vasek

My Feedback: (4)

hi,

i have a glassed wing that should be ready for priming, however the job has not been done properly...

some areas of the trailling edges had been sanded through the glass finish and other sections still require some filling in before priming (wing, stab & rudder)

i need some step by step instructions on how to fix this problem, including the best materials to be used to keep the sufaces as light as possible

thaks for any tips in advance,
Vasek

Campy

My Feedback: (1)

I suggest the following:

Sand as much of the glassing job away as possible without getting too badly into the wood.

If the low areas can be seen without a primer coat, fill and sand them with a lite weight filler, if you can not see them just proceed as indicated. You will get the highs/lows further on.

Put on ONE coat of a sanding sealer. Whether or not you do the whole thing will depend on the amount of bare wood and filler area you see. You may be able to get away with just "spotting" them if it isn't too extensive.

LIGHTLY sand the sanding sealer with 220 or 320. All you want to do is remove the fuzzies.

Use 1/2 OZ (.5 oz ) fiberglass cloth. Lay the cloth over the wing (stab, fuselage, elevator, etc ) and using a WATER BASE polyurethane and a FOAM brush apply a coat of polyurethane to the fiberglass. You want to work from the center of the cloth out to the edges of the cloth. Brush in ONE DIRECTION only. Make sure any overlap areas, overlap by at least 1/2". DO NOT SAND AT THIS POINT.

When this dries, apply a coat of water base polyurethane mixed with microballoons to fill the weave.

Wet sand this with 220. BE CAREFUL, you can easily sand through the fiberglass cloth.

CAREFULLY check the fiberglass to make sure the weave is filled. If it isn't filled, give it another coat of poly/microballoons and wet sand again.

Now give it a LIGHT coat of primer and block sand to show up and highs/lows. Fill any lows with lite weight filler.

Put ONE coat of sanding sealer on any filled areas and LIGHTLY sand.

After all this is done, spray ONE COAT of water base polyurethane on the surface. When it dries you will be ready to prime, detail and paint.

vasek

My Feedback: (4)

thanks Campy,

will do, your instruction are exactly what i was looking for!

if you could specify the sanding sealer you are using and if you know a supplier for the 1/2 oz cloth (can't get it i n the LHS) it would be helpful,

Vasek

Campy

My Feedback: (1)

The 1/2 oz fiberglass cloth I usually buy from E-Bay.

Any brand of sanding sealer will do fine. I used MinWax because I had a can of it already. All you are doing with sanding sealer is sealing the balsa so it doesn't soak up too much poly.

vasek

My Feedback: (4)

thanks Campy for your help

Vasek

Fighterpilot

My Feedback: (2)

What did you use to originally glass the wing? If you used epoxy resin, just add a piece of cloth over the spot where you sanded through and reapply with the same resin. Do this over all the spots you sanded through. Once this is dry, apply a second coat of resin over the entire surface and allow to dry. Then block sand until smooth being careful not to sand through the glass cloth again. You should never sand over your glass cloth application until after you have applied a second coat of resin. It's no be deal, just replace the glass using your resin to apply, let dry, apply second coat of resin to entire surface then sand. You will never see the patch job after you sand the second coat of resin. If for some reason you can still feel or see the patch and are afraid to sand anymore, prime the wing and then sand off almost all the filler primer with a block. Do not sand by hand, use a block which will sand off the high spots and leave primer or resin in the low spots.
Good luck.

vasek

My Feedback: (4)

pilot, i did not sand through the glass job myself, i have purchased the plane the way it is now and i assume it's epoxy

your idea souds easier than sanding down all the surfaces... could i use the MinWax insetead of the epoxy for the added patches? it would be easier for me (am allergic to epoxy)