Author Topic: Fiberglassing fuselage (Read 1761 times)

Bob Reeves · « **on:** February 11, 2010, 06:39:08 AM »

Planing on using .5oz fiberglass put down with finish resin on the fuselage of my latest build. This is the first time I've used this method and am wondering. Where and what to do with the overlaps? When using carbon and dope I just cut and piece it together as needed as the joints sand real easy. I normally make a wing cut out and lay a piece on each side then cover the top and bottom as needed. If I do this with fiberglass and epoxy I'm going to end up with joints that might be a bear to sand flat. Any tips?

Thanks,

Allan Perret · « **Reply #1 on:** February 11, 2010, 07:21:15 AM »

Dont know the answer to your question, but have one about your carbon matt method.
Are you saying that you overlap the pieces of matt and they are easy to sand out flush ?

Paul Wood · « **Reply #2 on:** February 11, 2010, 07:22:27 AM »

Bob,
The trick to fiberglassing is not how much epoxy you put on, but how much you take off. Brush a thin coat of epoxy on the bare wood, then lay down the glass. Brush another coat of epoxy on and then use lots of paper towels to press the epoxy into the weave. Use the towels to soak up as much epoxy as possible. The seams will smooth out and the primer will take care of the rest. I don't try to cut the glass around areas like the wing holes until the epoxy has set up for 24 hours. Then you can lightly sand along the opening with 320 grit paper and it will smoothly cut the glass away. Use 320 grit to gently sand the epoxy after it cures, and clean well with alcohol prior to priming. Use latex gloves to keep the epoxy off your hands and hand oil off the epoxy. Wear a dust mask when sanding. Nasty stufffor the lungs! Good luck.

Paul

Bob Reeves · « **Reply #3 on:** February 11, 2010, 07:38:26 AM »

Quote from: Allan Perret on February 11, 2010, 07:21:15 AM

Dont know the answer to your question, but have one about your carbon matt method.
Are you saying that you overlap the pieces of matt and they are easy to sand out flush ?

Yes, but remember I usually use dope. This time I'm using epoxy as I plan to paint it with Nelson paint which can't be put over dope. My test pieces showed fiberglass worked better, less filling and sanded out better (not necessarily easier) than carbon when put down with epoxy.

Paul, thanks for the tips, the wing is already in the fuselage, guess I should have done it before I put it together. I use thinned finish cure epoxy, 1 part resin, 1 part hardener and 1 part acetone. It goes on like water and soaks in really well. Not much to take off. Did this with cowl as a test, after the first coat cured I put another coat on with a little less acetone and it came out like glass after sanding. But it was one piece without any overlaps and took quite a bit of sanding to get it smooth. No filler other than the fiberglass.

Forgot to mention, this is the way Tom Dixon finishes the whole airplane except he uses 5 minute epoxy and works fast. Claims it isn't any heavier than a filled silkspan finish. I was going to call him to get some tips but he doesn't put his phone number on his web site.

Paul Wood · « **Reply #4 on:** February 11, 2010, 07:51:37 AM »

Bob,
For future reference, Nelson's will stick to nitrate but not butyrate. I think he actually states that on the paint bottle. I've always had good results using water based MinWax polycrylic to apply the glass and use as a primer when mixed with talcum powder. I don't have any nitrate around so I've used the MinWax method for years. I apply it with a foam brush. Works well under Nelson's. I also spray the glass with hair spray before cutting to minimize the dreadful thread separation. Have fun.
Paul

Alan Buck · « **Reply #5 on:** February 11, 2010, 08:31:18 AM »

Tom Dixon uses 5min epoxy thinned with actone to a water like mixture. then after its dried puts on a second coat of the same mix. the actone gives a longer working time to brushing on the fiberglass. use a acid brush

Steve Fitton · « **Reply #6 on:** February 11, 2010, 09:08:47 AM »

I use Z Poxy finishing resin thinned 50/50 with methanol, brushed on. I only do one coat of epoxy which fills the weave of the .5 oz glass about half full, but this is a good thing, I find if I fully fill the weave with resin it is very hard to judge when you have sanded enough. Seams are no problem to knock down and blend, I often do a fuselage in four big pieces (including the vertical fin) and just rough cut a big mess of glass, then sand back the seams later on. Its great stuff!

Randy Powell · « **Reply #7 on:** February 11, 2010, 10:02:40 AM »

Back when Superpoxy was readily available, I used to finish fuselages with finishing resin and 1/2 ounce glass. You could get a really nice base that way. A little primer, sand and shoot Superpoxy colors. That was great stuff and made for a very light finish. Iron on plastic on the flying surfaces and let's go flying.

I suppose it could still be done with finishing resin, glass and KlassKote. But I haven't tried it.

Walter Hicks · « **Reply #8 on:** February 11, 2010, 08:00:45 PM »

I have used the 5 Min epoxy method, works great. Another one is simple and faster but more expensive. Bob Hunt did this years ago. .5 Glass cloth applied with Foam friendly CA, sand off , apply more if needed sand off , filled and ready for Nitrate dope , then primer and paint . Dries in seconds and very easy to sand . It is as light as resin and possibly easier to sand. I use it on all solid surfaces. I did an entire plane with it before. The downside is the cost.
The upside it is done NOW! And to me easier to sand than epoxy. I then use spray can auto primer , sand off it is now ready to paint!!!!! Use just like the epoxy sand until it is flat no shiney spots , fill the weave then sand. And I
can vouch for the weight not being excessive .

Kim Mortimore · « **Reply #9 on:** February 16, 2010, 12:52:29 PM »

Walter,

Was the glass cloth laid on first and then the CA to attach it wicked thru the cloth, or is it somehow possible to work fast enough to apply CA first and then lay down the glass?

Thanks,
Kim Mortimore

Paul Wood · « **Reply #10 on:** February 16, 2010, 07:02:50 PM »

Kim,
The glass is laid down and the CA is wicked thru the weave. It works well, but what you see is what you get. It sets instantly so any wrinkle or misalignment will be there until you sand it out. Speaking of sanding, it's very difficult to sand, but really not necessary before priming unless you need to correct a high spot or blemish. The fumes are very strong, so use a small fan to ventilate the work area.
Paul

Walter Hicks · « **Reply #11 on:** February 17, 2010, 09:19:42 PM »

Paul,

I use FOAM FRIENDLY ORDERLESS Ca, which takes longer to set and sands easily. I would not use regular Ca as it sets as you said very quickly and is too hard to sand.. The Foam friendly used in the thin works great, you lay the glass down as flat as you can get it and start in the middle and with your finger(use a rubber glove ) start working your way out to the edges. The stuff I use is called "Super Gold" 100% foam safe , Insta -cure oderless thin glue 5-10 second.

I believe Bob Smith Industries makes it for hobby shops. I get it from Hobbytown USA.Sanding is no problem it powders off.

Paul Wood · « **Reply #12 on:** February 18, 2010, 09:02:00 AM »

Walter,
Great idea! I've used Super Gold on foam, but never thought about using it on fiberglass. CA & glass is the method I use to reinforce ABS plastic and your method will certainly make it a lot easier. Thanks!
Paul

Douglas Ames · « **Reply #13 on:** February 24, 2010, 10:52:55 PM »

Bob,
I've used .5 oz. cloth and fin. resin in the past with good results. Seams were never a problem. Getting an even coat of resin is the trick. Not much too add except to mix your chemical soup well and use a stiff brush and dab problem spots.

Bob Reeves · « **Reply #14 on:** February 25, 2010, 12:20:43 AM »

Finally just started putting it on in pieces using the nelson paint right out of the bottle. Turned out better than I imagined and it's a tad easier to sand than epoxy. The fiberglass conformed almost too well as the grain shows right through. Going to try corn starch in Nelsons for a filler coat and see how it goes.

Pinecone · « **Reply #15 on:** March 04, 2010, 04:47:33 PM »

When I glass with .5 ounce cloth, I just overlap. It wil sand through pretty easily to remove bumps. Sometimes too easily.

For weight, the proper ratio of resin to glass cloth is 1 to 1. So 0.5 ounce per square yard, shoul dend up weighing 1 ounce per square yard.

I do similar to mentioned, put on epoxy (normally WEST), cloth and then if needed, touch up any dry areas. I hit the resin lightly with a cover heat gun, and blot out as much resin as I can with heavy duty paper towels. Not quite vacuum bagging, but you can get some very light finishes this way. The glass cloth and resin adds a lot of strength also.

Bob Reeves · « **Reply #16 on:** March 16, 2010, 07:38:32 AM »

This project is going slower than I like but this is the 4th airplane I've built this winter and running out of go-juce for building.

As said above I put the glass on with Nelsons straight out of the bottle. I then brushed on a second coat and sanded with 320 till it was pretty smooth. The fiberglass grain and wood grain was still very visible. I mixed up a batch of 1 part Nelson, one part water and one part corn starch. Brushed this on yesterday and started sanding this morning. This is going to work great as a filler, a little harder to sand than corn starch in clear dope but it seems to fill great. I have a couple seams and a little deep grain that will take extra filler but mostly it will sand out close to being ready for paint.

I was a little concerned about how corn starch would react being mixed in a water based paint but it seems to work really well. The big test will be when I pull the masking tape off after I get it painted..

Ward Van Duzer · « **Reply #17 on:** April 14, 2010, 07:29:49 AM »

FWIW

I was there when Hunt glassed his Crossfire rebuild. He sprayed a LITTLE Spray 77 adhesive in the air above the fuselage allowing the mist to drift down to the fuse. When the F/G was laid down it was a simple matter to lift and pull the covering to remove all wrinkles. Then applyed the CA. Yes, the man drives me crazy to watch him work!

Ward-O

Author Topic: Fiberglassing fuselage (Read 1761 times)

Bob Reeves

Fiberglassing fuselage

Allan Perret

Re: Fiberglassing fuselage

Paul Wood

Re: Fiberglassing fuselage

Bob Reeves

Re: Fiberglassing fuselage

Paul Wood

Re: Fiberglassing fuselage

Alan Buck

Re: Fiberglassing fuselage

Steve Fitton

Re: Fiberglassing fuselage

Randy Powell

Re: Fiberglassing fuselage

Walter Hicks

Re: Fiberglassing fuselage

Kim Mortimore

Re: Fiberglassing fuselage

Paul Wood

Re: Fiberglassing fuselage

Walter Hicks

Re: Fiberglassing fuselage

Paul Wood

Re: Fiberglassing fuselage

Douglas Ames

Re: Fiberglassing fuselage

Bob Reeves

Re: Fiberglassing fuselage

Pinecone

Re: Fiberglassing fuselage

Bob Reeves

Re: Fiberglassing fuselage

Ward Van Duzer

Re: Fiberglassing fuselage