Reddit reviews West System 406-2 Colloidal Silica 1.7 oz.
We found 1 Reddit comments about West System 406-2 Colloidal Silica 1.7 oz.. Here are the top ones, ranked by their Reddit score.
406 Colloidal Silica is an epoxy thickening additive used to control the viscosity of the epoxy.Prevents epoxy runoff in vertical and overhead joints.Creates a smooth mixture, ideal for general epoxy bonding and filleting.Used to improve strength, abrasion resistance, and consistency of epoxy fairing compounds.Cures to an off-white color.
The longest cure you will be able to find at a hardware store will most likely be a 30 minute epoxy. Generally from what I've seen there will be a 5, 15, and 30 minute option. The reason I am saying get a long kick epoxy is because once you mix in the additive the reaction is going to increase pretty exponentially AND be very exothermic. I.e. you're not going to be able to work with it for very long and its going to get hot (depending on the amount it could get so hot that it starts to smoke).
As far as additives go, I have used just about everything out there from milled glass to chopped kevlar. In your case the filler is there so that the epoxy stays where its supposed to be and so that you get a consistent fill (no voids, etc). When you mix in a fiber based additive the epoxy (texture, spread-ability, etc) is going to behave very differently than if you mix in a powder. In your case the main benefit I see with using a powder vs a fiber is that you are going to get a better finish with a powder vs a fiber. With the fiber you will always have some strands that will go where you don't really want them too and when you're machining the epoxy out I could see you potentially snagging an errant fiber and popping the whole epoxy fill off (all depending on the size of your fiber)
The reason I suggest Colloidal silica is because it is a very commonly used bonding additive. Here is a Link to a supplier that will have a lot of different options with descriptions of whats out there. I've used almost every westcoast product. The 404 and 406 are great for bonding structural members. The 404 works better for impact and cyclic loading situations. 406 is more generic. If you are going to order something you could probably get a smaller quantity from amazon, but that website should give you an idea of options. CST is reputable and I have purchased a lot from them. I haven't used any of their epoxy though. My lab uses a different laminating resin. I am also not a huge fan of micro-balloons. I find them more difficult to work with and weaker than silica. The main reason they are used is because they are very light weight.
Ultimately, I don't really know how any of it would work out in this application. As you are well aware, its very difficult to put back material when you take too much.
Edit: Amazon Links for some 404, 406, and a 30 min epoxy.