Wow, what a jokester

Glad it helped

Internal stress of the crappy board will only resurface once the board dries out again.

Glad to hear that!

Very unlikely it would work on a wood floor. If the floor has thick boards they could be retified on a planer.

Did it work?

Uncommon Redesigns yes it did! It was early winter when I did this 2 months ago. So I wasn’t able to use heat like in the video, so I tried with wiping on some regular cold water to the board with a rag (to the bow side facing down towards the floor) and added weights on top. It actually worked so well that it bowed upwards. So I flipped the board and repeated the process, wetting the newly bowed area with less water this time, facing it down and placing weights on the top. Now it’s perfectly straight, and did not have to use any heat. Just experiment with the right amount of water for the wood you are using and let it air dry. My process took about 3 days overall and it turned out flat enough to touch up with the hand plane, or even to use as is depending on how perfectly flat it needs to be. The total weights I used was just some spare weight plates for bench press that I had in my room - total of 100lb.

@@Geoff Thanks for sharing that...I wonder if a heat gun would make any difference on the wet wood. I've got the same thing now- fall in NY...not enough sun to help.

@@sharit7970 Let me know how your project turns out. The plywood I flattened has been indoors since I first did this process, 2 years ago now and it has kept its shape. It’s currently in use as a book shelf and my piece is still flat after 2 years. So as long as conditions remain fairly stable, the wood should remain the same. Steam heat would work best, so a heat gun would probably evaporate that moisture too fast or dry it out and make the cup worse on that side. But I have seen people wet and wrap sections of wood in a cloth and foil and go over the cupped section with a clothes iron so that’s also an option if you’re wanting to use heat. I like the way shown in this video, of just allowing ambient temperatures and weights/clamps do the work. Slower process, but simple and less setup work for me. I just have to keep an eye on the work and the internal moisture seems to equalize itself overtime, maybe making it more stable, i dont really know. I’ve since seen old-time carpenters do the same (just water and board flipping, resting on wood slats indoors -no heat) and it works for them. I’ve seen some major cups come out very flat this way. I was suprised.

@@Geoff Thanks for the response! I've got this project on the back burner now... too many other projects. I tried wetting and weighting the piece, [a drawer bottom] but it didn't work. I'm going to note your comment here for when I get back to it, and I'll try to remember to let you know what happens. Thanks again!

Most of the time I would say no as most tables are normally made from 6-8 individual boards glued together rather than one slab of wood. Table cupping / warping can be fixed if the cause is due to the horizontal support rails being warped in that case just replace them but not all tables have them. Sometimes it is possible to repair a thicker table (over 3/4" thick) surface planing / milling with a CNC bed or you can use a router sled but you lose at least 1/4" of table depth in the process.

I saw someone in a video used a heat gun but it didn't work but you may get lucky.

@@brieftodo Did they wet the wood first...do you remember?

I saw one guy trying to do the same with blow heaters but it didn't work so I guess you'll have to be patient and wait for Summer.

Good luck!

@@brieftodo It did work quite well thanks. I know I didn't do it exactly the same as you said and I was going to pour some water over them if it hadn't worked dry, but then we had a couple days of rain and that seemed enough to have made it work. After taking the trailer off them and standing them up, they were pretty flat. I wouldn't say what I did has made them dead flat, there's a slight bend still, but for my project of needing some 2ft squares cut off the sheets, it's certainly done the job and saved me having to go and buy more new ply. I will definitely remember your method for next time I get this problem. 🙂👍🏽

No. You can't. It's disallowed.

It is super variable sometimes it does and sometimes doesn't. I recommend using it where it requires to be screwed down.

After scouring the internet, I didn't find what I needed. What I came up with is to use a router to cut a slot in the plywood. The slot is on the concaved/hollowed side, perpendicular to the direction of the curl. The depth should be about half the thickness of the plywood. Then you hammer a strip of hardwood into the slot. The strip should be a few thousandths of an inch too wide for the slot. The fit should be so tight, you don't even need glue! Repeat as necessary, every so many inches from the previous slot, in the worse part of the curl, until the plywood is flat. If the curl is complex, you can criss-cross previous slots, but wherever you cross another slot, you can end up with a slight bump around the intersection. A good sharp card scraper can alleviate that. I came up with this to fix the warp in my bandaw sled. You can't have a back fence on a bandsaw sled. After cutting the sled in half, the plywood curled and one corner stuck up half an inch. I lived with that for a long time, then finally tried this idea. It worked brilliantly.

@@mildyproductive9726 The hardwood strip goes the full width of the plywood? I might have to try that. I built a bed platform for a SUV camper out of radiata pine and it is frustratingly warped. The trick in the video worked OK, but the middle is still ~1/4-1/2" higher than the side.

@@scotth5503 yeah, but the curl in mine wasnt a bowl shape. It was simpler. You might have to get more creative!

Harder woods are less flexible so less chance of success but no harm in trying.

You're welcome

Soapy water

Unlikely but you could give it a try

@@brieftodo I mean carrom board