Given something like this list, how should we decide what to Laser and what not to? https://www.wood-database.com/wood-articles/wood-allergies-and-toxicity/
I’m looking to get some more woods to try but I don’t know how much of this should factor into the choice.
I think it will come down to the individual and your ventilation setup more than anything.
In general, it’s best to wear a mask and work in well-ventilated spaces when sanding any kind of wood. if you follow those protocols and don’t have a direct allergic reaction, you’ll probably be ok.
If your laser vent setup is well sealed, (and/or you add a booster fan or GF ever decides to let us turn the fan on as we please [come on guys we want it]) you shouldn’t have much exposure to the smoke at all. If you’re really worried, you could also get a full on charcoal mask for when you are loading/unloading the GF.
I cut and work with lots of weirder woods, and have yet to have any serious reaction to anything following these protocols. The worst reaction I have is to baltic plywood smoke [it makes my throat feel weird sometimes], I suspect from the glues. I take care to stay away from the smoke as much as possible then.
I agree with @evansd2. I used the underlayment from HomeDepot for a job commision and my wife had some kind of reaction to it. We didn’t realize it until I was 90% done, but we narrowed it down to that wood. She got a headache for months until we tested the theory and stopped burning for a holiday weekend. We started up the next weekday and sure enough, her head started hurting.
We finished the job and her head stopped hurting. Just to double check the theory, we created one more item a month later. That night, her head started hurting and didn’t stop for 2 days after. During the time I after I had completed the job, I burned on PG material with no ill effects on her. I am thinking that it was the glue used or maybe it contained formaldehyde.
BUT…my wife is a very special case with MANY MANY allergies. What affects her, might not affect the next 100 people. So take that with a grain of salt.
Over the years I have had several warnings about exotic woods. Most you would never see but purpleheart is a common exotic that I was heavily warned against as an irritant. I have a big board of it too thick to cut on the Glowforge but I will be looking for someone that can make thin boards out of thick ones. Pink Ivory, Gabon Ebony, Snake wood among others are valuable enough to warrant it
Mine too, so thanks for the heads up on this.
Was there any possibility that your venting is not 100% sealed, the exhaust getting back into the house later, or is it just the effects from the residual smoke when you lift the lid, do you think ?
Honestly, I don’t know. I did use AC tape to seal the vent hose at both ends, but I would still smell the wood burning as it burnt. When it was burning, I could look at the edges of the lid and see light, so that tells me it might have been leaking, but seeing other pictures here said it was normal.
My next step was going to be getting a small rubber hose and try to create my own seal. Unit is off getting warranty work so I can’t do any pictures right now to show what I am talking about.
I had been running mine in the garage, but when I get back, SWMBO insists that I use it in the house because of the ac.
This is going to give me the additional problem of making a window vent, rather than just go through the garage wall !
I was unhappy right from the start with the coiled wire vent pipe creating a spiral gap around that very short spigot at the back of the GF, but I used a silicone rubber caulk first, then lots of aluminium tape over it all, and that seems to have done the trick.
Might be back to square one now though, but as I’m inside the house, I might go with rigid pvc pipe bends, and box it into a set of shelves.
Lists of woods as irritants have been compiled based on traditional wood working techniques - turning solid pieces of wood into tiny particles of wood. Sawdust has enormous surface area for its volume, therefore exposure to any irritant in the wood is multiplied many times in a sawdust rich environment. The laser vaporizes the wood, leaving some char and some products of combustion and no real sawdust. The kerf of a saw blade is also many times larger than the kerf of a laser beam - more wood turned into sawdust.
I’m not saying to ignore the list, I’m just saying it may not apply here. I’ve read that some people break out handling whole boards, much less sawdust, so anything is likely to vary from individual to individual. It is also very possible that woods that are not considered irritants when their sawdust is rubbed on your skin are irritants when vaporized. Temperate forest hardwoods are probably all safe - otherwise there would be folk wisdom about not burning ash in a campfire. But who knows if there is any folk wisdom around tropical woods.
And finally, it is my understanding a lot of the woods on that list are considered oily. It is also my understanding that oily woods laser poorly. So a lot of the list may be moot.
This is not necessarily exactly true, at least as far as I’ve observed it. You get a combination of vaporization and burning and a sort of explodey effect where particles get blasted from the surface by the sudden force of things getting burned/vaporized right next to them. I know that from some engraves I’ve gotten enough gummy/sooty stuff that it spoils the outline of parts downwind.
What this means for irritants I have no idea. The devil is in the details.
Pretty sure you don’t want that stuff in your lungs regardless of the species.