Is 91% pure isopropyl alcohol OK for cleaning char off of wood, or will that 9% of other stuff (presumably water) cause swelling?
Vinegar is a great option, albeit smelly for a few moments.
@PrintToLaser has used iso to clean though I can’t seem to find the post where he talked about it, so I don’t know the %. Maybe he will chime in.
Vinegar is 95% water so you should expect some warpage. 91% IPA obviously has 9% water so it’s also a risk although less so. Personally I prefer denatured alcohol (ethanol), which should be pretty dry.
If you are soaking an item in it then yes, but that’s not to intent. To much of any liquid will cause warping. A light wipe with a rag dipped in vinegar will remove char.
I frequently use short soak (under 2 minutes) in 91%, or a splash, and a toothbrush with wood. I’ve not noticed any serious impact from that. I’ve not tried that with any pieces that are supposed to precisely fit. With 91%, it dries pretty quickly. I’ve specially done this with wooden tokens or any time I’m needing to clean burnt sap or resin off something.
I have used both without any noticeable difference, except maybe how quickly the smoke residue softens. Soaking 15 - 20 tokens for about 2 minutes softens the stain where in rubs off easily, by the time I get to the last one it has been soaking for about 10 minutes, and the stain is just laying on the surface and instantly wipes off. Beats weeding by miles. I prefer to buy the higher concentrations. Acetone works too, but alcohol is kinder to my olfactory orify. I haven’t tried denatured or vinegar.
Will it remove the char from the cut ends as well? Or are those…toast?
Results will vary but that’s what I use.
I haven’t tried it on wood, but I’ve taken to shaking up chipboard cuts (which is basically just paper - so it chars pretty good) in a bag of baking soda.
Salt would probably work pretty well also but I haven’t experimented with it yet. With photo paper on the front of these, it might scratch those. For other materials or situations, that may not pose a problem.
Well I’ll be. Excellent tip!
Great tips, all. This forum is the best.
Have you considered trying something like Gojo cream hand cleaner (note: not their pumice loaded cleaner!)? I’ve not tried it, but been mentioned numerous times on woodworker forums as a feasible solution.
I’d be worried about alcohol being excessively harsh on some of the natural woods.
I did some 3D engraving on Basswood tonight and can say with some firsthand experience that it will warp with an alcohol cleaning. I did get it pretty soaked trying to clean it up though. When I saw it happening, I soaked it for about 15 seconds to encourage the bend.
Which alcohol: 91% isopropanol or denatured alcohol?
It was Isopropanol
There are two strengths of isopropyl at most stores, 91% and I think the other is in the 70% range. Which does it say on your bottle?
And acetone can be kind of tough on your skin, unless you get the fingernail polish remover kind. Not sure what all is in that, but it is supposedly gentler on the skin than pure acetone. Good to know about a quick soaking.
Wow! In the picture, the engraved side is toward the bottom?
Did the warp lessen as it dried?
Most of the cleaning I have done is on ply.