# Stabilizing and casting questions



## Isaac

I've wanted to try stabilizing for a while. Now, after reading some of the threads on this forum, I'm left wondering if I should instead be looking at casting, or even stabilizing _and_ casting. I have a few questions about the processes before I head one way or the other. 

A little background on what I want to do is probably in order, so here goes.

I make backsaws. Some of the woods that I use (or would like to use) for handles would benefit from increased strength. Increased dimensional stability is not needed, nor is it the goal, but would be a positive. I am not interested in coloring any of the woods. 

I like to use all types of woods, but am somewhat limited by needing to use sound wood. I would love to try more spalted and figured types. I'm not thinking of using wood that is 100% punky; more like a patch here and there. From what I can gather, stabilizing is more appropriate for this since there aren't big voids to fill, just lots of empty cells. Is that correct? In this case, does stabilizing increase the strength of the wood?

One of the woods I frequently use now is walnut crotch. It is a tough wood to dry without checking or cracking, which really limits my selection. If I have a piece of this with a hairline crack, will either stabilizing or casting fill in that void and act as a glue or reinforcement? How wide does a crack need to be before you would switch from stabilizing to casting?

One last question for now. Once the wood is stabilized or cast, do you put on any finish after sanding, or is the cured resin all you use?


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## Cody Killgore

Yes, stabilizing will increase the strength of the wood. Whether it is punky or not, it will typically increase the strength to some degree (much moreso if punky). 

As far as filling cracks...I would not count on stabilizing to fill any of them. It MIGHT fill some very very fine hairline checks but you cannot count on it to do so. It drains out of any voids/cracks that are in the wood.

As far as casting goes... the casting resin will not actually enter the wood. It simply fills in all holes/cracks/voids that may be there (as long as there is a path for it to take from the outside of the blank).

For finishing, I've done it either way. It really depends on the wood and the final finish desired.

I picked up both stabilizing and casting for that reason. I have many blanks that have some large-ish cracks in them that I wanted to fill. Casting makes it easy to do so, while stabilizing gives me the extra strength in soft and punky woods.

Reactions: Agree 2 | Informative 1


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## BangleGuy

Isaac, I think it would be better stated that stabilizing makes wood harder, but not necessarily stronger. If you rely on wood to flex, I would guess that stabilizing also makes wood stiffer, which may or may not be desirable. If you are going for strength (tensile or bending), then resin casting to fill voids and cracks is the way to go. Stabilizing resin is too brittle to add a lot strength.

Also, some wood species stabilize much better than others. Walnut does not stabilize well using simple vacuum and atmospheric pressure for resin infusion. Maple is a great all around species for both strength and ability to accept stabilization. You can learn more about polymerized stabilizing resin (Polymerized Methyl Methacrylate - PMMA) on Wikipedia.

Reactions: Informative 1


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## TurnTex

Eric,
I hate to contradict you but PMMA stand for poly methyl methacrylate not polymerized methyl methacrylate. PMMA has nothing to do with stabilizing other than it is a similar chemical. PMMA is the chemical name for Plexiglas and other acrylic solids. You may be thinking of MMA (methyl methacrylate) which is different chemistry. MMA is the old school stabilizing resin and is used in other applications including the medical field and used to be used for adhering fake fingernails. Modern retail stabilizing resin do not contain any MMA and instead, contain methacrylate esters which is again different chemistry. MMA is highly flammable and considered hazardous materials. Modern retail stabilizing resins do not contain any MMA and are usually not flammable or considered hazardous materials, at least the one that I am most familiar with. :)

Reactions: Like 1


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## BangleGuy

Well, I stand to be corrected. I have read plenty on MMA stabilization of wood, and believe that cross linked MMA is PMMA (or simply poly or polymerized). I assumed that cactus juice was MMA, but you are the expert on that subject!


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## Isaac

Thanks for the info, guys. 

Is it fair to summarize by saying that stabilizing fills the cellular spaces, while casting fills in where wood is missing? 

And one followup question - how small of a crack will casting fill?

Reactions: Agree 1


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