# repairing 40 yr old marquetry coffee table



## worldgeezer (Nov 26, 2018)

(hoping this is the right forum).
newbie here, though with some experience in woodworking. But that's a topic for another day.

I'm repairing one of Grandpa's coffee tables which he created winter 1973-75.
These tables all have a variety of wood "veneers" in general about 1/8 thick.
The pattern for this table is labeled "church window" though that may be his label.
Some of the Amaranth and some birdseye maple veneer / inlaid wood pieces have warped, pulling away from the 5/8 plywood substrate. He apparently used double stick tape to affix the veneer. See attached photo. 
I've succeeded in removing the veneer pieces that make the center design. The edges of the pattern (about 2" wide) seem to still be firmly attached. I might be able to remove them … haven't tried yet.

My questions:
1. The birdseye maple veneer (slightly warped) seems somewhat flexible enough; that is I can gently press it flat on the workbench. So, do I need to put it in a press for a while to flatten it before re-attaching it? What about the pieces of Amaranth that have the same problem of warping?

2. What are your recommendations for glue? I'll stay away from contact cement; would also like to stay away from white glue because it's rather wet. Is Titebond recommended? Hide glue? (never used it before); Rockler's veneer glue; something else?

3. The plywood substrate appears flat. But, when regluing all the veneer pieces to the top, should I also put a thin layer of glue on the underside of the substrate, to seal it, thus to try to equalise any tension that might result when the top is repaired?

4. Note that I don't have a vacuum bag press, so will have to find a way to clamp the pieces. Should I glue and clamp each piece? Or, tape it all together and then glue it all back down (approximately 2 ft x 4 ft).

4. When all the veneer pieces are back in place, should I use a scraper or else use very fine sandpaper to remove the old finish. I do not know what it is. It does not appear to be discolored, but is uneven.

5. What are your recommendations for a finish? Shellac? Varnish? Wax? Other? How long should I wait (after gluing down the veneer pieces again) before applying a finish?

Well, that's about all the questions I can think of.
I appreciate the experience you all have.
eb


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## shipwright (Sep 27, 2010)

Your picture will help a lot but:
-The pieces can be flattened easily by spraying with a little water and pressing (preferably between hot cauls but not necessary.)
- Liquid hide glue (Old Brown Glue preferred)
- If the pieces are flat you only need glue on the substrate but it certainly doesn't hurt to coat both surfaces. (Nothing to do with relieving tension.)
- If you can assemble the piece on tape first and apply as one piece, that is definitely the way to go.
- 1/8" is pretty thick for marquetry so a good sanding won't hurt it. It will also bring back the original colours.
- I like shellac, French polish to be exact, but a padded or even brushed shellac finish will look great and more importantly be reversible.

Feel free to PM me if you like.


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## RichT (Oct 14, 2016)

Of course you can PM about this, but if you're amenable to keeping it in the thread, I'd like to follow along and learn something.


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## worldgeezer (Nov 26, 2018)

hello shipwright


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## worldgeezer (Nov 26, 2018)

well, for some reason, photos don't post …


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## worldgeezer (Nov 26, 2018)

still working at cleaning up the various pieces of veneer, almost done with that.


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## worldgeezer (Nov 26, 2018)

however, given that I might get to taping the various pieces together (prior to re-laying on the substrate), and that these pieces are about 1/8 thick …

should I put glue on the edges when assembling them together? Except for the center "medallion" (about 6" x 6"), the pieces are reasonably large.

Thanks,


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## shipwright (Sep 27, 2010)

A picture would really help. You should be able to attach one by clicking on "img" above the comment box and following the prompts as long as the picture is stored on the device you are using.
Failing that PM me and I'll give you my email address. To PM me click my avatar to go to my profile page and then click "send message" under my avatar there.

Welcome to LJ's. It gets easier.


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## worldgeezer (Nov 26, 2018)

note to Shipwright … used Internet explorer to attach pictures; chrome browser wouldn't work

light colored warped veneer is birds eye maple; it's still flexible enough that I can flatten it by hand;
the center dark-red is Amaranth / Indies; it also has some warp but not as much as the maple;
dark lines are ebony, some of which is brittle.

I've gotten all veneer pieces off now, scraped & sanded off all the adhesive. Will likely need to rough sand ( # 50 ) to enhance adhesion of glue.

the border (multi-veneer) is still affixed to the substrate. it doesn't seem to be coming loose … though I'm wondering whether it would be better to remove it … probably also attached using double stick tape. 
What are your thoughts?


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## shipwright (Sep 27, 2010)

The picture makes a lot of difference. Is the ebony just the border around the maple or is there a strip between the maple pieces? 
To keep thinks manageable I think I would try to get the ends done first probably one at a time. This would include the ebony strips and the maple pieces. 
I would recommend Old Brown Glue and whatever you have for pressure. First choice mechanical press, second vacuum, third clamps and slightly curved cauls. All will work. 
Once that is secure you can get the amaranth done and finally the smaller pieces. They could go in as a group with tape. 
Dry fit as much as you can to be sure things will fit and be prepared to make little adjustments if necessary.

When all that is back together you could give the other pieces a little pry to see if they come off. They will be easier to place with the centre all done.

Does that sound doable to you?


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## worldgeezer (Nov 26, 2018)

reply


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## worldgeezer (Nov 26, 2018)

replies to comments above:
The picture makes a lot of difference. Is the ebony just the border around the maple or is there a strip between the maple pieces? 
> ebony border outlines all major pieces. See attached above. I'll try to attach a top-down photo to this message. Ebony strips are about 1/8 wide.

To keep thinks manageable I think I would try to get the ends done first probably one at a time. This would include the ebony strips and the maple pieces. 
> ok

I would recommend Old Brown Glue and whatever you have for pressure. First choice mechanical press, second vacuum, third clamps and slightly curved cauls. All will work. 
> will have to be mechanical press using clamps and blocks. Would love to use a vac bag, but not sure that I have enough time to apply OBG, then place pieces in sections, then get it all in the bag. Or?

> With your earlier suggestion on cauls (hadn't heard about them before), ... seems that I would need enough cauls side by side to cover the entire top, because of the number of different sized pieces and the layout, eh?

> OBG … have done some reading on it. Seems that it needs to applied hot? That could make things interesting. 
> Would PPR glue be easier to handle?

Once that is secure you can get the amaranth done and finally the smaller pieces. They could go in as a group with tape. 
> great idea to group amaranth with medallion

Dry fit as much as you can to be sure things will fit and be prepared to make little adjustments if necessary.
> right. great suggestion

When all that is back together you could give the other pieces a little pry to see if they come off. They will be easier to place with the centre all done.
> Ah, OK. makes sense.

Does that sound doable to you?
> very helpful comments. Many thanks. This is evening enjoyment after regular work, so quite likely I would need to do it in steps.


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## RichT (Oct 14, 2016)

One tip I picked up to locate loose veneer is to just tap it sharply with the tip of your finger. You'll immediately be able to distinguish between the sound of a solid surface and one that's separated.


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## shipwright (Sep 27, 2010)

Vacuum bags are over rated IMHO except for very large pieces. I have one and have never used it since I built my mechanical press. I have several reasons but they aren't relevant here.
All you need is a piece of 3/4 MDF or plywood (the platen) the size of the area you will be pressing and two or three or more if you like pieces (like 2×4's) that are slightly curved on the bottom (the cauls) to clamp across the platen. The curve means that when you clamp the ends the centre still gets pressure. The amount of rocker should result in even pressure on the centre and edges. It doesn't take much.

OBG will give you lots of time. It doesn't need to be hot, just warm. It is hide glue so it is reversible. You want that.

Did I miss anything?


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## worldgeezer (Nov 26, 2018)

Thanks for all the help, Paul.

I think there might be two questions still:
a) since the veneer is about 1/8 thick, should I try to get some glue on the edges of veneer pieces that are contiguous. Perhaps some of this will happen anyway.

b) try this project as a whole (all at one time), *OR *in three parts 1. birdseye maple + ebony strips, 2) amaranth and medallion 3) birdseye maple + filler ebony strips.

and a new question: should I score (or lightly sand with # 50 paper) both the substrate and the underside of the veneer to enhance glue adhesion? Both seem rather smooth due to scraping off the old glue.

eric


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## worldgeezer (Nov 26, 2018)

> One tip I picked up to locate loose veneer is to just tap it sharply with the tip of your finger. You ll immediately be able to distinguish between the sound of a solid surface and one that s separated.
> 
> - Rich


Hi Rich, thanks for the tip.
I'll give it a test tomorrow. 
Seems likely that I might find some places where this is true since the original adhesive was double sided tape, and it wasn't all that difficult to remove the veneer in the central part of the design.


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## shipwright (Sep 27, 2010)

- I think it will happen incidentally anyway but there is no harm in wetting the edges as you assemble.
- if you can assemble it all ad dry fit it successfully then glue up and go for it. If you want to take it a little at a time, that will work too. All at once will require an organized and fairly quick moving process as well as a bigger platen and more cauls and clamps but if you can pull it off it is the best way. I think you have more opportunities for it to go sideways that way however.
- yes scratching it up is a good idea. You can do the substrate with opposing diagonal scraping with a hacksaw blade.
(If I thought you had a toothing plane I would suggest that.)
You can also wet the substrate (warm water) before applying the glue if you are using OBG. It will enhance your working time.


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## worldgeezer (Nov 26, 2018)

Hi Paul
Have another query for you:
All 8 large pieces (amaranth, birdseye maple), are currently "in press" to straighten the curl or warp. I dampened them, then wrapped in paper towel, pressed for an hour or so, then switched to new/ dry paper toweling, then put them back in the press. They are cool to the touch (it's about 55 degrees F in the garage). I rather doubt they are completely dry yet.
Since it's likely to be next weekend before I get back to this project I'm wondering if there is some way to stack these pieces so that they air dry completely?
Perhaps in layers with slats in-between, all under a weight of some kind?
Thanks


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## shipwright (Sep 27, 2010)

The best way to keep them flat is to keep them pressed. Just change te paper every day. You can dry the used paper and use it again. If you let it air dry even with weight, it may curl again. Best to keep it flat until it is pressed to the substrate.


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## Sylvain (Jul 23, 2011)

Paul, what do you recommend between the veneer and the platen to prevent them gluing together?


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## shipwright (Sep 27, 2010)

> Paul, what do you recommend between the veneer and the platen to prevent them gluing together?
> 
> - Sylvain


I always use a couple of layers of paper between the glue-up and the platens to prevent unintentional sticking. The paper can be removed with water after the (hide) glue dries. I use clean newsprint, available as packing paper in convenient size from stationery suppliers and movers.
It is also perfect for drying wet veneer when flattening.


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## worldgeezer (Nov 26, 2018)

finally getting back to this project.

Paul, you're correct I don't have a toothing plane - hadn't heard of it before. 
A little research led me to think that I could use a coarse saw blade to scrape the surface to achieve the same (or at least a similar result. Seemed to work well both for the substrate (40 yr old plywood) as well as for the underside of the large veneer pieces. 
See pictures.


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## worldgeezer (Nov 26, 2018)

Well, not quite (but I don't know how to orient the picture correctly). 
Definitely a digital migrant, I am.
Any of you admins have my blessing to turn the pictures correctly.


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## worldgeezer (Nov 26, 2018)

When I started to prep the underside of the center diamond (about 6" square), I realized that it had too many loose joints and the ebony trim (about 1/8) around the edges were mostly loose, so I blue- taped the upper side, cleaned off the old glue where possible between loose joints, then used OBG between the loose joints, covered it with wax paper then put it in my "press" (1" MDF)
see picture. 
We'll see tomorrow how this center piece turns out.

And if anyone really wants to know, my "workbench" is the freezer in the garage, covered by a discarded piece of counter top. No drawer space though.


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## worldgeezer (Nov 26, 2018)

27 December update
25 December pm: re-glued all the veneer, laid down wax paper, put it in my "press" 
27 December am: opened it all up, used damp warm rags & flat scraper to remove squeezeout OBG. Not too difficult to do, other than where there is difference in thickness between veneers. The ebony stripes are noticeably thinner than the birdseye maple, and some squeezeout had filled in there.
I layered it with paper towels to dry the veneer again … will change those out regularly over the next several days.


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## worldgeezer (Nov 26, 2018)




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## worldgeezer (Nov 26, 2018)

Background
have now re-glued (OBG) the central pieces of the design back on to the substrate.

I've removed all the "loose" (=easily removed) veneer ribbon around the edges. Most of it needed to come off. It was glued to something like card stock which was then glued to the substrate. Or, perhaps it was double sided tape that has disintegrated. One section seems to have been repaired earlier, based on the observation that it is (now) firmly glued down. (will try to post pictures tomorrow). I have all the ribbon pieces taped together into several larger "units" using blue tape.

I'll need to clean (and rough up) the plywood substrate.

Will need to do the same to the underside of the ribbon, though this could be a bit challenging since it's just taped together (very little glue between the pieces).
*Any suggestions on how to approach this*?

Then, after gluing all the pieces back down, I'm going to have a fairly uneven surface since no two types of veneer are the same thickness.
It's almost a philosophical question.
a) This being a "restoration" job, just re-glue the veneer pieces, don't change the original work any more than absolutely necessary.
b) after re-gluing the pieces that make up the ribbon, scrape it to where the various veneers are reasonably level. This could be a lot of work.

On a somewhat related question, and especially if option "b" is chosen, then would I use some sandpaper to smooth away any scraper-marks? 
Which grade of sandpaper?

*Your thoughts?*

thanks


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## shipwright (Sep 27, 2010)

Sorry, I've been away. I ended up in the hospital for a week over Christmas.
Looks like you have it well in hand and at doing a great job on the restoration.
To answer your questions:
-Use a finer blade like a hacksaw on the more fragile pieces. Actually it is all that is needed anywhere. Even coarse sandpaper would be fine.
-Your choice about leveling or not. Personally, I would. You can scrape or sand whichever you like. If you sand just be careful not to oversand the edges. Start coarse (60-100) to level and then go through grits down to ~240. Random orbit works better on marquetry than linear sanding as there are so many opposing grain directions.
You are doing a great job!


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## worldgeezer (Nov 26, 2018)

Hi Paul,

Many thanks for the suggestions. Glad you made it out of the hospital.

Now that I've completed cleaning the underside of the ribbon, (I have it all taped into about 8 pieces plus some pieces of longer veneers), I'm wondering the best way to get OBG in-between all the little pieces of the ribbon. 
Only idea that occurs to me (obviously a newbie here), is to leave it taped, but fold along the joint lines, apply glue along the joint lines, then straighten it again (some squeezeout is inevitable, but will be on the underside, hence not a big problem.
Then, apply glue to the substrate, press the taped sections in place, wipe down, then wax paper, clamps, etc.

The alternative seems to be to glue and hand-place each separate piece. Sure to be a sticky job.

Scraping that old glue from the veneer pieces … found at least four different glues, including white glue in a few places; other places - some kind of brown glue that had crystallized; in some places likely some kind of epoxy; 
In other places some other kind of brown glue that could be scraped off in a flexible layer (?possibly an OBG or equivalent? but it didn't respond to warm humidity like standard OBG does).
I finally figured out that it helped to use warm water and damp rags to try to soften some of the glue, though that didn't work everywhere.

There was (something like) card stock under all of the ribbon. Would have been interesting to ask him about it. Where the card stock was missing … veneer had come evidently loose and somebody used one of those other glues mentioned above.

I know he had a table saw; I don't know of any other electric cutting tools for use when making these ten coffee tables. I'm thinking that he must have had a backsaw and miter box or some sort of jig to cut the various angles.

I know he had catalogs from lumber and veneer sellers in Chicago, and made several trips there to pick out veneers. I wonder whether he might have purchased the ribbon already pre-cut (which might explain the "cardstock" underneath the ribbon). But even so, he would have had to cut at least some of the angled pieces by hand.

One or two of these tables have "checkerboard" patterns in the middle (mine does). But the squares were not uniform in dimension as I discovered when I tried to reposition many pieces that had come loose.

There are no written records of his work, and likely no photos either.

Thanks for your help. Paul.


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## shipwright (Sep 27, 2010)

Your method should work fine. I wouldn't try placing the individual pieces one at a time. That would just be messy. I think you're doing very well. Keep us posted.


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## worldgeezer (Nov 26, 2018)

three photos .. final glue up.
a) spreading glue into ribbon joints (taped together, blue tape)
b) detail of corner 4 (the last one)
c) all re-assembled, next: cleaning, then to press


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## worldgeezer (Nov 26, 2018)

Is there some way to orient the pictures "correctly"?
Not finding it in the help files here.
thanks


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## shipwright (Sep 27, 2010)

Looks good.

Edit each picture after you re-orient it. Just a tiny crop will do.


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## worldgeezer (Nov 26, 2018)

after some work related travel to Europe … an update
had to re-do some of the veneer pieces in the ribbon … too much space between them … not sure why this occurred though some of it seems due to micro size differences in original cutting.
I'd guess some is possibly due to shrinkage. But I don't really know.

Now, to shellac…. *are all shellacs the same*? or are some shellac better than others for a veneered coffee table?
What should I look for in a shellac at the box stores? Or would it be better to visit Rklr in the next town over from here? 
How does one apply shellac - rag or brush? 
I'm also guessing that "in a cold garage" might not be the best idea …what is an ideal temperature?


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## worldgeezer (Nov 26, 2018)

OK, I have a color puzzle

Grandpa described the four veneers in the center medallion as 
gray - popular
gold - mahogany
black - ebony
tan - birds eye maple

See attached photo.
birds eye maple, yes, 4 squares
ebony pieces, yes 8 of them (4 pairs of 2)
mahogany (not gold color) 4 pairs of 2 in center.
which means that the poplar picked up a green tint somewhere. I only discovered the green while sanding.
There are some 20 pieces of veneer which have this tint. Interestingly, though, there are other pieces (identified as "hollywood" - visible in the ribbon) which do not have this tint. The birds eye maple also did not pick up this tint.
I have no clues on the original finish, other than that it would have been something available 40+ years ago.
Any ideas?


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## shipwright (Sep 27, 2010)

Green is normal in freshly cut or sanded Poplar. It won't stay green but will be somewhat greener than other wood near it. I have several shades of green Poplar veneer.
For the best work I like to French Polish with fresh super blonde or platina shellac made up from flakes but for a brushed finish or a simple padded finish the Zinser products are fine. The secret IMHO to a great brushed finish is the brush. Look for Taklon brushes. I get mine from Homestead Finishing Products.


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## worldgeezer (Nov 26, 2018)

Very helpful … learning all sorts of interesting things here…  
I have a piece of poplar veneer left over from a different project … not a hint of green in it.

wondering whether I need to apply a sanding sealer to the veneer prior to using the shellac …. or is the shellac sufficient by itself?

How many coats?

And should 
a) I apply shellac to the veneer + substrate; and separately to the walnut frame*, then assemble it when dry, or 
b) reassemble the table into its walnut frame and then shellac it all? 
c) Or?

The walnut frame is about 2.5×3/4 wraps around the table, has a dado-ed groove that the veneer+substrate slides into and locks it into place. It has 45 degree corners … (I'll have a separate question about the frame, tomorrow).


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## shipwright (Sep 27, 2010)

Poplar comes in many shades.
Don't need a sealer. Shellac is a great sealer.
Until it looks like enough. Sorry but that's how I do it.
Assemble and shellac when all done and prepped.


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## worldgeezer (Nov 26, 2018)

OK, next steps …


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## worldgeezer (Nov 26, 2018)

OK, next steps … the top is sanded reasonably flat, still want to use a higher grit … tomorrow.
Should be warmer and more suitable temperatures for applying shellac.

Different question this time. The top is framed by 4 pieces of walnut. There is a dado into which the top will slide. It's not a tight fit in any dimension. I presume that's OK. The shellac may essentially serve to lock the pieces into a single unit.

Gramps (or someone) used metal brackets to attach the four walnut pieces into a frame. See picture.

While it held the frame together, yet the four corner joints were very loose.
I'd rather not do that.

Thus this question: what would be an appropriate way to solidly join the four pieces of walnut? I can think of 
1. using biscuits, since if I get it right, they would be concealed … though they wouldn't be really deep into the 45 degree face of each piece. This one isn't 100% sure, though since I only have hand-held tools to work with.
2. dowels. not an option that I can visualize
3. just glue … but this would be a rather weak joint.

Any ideas?

Thanks for all the help. This has been a fun project.


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## shipwright (Sep 27, 2010)

If the dados are glued, there should be little strain on the corners and glue alone should do but you could always put a spline in (matching or contrasting, your choice) as people often do in mitred boxes.


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## worldgeezer (Nov 26, 2018)

Well … what can a dime tell you

While while doing a light sanding after shellac coat #1, the thought occurred to me to check the (relative) flatness of the table, now that the veneers are reglued back in place and sanded level (some were thicker than others)

see pictures

There's a curve equal to the thickness of a dime. On the top side (veneered), the curve is in the middle, on the bottom side it's measurable on the two ends.
In other words, the table top has a drop-curve (a slight sag) in the middle,
US Dime = 1/16 inch

What to do?

My guess at this point is that there might not be much one can do.
..except perhaps find some way to clamp it flat for a day or two … or three or

And it's not hugely noticeable except when one lays a straightedge on it. But round objects would most likely roll to the center

I will note that the bottom side of the plywood substrate is not sealed, so I may well put a coat or two of shellac on it.

Your thoughts?

eric

first picture is at center, from top side of board (straightedge is touching the edge at both sides, on the top)

second picture is at edge, on bottom side of board (same thickness at both edges)


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## shipwright (Sep 27, 2010)

Best practice is always to veneer both sides to balance forces. This is the predictable result of not doing so. It is often not that necessary when the substrate is restrained as in part of a box etc and where the veneer is modern see-through thickness but with your substantial veneer thickness I'd bet that is the problem. I would try even at this time to apply a crossband veneer on the bottom of the plywood. Try for at least 1/16" if you can. 
Or you can live with the cup. The problem is it may not be finished cupping…...


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## worldgeezer (Nov 26, 2018)

Hi Paul,
Ok, we're well beyond my pay grade on this one.
A quick internet search on crossband veneer … appears to be (essentially) applying a cross-grain layer of veneer underneath the "show" veneer. If so, that makes a lot of sense to me.

I don't know whether this curve was already present when this coffee table was brought to me, or whether it's a recent issue.

What I'm working with … substrate is 1/2 inch plywood: 3 internal layers of just over 1/8 inch each, then a top and bottom exterior layer of just under 1/8 inch each, (probably sanded) to reach the 1/2 inch overall thickness. The grain-direction of the top and bottom pieces run parallel to the length of the substrate.

So, "cross band" in this instance means: apply several strips of this wood or veneer to the bottom (the underside) of the substrate.

Most of the veneer (all 8 of the larger pieces) on the surface runs parallel to the length

The "theory" seems to be:

because the curve is 90 degrees to the length, 
glue several strips of veneer running across the width. This seems to make sense because it runs 90 degrees from the direction of curve.

*Q:* Would the actual width of those strips be of significance?

*Q:* What type of wood is recommended? (If you can list several, it increases the possibility that I can find one locally).

Some of those strips may cover some of granddad's writing in which he describes the various kinds of veneer in this pattern. Small price to pay to try to stop or at least slow down the curving.

Then, when those cross-band strips are glued and dried, apply several coats of shellac as sealer across the entire bottom. At present, the bottom is completely unfinished.

Thanks again for the considerable help.


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## shipwright (Sep 27, 2010)

The fact that the veneer wasn't hard glued the first time probably saved it from cupping originally. You always try to place veneers at cross grain to the preceding one. This is what you want to do on the bottom. That's why I called it a crossband. Obviously you can't do that with marquetry but the one underneath should be done that way. Width doesn't matter and use whatever you can find in decent thickness.
By all means take pictures of the writing. There are ways to transfer printouts of it onto wood.


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## worldgeezer (Nov 26, 2018)

Late thoughts …

*1*. sanding the top to remove the fresh coat of shellac, let the top re-acclimate to current weather and humidity (quite humid over this past week), 
Then after about a week, shellac both sides.

*2*. Attach angle iron to the underside, rather than wood strips. Less likely to stretch (though I don't know how much wood actually stretches under tension).

eh?


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## shipwright (Sep 27, 2010)

Worth a try.


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## worldgeezer (Nov 26, 2018)

OK, have sanded the top.
It's currently "resting" under about 30 lb of weights laid out over the center of the substrate+top, lengthwise. 
We will have variable humidity and about a 30 degree change in temperatures over the next several days.
I've found some 40+ year old oak strips to use as crossbanding on the underside. It was about 30 years in an attic in hot summer climate, so ought to be dry enough. 
Do you think *4 strips* is adequate (about 3.4 inch wide each), placed about 8" apart.

-eric ..............the early bird may get the worm … great for the bird, tough for the worm


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## shipwright (Sep 27, 2010)

How thick? The idea is to be something like the same thickness as the veneer on top and should be a full cover layer but this is an unusual situation. What you suggest may well work. I have no experience in this particular set of circumstances. Sorry.


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## worldgeezer (Nov 26, 2018)

Paul,
Friday evening, went down to the big box store to look at thin woods, essentially plywood at 1/4 thickness.
It's quite flexible on both length and width dimensions.

Which leads me to recognize that it would help me (and possibly others) to understand the physics of what we're trying to do.

The substrate is 1/2 thick. Seems to me that if it's cupping with the veneer already glued to the top side, then how could a 1/4, several-ply layer effectively restrict or even stop the cupping?

The cupping seems to be relaxing, though just a wee bit thus far. The substrate has been (under weights as described above) since this past weekend. I don't have significant hope that it would completely flatten.

And your best intuition or guess will be far beyond mine. I recognize that in some way, we're trying to counteract (what I would call) natural forces of woods, humidity, etc.

Thanks.


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## shipwright (Sep 27, 2010)

Plywood is always made with an odd number of layers. It is essentially in balance. When you add another layer to one side, you mess with that balance. Adding a layer to the other side (at least theoretically) restores the balance.


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## worldgeezer (Nov 26, 2018)

Paul,

Over the past several days, did a lot of reading about veneer balancing on a number of websites including woodweb, found quite some interesting comments on similar topics. Starting to understand the difference between veneer (very thin) vs thin wood marquetry (which is what I'm dealing with).

Primary rule in veneering (and probably marquetry as well) is that "what is done to the top is also done to the bottom", thus obliged to match thickness and grain orientation. It's still something of an open question whether it's absolutely necessary to use the same species. This aspect gets into the physical properties of different species of wood - way beyond my pay grade.

Seems to me there are *two *options:
a) find some 1/8 in thin wood as wide as my widest piece on the top, cut out pieces the same size and shape as the eight larger pieces currently on the substrate top. Align & glue these to match the grain of the larger pieces on the top. 
Cut other pieces to match the overall shape of the ribbon and other smaller pieces. 
I'm *not sure* which way to align the grain of these since the outline of these shapes on the top includes smaller pieces with varying grain orienation . *Any suggestions*?
What about relative hardness of the wood … though I'd presume the pieces on the top aren't all of the same degree of hardness.

Or
b) cut a piece of 1/8 baltic birch plywood to fit the overall dimensions of the substrate, glue it as one piece to the underside. I'm not sure about this possibility since as you and others have pointed out, plywood is considered as "stable" which still leaves me with tension generated by the glued pieces on the top.

Thoughts?


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## shipwright (Sep 27, 2010)

You don't have to replicate all the grain directions on the top, that's for sure. 
One of the problems with getting information from the web (including from me BTW) is that you don't have to have any skill or experience to give advice. You often just don't know.
I would put a layer of 1/16" Poplar from Certainly Wood on the bottom in an orientation opposite to the one on te bottom now and see if it helps.
That's about all I've got.


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## worldgeezer (Nov 26, 2018)

thanks for the observations (tis a well-known subject) 
suggestion re poplar in opposing grain direction.
I'll do that this week.
Thanks


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## worldgeezer (Nov 26, 2018)

Well, life does have a way of intervening …

To add a layer of wood to the back, I found some poplar here locally, sliced it to just under 1/8 thickness, (hide)glued it to the back, then sanded smooth and coated with three layers of shellac.
After about two weeks, I realized that this might have straightened the cupping somewhat, but was no guarantee of permanence. Thus I removed several of the birch triangle pieces (in the ribbon on top) and inserted 2" bolts through the substrate into spines on the bottom, then replaced the triangle pieces. This flattened the top, and has held over the past several weeks. The spines on the bottom are not visible unless the table is turned over.

Finally have the top finished. 6 coats of shellac. I'll do several more fairly soon when I have it in the walnut frame.
See photos.


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## worldgeezer (Nov 26, 2018)

Paul,

But first, I need to find a way to get Granddad's text on to the underside of the substrate.

On 02.03.2019, you wrote

*quote:* By all means take pictures of the writing. There are ways to transfer printouts of it onto wood.

I'm at that step now.

What would you recommend?

I have multiple pictures of Granddad's original writing, so the wording isn't a problem.

I tested a separate piece of shellacked poplar, and found that I can write on it using a black sharpie. (My handwriting isn't up to that level of consistency to do a good job of it, though).

Thanks for suggestions.

see photo of handwriting


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## shipwright (Sep 27, 2010)

I'm now t an expert on it but I know I have seen several examples of laser printed pictures and lettering heat transferred onto wood. Do some YouTube research. There are some examples right here on LJ

I just did a quick search "Laser printed text to wood"


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## Lazyman (Aug 8, 2014)

You could also just attach a printout to the bottom much like some furniture manufacturers do with their labels. Some glue them on others just staple them.


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## worldgeezer (Nov 26, 2018)

Thanks for the suggestion Nathan. I thought about it …. however I wanted the text to be (more) permanent. See next.


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## worldgeezer (Nov 26, 2018)

I also realized that it was likely that the piece of paper would get detached.


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## worldgeezer (Nov 26, 2018)

Thanks for the various suggestions. Interesting to find the various ways that people have addressed this.

Searching around L'jocks site I landed on this link
https://www.lumberjocks.com/TheCrafsMan/blog/68650

and this YouTube video:





I followed his instructions, tried it out on a scrap piece of poplar … worked very well.
I tested it a few times, and learned:

print the text in bold, this gives more ink(toner) to absorb in to the acrylic.

I used PAINT to reverse the text. (And lost the underlining of the section titles, but no great loss).

Rather than printing and affixing an entire page, I trimmed each section down to about a .5 inch outline.

I brushed on the acrylic, then laid down the trimmed sections, came back several days later to work off the paper. It was harder to do, because more of the paper embedded itself into the acrylic as it dried. I found that I needed to work the paper off the wood, then let it dry so I could tell where a thin whitish / paper film was still there. After several tries, I got it all off.

If I do this again, (which is likely), 
1 I will trim each section of the printout so it has a smaller margin,that is, closer to the text. 
2 trace each piece of these pieces of paper onto the wood, thus to give an outline of where to spread the acrylic. 
3 experiment with thinner paper to see whether this makes it easier to remove the paper 
4 wait no more than about 2 hours before rubbing to remove the paper, so that the acrylic hasn't yet permanently dried.

Here is a picture of one of the three sections as it now is:










There is a video of a similar process at this link:


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## shipwright (Sep 27, 2010)

Well done!


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## worldgeezer (Nov 26, 2018)

Greetings, I'm restoring another one of Gramp's coffee tables.
It appears that I will need two thin strips (like about 1/16 wide, no more than 1/8 thick) of ebony.
Previous experience with ebony suggests that it's quite brittle, so …
So any suggestions on how to do that?
(I only have a table saw to work with … no bandsaw).
The only idea that comes to mind is to "sandwich" ebony between two pieces of hardwood (should these be lightly glued together?), then use something like Rocker's Thin strip jig to make the cuts. Peel off the two "sandwich" layers and hope for a smooth result?
There may well be better ways to do this…
Thanks,


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## shipwright (Sep 27, 2010)

How wide does it need to be? 
IMHO thin strip jigs are completely unnecessary. You can cut a sixteenth next to the fence if you use a zero clearance insert and an appropriate push shoe. An eighth is even easier.
You might also consider using dyed veneer. Ebony is endangered, expensive and difficult to work with.
Just a thought…


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## worldgeezer (Nov 26, 2018)

Just now seeing your post above, Paul.
Hmm. Good question.
I certainly am not obliged to use ebony - but liked the contrast in color.

The other woods (along with the ebony) he used on this table are poplar, brazilian rosewood, walnut, birdseye maple.
In the attached picture, the "curve" referenced in the other reply is centered along the whorls in the middle section of the two zebra wood strips.

Like the previous project (restoration completed middle of 2019), the plywood substrate had a layer of thin paperboard (white facing over gray paper), then in various places, two or more layers of masking tape. The table had gotten wet somehow so liquid essentially loosened whatever glue was used - quite likely, common wood glue for the 70"s. The veneer had come loose in other places as well.
It's now all stripped down to the substrate which has been lightly sanded. Next step is to clean all the paper, masking tape and old glue off the underside of the various veneer pieces. 
I'll use old brown glue when I put it all back together.
Cheers,
eric


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## shipwright (Sep 27, 2010)

If you have all the veneer off and all you want to do is straighten the edge of the zebrano, why not just reassemble and trim the outer edge of the substrate to suit the new 1/16" to 1/8" size of the veneer after glue up?


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## worldgeezer (Nov 26, 2018)

as in the picture above, the zebra wood is in the middle, both (long) sides are filled with about 2" of various pieces of walnut, poplar, brasilian rosewood between the zebra wood and the outer edge of the substrate. If I trim the zebra, then this leaves a gap, because those 2" of various woods actually wrap around the zebra.
thanks


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## shipwright (Sep 27, 2010)

I understand, I thought you had all the veneer off. If so just adjust the border and move it in the sixteenth is what I meant. Then the whole top becomes a smidge smaller and you can trim the outer edge of the substrate.


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