Moisture level fluctuation during transportation

-- 0 --

My shop is located in a hot, humid town. I rent a paint booth that is located in a different address in the same hot, humid town.

I will be using my pick-up truck to transport some kiln-dried 8% MC solid wood boards between the shop and the paint booth. I plan to make an indoor sign out of the boards for my friend in Washington state, which has dryer, cooler climate.

Questions:
How do I make sure my wood’s moisture level won’t increase dramatically while being transported between my shop and the paint booth?

I plan to finish the boards with 4 layers of 2K Polyurethane. Do I have to spray the boards as soon as they arrive at the paint booth since the boards just got in contact with moist outside air?

How soon will the wood increase moisture level from 8%? Is there a formula to calculate this?

Bill

It should not change moisture appreciably. If you are concerned let it acclimate for a few days before you finish it.

David R Sochar

Member

Air dried lumber, when stacked and vented properly, takes about a year to go from the sawmill to about 10%MC. A year per inch of thickness is the rough rule of thumb.

I think that unless that is a very slow trip across town - about a year - you will not see any change in MC in your boards. 8% is probably close to the EMC for your area, so your sign will want to stay at 8% if the environment allows it.

It is always a good plan to allow things to acclimate when possible.

rich c.

You must air condition the hell out of your shop if you are worried about the trip across town. If the wood is cold from the A/C, it might get a little condensation when sitting still, but traveling at 40mph in the pickup will limit that. Make sure 4 coats does not exceed the manufacturers thickness restrictions.

Jenny

Member

Hi David, Bill, Rich and everybody here,

Thank you for your input.

I don’t know if I am overthinking this, but I am wondering if I should plug the end grain with epoxy or Titebond.

Should I apply Epoxy or wood glue on the end grain before finishing the sign with 2K Polyurethane?

Since the end grain tends to suck up more moisture comparing to other parts of the board, would plugging the end grain with marine epoxy/Titebond before finishing make the moisture fluctuation more even across the sign?

If so, should I apply the epoxy/Titebond BEFORE or AFTER transportation the sign to the paint booth?

Lastly, would packaging the sign in a vacuum-sealed bag a good idea? I will be mailing the indoor sign to my friend in Washington state from Houston via UPS Ground.

I am trying to make sure my sign (essentially a glued-up panel) does not warp/cup/twist in the future.

David R Sochar

Member

I am not sure about the word “plug”. Semantics. But it is a good idea to seal up end grain, you just may be adding an unnecessary step. First coats can be sanded, helping to get build on that end grain.

The other consideration is will the finish stick to it? I can't picture anything much sticking to TB. Sanded epoxy will accept more epoxy, and probably other coatings.

Paint - don't plug - with thinned epoxy (half epoxy, half acetone). Let it cure 48 hrs, then sand and begin the finish.

Around here, “plug” refers to chewing tobacco. Fresh, or used. I don't think it would help your sign.

rich c.

You've actually "plugged" end grain with glue before finishing? It will look like hell since the finish will be sitting on top of a film, and likely won't stick at all. Have you not worked with solid wood before? Maybe you could just hire a refrigerated truck to haul the wood over to the booth! LOL

Jenny

Member

Hi Rich,

I am a young British girl living in the US. I am trying to impress a boy who lives in Washington state. I am just trying to do everything I can to make sure things go perfectly.

I am sure when you were younger trying to impress girls you liked, you overthinked things and got nervous. I hope that since you have way more experience in life and woodworking, you would understand.

rich c.

Woodworking was never part of my mating ritual, young or old! LOL

Jenny

Member

I am extremely bad at sewing so I am doing some woodworking. Lol

He hates MDF so I am trying my best to make a painted sign with glued-up panel.

Tom Gardiner

While transporting your unfinished sign, make sure you don't have one side exposed to the sun such as lying flat in the back of a pickup or hatchback. The sun and wind will dry one side which will cup the sign. Cover it with a piece of cardboard at least, ply would be better.
The key to avoiding distortion is to have both faces treated the same way. Same amount of finish, same packing materials, same air flow.
I'm sure the sign is a better choice for courting. Two former girlfriends began knitting me sweaters that was the kiss of death of the relationships.

GeneWengert-WoodDoc

If you want to be super safe, just wrap the material with a couple of layers of lasting wrap (Saran). You can get large rolls from big box stores.

0 --

To receive email notification of additions to this forum thread, enter your name and email address, and then click the "Keep Me Posted" button below. Please Note: If you have posted a message or response, do not submit this request ... you are already signed up to receive notification!
Your Name:
E-Mail Address:
Enter the correct numbers into the field below:
Date of your Birth:	Return to top of page