DNA and light woods

[andrewleeheck]

Has anyone else had a problem with denatured alcohol (DNA) darkening the grain on light woods, like ash and maple? As I'm turning and sanding, the wood stays nice and consistently light, but as soon as I add the DNA to clean out the grooves, the grain darkens slightly while the raised portions remain light. I know an alternative to DNA is to blow compressed air onto the blanks, but I have found that it is not as effective at drawing out some of the grit. Any thoughts are appreciated.

Andrew

 

[clthayer]

I have done many ash and maple and have not had that problem. I will usually sand to 320 and then apply ca with 320 and fine sanding dust on the sandpaper to fill the grain. When the ca dries sand with 320 again to remove the ca on the surface. I do this because I find that with dark sandpapers and mm the grain on ash and maple will catch the blackness of the sandpaper.

Christian

 

[Daniel]

I would agree with Christian, except the MM part. I've never notice DNA darkening my wood, But dark colored snadpaper has many times. The problem I have had with MM is having it actually melt to the blank. That cna be cleaned off fairly easily but is an annoyance.
My first thought when I read your past is that you may be washing dirt or other dark matter into the grain when you use the DNA. Bushings can leave dark residue if you hit them while sanding.

 

[rtparso]

Just a thought DNA attracts moisture and as a result the older it is (the longer it is open) the more water it has in it. If it is raising the grain it might have a lot of water in it. Try a fresh bottle?

 

[clthayer]

I did an ash sl last week and didn't do the ca on the sandpaper. My 180-320 is yellow now and don't have any problems with that. After 320 I used mm and there was black in the grain.

I melted mm once or twice and then learned to sand at the slowest speed, going through the grits of mm doesn't seem to take long after doing the heavier sanding with 180-320.

Christian