remove mold on greenwood roughed bowl

  • Advertise with us

« back to Woodturning forum

Forum topic by banjobarry posted 07-14-2016 04:05 PM 6561 views 0 times favorited 8 replies Add to Favorites Watch
View banjobarry's profile


7 posts in 3786 days

07-14-2016 04:05 PM

Topic tags/keywords: woodturning greenwood mold

Hi all,

I’m pretty new to greenwood turning. This spring I rough turned some bowls in my workshop from a recently cut cherry tree and they’re drying out just fine. I put a coat of anchor seal on and stuck them in a corner. My workshop is in New York City. But this past week I turned some more bowls (I think the wood is cherry but I’m not sure), and they’re growing lots of mold.

Is there a safe way to get rid of the mold? Or should I just throw the rough turnings out?


8 replies so far

View soob's profile


271 posts in 2328 days

#1 posted 07-14-2016 04:49 PM

When you re-turn it, all the mold will be cut off. It’s only skin deep.

I don’t think it’s typically hazardous to your health (at least, I hope not!) but if you want it dead, you can spray it with dilute bleach.

View Wildwood's profile


2959 posts in 3254 days

#2 posted 07-15-2016 10:34 AM

Mold, sapwood stains, and decay caused by fungi. Micro-organism in the air or ground produce the fungi. Sapwood stains defer because thought to be caused by insects & birds eating the wood and birds damaging the wood to get to insects. Stains also look like mold so often included in bio-deterioration of wood.

Wood offers the required food supply for mold growth; and need moisture, mild temperatures and air (oxygen) to grow. Fungi that causes mold may already present in wood but not visible, given the right environment of moisture, mild temperatures, and oxygen starts to grow. Mold growth occurs in wood with moisture content of over 20% below that MC .

I never seal a roughed out bowl blank or store them in plastic due to where I live! If use shavings & paper bag, or bag by itself to store roughs take them out after a week or two to air dry.

You may or may not be able to remove stains caused by mold or blue/black stains caused by bugs & birds. If going to turn away mold make sure wear better protection than a dust mask and do wear glove when handling/turning May need a scrub brush & bleach solution to remove mold, not so sure about stains.

-- Bill

View bigJohninvegas's profile


1044 posts in 2581 days

#3 posted 07-15-2016 04:06 PM

Mix up some bleach water in a bowl or I use a small spray bottle. About 25% bleach.
Wipe it down and all the mold should disappear.
Stand clear and let it dry for a moment, don’t want to sling bleach on your clothes.
I wear a resperator when I turn moldy or spalted wood. Keeps my allergies under control.
If the mold has been on it long enough to permanently stain it, finish it anyway. My be a cool detail in the wood.

-- John

View banjobarry's profile


7 posts in 3786 days

#4 posted 07-17-2016 12:16 PM

Thanks for all the tips! Appreciate your taking the time.

I sprayed the bowls down with a mold remover, then re-turned them lightly to remove the surface mold. I think they may have been too wet, and it was too humid. I let them dry out a bit without the seal, then resealed with a lighter coat. And now I have a fan blowing on them. Seems like that’s working pretty well.

View soob's profile


271 posts in 2328 days

#5 posted 07-18-2016 07:25 PM

A bit overboard. The mold would have stopped growing once the bowl stopped losing so much water. It could have been turned off later with no harm to the wood.

Also the fan increases the risk of cracking significantly unless the humidity is very high. You want to slow down the drying as much as you can.

View banjobarry's profile


7 posts in 3786 days

#6 posted 07-18-2016 09:35 PM

Yeah, I just feel better about them without the mold. I’m sure as I do more of these I’ll care less.

The humidity is high, for sure. It’s sticky, and if you’ve been in New York city in July you know when I say sticky I’m right. I turned some greenwood back in the winter and spring and everything went just fine, but not now. But yeah, soon I’ll take the fan off.

Thanks again everybody for the feedback.

View javillaxy's profile


3 posts in 319 days

#7 posted 05-14-2021 04:42 PM

From what I found online, dip a soft rag in vinegar and wipe the mold off. You can also spray with diluted bleach. Most times, humidity is a major catalyst for mold growth on finished and unfinished wood. I dug out the options here:

View darthford's profile


739 posts in 3043 days

#8 posted 05-14-2021 06:33 PM

Here in the Pacific NW rain forest home of constant assault from mold, moss and algae we use a product called Wet and Forget. Gentle acting and takes a couple of weeks but keeps the mold, moss and algae away for up to 1 year. You can use it on multiple surfaces, wood decking being one. Check out some of the before and after pics for this product.

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics