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the wood from hell..the wrong information provided...and natural wood behavior

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Forum topic by M2D2 posted 06-17-2018 01:47 PM 1634 views 0 times favorited 15 replies Add to Favorites Watch
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M2D2

26 posts in 173 days


06-17-2018 01:47 PM

Hey Folks,

First…can I get POSITIVE replies ONLY….not you should have done this or that..or wtf…and so on..but solid positive fixes…don’t need trolls, need solutions. Time is pressing, I only have a few days to wrap it all up.

I have 2 separate projects on the go. I’m looking for confirmation and if possible complete explanation alternatives…this might be a touch long.

#1. Dining Table – from Wood from hell.
- its spalted maple, it started at 2 inches thick, and after flattening its down to 1 5/8 or 1 and 3/4 (can’t remember exactly)
It has developed a cup on the 1 side that I had sanded to 120G. The bottom side shows the reverse with bowing, the cup is 1/8th to 1/4 deep in the centre.

The table is 48” long x 25 1/4 inch narrowing to 22 1/2 at the other. So its not overly large. I can put angle iron on the bottom to help stop the cupping from continuing ..

Question a) if I put the iron angle on the bottom, will it indeed stop the cupping.
and b) if I use the cupped side for the top side, can I put epoxy to level it, with the epoxy flaking or chipping away.

#2. The desk.

The desk is fairly flattened, but has deviations and subtle valley’s. (note: I had a neighbor who was in the “skilled trades”, advise me that I should start at 36G and go up, and that I could sand in any direction, the counsel was WRONG!. It took hours to get the tool marks out, and so on…anyway..)
I have started finishing it…with danish oil…but I was thinking while I’m ok with the subtle deviations in the surface not being perfectly flat, if I put some clear epoxy on top to further level the surface…will the epoxy bind…granted I may have to scuff sand the danish oil to allow for some “BITE” for the epoxy to adhere to.

Look forward to the responses….ugh…heartwood…from hell.

Thanks so much for your POSITIVE ideas and SOLUTIONS.


15 replies so far

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M2D2

26 posts in 173 days


#1 posted 06-17-2018 01:48 PM

Here’s the desk piece…

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lew

12267 posts in 3873 days


#2 posted 06-17-2018 02:13 PM

Perhaps rip it it into more narrow boards, joint the edges and re-glue. You’ll loose a little width, however.

-- Lew- Time traveler. Purveyor of the Universe's finest custom rolling pins.

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jmos

858 posts in 2487 days


#3 posted 06-17-2018 04:12 PM

I imagine you could coat either in epoxy to level, but do you want that look? It will look a lot like a bar top. Not a look I’d want in my dining table, but everyone is different. I can’t comment on the epoxy adhering; I’d check the manufacturers info on that. I agree it would be a concern.

If the desk isn’t too wide, and the top if fairly flat, you might be able to find a shop with a drum sander or planer that could give you a nice flat surface. Very possible you could find a shop that could handle your table top too; 25” isn’t that wide.

It may be possible to muscle the table top flat by attaching to the frame, or some batons (like the angle iron you mentioned), just be sure to allow for movement along the width. You could always try this first and see how well it flattens. That’s a lot of cup to pull out of a thick board over a 2’ width.

I’m with Lew, I’d rip it down, joint and plane each piece flat, joint the edges and re-glue. If you keep them in the same order, the glue joints won’t be too noticeable. You will lose some width, but a lot less thickness than trying to flatten that cup out.

-- John

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M2D2

26 posts in 173 days


#4 posted 06-17-2018 04:43 PM



”...positve… don t need trolls…”

A snowflake…

- fuigb

one word. FAIL!

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pintodeluxe

5741 posts in 2931 days


#5 posted 06-17-2018 04:52 PM

Angle iron will probably flatten the table okay. Just be sure to mount it through slotted holes to allow seasonal movement, otherwise the wood will eventually crack.

-- Willie, Washington "If You Choose Not To Decide, You Still Have Made a Choice" - Rush

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Dustin

551 posts in 858 days


#6 posted 06-17-2018 04:56 PM

I’m also in Lew’s camp on ripping and re-joining. You might lose a little thickness, but you can re-joint and plane the boards at this time, too. If you go that route, be sure to treat both the top and the bottom identically, otherwise moisture may end up escaping unevenly from one side, causing more warping. At that point if you wish to use angle iron, I’d say have at it; just remember to elongate the screw holes to allow for expansion/contraction.

-- "Ladies, if your husband says he'll get to it, he'll get to it. No need to remind him about it every 6 months."

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M2D2

26 posts in 173 days


#7 posted 06-17-2018 05:28 PM


I imagine you could coat either in epoxy to level, but do you want that look? It will look a lot like a bar top. Not a look I d want in my dining table, but everyone is different. I can t comment on the epoxy adhering; I d check the manufacturers info on that. I agree it would be a concern.

If the desk isn t too wide, and the top if fairly flat, you might be able to find a shop with a drum sander or planer that could give you a nice flat surface. Very possible you could find a shop that could handle your table top too; 25” isn t that wide.

Thanks to you and Lew…i’ll give it go…appreciate the info

It may be possible to muscle the table top flat by attaching to the frame, or some batons (like the angle iron you mentioned), just be sure to allow for movement along the width. You could always try this first and see how well it flattens. That s a lot of cup to pull out of a thick board over a 2 width.

I m with Lew, I d rip it down, joint and plane each piece flat, joint the edges and re-glue. If you keep them in the same order, the glue joints won t be too noticeable. You will lose some width, but a lot less thickness than trying to flatten that cup out.

- jmos

Thanks guys really appreciate the advice…and solutions :)

View Woodknack's profile

Woodknack

12331 posts in 2498 days


#8 posted 06-17-2018 05:29 PM

Until you understand why it cupped, any remedy is a wild guess. If you rip and reglue it may cup again. Usual causes are unequal air exchange between top and bottom, like setting the unfinished panel on your tablesaw or finishing only the top. Or it could be the wood was improperly dried.

-- Rick M, http://thewoodknack.blogspot.com/

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fivecodys

1128 posts in 1754 days


#9 posted 06-18-2018 03:25 PM

I would rip into 3-4 pieces, joint, plane and then re-glue.
Finish the bottom and top the same or may just cup again.

Let us know what you decided and the results please.

Chem

-- There' are two theories to arguin' with a woman. Neither one works.

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msinc

497 posts in 621 days


#10 posted 06-18-2018 03:39 PM

One thing to think about, and don’t get me wrong I am all about the rip and re-glue thing, but you might have to flip every other board and lose the continuity of the grain if the cupping is due to stress. Might not look bad and might still be very acceptable. If the wood meters good and dry, but still wants to cup then it could be just stress in the wood and forcing it flat wont be a very suitable solution. I have found that when wood has a lot of stress it has to “release” some how.
As far as angle steel bolted to the bottom to “pull” the cup out, I have tried something similar and got it flat only to have the top crack along it’s length because of stress. Again, it could be either cause….I have seen a lot of 2” wood cup as the moisture was leaving it. End problem/result really is the same though…it’s cupped and it’s not wanting to straighten up.
When you say you only have a couple days to wrap this up it seems like you have two options. Either start ripping it and get the glue ready or start building a router sled. However, if the moisture content isn’t correct then you aren’t wrapping anything up in a few days. Good luck…you might need it.

Edit: It occurred to me that I worded it wrong about stress…if a board warps due to stress then the subsequent warping was the “release” so to speak, or at least most of it. Now, you take a steel angle and force it back straight and lock it down you have reintroduced the stress back into it. Often, in so doing the wood now has to find another way to release it, so it might crack or warp some other way. I hate stress in wood.

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jmos

858 posts in 2487 days


#11 posted 06-18-2018 03:44 PM

Another option is to make some kerf cuts on the bottom. These would be cuts through a portion of the thickness (maybe 3/4 of the total thickness), and they would make it much easier to pull the board flat. It would require some sort of edge treatment (banding, breadboards…) on the short ends to hide the kerfs, but it might be worth considering. You wouldn’t loose any thickness or width.

-- John

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Andybb

1225 posts in 721 days


#12 posted 06-18-2018 03:53 PM



I would rip into 3-4 pieces, joint, plane and then re-glue.
Finish the bottom and top the same or may just cup again.

Let us know what you decided and the results please.

Chem

- fivecodys


+1 and just to be sure, if you have the energy try msinc’s suggestion of reversing the boards.

-- Andy - Seattle USA

View Woodknack's profile

Woodknack

12331 posts in 2498 days


#13 posted 06-18-2018 05:27 PM

edit; nm

-- Rick M, http://thewoodknack.blogspot.com/

View Monte Pittman's profile

Monte Pittman

29792 posts in 2456 days


#14 posted 06-18-2018 05:42 PM

My experience, filling with epoxy will make the cupping worse. I doubt that you will like the results.

-- Nature created it, I just assemble it.

View OSU55's profile

OSU55

1834 posts in 2107 days


#15 posted 06-18-2018 07:37 PM

More info on how you prepped the lumber and did the glue up would help. Did you check moisture with a meter? If you rip and redo, but follow the same process it may result in the same problem.

It is way too much cup to fill with epoxy imo.

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