Question: How long does a 3 inch slap take to dry?

[chadwilli51]

I just milled up four 3" slaps out of a pine. The wood is still very wet. I live in colorado where it is dry. I sealed the ends up after I cut the slabs. How long should I wait before I do anything with the wood? I want to make a coffee table and a bench. Any ideas? tips? should I keep the wood in a cooler shaded barn? should I tarp it? any ways to keep the wood from cracking?
-Chad

 

[MHouse1028]

rule of thumb 1 inch a year air drying

 

[chadwilli51]

Should it be shaded?

 

[bobt]

I agree that one inch per year is pretty good.

The boards or slabs or planks should be out in the open, not shaded, so they can get all the air movement possible along with the heat of the sun. The piles should be weighted to help stave off warping. Further, the piles should be covered with some covering only on the top of your choice to prevent being soaked with rain. We always used something like corregated metal. The cover is only on the top, so the sun and heat and air movement are never compromized. Of course the boards or thick planks MUST be seperated by "stickers" (think 1 by 1 dry boards about 2 feet apart in every layer in the the piles). Do not use green unseasoned stickers as wherever they contact the boards or planks they will discolor the boards. If you do not "sticker pile", you will have nothing but moldy lumber, as the boards need to be seperated to dry.

Bob

 

[john taliaferro]

3'' thick and a 1/2'' wide not long . Yes i wait a while then bring it in and finish drying in shop but mine is only a 1" thick

 

[Cody Colston]

I just milled up four 3" slaps out of a pine. The wood is still very wet. I live in colorado where it is dry. I sealed the ends up after I cut the slabs. How long should I wait before I do anything with the wood? I want to make a coffee table and a bench. Any ideas? tips? should I keep the wood in a cooler shaded barn? should I tarp it? any ways to keep the wood from cracking?
-Chad

As BobT wrote, the slabs need to be sticker-stacked, weighted and covered to keep off rain. An open-sided shed is best but corrugated sheet metal that overhangs both the ends and sides will also work. Shade cloth, available from nursery suppliers and hung around the sides will keep rain from blowing in while still allowing air movement through the stack. You will need plenty of air flow to prevent the Pine from mildewing.

As for how dry it needs to be before working it, a cheap hygrometer from a home center placed in your home will answer that question. Once you know the average RH inside, you can know the corresponding EMC (equilibrium moisture content) that the wood will reach. Ideally, the wood needs to be dried pretty close to that value prior to working it. At a guess, I'd say somewhere around 6% MC in Colorado. If only air drying, you can count on at least four years. You should consider having it kiln dried. Since it's a softwood, it can be dried rapidly without risk of degrade, saving you years of waiting.

You can use the calculator or the table in the attached link to determine EMC for a given RH. Wood Equilibrium Moisture Content Table And Calculator

 

[BlueRider]

The 1 year per inch of thickness is a good guesstimate but it really depends on the type of wood, average humidity, and temps where you live. Colorado is rety low humidity so it will dry a bit faster than if you lived someplace like Georgia.

The purpose of covering the wood is not so much to keep the rain off the wood but more importantly to keep direct sun off the stack. Rain will cause very little degrade and contrary to what one might think it really does not re-hydrate the wood to any significant degree. direct sun on the othe hand will cause one side to loose water at a greatly accelerated rate compared to the side not in direct sun and that will cause severe warping and increased cracking.

 

[discounthunter]

depends, how hard did you get slapped? sorry coundnt resist.

 

[Cody Colston]

One other point. Pine also needs to be kiln dried to set the pitch. If you don't kiln dry, consider a base coat of shellac when finishing. That will seal in the pitch and help keep it from ruining the finish.

 

[qweesdraw]

I find wood dry's a bit faster in our dry climate.
(Lodgepole seems to dry faster than Ponderosa)
Check it @ 16 months with a moisture meter.
Mark

 

[chadwilli51]

Alright, this helps a lot. Does anyone know anyone who Kilns dries wood in colorado? Also, do you think the wood will crack or check if it is not properly dried? Im going to leave the slabs in whole pieces to make my projects, so if I seal the wood with a varnish or something of the type, will be alright? Also, how do I determine the EMC of the wood? Thanks for the help.

 

[qweesdraw]

Alright, this helps a lot. Does anyone know anyone who Kilns dries wood in colorado? Also, do you think the wood will crack or check if it is not properly dried? Im going to leave the slabs in whole pieces to make my projects, so if I seal the wood with a varnish or something of the type, will be alright? Also, how do I determine the EMC of the wood? Thanks for the help.

I have a small kiln 8'x8' no frills solar i use it to dry bundle wood if i run low.
It's @ 126F as i type @ 2pm with 4 small fans running.
Your welcome to use it's basically empty @ this time.( it will cost you a case of beer)
Lyons Co.
Mark

 

[Jeff_M]

I just milled up four 3" slaps out of a pine. The wood is still very wet. I live in colorado where it is dry. I sealed the ends up after I cut the slabs. How long should I wait before I do anything with the wood? I want to make a coffee table and a bench. Any ideas? tips? should I keep the wood in a cooler shaded barn? should I tarp it? any ways to keep the wood from cracking?
-Chad

I live in south central Washington State where we get a fair amount of wind and only about 7" of moisture a year. I milled some 3" thick Oregon Ash cants (by 6" to 16" wide) 13 months ago, stacked outside with some plastic on top, and recently moved it in my workshop to surface about 2 months ago. I heat with wood in the shop so the last two months the shop was at an average relative humidity of about 48%. I measured moisture contents of the outside of 6-8% and inside of the slabs of around 13% while I was resawing and surfacing.

The other benefit of kiln drying would be killing any beetle activity in the wood, especially if you left bark on your slabs. I'm trying some Tim-bor on 3" hybrid poplar I am drying outside now, if that doesn't work, I probably will construct a inexpensive kiln to at least get the wood above 160 degrees F, for long enough to kill all the insects.

I usually alternate using paint and polyurethane on the air-dried wood to help slow down the more rapid drying of the ends, with more layers for higher value wood.

 

[Cody Colston]

You only need to seal the endgrain on the wood to slow down the moisture loss and promote more even drying. I use Anchorseal but paraffin wax, roofing tar or aluminum paint mixed with varnish are also good sealers.

A clarification on setting the pitch. The pitch will basically be "set" at whatever is the maximum temperature the wood reaches when drying. If the wood again reaches or exceeds that temperature, the pitch will become fluid again. So, the higher the temperature when drying, the better.

To sterilize the wood (kill any insect infestation) it is necessary to heat the wood to 133 degrees at the core. Most solar kilns don't hold the temperature high enough for long enough to heat the wood all the way to it's core. I think mine did last summer but that's because it was around 110 degrees ambient during the afternoons. The 140 degree thermometer I had in there stayed pegged out most of the day.

Timbor is a good product to prevent insect infestation if they are not already inside the wood. It's simply a borate and is non-toxic. I use it for treating my air-drying lumber. But, since it's a topical treatment, any critters already present in the wood will not be affected.

 

[SDB777]

Since it's pine...I'm thinking a kiln would be better. Anyone around ya that would let you share some room in theirs for awhile?

No color loss from the kiln since it's pine anyway, why not accelerate the process?







Scott (just a thought) B

 

[chadwilli51]

How long would it take for a 3" slab of pine to dry in a kiln? Also, when I make my projects, if I want to leave the bark on, how would I go about doing this? Do I just coat it with something thick like an exterior varnish?

 

[BobL]

How long would it take for a 3" slab of pine to dry in a kiln?

That depends how much of a chance you are willing to take for it to come out checked.
My guess is a 2-3 weeks.

Also, when I make my projects, if I want to leave the bark on, how would I go about doing this? Do I just coat it with something thick like an exterior varnish?

In general the bark comes off no matter what you do to it. If you really do want the bark (personally I reckon its dusty awful stuff) then let it come off and glue it back on again when everything is dry.

 

[Cody Colston]

How long would it take for a 3" slab of pine to dry in a kiln? Also, when I make my projects, if I want to leave the bark on, how would I go about doing this? Do I just coat it with something thick like an exterior varnish?

I'm not really sure how long to dry 3" thick pine but I believe nominal 2" construction lumber is dried to 19% in about a week. Thicker lumber will naturally take longer as will going to a lower MC. Two weeks is probably a good estimate. Softwoods are much less dense than hardwoods and, as SDB777 noted, actually benefit from rapid drying as it prevents staining. Cracking is not normally an issue.

I've never tried leaving the bark on a slab but for natural-edge turnings, I use cyanoacrylate glue (superglue) to help keep the bark intact. I try to saturate it with thin CA where it meets the cambium layer, then saturate all the bark. It would take quite a bit for a slab like yours. You would want to do it with good ventilation, wear safety glasses and rubber gloves. It will stick your fingers together instantly and the fumes from curing CA can be irritating.

 

[twoclones]

The 1 year per inch of thickness is a good guesstimate but it really depends on the type of wood, average humidity, and temps where you live. Colorado is rety low humidity so it will dry a bit faster than if you lived someplace like Georgia.

My 2" X 20" x 60" Sycamore slabs (sawn from green logs) test at 12% after 2 months. However, I live in the desert where 6" of rain is a very wet year, normal summer temps reach 110 F and higher, and I'm not sure what that "Humidity" stuff is that BlueRider is talking about.