I'm not sure if this should go in this forum or the building section but hear it goes.  My brother in law had a problem with his fillets (Super Fil) not sticking to the plastic canopy.  He cut the canopy off and bought a SIG canopy (should have mentioned the plane is a Brodak Legacy kit).  He tried a test and the material isn't sticking to this canopy either.  Has anyone had this problem and/or a solution?  I'm wondering if he maybe got a bad batch of Super Fil.

Thanks,

James

Put pin holes along the edge of the canopy where the fillet will cover it.   

Now I ask, how long has the fillet set on the canopy?   I have never had a problem with fillet material after sanding the edge of a canopy.  Also cleaning real good with acetone or alcohol.   

The brown stuff is phenolic not glass like the white stuff.  Here is a comparision test between the two:

http://www.ez.org/canardpages/pages/chasingmars/Misc/Phenolic%20vs%20Glass%20K20%20micro.pdf

That's odd. I agree that it must be a bad mix. I've never had problems with this. Rough the canopy where it contacts the plastic, but that's about it.

Hi Randy,

I agree that it was probably a bad mix; not by the manufacturer (Poly-Fiber) but by the user.  Like any epoxy or polyester based filler each component must be thoroughly mixed before taking some out of the container for mixing together.  The reactive components of Part A & Part B will settle out to the bottom of the containers and if not thoroughly mixed prior to taking some out for mixing together they will not cure properly nor will they adhere to a substrate the way they will if properly pre-mixed.

When I use Super-Fil I just use a paint stirring stick and stir each component up from the bottom over & over until the fluid on the bottom is thoroughly mixed in with the rest.  Be careful (stating the obvious here) that you don't use the same stick for both Part A & Part B.  The tan stuff (Part B) is the easiest to get mixed; the blue stuff (Part A) takes some time but the Super-Fil is such a great product that it is worth the time & effort.

If I am using the Super-Fil relatively frequently then the pre-mixing only needs to be done once every couple of weeks or so.  If it has sat on your shelf for a month or two then it should be pre-mixed.

One other thing about mixing a batch of Super-Fil to be applied: it can be mixed 1:1 by weight or by volume.  The most common way, used by most people I'd say, is by volume...that is take some Part A on the end of the mixing stick & wipe it on the mixing board then (of course using a different stick) take some Part B on the end of the mixing stick & try to wipe the same amount next to the Part A.  This works pretty well for me & the product does not seem to be terribly sensitive to proportions, but it could probably be overdone.  If you have an accurate digital scale it would be a good idea to mix by weight.