Help! Fiberglassing Foamboard Airplanes

[chris398mx]

Flitetest put out a video a few weeks ago about fiberglassing over the foamboard to make the plane much stronger, crash damage resistant and waterproof. I have been wanting to try it, but they did not give very much information about what materials to buy or where to get them. I thought they may have had a follow up video on their flitetest tech channel, but I haven't found anything yet. Does anyone know what materials they are using or what materials would work to do this? What weight fiberglass and where to buy the materials in a somewhat small quantity? Any help would be appreciated. Thanks

 

[Merv]

I'm using 1/2 oz cloth from Thayercraft.
It's great for repairs & covering a plane but not heavy enough to make things with. If you want to make landing gear & fire walls you would want heaver cloth. If its something small, like a repair or reinforcement I just use hot glue. If I were going to cover an entire plane I would use polyurethane. The same stuff used to waterproof fb.

Fiberglass cloth from Thayercraft Inc - Fiberglass Cloth Supply and Education

 

[chris398mx]

I'm using 1/2 oz cloth from Thayercraft.
It's great for repairs & covering a plane but not heavy enough to make things with. If you want to make landing gear & fire walls you would want heaver cloth. If its something small, like a repair or reinforcement I just use hot glue. If I were going to cover an entire plane I would use polyurethane. The same stuff used to waterproof fb.

Fiberglass cloth from Thayercraft Inc - Fiberglass Cloth Supply and Education

Thanks for the source. In the video they are fiberglassing the whole wing to improve strength. It also appeared they are using some 2 part resin thinned with denatured alcohol to get it go on thin and even.

 

[leaded50]

resin = epoxy. Polyester who is norm for fiberglass eg boats... would eat foam. and dissolve by heatreaction on hardning.

 

[CampRobber]

You could use hardware store epoxy and glass, which is usually 6oz. However I prefer 2oz glass and I buy that and epoxy from raka.com. They sell in small quantity and you can mix and match. You can buy low viscosity resin and slow hardener if you're planning to cover large complicated surfaces.

 

[chris398mx]

resin = epoxy. Polyester who is norm for fiberglass eg boats... would eat foam. and dissolve by heatreaction on hardning.

I watched the video very closely and found out what they are using. They are using Pro-set epoxy on the video and 2 oz fiberglass from Fibreglast (241-B). I am not sure how they got away with this and didn't eat the foam. they even removed the paper during testing and put the epoxy right on the foam.

 

[The Hangar]

I’ve just started venturing into the fiberglass world myself actually. Here’s a link to my “help needed” thread, there’s some fantastic information in it:
https://forum.flitetest.com/index.php?threads/fiberglassing.65410/
I ended up ordering .75oz cloth from sig manufacturing and some polycrylic from Walmart. I just ordered the cloth a couple days ago so it hasn’t arrived yet, but I’ll update my thread once I get a chance to do some tests with it.

 

[leaded50]

I watched the video very closely and found out what they are using. They are using Pro-set epoxy on the video and 2 oz fiberglass from Fibreglast (241-B). I am not sure how they got away with this and didn't eat the foam. they even removed the paper during testing and put the epoxy right on the foam.

Epoxy dont eat foam. The fiberglass used is only the cloth. Here were i live fiberglass is an name on both polyester resin and cloth.

 

[chris398mx]

Epoxy dont eat foam. The fiberglass used is only the cloth. Here were i live fiberglass is an name on both polyester resin and cloth.

So I am confused by what you were trying to tell me. What are you saying will eat the foam that i should stay away from?

 

[chris398mx]

I’ve just started venturing into the fiberglass world myself actually. Here’s a link to my “help needed” thread, there’s some fantastic information in it:
https://forum.flitetest.com/index.php?threads/fiberglassing.65410/
I ended up ordering .75oz cloth from sig manufacturing and some polycrylic from Walmart. I just ordered the cloth a couple days ago so it hasn’t arrived yet, but I’ll update my thread once I get a chance to do some tests with it.

Great, I will check it out. the materials that Flitetest used were approaching $200. I am not sure about their comment that it was a cheap process.

 

[Merv]

Great, I will check it out. the materials that Flitetest used were approaching $200. I am not sure about their comment that it was a cheap process.

Yep, that’s why I use the oil based polyurethane. $10-12/qt at the local hardware store, no mixing, just open the can & use it. It works great for covering a plane.

 

[The Hangar]

Great, I will check it out. the materials that Flitetest used were approaching $200. I am not sure about their comment that it was a cheap process.

Yeah, all in all I’m out about $100 for the glass and polycrylic, however this is for a fairly large plane (81” WS) so I ended up having to buy 3 sheets of 36x72 inch cloth.

 

[The Hangar]

Yep, that’s why I use the oil based polyurethane. $10-12/qt at the local hardware store, no mixing, just open the can & use it. It works great for covering a plane.

Do you use that with the fiberglass as well, or just on it’s own? I’ve used it for covering planes by itself previously but I heard it wasn’t as good as water based polycrylic when using it with fiberglass.

 

[Merv]

Do you use that with the fiberglass as well, or just on it’s own? I’ve used it for covering planes by itself previously but I heard it wasn’t as good as water based polycrylic when using it with fiberglass.

Yes, I use it with fiberglass. I’ve never tried the water based poly. I need to give it a try.

I have also used plan white glue with fiberglass, it works ok.

 

[The Hangar]

Yes, I use it with fiberglass. I’ve never tried the water based poly. I need to give it a try.

I have also used plan white glue with fiberglass, it works ok.

Very intresting, thanks! I’ll definitely try that out.

 

[craigleach]

I’ve just started venturing into the fiberglass world myself actually. Here’s a link to my “help needed” thread, there’s some fantastic information in it:
https://forum.flitetest.com/index.php?threads/fiberglassing.65410/
I ended up ordering .75oz cloth from sig manufacturing and some polycrylic from Walmart. I just ordered the cloth a couple days ago so it hasn’t arrived yet, but I’ll update my thread once I get a chance to do some tests with it.

I also have be experimenting with .75 oz cloth and oil-based poly. I removed to paper from Ross foamboard and covered the foam with glass cloth and poly. The weight is the same as with the paper and the resulting foamboard is much more durable and water-proof. The foamboard cuts cleanly with an xacto knife and the sample hinges and leading edge folds look good. I'm going to try building and entire plane from pre-glassed foamboard.

Craig

 

[The Hangar]

I also have be experimenting with .75 oz cloth and oil-based poly. I removed to paper from Ross foamboard and covered the foam with glass cloth and poly. The weight is the same as with the paper and the resulting foamboard is much more durable and water-proof. The foamboard cuts cleanly with an xacto knife and the sample hinges and leading edge folds look good. I'm going to try building and entire plane from pre-glassed foamboard.

Craig

Very interesting, thanks for the info!

 

[leaded50]

I watched the video very closely and found out what they are using. They are using Pro-set epoxy on the video and 2 oz fiberglass from Fibreglast (241-B). I am not sure how they got away with this and didn't eat the foam. they even removed the paper during testing and put the epoxy right on the foam.

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View attachment 188425

as stated, epoxy and fiberglass fabric. That goes well against foam.