Black Mold vs Sweetgum?

[Rick Helmig]

Greetings All,
Is this bad? Normal?
Last week I roughed out a large batch of green Sweetgum, coated them with Anchorseal 2, and stacked them up to dry. This is my normal process here in Georgia and so far has worked well for me. However, I have never turned Sweetgum before. And within just 3 days every piece turned black with mold.
I'm not sure what to do here...
- Is this a known result with sweetgum?
- Any recommendations on how to deal with these? Spray them with something perhaps? (I'd like to ensure they stay food safe)
- Might this mold negatively affect the final bowl color?

 

[Tom Hansen]

I've turned a bit of sweetgum and not had that problem. Heat will kill the mold spores so potentially clean it up and microwave nuke it.

 

[Richard Coers]

Normal? for wood it can be. Fairly certain it's not species related. Yes, it will definitely affect the wood color unless you have enough wall thickness to turn it away. Personally, I'm not a fan of working actively moldy wood. I guess I'd start easy and try lemon juice to kill it. Household bleach would be my second choice. And since I'm no fan of black mold, I would not turn or sand it unless you are successful in removing it with the juice or bleach.

 

[Karl Loeblein]

Greetings All,
Is this bad? Normal?
Last week I roughed out a large batch of green Sweetgum, coated them with Anchorseal 2, and stacked them up to dry. This is my normal process here in Georgia and so far has worked well for me. However, I have never turned Sweetgum before. And within just 3 days every piece turned black with mold.
I'm not sure what to do here...
- Is this a known result with sweetgum?
- Any recommendations on how to deal with these? Spray them with something perhaps? (I'd like to ensure they stay food safe)
- Might this mold negatively affect the final bowl color?
View attachment 36105

For these, I would scrub down with some bleach water, and then turn away the outer surface. Coat surface with lemon juice before letting it dry a second time. I normally don’t coat sweet gum with Anchor Seal.

For Next ones, try sticking some rough turnings in a freezer to let it freeze dry some, or try boiling a blank for an hour which can cut the drying time in half.

 

[Bernie Hrytzak]

I have recently tried washing/wiping with white vinegar, might have to do it twice a few days apart, worked for me on box elder that was starting to mold. After 2 washings there was no discoloration.

 

[Rick Helmig]

Thanks all. I'll get them sprayed down tonight and will likely remove the anchorseal from them this weekend. What's odd is I had turned equally fresh poplar and maple that same day, used the same process, and no issues on them.

 

[Mark Jundanian]

I wonder if any application of cleaner will be that effective while the Anchorseal is still on the piece? I assume the mold is under the wax layer.

Reading through the posts above I wonder if boiling might both remove the Anchorseal and kill the mold?

 

[hockenbery]

Thanks all. I'll get them sprayed down tonight and will likely remove the anchorseal from them this weekend. What's odd is I had turned equally fresh poplar and maple that same day, used the same process, and no issues on them.

Kill the mold with Clorox as soon as you can.

to get mold growing you need to have some spores.... we all know this.
What we don’t know is which bowls have mold spores lurking about.

moisture content + mold spores + conducive environment. -> mold.

you seem to have a bumper crop. I have never seen mold improve the color or look of a woodturning.
I dry the few bowls I do in bags. I rebag in dry bags every day until the bags are dry (about a week)
Any sign of mold I wipe the bowl,with Clorox and discard the bags.

hollow forms and NE bowls I rinse in the sink mostly to hydrate the endgrain a bit but it likley reduces the mold spores.
They dry in a few days and mold is very rare on those.

 

[robo hippy]

At first glance, I thought that was a very big metal stain. I don't use the anchor seal, but do use stretch film when I want a bowl to keep for a few days. I always get mold under the plastic when I use it on maple. I had guessed it was related to the high sugar content in maple trees, and those little nasties that like to turn good wood into compost love sugar. I don't think I have ever turned any sweet gum, though had a tree of it in my yard years ago that I wanted to cut down because you can't walk bare foot in a yard that has those trees in it.... Some of that may turn off, but it appears to be mostly on the end grain, and things penetrate deeper into the end grain than they do in the side grain. No way to tell until you finish turn them.

robo hippy

 

[Leo Van Der Loo]

Mold needs moisture higher than 30% to live, lower that and the mold dies.

Using anchor seal can have the mold grow under it, and of course as it does not, or very slowly dry, the moisture stays high.

I never use anchor seal on my turned bowls, I always use brown paper bags with nothing else in it, check the first week or so a couple of times, to see if there is any mold/fungus growth.

If there is any mold, I wipe it off with a dry rag, and stick the bowl in a dry brown paper bag, I let the used bag dry and will use it again when dry, as the mold is dead in/on the bag.

I have been doing this for the last twenty years and longer, and it works, mold spores are everywhere and they will grow if the condition is right,

it will not grow on dry wood or stay alive on dry wood, just dry your wood and you don't need to use anything to kill it, oh and there are spores flying around as we speek, so just change the condition of the wood and you are safe.

 

[Ric Williams]

I received a maple bowl blank a couple weeks ago that's sealed in wax and when I checked it last night, I found black mold growing on it. Can't tell if it's under the wax or on top of it, but i suspect it's under it. I'm planning to clean it off and turn the wax off and let it set without it. I have a big Hickory blank that's also sealed in wax. It was sitting next to the maple blank and it got a little mold on it too. I hate having blanks entirely wax coated. I wouldn't think that mold would grow on wax, but then gain, I don't know that it wouldn't.

 

[Karl Loeblein]

I received a maple bowl blank a couple weeks ago that's sealed in wax and when I checked it last night, I found black mold growing on it. Can't tell if it's under the wax or on top of it, but i suspect it's under it. I'm planning to clean it off and turn the wax off and let it set without it. I have a big Hickory blank that's also sealed in wax. It was sitting next to the maple blank and it got a little mold on it too. I hate having blanks entirely wax coated. I wouldn't think that mold would grow on wax, but then gain, I don't know that it wouldn't.

Coatings like wax or Anchor Seal help keep green wood blocks from developing cracks so think twice before removing it. Anchor seal allows the wood to breathe a little more than wax so many turners prefer using that product. You might try removing some of the heavy wax by using a heat gun and a paint scraper. Better yet, don’t let your green wood blocks with a lot of moisture content just sit around. Get them roughed turned ASAP unless you want to deal with mold, spalting or cracking. Though I’m a big fan of spalted maple.

 

[Leo Van Der Loo]

I received a maple bowl blank a couple weeks ago that's sealed in wax and when I checked it last night, I found black mold growing on it. Can't tell if it's under the wax or on top of it, but i suspect it's under it. I'm planning to clean it off and turn the wax off and let it set without it. I have a big Hickory blank that's also sealed in wax. It was sitting next to the maple blank and it got a little mold on it too. I hate having blanks entirely wax coated. I wouldn't think that mold would grow on wax, but then gain, I don't know that it wouldn't.

Not a good idea Nic, rough turn the blanks and then place it in a brown paper bag is the way to go.

Right now you could scrape the wax off and the mold, then replace the wax with anchor seal, only good for a short time as the mold will very likely come back.

I guess Karl has basically the same idea

 

[Bill Boehme]

How you dry wood depends a lot on the climate in your part of the world. It's mostly hot and dry in north Texas so mold is not usually an issue here and Anchorseal works great for me.