# Epoxy soaking into wood



## MCone (Jun 9, 2010)

I'm using the West System 105 206 combo to fill some large voids, but am finding that the wood is soaking up the epoxy and the epoxy level falls below flush before the epoxy dries. I'm thinking I need to either thicken the epoxy or need it to cure faster. Maybe I should have got the 205… Any suggestions? Thanks!

Mike


----------



## johnstoneb (Jun 14, 2012)

The wood is not soaking up the epoxy. The epoxy is slowly finding and filling the voids that are not visible. I have found in filling voids that I use a slow cure epoxy and mix enough that I can refill the void several times before it cures. You can mix and add a little more epoxy after the first application hardens enough that it no longer flows, as long as the surface is still tacky you will get good adhesion between the two applications.


----------



## patron (Apr 2, 2009)

i use epoxy with colors for some of my inlays
and 'size' the wood first (the way artists do to canvas)
i spray or brush lacquer or poly first
in the area and over the top too
i have found that some woods will 'leach' the colors
into the end grains and any open pored grainy woods
the sealer keeps this from happening

and as above from bruce 'top off' as needed

a hair dryer or a spritzer bottle of lacquer thinner
for about an hour (sit and read a book while attending this)
to 'burst any bubbles as they come up 
(they happen from the heating and filling air voids)

over fill the space as you do this
so when you sand the surface is full and bubble free

i use craft paint from wally world 
it comes in small bottles

trying to get the right mix after the fact
is very hard to match

it only takes a small amount of color to do
(mix well and add drops of color 
till you get the shade you like)

if you don't burst the bubbles as they come up when you sand 
(sometimes you need to wait a couple of days
depending on the weather and moisture)

you will have a crater full of voids to try and match
easier to mix more to start and get a good result


----------



## Ger21 (Oct 29, 2009)

make sure it's not leaking through. If it is, seal the back with masking tape.

Brush on one heavy coat, and try to make sure all surfaces are covered. Wait until it starts to gel, then mix another batch and fill completely.


----------



## MCone (Jun 9, 2010)

Thanks, guys! One quick question. You say to do the second coat when the first is still tacky. Does that imply that if I wait until the first coat is completely dry that the adhesion won't be as good?


----------



## DrDirt (Feb 26, 2008)

> Thanks, guys! One quick question. You say to do the second coat when the first is still tacky. Does that imply that if I wait until the first coat is completely dry that the adhesion won t be as good?
> 
> - MContemp


Yes - much like polyurethane, i needs to either be "monolithic" as one piece - so wet to wet.

Or you need some kind of roughed up surface for adhesion, or the topping off can/will peel off the cured surface


----------



## kelvancra (May 4, 2010)

Like Patron, I found I had to seal the wood before I applied two part mixes.

I used to buy my epoxy in the five gallon containers (five gal of part A and five gallons of part B). Said another way, I poured a lot of resin. From the get go, I discovered I had to seal the wood, before applying any final coat. That was even with the thicker two part mixes I used.

The two to one epoxy I buy by the gallon-half gallon container flows even more, so it's even more critical I seal before a final coat or pour.

The reason for sealing was two part:

Once I poured the resin, and if the wood was not sealed, air would escape from the wood into the resin and I had to act quickly [and keep acting] to remove bubbles.

If the wood was at all punky, the resin would soak in and I'd get low spots requiring a second pour. Technically, this might be better described as Bruce describes it, but it remains sealing made a night and day difference.

When I was working with news or other print, I used the same thing I used to glue the item down to seal it against bleed through - Elmer's glue. If I used resin, poly or anything else and applied it too heavy, it saturated the print and destroyed the job, because the print on the other side showed. The glue didn't do that and stopped the resin from doing it.


----------



## MCone (Jun 9, 2010)

Kelly and Patron,

How do you seal properly if you can't see down into the void? In my case. I have deep cracking on the edge of a 1.5" thick board.


----------



## dschlic1 (Jan 3, 2013)

Believe it or not West system epoxies are designed to soak into wood. There will be penetration into the wood fibers during cure.


----------



## Unknowncraftsman (Jun 23, 2013)

Epoxy does soak in that's why I don't like it for glue joints a dark glue line can sometimes show that only gets darker with a finish.
My first time I filled a knot with epoxy I taped the back side but there was a void that leaked epoxy all over the floor.I just kept mixing more and pouring thru the wood on the floor.
It wasn't funny at the time but now it is.


----------



## 000 (Dec 9, 2015)

The very few times that I have done it, I built a small dam around the area being filled, then sanded it flush after it set up.
Took care of shrinkage.


----------



## patron (Apr 2, 2009)

> Kelly and Patron,
> 
> How do you seal properly if you can t see down into the void? In my case. I have deep cracking on the edge of a 1.5" thick board.
> 
> - MContemp


the lacquer or poly is much thinner or fluid
than the epoxy
that seal coat sucks right in
i sober it on
(and the top too)
let it suck in and dry good

when you sand the epoxy
go down to the wood
there won't be any discoloration 
from either the seal coat
or the epoxy


----------

