Ok, it's not baking soda.

The kit "RapidFx dual adhesive system" has two components: Adhesive and Welding Powder. Adhesive appears to be a standard low-viscosity cyanoacrylate.

Welding powder is a noticeably heavy white powder that seems to flow almost like a liquid in the unopened bottle (a 25 ml plastic bottle/spout of the adhesive weighs 35 grams; the similar bottle of the powder weighs about 50 grams). The MSDS I found online reveals it as 99% glass, 1% silica. Under the microscope it is almost exclusively clear beads, approximately spherical, almost all between about .003 and .006 inches diameter. Many (most ?) of them had a tiny bubble near the center; I doubt that it affects things except to reduce the density by some fraction of a percent. It is possible that the beads were coated with something. There was an occasional filament but they were clearly artifacts of production, not an intentional part of the material.

So -- this is a filled material, not a reinforced one. I would expect it to be quite strong in compression but less so in tension. Tensile strength might depend strongly on the adhesive bond to the glass beads.

I'll do a few rough comparison tests between glass and baking powder fillers when I have a chance.

Yrs, d

At 08:23 PM 5/4/2015, sailingfc @dslextreme.com wrote: >Haven't tried this stuff, but it looks to be the same as cyanoacrylate >(Crazy Glue) and common baking soda. I've used this combination for years. >Just sprinkle baking soda on the bead of liquid and you have a rock hard >glue bead. Don't use the gel crazy glue, it's too thick and won't absorb >with the baking soda, which will leave you a blob of crazy glue with no >baking soda "dissolved" in it.

Great to know. I have some of the other stuff on order, if it's the same I'll cuss and let you know. Either way I'll let you know. They also have some light-cured stuff, comes with a UV flashlight.

Yrs, d