Camillo

Well Known Member
Hallo. I am completing my fiberglass parts and wanted to know how to finish them.

I layed several layers of fiberglass and now would like to fill the medium areas and then fill the small holes.

From a different thread, I understand that I have to fill the first with flox and the latter with SuperFil.

My question is: since I also have "Quick Fair Epoxy putty" http://www.aircraftspruce.com/catalog/cmpages/quickPoxy.php , what this is for? Spruce places it among the "epoxy" but from the description it seems like the SuperFil.

I used Quick Fair fro empennage fairings. Do I have to use it also for canopy rear skirt or it is preferrable to use SuperFil?

Thanks.
Camillo
 
I don't think you want to use Flox, micro balloons maybe, but not Flox.

One trick that seems to work well is to put just pure slow hardening epoxy on and wait some time and then come back and using a squeegee, press it in to the holes.

Of course you will want sand the fiberglass first, to open up any holes you might have.

Best of luck.
 
Quick fair appears to be epoxy already mixed with microballoons. You mix the two parts together and squeegee on the part, then sand. If you already have the west system epoxy and a bag of microballoons you can just mix up your own paste.

Flox is used in structural applications. An example is if you need to lay glass into a 90 degree angle. You mix up the flox/epoxy paste and fill the corner. Then you would lay the glass over it and make a radius instead of a sharp 90 degree angle. The radius makes the angle much stronger than a sharp angle would be.

Microballoons are used more as a filler because they are very light and easier to sand. An example is a part that has low spots or a rough surface. You mix up the paste and spread similar to how you would spread bondo type fillers. Once it sets you can sand it
 
Another product worth mentioning is West System's fairing powder. It mixes with epoxy and is easier to sand than microballoons, at least in my experience.
 
Thank-you. I hope I have understood.
SuperFil is a good product. I am just applying it over the cured fiberglass.
Today, I will sand it and pass a pure epoxy layer.

QuickFair should be a similar product, but I am using SuperFil only, just to be sure.
 
West system guides

The West system guides are very good - give lots of information on how to use the different types of fillers to best advantage.

http://westsystem.com/ss/use-guides/

Being an ex (amateur) boat builder I used these products as I was familiar with them and in the UK its easier to find marine suppliers than aviation suppliers.

I think Dan H's work looks really exceptional and I have learned a lot about epoxy work from his posts.

Chris
 
Morning Dan, quick question. I have West Systems 410 microlight fairing filler. Is that a product that can be used instead of micro balloons or are they for different purposes?
 
Morning Dan, quick question. I have West Systems 410 microlight fairing filler. Is that a product that can be used instead of micro balloons or are they for different purposes?

Jim, I've never used any of the West fillers, but yes, 410 looks like an expensive substitute for micro.
 
And the operative word is expensive. That's the info I was looking for. BTW the 410 works great and sands like easily. Thanks for the help, Dan. After reading all the posts you and Darwin put on the VAF I tackled my Horizontal stab tips. I taped the seams over the pop rivets and faired them in. It worked better than I ever thought it would. I have them primed with epoxy primer and you would think it is all one piece. Again many thanks for taking the time to help your fellow builders.
 
West Fillers

From their web site (note the comment on temps):

410 Microlight? is the ideal low-density filler for creating a light, easily-worked fairing compound especially suited for fairing large areas. Microlight mixes with greater ease than 407 Low-Density filler or microballoons and is approximately 30% easier to sand. It feathers to a fine edge and is also more economical for large fairing jobs. Not recommended under dark paint or other surfaces subject to high temperatures. Cures to a tan color.
 
Note that...

From their web site (note the comment on temps):

410 Microlightâ„¢ is the ideal low-density filler for creating a light, easily-worked fairing compound especially suited for fairing large areas. Microlight mixes with greater ease than 407 Low-Density filler or microballoons and is approximately 30% easier to sand. It feathers to a fine edge and is also more economical for large fairing jobs. Not recommended under dark paint or other surfaces subject to high temperatures. Cures to a tan color.

...the temperature limit is probably due to the WEST epoxy and not the 410 micro balloons.

Boat hull temperatures tend to be somewhat less due to all that water...:)
 
Last edited:
...the temperature limit is probably due to the WEST epoxy and not the 410 micro balloons.

Nope, it's the filler. We use the west system all the time with no problems but engine heat will crack the 410 filler. Had to dig all mine out and redo with regular micro to stand up to the heat. Works fine out away from the engine and exhaust.