[Av8torTom]

Hello Folks,

I'm getting ready to fiberglass the fairing on the front of my tip-up canopy. Vans website recommends using microballoons to thicken the epoxy for gap filling. Others here have recommended cotton fiber flox.

Pros and cons for each? I suppose for just gap filling around the edge of the windscreen it's not hugely important, but I'd like to hear others' opinions.

Thanks,

Tom

 

[airguy]

Flox to fill the gap and cover the tabs holding the windscreen in place, microballoons over that to give a clean smooth layer.

 

[Gary 40274]

Properties

Flox to fill the gap and cover the tabs holding the windscreen in place, microballoons over that to give a clean smooth layer.

Think of flox/chopped fibers as rebar. Think of micro as fluff. Use rebar where you want strength and fluff where you want easier sanding and for filling

Gary Specketer

 

[Av8torTom]

Thanks

Thanks guys. I guess my question is do I need rebar or can I get away with fluff for filling in that windscreen edge before I begin laying in fiberglass. I have a fair amount of experience with fiberglass and epoxy - flox is a PITA to sand compared to microballoons..

 

[rightrudder]

I used a combination of both. The trick is to use the flox sparingly....lay a bead down in the gap between the windscreen base and top skin, then smooth it down flush with your finger so little if any sanding will be needed. After it sets up, apply a more generous fillet of dry micro. Remember to tint both the flox and micro with black pigment for a better appearance from inside.

Here's a pic of the dry micro fillet, just before application of the fiberglass. You can see that the retaining clips are almost completely buried at this point.

 

[rvbuilder2002]

- flox is a PITA to sand compared to microballoons..

And that is the reason that a micro mixture is specified. There is no benefit to flox at this location. The additional strength gained by bonding flox to the edge of 1/8" thick acrylic would be very minimal.

The only purpose is to fill the void so that the glass layup doesn't sag into it. A micro mixture works great for that.