Can this wood be saved?

[vaddoc]

Dear all

 

I have quite a lot of very nice maple sheets. They started off very flat and ended up massively warped. Any suggestions if these can be saved and how?

I am thinking soaking for a couple of hours in water and compressing.

 

Vaddoc

 

 

[lehmann]

Pre-bend planking:  looks like a feature you should have paid more for. 

 

I would just wet the areas with the hardest bends/twists to avoid creating fuzzy grain and water stain.  Maybe heat with hot iron.  The longer, slower bends should straighten out as needed, although if you're planning to rip into strips, they could be awkward.

 

What is the intended use? 

 

[Jaager]

Which component is this intended to be used for?

It is too thin for frame timbers  - except for miniature scales.  In which case - not safe even if flattened.

Deck planks - not safe.

By not safe - what I mean is that the wood is showing where it wants to go.  Even if you flatten it, it will "want" to go back to this shape.

Hull planking - already a good start for conforming to frame contours  - it may prove to be  a challenge to rip if it can't be pushed flat as is.

 

If you still wish to flatten, rather than a water soak, try steam.  A steam iron or hand steam generator clearer and a lot of weight.

[vaddoc]

Many thanks to both

 

This is left over wood from planking my current boat. I may have made a slight mistake calculating how much I needed!

However I liked maple very much so will use in planking a future boat.

[Bob Cleek]

It appears that the material pictured is veneer, rather than sawed wood. Veneer is cut from a rotating log by means of a sharp blade. It's like an apple peel, rather than a cut piece. As a result, when veneer "relaxes," or re-absorbs moisture after kiln-drying, it will look exactly like the wood you've pictured. Sawed wood strips will hold their shape far more reliably, as they are cut with the grain, rather than being peeled from the log by slicing across the grain and then flattened out. In short, it is under stress from the git-go.

 

If you can "moisturize" it by increasing its moisture content (which means increasing the moisture throughout the piece, not just getting it wet on the outside,) it can then be put in a press of some sort and left to dry some. That should flatten it pretty well, although it will always want to "go its own way" if it reabsorbs moisture when the humidity rises. That may not be a problem if it is by then well-fastened, but it's hard to be sure. The forces generated by moving wood are surprisingly high. For this reason, I only rarely use veneer-cut wood on models and then only small pieces that are well secured. 

[vaddoc]

Thanks Bob

 

I honestly do not think it is veneer. I bought from a well known high quality source and it is almost certainly sawn timber. At 2 mm thickness it is unlikely to be veneer and maple veneer is not really used very much. I think that either the tree had a hard childhood resulting in grain abnormalities or I stored it improperly.

I ll thoroughly wet a sheet when I find the time and compress it, maybe it will flatten. I ll post the results

 

 

[Bob Cleek]

A close look at the end grain directions should reveal if it's sawn or peeled. If you can add heat to the equation, you may be able to bend it back to flat again. Simply getting it we won't likely do much. Given the thickness, it should be capable of being bent to where you want it. Myself, I'd keep it, stored flat, perhaps with some weights on top, and see how it goes. When it came time to use, I'd heat-bend it to where I wanted it to go. 

[Jaager]

It is likely that it is heat and not water that allows lignin bonds to reset.  Water plus heat produce steam, which is more efficient in heat transfer than dry heat - seasoned wood has air spaces - insulation like. 

[vaddoc]

Dear all

 

I threw the sheets in the bathtub and soak them in very hot water. Then I took them to the garage, flat on the work bench with a sheet of particle board on top and whatever heavy items I had laying around pressing down. I repeated this cycle twice.

 

Much improved situation, some sheets better than others. Some are dead flat, others have one edge straight and the other a bit wavy, others still a bit wavy. They are all however usable now.

[Thiscout]

On 11/17/2019 at 11:52 AM, vaddoc said:

Dear all

 

I threw the sheets in the bathtub and soak them in very hot water. Then I took them to the garage, flat on the work bench with a sheet of particle board on top and whatever heavy items I had laying around pressing down. I repeated this cycle twice.

 

Much improved situation, some sheets better than others. Some are dead flat, others have one edge straight and the other a bit wavy, others still a bit wavy. They are all however usable now.

they will not be perfectly even

[Keithbrad80]

If you still have them and need to flatten them I would wait for summer. What I do is soak them with water so they are completely soaked through. Then cover them with something super heavy but something that puts pressure across the entire surface evenly. Bricks work well for me. Cover them with plastic wrap but leave some vents for moisture then leave them out side in the sun for a week or two. They should be flat enough to cut afterwards. 
 

Bradley

[Charles Green]

At least you still have the wood.  It looks like it tried to get up and walk away!  

 

 I have worked on ornamental boxes built with sides of 1/4 inch maple.  To prevent warping after construction, I have glued two sheets of flat 1/8 inch together, making sure the grain in each piece runs in opposite directions.  Each piece cancels out the other's tendency to warp. 

 

After your efforts to flatten your wood, it will still tend to want to wander.  As wood is sliced to ever thinner dimension its rigidity is reduced.  At some point, any internal stress will overcome the wood's ability to resist and the stress will take over.  If you need to use the wood in sheets, getting it as flat as possible and then gluing it up as above may allow you to use much of it, albeit for projects requiring a thicker cross-section than what was originally intended.  Single thickness, narrow strips may be used if they are well supported and glued and/or pinned down solid.  

 

It is not water - but the heat in hot water - that allows warped wood to be reformed, or straight wood to be bent.  Industrially, steam-boxes are used, since that is the most efficient way to heat large pieces or large amounts of wood for bending, but for hobby-size pieces, dry heat will work just as well.  I have an idea - I have never tried this - but do you know someone with a dry-mount press?  These presses bond paper or fabric based art-work to a rigid substrate by heating and pressing the two together with a sheet of heat sensitive adhesive in between .  The one I have is 18 x 24 inch and provides heat from 180 to 325 deg. F. (82 to 163 C.)  Larger art-work is handled by passing it though, section by section.  Your sheets of maple could be passed through a dry-mount press in the same manner.  The press would provide all the heat and pressure needed for thin sheets of wood.  With clean, non-resinous wood, I would allow my press to be used in this way - I can't speak for anyone else! 

    

  

[vaddoc]

So I think I should provide an update!

Despite my efforts, the sheets never became really flat. Now these sheets can be easily replaced but I thought I d try and rescue them/ The last efford was wetting them thoroughly and leaving them compressed between flat surfaces. 3 days later, they had become mouldy! Bottom line: Wood in this state cannot be salvaged.

1 hour ago, Charles Green said:

It is not water - but the heat in hot water - that allows warped wood to be reformed, or straight wood to be bent. 

Actually, water does dissolve some bonds and allow some wood movement. From then on it is indeed heat that softens the lignin but moisture dramatically decreases the temperature threshold for the wood to become soft.

[Keithbrad80]

I vote hold onto the wood, if you still have it, for one reason only, spalted wood. If you do any other wood working and want a really incredible piece of wood spalted maple looks really cool. It’s basically a fungus that grows within trees and leave really a nice pattern throughout the wood. If you don’t do other wood working I guarantee other wood workers would buy it from you. Keep the maple in a plastic bag until it reaches a high humidity and moisture content, leave it in the bag for a while maybe a few months, check it periodically. Here what it will look like once spalted: 

 

Bradley