amiliv
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- Jul 2, 2018
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The problem: getting foam mix to the bottom of a deep and very narrow fincan. 38mm airframe and 29mm MMT. The depth to be filled with foam is 7" down to the forward centering ring, out of that fin tabs extend from about aft end down 4". So there is very narrow space between airframe and MMT.
If using 30x foam, I'd need only about 2ml of it. If I were to just squirt it in from the top, I suspect it will not flow all the way down to the bottom of fincan. That small amount, it'll just stop wherever it first makes contact with either MMT or airframe. I expect it to just push itself out the top as it starts expanding, instead of filling entire volume evenly (especially if it start expanding from the spot that is between fin tabs).
I kind of have two ideas, but not sure if either would work:
Idea 1: Buy 14 gauge 10" long dispensing needle (something like this https://smile.amazon.com/Rachels-Closeouts-Dispensing-Needle-Syringe/dp/B07MKQFVLQ). That's about fattest and longest needle I saw on Amazon. However, I'm not sure if foam mix is viscous enough to flow through it. If it is, problem solved... I can apply foam directly to the bottom of the fincan.
Idea 2: Drill a hole towards the bottom of fincan, inject foam mix through it, and attempt to quickly plug it. E.g. thick CA glue + accelerator. Or tightly wrapping it with masking tape.
Anybody else done it? The foam I'd be most likely using is TAP X-30.
If using 30x foam, I'd need only about 2ml of it. If I were to just squirt it in from the top, I suspect it will not flow all the way down to the bottom of fincan. That small amount, it'll just stop wherever it first makes contact with either MMT or airframe. I expect it to just push itself out the top as it starts expanding, instead of filling entire volume evenly (especially if it start expanding from the spot that is between fin tabs).
I kind of have two ideas, but not sure if either would work:
Idea 1: Buy 14 gauge 10" long dispensing needle (something like this https://smile.amazon.com/Rachels-Closeouts-Dispensing-Needle-Syringe/dp/B07MKQFVLQ). That's about fattest and longest needle I saw on Amazon. However, I'm not sure if foam mix is viscous enough to flow through it. If it is, problem solved... I can apply foam directly to the bottom of the fincan.
Idea 2: Drill a hole towards the bottom of fincan, inject foam mix through it, and attempt to quickly plug it. E.g. thick CA glue + accelerator. Or tightly wrapping it with masking tape.
Anybody else done it? The foam I'd be most likely using is TAP X-30.