iDRY Vacuum Kilns

Sponsors:

Relative humidity and mould

Started by JoshNZ, July 21, 2022, 03:43:41 AM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

Print
Go Down Pages1
User actions

JoshNZ

July 21, 2022, 03:43:41 AM
I've put a fairly wet load of timber (Blackwood) in the kiln and am just wondering if there is a safe relative humidity to stay below, where mould will not grow anywhere inside?

I  had fans on it for 10 days after sawing then straight into the kiln (we are in a rush for this one). They're only 17mm boards so hoped it would move quicker than it is. The humidity sensor has been stuck over 96% since it went in 4 days ago, but pouring water out the drain. I opened it up today expecting the worst - hit in the face with a plume of steam. I've got a few little cultures growing around the ends of the stack, not sure what the centre would look like.

How far does the RH need to come down before I can relax about it?

K-Guy

#1
July 21, 2022, 08:52:55 AM

That dries similar to our soft maple, so my guess is that you are overloaded and should pull a couple hundred board feet out as the mold is probably ready to explode in growth.
Nyle Service Dept.
A common mistake people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools.
- D. Adams

YellowHammer

#2
July 21, 2022, 10:35:26 PM
If you want to prevent mold, it's a good idea to have a 10% DB/WB depression, so adjust your kiln settings and then your load size.  
YellowHammerisms:

Take steps to save steps.

If it won't roll, its not a log; it's still a tree.  Sawmills cut logs, not trees.

Kiln drying wood: When the cookies are burned, they're burned, and you can't fix them.

Sawing is fun for the first couple million boards.

Be smarter than the sawdust

JoshNZ

#3
July 22, 2022, 04:19:41 PM
It will have to stay as it is this round, I haven't got time to tweak this load. Will treat it as an experiment and see if Acacia stains with that kind of mold growth. I imagine at some point the DH will start winning the battle and the mold won't last much longer past that?

It is the smallest charge I have ever had in there, but very thin boards and green, I guess with the extra surface area it is flatout giving up moisture. I baffled about a third of the chamber with plastic too so the airflow through the boards is noticeably higher than normal.

Just for interests sake is there anything else that can be done for the mould? Fungicide? Sterilisation temps won't kill bacterial i take it?



 

JoshNZ

#4
July 22, 2022, 05:15:17 PM
What about leaving the heater on for the first week and venting? I know it's not the cheapest way to do it but for a guy in my position without the time to tend to it?

From memory the first step in kiln schedule for green Acacia was 85% RH so I assume as long as I don't go below this there's no prob with it?
Print
Go Up Pages1
User actions

Thank You Sponsors!