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15

I find this really hard to believe.. if dropping a piece of lumber did 'relieve stress' then there should be no stress in it by the time it makes it to your local lumber distributor-- it's been dropped numerous times between tree and your shop. Are we sure the original publish date of this article wasn't April 1? ;)


15

Your pallet board may not be worth the effort, but there are several techniques that you can try to salvage any warped board. The optimal solution will vary depending on how you intend to use the board. Wikipedia has a nice primer on specific types of defects in wood which fall under the blanket term of warping: bow : a warp along the length of the face of ...


15

A common solution is to alternate your clamps between top and bottom: Another solution is to clamp boards down across the panel as Drew suggested, although an even better variation on this solution is to use cauls, which start out curved but evenly distribute the pressure across the surface as they are flexed flat against both sides of the panel. Read more ...


14

Steam bending would be your only option. Wetting the fibers and allowing them to bend and twist. It might not work, but there is a chance. Not using a moister measure, you will just split the wood where the stresses get to great. On top of that, you will have to redry the wood back to where you need it and you will need to keep a lot of weight on it so ...


12

The other answers have covered how you can bend the wood, but one thing they left out relates to the length of the wood. The following applies to some other defects too like bows. You mentioned you have 6ft boards, but you don't say what your final board length will be. If the length will be shorter than 6ft, then it would be advisable to cut them to ...


11

I always clamp jointed boards with some good, straight hardwood boards across their faces. This way, you'll use long clamps across the face of the jointed boards to keep your joints together, and shorter clamps to clamp your truing boards to the face. Use a pair of boards with the work piece between them. When it sets up, it should not be bowed at all.


10

There's a couple of ways to do it Create an "in feed" and "out feed" fence for the table saw fence (see http://www.woodworkingtips.com/etips/2005/01/28/wb/). The infeed is slightly narrower so as the work is passed through it, it cuts the board and should come out flat on the other side, assuming the outfeed is parallel to the blade. Secure the warped ...


8

You can get this flatter certainly, but you may not be able to get them totally flat or to get them to stay that way permanently — wood that has bowed can show a tendency to want to return to that shape. One method is to wet the cupped side and put the wood out in the sun to dry. A variation of this is to wet both side but have the wet side sit on grass ...


7

This is not really an answer but a large comment that could point out several pitfalls that could have brought you to this point. I am not sure of the best advice for your situation as the warping looks significant. Like discussed in comments I think you might be better off starting over and paying attention to points below. Knots and Pith Depending on ...


7

If you do not need the exact thickness of the board you could just run it thorough a planer and or jointer to flatten it out. But if the board thickness is exactly what you need then I have seen a jig, it was a few years ago, that used steam and weights to straighten boards out, but this seems like a bit of overkill to me to create such a large jig (...


7

Bending using heat (usually steam) is one of the only ways to bend wood reliably. But, when a board twists as it dries that is usually not permanently fixable because the wood may have 'taken a set'. So while you could steam, bend back to perfectly flat and hold it there until it has cooled, and it may stay that way initially, it is likely to have a natural ...


7

The strips you secured to the bottom are the cause of the warping. The main boards can't expand and contract because they are fixed to the strips at a few points. If the boards were just glued to each other then it would expand/contract as a single panel. This is the same problem you face with tabletops, hence the need for connections that allow movement. ...


6

Stress is only relieved by either bending or cracking. If dropping cracks the wood in the right way, then stress is relieved. You could potentially relieve internal stresses by encouraging it to bend in the right way, but that seems risky - how do you know which direction to go, and how far?


6

I know cheap construction 2x4s can warp There are multiple possible causes for distortion in a glued-up panel like this. Often more than one of them are to blame, although there may be one major culprit. I suspect that's the case here. Since your tabletop ended up 'in wind' (twisted) and didn't cup or bow I think the wood itself is likely to be mostly or ...


6

MDF is practically purpose-made for this application. It is very dimensionally stable, one of its prime selling points. And while it's not as stiff or strong as ply it is as a rule more stable these days (because of the falling standard of plywood, while MDF is easier to make to a reasonable standard consistently). As often mentioned MDF can bow under its ...


5

We have to be careful in advising you here since what you mean by "warp" may not match the commonly accepted definition. Some people use the term generically to refer to boards that aren't flat along their length, rather than to describe a specific kind of curvature to which the word more accurately refers. You can sometimes improve on this by dampening one ...


5

Your best 'chance' is using moisture. Basically getting the wood 'wet' and straightening it, then letting it dry straight. Some woods and small bends might work with wetting/moistening the board. However, steaming the board is likely to be the most successful on the widest ranges of species and quality. It also is unlikely to be worth the extra effort vs....


5

I have tried to straighten a wood screen door with steam with very little improvement. I then forceably bent it well past straight, 1 1/2 inches in center of the 7 foot span. Then saturated it with linseed oil and carefully heated the board with a propane torch. It is holding it's shape after a week.


4

Common wisdom is that if you have access to a jointer and planer, you will joint the board on the cupped side to flatten it, then use the planer to produce a smooth edge on the opposite side. If you don't have a jointer, there are some jigs available that can attempt to replicate a jointer's function on just a planer. If you don't have a planer, well, you'...


4

Is the humidity in your garage the same as the humidity in the room where the dresser is kept? You can start with a board with 0% moisture content, but regardless of the finish you put on it, it will take in moisture until it matches its environment. I know you can't always do this, but the best way to finish out the seasoning on your lumber is to put it in ...


4

Adding to Graphus's answer, you can also cut the board down the middle run them through a jointer and reglue them back together. If you can flip one side over for the join, you will reduce the max bow it is capable of.


4

MDF is much more likely to be flat and is relatively dimensionally stable - however it's not overly strong when running long unsupported distances. If the pelmet is attached at its top along the length then it should be fine. If you plan on only attaching it at the ends it will probably sag over time. (...usual concerns about formaldehyde off-gassing and ...


4

In my view this is a question of "Do I control my materials or do they control me". Your concern that your warped pieces may not meet well is valid. Every project should begin with a plan for what you intend to achieve and then constructed accordingly. Your idea in the fourth paragraph is a good strategy. Begin by assembling the framework for your boxes ...


4

Are you familiar with how the wood fibers are aligned in a tree? They (mostly) run from top to bottom and are bonded together with lignin. If you used the 'B' method the wood fibers would be running into and out of the page when viewing your diagram. This would make the bond between neighbouring fibers short and weak - the cover would snap easily. This is ...


3

Essentially: No. You make slabs flat by removing wood to obtain a flat surface, by planing or by using a carriage-guided router or by machine-sanding or some combination of these. Sometimes you can reduce how much wood is lost by dividing into smaller pieces and gluing back together later, but making the grain match up again is a challenge. See the related ...


3

If a board were to lose its internal stresses by dropping or for any other reason it would take on a new shape and be warped, twisted, curved and in need of reshaping. If you have ever ripped a thin strip from a wide a board and ended up with a something resembling a steam-bent shovel handle, you have witnessed the process of relieving stress in wood.


3

I had a bed rail twist on me once. I tried to wet it and then dry it while it was held flat. It didn't work. What did work was kind of embarrassing. I slipped one end into the hardware on the headboard, rotated the footboard until it would slip into the hardware on the other end, then rotated the footboard back into the normal position. That is, I used ...


3

No one has mentioned your jointer technique. If the jointer fence is not perfectly 90° then any small deviation get multiplied by the number of boards you have and you get a curve. The solution to this is NOT to try to get your jointer fence exactly 90° (although close is good). Instead, lay out your boards how you want them to be glued up, and draw a ...


3

The panel is curving because the support strips running perpendicular to the panel boards are flexible. The panel boards have dried and shrunk while the support strips remained unchanged in length. If the support strips were stiffer, the panel would not curve, but instead, the panel boards would be splitting. It the ambient moisture conditions were ...


3

He thinks that the bed slats might warp if I don't use a sealer. A 'sealer' won't make much or any difference to this once the slats are fixed in place and in use. I use quotes above because the idea that we seal wood with a finish is widely misunderstood. Various finishes do protect the wood's surface from dirt to various degrees (even a thin application ...


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