Need help with wood sourcing... and learning about wood

Of all the species oak makes the biggest mess, but that does not keep me from using it, it just colors my expectations. No matter the species the hotter and slower the pass the less the grain shows up. Going colder. faster, and especially multiple passes make the grain show up stronger. If you are using a filter only MDF will fill it faster.

After the first month I had been doing a bunch of oak plywood and checking my exhaust it looked like burned cotton. On close inspection it was all those oak fibers that everything around them was burned and they broke loose rather than burning themselves.

I won’t duplicate some of the other advice but I didn’t see this mentioned - when using manufactured wood products, the bonding agents differ widely and some will offgas toxic chemicals when lased It’s important with plywood or MDF to make sure the stock is safe for lasers. Other than always buying Proofgrade plywood and draftboard, I’m not sure if there’s an easy way to certify that.

The other thing I’ll toss into the ring here is an observation on types of wood. When I researched making a cutting board from scratch I read that woods which produce edible fruits and nuts tend to be safe. That includes most of our domestic species like Cherry, Maple, Oak and Walnut. However, some woods, especially those with high oil content or that are very fibrous, can release irritants when cutting with blades or sanding. Lasing is not cutting or sanding but until I know much more about material safety I’m sticking with the same wood species I’d feel comfortable eating off of. These turn out to overlap the Glowforge Proofgrade materials quite a bit - Maple, Walnut, Cherry. I may try Oak but as others have noted it is very open-grained and dense so I would expect getting a nice print on it would require much more experience than I have just now.

“Spalted” wood can be extremely pretty but the spalting is the result of fungus. It is highly prized by woodworkers but usually kiln dried before use. Even so, the fungus can cause irritation if inhaled. I’m not worried too much about the bits struck directly by the laser, but a little concerned about the bits next to the kerf that are ablated into the air.

Last thing in my “wood safety” pitch is that using wood other than Proofgrade leaves you a bit adrift as to settings. Things like moisture content can greatly affect how the wood is worked with metal tools so I assume there’s a similar variability with the laser. Same with knots. High power, high LPI and slow movement might cut in one pass but may also impart enough energy to start a fire. Test on scrap wood. Don’t be afraid to make multiple passes. Just as when working wood with metal tools, patience will reward you.

Good luck! I’m looking forward to seeing some of your work!

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White Oak is a very different critter than Red Oak (sometimes called Swamp Oak) both are strong but Red Oak is so porous that barrels made of it will leak. Red oak is more common and cheaper and thus more likely to be generic “oak”.

I’ve had very good experiences buying wood online from Bell Forest. They have a whole section with 1/8 thick dimensional lumber which would be good candidates for laser cutting. All the thicker common sizes too, of course. Click on any species to get a quick rundown of characteristics, a photo, and possible health issues. It’s not nearly as complete as the Wood Database someone linked to earlier but it does at least narrow down the exploration to a subset of species you could actually buy. Once you have a few candidates, look up those in the Wood Database.

When you do decide to buy a species you haven’t worked with before, be sure to get some extra to use to tune in the settings. I saw some great laser testing SVG files around here somewhere. Sorry, I don’t have a bookmark. But the gist was several patches of gray shades and different score lines. You use custom power and/or motion settings for each one. After printing you have a good idea of which settings to use for that species. I haven’t tried it yet but eventually I’ll take a break from making ear savers and then I plan to make several test panels for the woods I have in stock - Paduk, Purple Heart, Zebrawood, etc.

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Good point. There’s lots of variation within a family of species. (And some “families” are not actually related but just named alike.) I haven’t done enough wood on the GF to assess but I suspect that the cost of dialing in settings for non-Proofgrade stock makes the Proofgrade stuff more cost competitive for low-volume use.

Zebrawood looks great and very hard but one of the most flammable of woods. The only worse was "mahogany"but that is so many species and most are fine. In either case it is less a flame than a coal that does not burn out but eventually starts eating your work and your choice is stopping, and losing the piece or try to finish before the coal destroys the piece anyway. In either case you need to watch like a hawk.

I have linked this that I use, that uses a minimum amount of material and is good ballpark figuring. And bonus it is small enough that I keep them in a box for reference.

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Is it possible to dampen the wood before cutting to reduce the burning and “afterglow?”

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Thanks for this link to Bell Forest. This seems like a really nice resource.

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Oooh, thanks! All of the ones I found previously used shades of gray which I am guessing works great for variable power engrave. This one will allow me to use arbitrary discrete settings for each color. Very nice.

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Good to know. Thanks! My hope for most of the exotic woods was to laser cut inlay inserts rather than engraving so these will be milled down to 1/8". This requires a clean edge so either I’ll have to dial in the Zebrawood very carefully or abandon it as a candidate. At least I know going in what I’m up against.

For people who are going to be buying lots of wood you can get a 10% discount by joining The Wood Whisperer Guild. Doing that requires buying one of their projects, the cheapest of which was $30 ~ $40 if I remember correctly. That means you break even after $300 or $400 of wood, assuming the discount is your only reason for joining.

They have affiliations with a couple dozen other vendors, selling resins, abrasives, tools, wood, and other supplies with discounts ranging from 5% to 30% and of course there’s the TWWG community and content.

I’m not earning off the referral or anything, it’s just that 1/8" and 1/4" stock is expensive and if you are buying Purple Heart, Cocobolo or other wood that’s $20 ~$30 per piece, you hit that break-even point real fast.

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Previously:

I’ve pretty much moved to Ocooch and Kim Oberlin exclusively just based on price.

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Ocooch looks good but when I tried to find Kim Oberlin I turned up Facebook profiles and lots of people with Kim in their name at Oberlin.edu. I did find links to eBay auctions here in the forums. but they all led to dead pages and searching eBay for Kim Oberlin turns up squat. What’s the deal with Kim Oberlin?

I bought a bundle of 3" wide wood and never again, The three-inch limitation carries just so far. Wider is more expensive but the freedom to design to need is worth it, The reason that test piece design is 3"x1/2" Is that three inch collection, that I needed wood left once I found out the settings.

Btw- the reason I was able to get the zebrawood lamp I made was many low-power cuts/engraves and getting it wet after each.

Kim sells a lot on eBay and also takes direct orders via email.

His ebay, to get an idea of what he has:

His email, which he has given me permission to share:
deer56hunter@att.net

He ships quickly and his prices are very fair. The only caveat: he sands to 120 grit. The surface finish is nowhere near as refined as ocooch. Expect to do some sanding to get a nice surface if you’re making anything elegant.

One other nice thing is that he’s done custom thicknesses for me in the past. I can’t guarantee that he’ll do the same but I wanted some 0.140” maple and he milled some to my specs. A nice service.

Just to be upfront, I have no financial affiliation with him, I get no discounts or commissions. I only signal boost him because I like his products and want him to stay in business so I can keep ordering his stuff :slight_smile: I send him forum links to the projects I make with his wood, he gets a kick out of seeing what it gets turned into.

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Same. 3” is just a bit too narrow. My sweet spot is 6” but at minimum 4.

Took me forever to get through that 3” stuff because I just couldn’t find projects to use it.

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As an update to my Red Oak woes… :slight_smile:
1/4 inch red oak
125/full cut
850/full 270 Engraving

You can see the color changing w/ water (Tumeric, Zucchini, Garlic)
After cutting I brushed with soap and water with a toothbrush to remove the soot.
Customers are very happy :slight_smile:

Tested out a painted version - I learned that you can easily scrub off the paint if it gets out of line! (it’s kind of sloppy, i know)

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Home Depot Purebond plywood for Maple :+1:

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Anyone here familiar with sanded plywood from HomeDepot? I’m pretty sure it was on fire when i was cutting it and now i’m scared to continue using this…
125/full 2 passthrough and i still had to swift kick it to get it to break off…

Home depot plywood is not worth it to me, it cuts inconsistently and is prone to this sort of thing.

As far as non PG plywood goes: Baltic Birch or maybe the columbia stuff at HD. The other stuff is only when you’re desperate as far as I am concerned.

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If you want to use Home Depot, order the Purebond that @gewubs mentioned upthread. You can order it on the Home Depot website and they ship it right to your home. It is a product that Columbia Forest is manufacturing and many Glowforge users (including myself) have been very happy with. They sell it in GF size (12 x 20) times 10 pieces, and either 1/4" thick or near 1/8" (5/32).

Just go to the Home Depot website and search for PureBond and then look for the items that are 1’ x 1’7" and those are the ones specifically made for the GF.

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