What is causing this, and how do I avoid it.

[Kenton Keller]

I posted about this once before specifically working with cherry, and didn't get any replies. I have run into it again, and would sure like to know how to avoid it.

This is mainly cherry and walnut, but does have a couple of paduk and yellowheart sections in the middle of it. I turned it, sanded it and then soaked it in water to raise the grain. In the picture I have already started trying to sand this out, but originally it was somewhat green like a stain copper would make. The sink I soak in is corian, with a ss drain. Last time this happened, I was never able to fully get it out, and I suspect that will be the case here also.

361183
Ideas of how to avoid or why it is happening greatly appreciated.

[Matt Day]

How long was it in the water?

When I raise the grain on flat work I spray a light coat of water, not soak it. Wonder if soaking it for too long has anything to do with it?

[Bill White]

Yep! Don't soak. Just a spritz or two will do the job.
Bill

[Mike Circo]

As mentioned, soaking is not necessary.
Is that tap water? Minerals will stain, especially if a lot of water gets in (via a long soak) then evaporates. If your tap water is mineral laden, use distilled for grain raising.

[Kenton Keller]

Thanks Guys, I guess I will try just spraying and using distilled water and see what happens. It soaked maybe 15 minutes. It doesn't do it every time, but Cherry seems to have the biggest issue. Most of these things are kitchen items, that are going to be in the water often after I put on the mineral oil- beeswax.

[Ted Reischl]

You might try using a very, very thin cut of shellac. I typically buy a can of sanding sealer which is already a thinned down version of shellac, and then dilute with an equal amount of alcohol.

Shellac is food safe, in fact they use it to coat a lot of different pills.

Light sanding after it is dry, usually about 15 minutes or so at most. Very light sanding, the idea is to NOT raise the grain again.

[Don Jarvie]

All you need is to wipe it with a damp rag and the grain will raise. I do this to see if I got all of the sanding marks out.

[Bill Dufour]

Looks like mold to me. What was the temperature and humidity in the shop when this was wet?
Bill

[Kenton Keller]

After I took it out of the water I set it outside to dry I think it was around 80 degrees or better with not much humidity

[Bohdan Drozdowskyj]

Could it be an iron reaction to the tannins in the timber. When you set it to dry what was it resting on?

[Paul K. Johnson]

I'm thinking it is either mold or a chemical reaction with something in the wood with something in the sink (bleach, detergent, who knows...).

[Ed Aumiller]

Is it water with chlorine in it ?
i.e. city or town water ??

[Wayne Lomman]

It's a specific mould/fungus that occurs in some species (can't remember the name). Sawmillers have to be aware of it as it can occur in green logs if not milled and dried correctly. Keep the timber dry or if you must use water to raise the grain, wipe with a damp cloth and no more. Distilled water is way overkill. Any potable water is fine. Cheers

[Prashun Patel]

I think it is too uniform to be mold. I suspect iron or minerals in your water. Is the staining more with certain species such as white oak? Does the staining turn a brown color after months?

Does this happen if you soak it in distilled water or denatured alcohol instead of tap water?

[Bill Orbine]

Did you use steel wool on the wood for sanding. Or used a sandpaper that had been used for sanding metal before sanding wood?

[Wayne Lomman]

Sorry to disagree but it has the appearance of routine fungus spread by pine beetles. Have you seen timber sold as 'blue(insert species)'? It is this fungus. It is how they get rid of otherwise downgraded timber. Cheers

[John K Jordan]

All you need is to wipe it with a damp rag and the grain will raise. I do this to see if I got all of the sanding marks out.

That's what I do to raise the grain. I sometimes mix the water with denatured alcohol which seems to dry a little quicker.

BTW, to highlight the sanding marks (and see what the color and figure will look like I use wipe on naptha. It works very well and dries so quick.

JKJ

[Kenton Keller]

Thanks again for all the replies and suggestions. See if I can answer a few of the questions.
The only tools that touched it were carbide, and clean fresh sandpaper.
While I don't scrub the sink out , I always spray it out, and make sure there is nothing obvious stuck on the surface.
I used to brew beer here and did some research into the water. There is no chlorine, can't remember for sure about the mineral content.
After the soak I set it on a cement table outside.
I have never tried anything but water to soak them in, and it only happens once it a while.
I had only seen it on Cherry previously. The main wood with the stain in the picture is cherry, so I wonder if it bleed to the wood next to it?

If it is fungus or mold, is that going to be an issue if this is used for food contact? I threw some spoons I had made away because of this, but I have way to much time in glue ups on this to give up on it so easily. I do soak them in mineral oil, let that soak in for a day or two, and then heat up a combination of mineral oil and beeswax and apply that to them.

[Frankie Hunt]

Why is it on 2 different woods? Why is it not all the way around? Was that side touching something for a little while, perhaps while sitting in the sink or while drying or?? If so perhaps it is a reaction with whatever it was touching.

[Bob Bouis]

Sap stain pretty much only happens in sapwood and it usually or always only happens to unseasoned wood.

It definitely looks like the tanin stains from contact with metal and moisture. You see this all the time when cutting green oak. The sawdust turns blue and gets into the pores of the wood.

[Reed Gray]

I get metal stains like that all the time on my wet wood. It comes from metal dust on my hands and on my tools when sharpening. Try some concentrated lemon juice on it. If still fresh, usually gone in a few seconds. If it has dried out some, it can take a couple of applications. If the wood is dry, it can bleach out some of the color as well. I do make sure to wipe my hands and the tools after I sharpen, but it doesn't always work....

robo hippy

[robert baccus]

Why the grain raising to start with--seems to cause delays and problems. I've been turning 25 years and flatwork before that without water. Shoot it with lacquer SS or shellac and power sand or handsand with 180 grit and go about your finishing. That's one reason they call it Sanding Sealer.

[ron david]

if it is iron stain I would try a little oxalic acid and that should remove the discolouration. you buy it in crystal form and it dissolves in water. after the colour has gone give it a wioe with vinegar and after that clear water. vinegar neutralizes the oxalic acid.
ron

[Prashun Patel]

How does vinegar neutralize another acid?

[Reed Gray]

Hmm, vinegar is acidic.The floors in places that make vinegar are wood because vinegar eats concrete. If you have the concentrated lemon juice, or some lemons, try that.

robo hippy

[David Metzman]

Why the wetting? Do many people wet to raise the grain before sanding? Do you do this to things that would be used in a kitchen like a salad bowl?

[ron david]

How does vinegar neutralize another acid?
it works. don't know why but it does. been doin it for years and that info was passed on to me. I have also been selling oxalic acid for years
also have an aquaintance that use to buy oxalic acid the 25 lb bag to clean log houses and used vinegar when required
ron

[Bill Boehme]

Spritz the wood very lightly with DNA and then light it to burn off the alcohol. be careful, the flame is almost invisible. Also, don't wet the wood so that it shines. Just a gentle spritz that barely changes the color of the wood without looking wet. You can skip the igniting part and wait ten minutes for the alcohol to evaporate.