To wet or not?

[beekeeper]

Discussing this here to keep from hijacking Darrells Northwind post any further.
viewtopic.php?f=2&t=8162&start=60

Bee
Nail holes want open back up,
when you wet wood it lets the wood go back to its original shape , you can steam a gunstock that has a dent and it will come back out. Nail holes are not drilled they are forced into the wood
so water lets them return to there original position. There is another benefit from wetting wood ,it stands the surface fibers up on every wetting letting you get a much smoother finish when you sand and epoxy.
As thin as a strip boat is a couple hours in the sun and you are bone dry ,are at least within acceptable limits, moisture content is never at 0 .
Ron

I understand what your saying about the water swelling the wood fibers and causing them to stand proud. The hole is still there (torn away fibers won't reconnect together), just not as big or obvious. I'm not sure gunstock smooth is necessary for wood saturated with epoxy and covered with glass. I would think the leveling and build up of the epoxy and fiberglass cloth would cover any fibers not removed by adequate dry sanding.
The information I have found about wetting and redrying indicates kiln dryed wood will absorb water and will not return to that moisture standard, unless kiln dryed agin. Air dryed levels may be adequate but the redrying could cause the wood to bend, crack, or twist. A "couple hours in the sun" could cause problems. The rule of thumb for air drying wood calls for one year per one inch of thickness. It could take three months to safely (no warpage) a .25" board.
It would take a moisture meter and some test to know how much of an issue this may or may not be. If there have not been any (known) problems it may be ok. I will stay with the wisdom of keeping the wood as dry as possable. I don't want to take the risk. For me the chance of a problem out weighs any benefits of wetting. I'm not saying anybody is wrong. Just asking the questions and expressing my thoughts.

beekeeper

 

[Kayak Jack]

JD, my practice tends to support part of your reasoning. Covering a slightly rough piece of wood and a perfectly smooth piece of wood with glass and epoxy results in a finish much more dependent upon the glass and epoxy than the underlying surface of wood.

Now, as to wetting wood. I think that for raising "hairs", the wood can be just misted or wiped, and is not saturated. Therefore, we're not talking kiln action or long periods of time to redry it. Not that much water was used in the operation. And, subsequent sanding will both remove part of the dampened wood, and thus open up deeper wood to drying air. Even heavy wiping and pooling of water is unlikely to put water through the first glue layer.

All that being said, I too am in favor of keeping it dry, and see little advantage to wetting it in the first place if it is to be covered with glass. If I am seeking a furniture finish on wood to be varnished, that is something different.

Others will have different opinions, I'm sure.

 

[beekeeper]

Jack I may be just splitting hairs. I don't know how much water it takes to swell brad holes, nor how much the moisture content might rise, or how much it might dry in the sun. My guess is the wood would have to be saturated to close holes. Very little moisture is needed to raise wood hair fibers for sanding and probably not an issue.
I was thinking in terms of soild wood construction (strip or plank).

beekeeper

 

[tx river rat]

I have done 15 boats this way with no problems plus most of the builders I know do the same thing.
I use to build a lot of wood bows and the moisture content was very important, but they were air dryed . you never built a bow from kiln dry wood that would shoot as well it was to brittle. Kiln dry wood picks moisture up from the air just like any wood. The figures you are quoting are for green wood and air drying
The wetting closes the nail holes to where you can hardly see them, and that is what you are after, also any dents will swell out , in fact Darrel and I both use as hot a water as we can get to completely soak our boats so it penetrates as deep as we can get it and do it several times so the are soaked as deep as we can get them,if you want to swell the holes inside you need to have it soaked all the way thru if you can
as far as the finish on a boat and the final sanding not making a difference , would you put a finish on a boat without wiping it down with a tack rag are put a handful of wood flower on the hull and the try to put the finish on. The smoother the wood the smoother the finish.
Gunstocks wooden boats violins its all the same.
Ron

 

[swampwood]

Ron,
I can see the point for small punched holes, but you drilled holes for the tie wraps and water will not swell the wood enough to fill them. Even the punched holes will open up after the water evaporates.
To me water is an enemy of wood and should only be used to raise the grain, not swell it.

 

[beekeeper]

Ron,
I can see the point for small punched holes, but you drilled holes for the tie wraps and water will not swell the wood enough to fill them. Even the punched holes will open up after the water evaporates.
To me water is an enemy of wood and should only be used to raise the grain, not swell it.

Darrells boat was strip built and probably had only brad holes. Holes big enough for wire ties would have to be filed with epoxy and wood flower to close.
Wetting enough to raise the grain is not a concern. I have reservations about soaking it completly to swell holes and drying it quickly. I think we just don't know long term. Ron has not had any known problems. I think most of his 15 boats were plywood. That would be a different deal. It has layers of wood, and glue. It is "suppose" to be made to be water resistant. I would not wet luan even to raise the fibers.
In the big picture we are all probably just splitting hairs. For now I will stay in the camp of not soaking.

beekeeper

 

[Kayak Jack]

<SNIP> For now I will stay in the camp of not soaking.

A safer, less laborious path. If it ain't broke, don't fix it.

 

[tx river rat]

I dont wet ply
bit nearly all my boats have some solid wood on them.
We all have our way to do our builds and mine is just my way ,and most of the builders I know personally.
As far as brad are naill holes opening back up , it doesn't happen ,when you have a couple extra strips try it .
Ron

 

[swampwood]

Ron,
Bet I can see everyone of those brad holes when the boat is finished.

 

[tx river rat]

Dont bet on it
I want go to the extra steps it takes to make them completely invisible, but they will be way less visible.
Bee ask the question ,I gave an opion from my experience with several solid wood built boats and what I have learned from builders that have built more boats than we will ever build.
Take or leave it.
Ron

 

[seedtick]

on the subject of wet or not wet, y'all may be comparing apples and oranges

Ron has historically (if i remember correctly) used vinyl ester (polyester) resins on his boats while most everyone else has been using epoxy.

The hardner for vinyl esters is typically methyl ethyl ketone, which is a polar compound

Water is also a polar compound.

Polar compounds inhibit the epoxide reaction. Some folks make a thin epoxy by adding a bit of acetone (also a polar compound) to their epoxy. The acetone not only thins the epoxy but it slows the reaction, thus keeping the epoxy mixture from setting up as quickly and allows for better penetration into the wood. The downside to this is that the cured epoxy is not as strong as the unthinned epoxy.

Now i'm not saying that you can put any type or amount of polar compound in a vinyl ester system or any type or amount of polar compound in epoxy for thinning but i believe that the vinyl ester system is more forgiving of small amounts of water than an epoxy system

 

[tx river rat]

I did use poly rison but my last three boats have been with epoxy
Ron

 

[beekeeper]

If there is moisture in the wood (more than air dried levels), what happens after the wood is (sealed?) saturated with epoxy?

beekeeper

 

[rhutchinson]

This mules about wuuped to death, but I'm going to throw my experience in re the nail holes. When I worked as a finish carpenter and we made an oops in the door or window trim with the hammer face (it happens once in a while) if you put a thumb full of spit on it in 20 minutes it was gone and didn't come back. The wood fibers swelled back to normal after being mashed and stayed that way. My 2nd experience is when I was a kid my father taut me that if I had to nail close to the edge of a board or any other place it was likely to split, to take the hammer and blunt the point of the nail so it would break the wood fiber and push it through rather than just seperating the fiber and causing a split. This I have done for 40 yrs. and it works.
These comments are just my experiences and aren't intended to stir the poop pot!

Richard

 

[tx river rat]

I know from playing with moisture meters that on any given day wood has moisture in it , a humid day more that a hot dry day.
What happens on the boats I have done this way and the ones that I have seen done this way
is nothing happens.
I am not arguing with you just stating what I have done and what most of the builders do that I know.
Ron

 

[oldsparkey]

I have to agree with Richard........About the poor , beaten , Mule so let me whip him again.

Things that I have found out.
1. Everyone has a different way to build there boats. It works for them and that is all that counts.
2. Explaining the different ways is a good way to share knowledge about what works for you.
3. That information lets everyone decide weather they want to try it or not to........There choice.
4. A saturation coat of epoxy will fill the wood fibers and make some stand up , a light sanding gets rid of them and no water is added or applied to the boat.
5. That epoxy saturation coat also seals the wood to stop the wood from getting more moisture or letting the moisture out.
6. Wood in Arizona will be a lot drier when a boat is made due to the lack of humidity.
7. Wood in Florida will be wetter due to the humidity and heat when making a boat , especially if it is made in the open. ( outside a shelter or even inside a workshop that is not A/C controlled ) .
8. No matter what the moisture contend of the wood is , when it is epoxied and glassed all the way around it will stay that way for a long time. Can you say .... Sealed in a weather/air proof container, something like the air tight Tupperware containers.
9. My boats get wet only after they are made and in a river/lake but that is just the way I do it.

Disclaimer to # 9......
That is not counting the perspiration that is applied ( not intentionally ) to the boat while making it in the summertime heat.

 

[beekeeper]

Ron
I am not arguing or saying you are wrong the way you are doing it. I am only asking about what happens, and what may be the effects. I often ask why and what if. It keeps me from going down a path blindly, or helps me understand why some things may be ok, even when it doesn't seem right to me.
Since the mule beating issue has been raised, :roll: :wink:and I like mules, I will make two points and bow out.
1. Wetting wood a little to raise the fibers shoud not cause any problems.
2. Saturating wood completely to swell holes concerns me. The purpose is to disguise the holes, but the chance of extra moisture remaining in the wood is too high for me. There are other ways to disguise them, or use a stapleless method.

beekeeper

 

[tx river rat]

Bee
It is for more than closing holes, it lets the wood go back to as close to natural as it can be , relieving dents , swelling holes, tighting cracks you have plus it will show you any imperfections that are going to show up with the epoxy on it.
The moisture content is not anything to worry about , what happens if you get a scratch in your boat and moisture gets inside the glass , the boat isnt going to self destruct ,you are going to let it dry for a couple days then fix it and go about your business.
I have done this on 15 plus boats with no problems, some have been luan one marine ply and now 4 strip boats , and seen 25 or 30 other boats done the same way. It just doesnt matter
As far as the nail holes it does help them , but I build boats for hard usage.

Ron

 

[jdupre']

From what I've read, there are two kinds of moisture in wood : moisture inside the cells and moisture between the cells. The "one year per inch of thickness" rule generally applies to green wood. This rule mostly is to take care of moisture inside the cells which is very slow to dissapate. The moisture between the cells is much easier to remove. I've seen the analogy of a pool full of water bottles. Drain the pool and take the tops off of the bottles. The water around the bottles will evaporate in a few days. The water in the bottles would take months or years.

A quick steam or splash of water will not find it's way back into the cells easily. Water that surrounds the cells will dissipate quickly. Wash a wooden cutting board in hot water and it will be dry the next day. I would guess if you soaked that same cutting board in hot water for several hours, then it would take a few days to dry out.

Joey

 

[WDfrmTN]

Just to clear (or muddy :twisted: ) the issue, plywood is a composite. It's just that plywood has become so common as "wood" that we forget and generally refer to "composites" such things as fibreglass, chemical synthetics, etc.