Wood warped after cut

Hi,
I am tinkering around with various hardwoods. Some of them unknown (as is the case with this piece of wood). I decided to use thick basswood for my initial settings. The only thing I edited is the pass count. I chose three passes. My 1/4 inch board remained flat during the whole cut (about 10 minutes), but the finished coaster came out with a warp. As I am looking at the GF bed, the coaster shape to and bottom curled slightly up. My cuts in these areas did not go entirely through the piece. Any thoughts on this would be appreciated.
JSM

1 Like

Wood will do that - it’s not naturally flat, and it’s got moisture in it that’s removed when it’s hit with the laser.

It’s likely that you can wet the piece entirely and place it between two flat objects with a weight on top and get it to go back into a flat - but as a coaster it will likely absorb water and re-warp over time.

If you’re going with straight wood I’d suggest a good sealant!

6 Likes

Yeah plain hardwoods aren’t a good fit for coasters. Plywoods are much more stable. Try your hand at Baltic birch maybe, I’ve been using BB coasters daily for over two years, they look brand new. I finished them with danish oil and they’ve been perfect.

7 Likes

Isn’t that a pain in the butt? I avoided ply simply because I thought plain wood looked so much better. It figures, huh? It’s like a cruel joke. Lol. Thanks for the help.
JSM

1 Like

You can use plain wood as you can take out any warp by pressing it while damp between two hard flat surfaces (like tile) clamped or a lot of weights, I also put cotton cloth at one layer each side to allow the water to escape. At that point a sealant should do the trick.

3 Likes

I’ve had good success in preventing warping by layering two thinner pieces of wood using Gorilla glue and overnight clamping—with the grain rotated 90 degrees between the two pieces. :sunglasses:

For example…

4 Likes

Nice. Never thought of that. Thanks.

1 Like

@JigSawMan messaged me to ask about my “L-coaster settings” from 2018. Here’s what I told him…

Here’s what I had saved for my Glowforge Basic…

You can see a couple of small holes to the upper right of the “L” coaster that I used to “dial in” the settings that I ended up using. Your mileage may vary… :sunglasses:

BTW: In my experience you cannot depend upon the Glowforge GUI to save your work! That’s why I grab a screen-shot like that to remember my settings for later.

2 Likes

I have a small notebook that I write all my different settings down in. Reality is that computers crash. Mine, google, glowforge, etc. My house can burn down too (it has LOL), but at least I have it backed up one other non-computer place and it is on me, not someone else. I believe strongly in personal responsibility.

2 Likes

@Pearl: I wish I was so organized! What’s “good enough” for me is a screen-shot JPEG showing the Glowforge settings with the same name as the SVG file—all in the same folder.

BTW: I literally have every file and email that I’ve ever created or received “spinning” on my personal computer. (And I’ve been “on-line” since the late 1970s.) Luckily the decreasing price of storage and increasing speed of PCs makes that doable. But for that to work one needs reliable backups. The Cloud has made that even easier—no more hard drives in the safety-deposit box. :sunglasses:

1 Like