You recommend using the thin CA to coat the crack and then using an accelerator to cure the CA. Then you recommend using thick CA to fill the crack. What kind of bond is formed between the cured thin CA and the thick CA? Thinking along the epoxy line, the thick CA should be applied before the thin CA cures - that way all will bond into a single unit - the gap-filling thick stuff, and the stuff that soaked into the walls of the crack. I'm speculating that CA might be like epoxy in that a chemical bond (formed before cure) will be a strong bond. But if the initial thin CA application is allowed to cure - and the surface is not coarse-sanded for adhesion - and the thick stuff is applied, you may not get a good bond - and we are talking about a tension stress here. Just a thought. Terry Farrell Hey Terry, I am pretty convinced that what the thin CA glue does is stabilize the wood. It wicks deep into the wood and when it sets up, the wood's cellular structure acts as a matrix, and the glue makes it all incredibly solid. I applied some CA glue to the butt end of the jack the other day, right below the birdseye, where the endgrain is exposed. I've done this before to tighten up a loose pin. I only applied two to three drops, and in no time I saw splotches all the way down the jack where the CA glue had wicked. Try it yourself, see how far that stuff will wick into the wood. Based on my experience with CA glue I really don't think adding the thick stuff to the crack will do much. It only makes us feel better to know the crack is filled up. The real strength is in the matrix of the wood. Dean Dean May cell 812.239.3359 PianoRebuilders.com 812.235.5272 Terre Haute IN 47802
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