Seal and deal? Epoxy Question

[kombatfish]

Howdy,

I live in Alaska and have a little chain saw mill action going on. I cut some would last year, but I did not paint or treat the ends. I have some fresh stuff that I have been cutting into 4" slabs about 18" wide. Now left alone they will shrink. I have one particular slab that I have been working on at 20% moister, tested end grain inch deep. What if I just epoxy resin the whole damb thing.... literally the whole thing? Wont that just trap all moister? will it rot? will it be fine inside versus outside? O yeah- paper birch

Edited April 26, 2016 by kombatfish
add stuff

[Coop]

On the advise from a friend that owns a mill, I applied latex paint to the ends of some walnut and pecan about 18 months ago and stickered them. So far very little if any checks/splits.

[Tom King]

I don't think coating the whole thing with epoxy will do anything you would want it to do.

[Eric.]

Yeah I agree with Tom 100%.  I don't know what moister is but I bet you don't wanna trap it in epoxy.  Try a kiln maybe?

[wdwerker]

I'm with Coop, wax or paint the ends. Keep the weather off of it somehow.

[Coop]

Can't imagine how much $$ in would cost to epoxy 4"x18" slabs only to end up with time capsules. Nope, probably not the right route to take.

[RichardA]

You want the moisture to escape through the long grain, not the ends, just seal the ends with a good paint, cover it and allow it to do what it's gonna do!

[toddclippinger]

I have sealed end grain with Anchor Seal, latex paint, and pre-cat lacquer (I always have the pressure pot loaded and ready to go at any time so it was convenient) then I kept the stock protected from the weather. 

All methods so far have performed equally well. 

[Tpt life]

I did a paste wax test that also performed well indoors. Likely that is a last resort option. 

[kombatfish]

Ok I guess the long route and painted ends. I will do this on some of my logs but I like some of the checking and saw marks. I like to celebrate the crack and fill in with black dyed resin to make it pop.

I don't know about the kiln idea because birch will darken when kiln dried. If I build a tent and use a forced air ready heater, is there somewhere I can view time to dry and therefore calculate cost?

I have heard of waxing the ends of logs but I am unfamiliar with the paste wax test. Could not pull up anything on line. I think I will paint the ends on some logs for nice boards and just bring some 6' logs in the garage and let them check. Test moisture till they are about 15%. Don't buy a crappy cheap probe tester. I get readings all over the board and can't detect moister on kitchen chairs that absolutely should have some moisture.

[Coop]

You refer to logs. You are planning on milling these into slabs and not trying to dry a log, right?

[kombatfish]

Trying to determine if it is better to cut the slabs while the log is fresh or let the logs season and mill later. I will be sealing some logs to use later in the log form, not milling. If I am lucky some of the Birch I felled in the winter will retain the bark.

[wdwerker]

Cut the slabs but add extra for loss to achieve the final thickness you want. The rule of thumb in the lower 48 is one year of air drying for each inch of thickness, and it even takes longer the thicker it is. Of course you may not need wood dried to the level needed for furniture like most of us do. I would leave maybe 6"to 8" extra at each end so you can trim off any cracks.

[Tom King]

Sooner is better for sawing logs.

[PlaneAndDestroy]

A 4" slab wont air dry to its core, from what I've read. No matter what it"ll still be green inside.

[Eric.]

Yep ^^^ ...unless it spends decades in the loft of a barn or in a basement.  Literally decades.

[kombatfish]

That is disappointing, I will have to buy old slabs to achieve perfection. If the core is not completely dry and I leave a 4 inch slab for 2-4 years, mortise legs to make a sitting bench, in my mind it would still be strong.

4 hours ago, PlaneAndDestroy said:

A 4" slab wont air dry to its core, from what I've read. No matter what it"ll still be green inside.

 

4 hours ago, Eric. said:

Yep ^^^ ...unless it spends decades in the loft of a barn or in a basement.  Literally decades.

I see really old logs that were pushed ashore by our fast rivers here in Alaska. Maybe I should start a new thread to ask if this is a good wood to slab up. They seem dry and harder then witches snot.

I like the cracks in the wood personally, not in every project, but filling the cracks with dyed resin makes the project stand out.

 

But as a recap, what I have learned from you guys and others. Appling concepts to my Paper Birch

Rules of thumb

Cut early, burn late.

Cut in the winter to have a better chance at the bark staying on.

Paint the ends of logs.. Paint, Arborseal, Wax---- If the log is intended to stay a log

Cut and slab sooner rather than later

Better to be tarped outside then a garage with no airflow=== mold

1 year of seasoning for each inch of thickness.

 

Not sure about this one--- a slab never dries out at the core??? Why is it that a log can season with the ends painted and a slab cannot? Maybe log cores are wet too. You want to check moisture near the core and there should eventually be equilibrium. Which, according to the equilibrium chart would be about 11.5% eventually if it were to be 80F summers. could take 6 years or more to get wood I can be superbly accurate with. My skill is not quite there yet anyway.

5 hours ago, PlaneAndDestroy said:

A 4" slab wont air dry to its core, from what I've read. No matter what it"ll still be green inside.

 

[Eric.]

"Seasoned" is not the same as "dry."  Burning wood in a fireplace only requires that it not be green.  To build furniture you need between 6-10% MC, depending on your climate.  Otherwise you'll take your project inside after you build it and it'll crack to pieces.

The "year per inch of thickness" rule is a decent guideline for 1" thick material.  Any material thicker than that takes exponentially longer.  So a 3" thick slab takes much longer than 3 years to fully dry unless you live in the desert or dry your lumber in your basement with a dehumidifier running constantly.  So a better way to put it would be, "lumber that's an inch thick takes about a year to dry under ideal conditions."  And most likely it still won't be dry enough to confidently build with.  At least I wouldn't be confident.

All these reasons are why I buy properly milled and kiln dried lumber.  People always think, hell, why would I pay for wood?  It grows on trees.  This is why...because once you crunch all the numbers, you don't really come out ahead.

[toddclippinger]

35 minutes ago, Eric. said:

All these reasons are why I buy properly milled and kiln dried lumber.  People always think, hell, why would I pay for wood?  It grows on trees.  This is why...because once you crunch all the numbers, you don't really come out ahead.

BINGO!

[toddclippinger]

Several years ago I did a project where I took 15 year old 10"x10" and 12"x12" doug fir beams left over from a timber frame home and made a desk and some cabinets. 

Not having any experience with this sort of thing at the time, I assumed the material would be fairly dry. Splitting the beams open, I found the moisture content to be 5% in the first couple of inches toward the outside, but it quickly ramped up to 24% to 28% on the interior. 

Since the beams were whole trees, I halved some, quartered some, let them dry, and milled on down in stages. The whole process took place over the next couple of years.

I would have to take the material into the shop, dry it for a few months, and was able to get it down to various content of 5%-9%. I cut all the material to get as much vertical grain orientation as possible. Everything had to be frame and panel construction with consideration to movement. 

With all the consideration that I took. I was still surprised at how much the wood continued to move after construction. It would shrink, swell, and twist like no other material I have ever used. I also had a lot of loss due to the pitch content, being doug fir that was a big issue.

I have never had kiln dried material move and behave like the air dried material. To reduce liability as a business, I decided to stick with professionally milled and kiln dried material from then on. Even though I explained to the clients the potential issues of using their material, they were still not particularly happy with the amount of movement in their project. But I pointed out that I had done everything in my power to abate potential issues. 

The picture of the stacked pile did not have stickers, I actually went back a couple of weeks later, and stickered/restacked everything for better air flow and drying. Here in Billings, MT, we actually have a pretty dry climate, especially in the summer. 

 

[PlaneAndDestroy]

This topic might be dead, but...

Wood has bound and free water. Water in between the cell walls is the free water, and it's what goes away rather quickly. A seasoned log for a fire has the free water gone, but not necessarily the bound water.

Bound water is inside the cell walls themselves, and takes a lot longer to go away. This is the water you're losing when you're going from 20% down to 7%. This can't be air dried from thicker than 2", I've heard, and any timbers that are thicker are essentially still green on the inside. Apparently there's crazy microwave kilns or kilns with lasers on sharks heads that can take care of this and fully dry a piece, but that's beyond most supply options.

[toddclippinger]

1 minute ago, PlaneAndDestroy said:

kilns with lasers on sharks heads 

I will have nightmares now...

[Tpt life]

18 minutes ago, PlaneAndDestroy said:

This topic might be dead, but...

Wood has bound and free water. Water in between the cell walls is the free water, and it's what goes away rather quickly. A seasoned log for a fire has the free water gone, but not necessarily the bound water.

Bound water is inside the cell walls themselves, and takes a lot longer to go away. This is the water you're losing when you're going from 20% down to 7%. This can't be air dried from thicker than 2", I've heard, and any timbers that are thicker are essentially still green on the inside. Apparently there's crazy microwave kilns or kilns with lasers on sharks heads that can take care of this and fully dry a piece, but that's beyond most supply options.

Green and green are two different concepts. (Hmm, has a ring to it...)

I have cut very old, very thick beams that were made into structural supports 150 years ago. They are not oxidized on the inside, but they are nowhere near 10% humidity. This is in a super humid state. I assume this has to do with the shrinkage of the dry outer layer and the compression as sub zero shrinkage sets in. These are 10"x10" and 12"x12" beams in some of the softer hardwoods. This makes the never and always comments tenuous at best. There are some other factors beside the thickness. 

[PlaneAndDestroy]

So, the beams were under, or over 10%? Beams cut 150 years ago (when the tree would have stopped packing water into the cells) could very well be as dry as the environmental humidity allows, but that doesn't really say anything for how long it took for them to reach that state, or how long it takes for say a 8"x8" timber to dry all the way through. 

No hard and fast rules, but the general rule I've heard is good luck trying to air dry something over 2" thick in a commercial time frame. Barn finds of stacked and stickered 40 year old lumber and reclaimed timbers don't count

[toddclippinger]

When I did that project with the timber frame beams, I found out it is all theory until you dig into it.