Which sticks to wood better....acrylic, epoxy, Alumilite, etc...

[dirk martin]

I'm going to take some wooden spindles, that are still in square form (Walnut), and route some cavities into the sides.
Then I'm planning on pouring some colored Aluminite into the cavities, and let it harden.
Then I'll turn the spindles round.

My plan is to have a round spindle, with some colored spots, or decorations on each side.

My question is, what substance would be best, for pouring into those cavities?
I know Aluminite colors well, and turns fine, but it's expensive. Like $160 for 2 gallons.
Would epoxy be better?
Some other substance that colors well, and turns/sands well?

The walnut is dry.

Thoughts?

[dirk martin]

Maybe Polyester Casting Resin?
It seems to be cheaper than Aluminite.
Any advantages that anyone can thing of, of using Aluminite, over Polyester Resin?

[John M. Smith]

Poly resin shrinks when it cures. Not good with wood.

[Bruce Pratt]

System 3 two part epoxy + inlace pigments

[dirk martin]

John, the voids I'm making will be oval. Oval's about 2" long, and 1" wide, and 7/8" deep.
If I fill the oval, I'm ok with the poly resin shrinking down to about 3/4".
Do you think it would shrink more than that?

Or, do you think I'd be better off going with the 2 part epoxy, like Bruce recomends?
Is epoxy cheaper than poly resin?

[dirk martin]

I did some more research on System 3 epoxy.
Looks like it takes 3 to 5 days to cure.
I need to sand the wood/epoxy, after it's cured.
Also, I'm making dozens and dozens of these wooden objects that I'll be pouring the epoxy into, over the course of a few months.
Having to wait 3-5 days each time, is really going to drag the process out.

So, I think I'm gonna look back at the Poly Resin.
Shrinkage shouldn't be too much of a problem for me, as long as it isn't too bad.

Can someone tell me what type of pigments are used to color poly resin?

[James Combs]

Your best bet is to use Alumilite, it has a very good affinity for wood. It actually bonds at a cellar level and does not shrink. PR used as you describe may actually lift away from the wood at the ends of the ovals.

Edit: Another advantage to Alumilite is that there is no odor.

[robert baccus]

I think you may be making this too hard. Aluminite is a poly based resin--listed on their MSD sheet. All the above named resins will stick to wood and everything else not waxed. Poly resin does not shrink or we would all have very funny looking boats and bathtubs. These resins especially like to stick to fingers, lathes, doorknobs ect.

[dirk martin]

So, basically, Robert, Poly Resin does not shrink. Is John incorrect, in post #3 of this thread?


James, Alumilite may not have an odor, but do you now if it still gives off dangerous fumes? Just curious.
Carbon Monoxide doesn't have an odor, either.

[Alan Trout]

Polyester resins shrink. Polyurethane resins do not. And yes some of the Alumilites give off dangerous fumes in the form of isocyanates which can be very dangerous.

[dirk martin]

And Alumilite is a Polyurethane ?

[robert baccus]

Polyester resin is a very general term. Improperly mixed(hardener or temperature) can do anything from ignition to turning to rubber but properly used is not subject to changing dimensions. Almost all noncritical fiberglass products are made from it. Very sensitive to temperatures when mixing--I have several brushes permanently mounted in cans of hard plastic. For very highend products this resin and fiberglass can both be changed to stronger ingredients.