. It doesn't look like it's peeling at all, but I will take your word for it, since obviously you want advice on repairing it.

For clamping blocks, I usually use scraps of pine, which is a nice soft wood, that won't mark the finish. The key is finding good wood. Good lumber is NOT cupped. Anything you buy at a lumber or hardware store is complete CRAP. All this wood will automatically be "air dried" wood, which is fine for exterior use, but not for furniture. Good, flat wood MUST be kiln dried, and you can get good stuff from a proper lumber/hardwood dealer. In places like this, they often have scrap bins, and if you just need a few decent flat blocks they can probably give you off-cuts for free.

I would also recommend (as above) to use wax paper in between, so that the glue doesn't squeez out and get permanently attached to the case.

As for the glue, you don't need to "disolve the old glue" with the new hide glue. you just need to renew the bond with fresh glue. If your glue is thin enough, you shouldn't get any bumps, unless you've A: disturbed/scraped inside the lifted area, or B: got some dirt/dried glue bits, or other "Crud" inside the crevice.

You won't be adding enough glue that the hole will be "stuffed" with it like a turkey. Just enough to re-moisten the area. The old glue will stay in place, and go back to the same spot it was before, and any new glue will simply fill any leftover gaps.

I would strongly recommend NOT using any other type of glue. I don't know if that's where you were heading with the "I can scrape off the olf glue fine" comment, but I will just make that statement again just to be sure.

Hide glue can always be undone if the repair turns out to be unsatisfactory. This will be much harder (or near impossible) with modern glue.

RJSoftware
11-04-2006, 12:58 AM
Do you have a steamer? I got one from the Goodwill. (startin to love that place).

Anyway, you can remove the veneer slowly by steaming the surface and working inside of those loose edges.

But it takes some time.

I think this is different than soaking the wood in bathtub overnight. I don't think you have to worry about the structural wood getting soaked and warping or anything like that.

I would remove the backboard of the case if it had any labels. That and the window frame and all. To avoid possible steam overspray damage.

It's better to remove the whole sections of veneer that are giving you problems instead of spot repair.

The veneer will come off in 1 piece and will be perfectly shaped so after you lay on a new coat of hide glue (thick and hot on both sides), you'll be able to lay it right back on nice.

I use ice cubes in a couple of wraps of plastic bag to tack weld stubborn spots. After you squeeze out the excess along with the bubbles, take the plastic covered ice cube and hold against the stubborn spots for about 30 seconds each. It gels (holds) veneer in place.

If you want to do the patch type veneer glueing.

You can buy a hypodermic needle type turkey baster. I got mine at Walmart.

But I had to beat the needle part flat. It cracked a little at the edges but it works fine.

For clean up I run hot water from sink on needle and then draw in/out hot water to clean it.

It works sorta so-so. I make the hide glue watery enough so the hypo can suck it up and spit it out. But thin watered down hide glue does not tack (ice cube trick) as well.

For the bubbles you can take a razor blade cut with the grain across the bubble and push one side down and slip needle in. Then vice versa to other side.

Massage it in and use gravity in all directions to help hide glue get deep in cracks.

It works, but leaves something to be desired because as soon as your done with one, another seems to pop out of nowhere.

RJ

Jeremy Woodoff
11-04-2006, 03:52 AM
I always use hide glue for this kind of repair--the "Titebond" liquid kind. The scraping I was referring to is for veneer that has completely come off the case. On this clock, I will take Sooth's advice and not stick a knife in to try to scrape anything out. It sounds like that can just dislodge the old glue and make more of a mess. If I see there is already crud between the veneer and carcase, I guess I will try to get it out with gravity or air.

To "clamp" the curved top I'm thinking of sandbags.

Anyway, it will be a while before I get to this, but I'll keep the Board posted on the progress. Thanks again.

Jeremy