diggs_74

So here I am with this really nice glassed balsa tail that I got from Dave N. for a Seeker I'm building for 428.... I would hate to put this really smooth and very rigid tail on a Ultra Coted fuse... So what I was thinking is that I would glass the fuse and paint it. This is something I've not really tried and I was wondering if anybody has any pointers for having this turn out on the first try.... Any tricks, tips or general info would be greatly appreciated.

Thanks All.

HighPlains

My Feedback: (1)

What resin system are you going to use? I use polyester with 3/4 oz glass cloth.

I think that polyester is more rigid than most epoxies, though it smells like hell.

So that is the first thing for you to decide.

DHG

My Feedback: (7)

Lee,

Use the lightest cloth you can find -- Aerospace Composites sells a 0.6 oz. grade -- and apply it using Minwax Polycrylic acrylic urethane wood finish, thinned slightly with water and smoothed on with a good-quality brush. Don't use too much of the Minwax at a time, and let the first coat dry thoroughly. Sand lightly with #400, then apply a second coat, this time filled a bit with cornstarch or baby powder. Sand again and it should be as smooth as a baby's tushie. (Smells similar, too.)

Mr. Medicated

js3

My Feedback: (3)

Lee,

Take your finishing cloth and cut it oversize for each side and top and bottom of the fuse. Let's see... You'll need a left and right side, a fuse bottom piece, a fuse top/back piece, and a fuse front/tank compartment cover piece.

Take all these pieces and spread them out on individual pieces of wax paper. Lightly mist the pieces with 3m 77 spray and I mean LIGHTLY--just a quick press and release of the button. Now carefully stick the cloth to your fuse using the wax paper to handle the sticky pieces. Pull away the wax paper and trim the glass as necessary. Mix up One ounce of Z Poxy finishing resin. This should be way more than enough but it's better to have too much than too little. "Paint" your fuse with the epoxy resin to completely wet out the cloth. Using a Sig or Bondo squeegee (or a credit card) remove as much of the resin as you possibly can. Once you've removed all of the resin that you can, go over the whole thing again with the squeegee and remove some more resin. You will be able to remove more resin. Now use TP or paper towels to blot even more resin from the glass cloth. After the Z Poxy has dried, lightly sand with 320 wet or dry paper and remove any excess cloth from the edges. Wipe away the sanding dust with a paper towel and alcohol. Some people like to put on a second coat of resin to fill the weave, some people like to primer at this point. The last time I did this, I mixed talc with Mixwax Polycrylic and used this as my "primer". It worked well. Wait for this coat to dry then sand again with 320 paper. Now it should be ready for paint.

My only complaint about using talc to mix with the primer was that my plane and workshop smelled like a nursery for about two weeks. Not the way a workshop should smell. Better the smell of acetone and lacquer thinner.

diggs_74

Thanks for all the good advice.... I'm not quite ready to start yet but will be by this time next week. I've got some very fine (like talc) micro baloon stuff, can I use that instead of the talc for the last coat?

js3

My Feedback: (3)

Lee,

I've never tried micro balloons for the primer stage. They may work ok. I do know that they are very much more expensive than talc or corn starch.

diggs_74

That's a good point John.... I was just wondering if it would work since I already have them.

daven

My Feedback: (1)

Lee,

Using the 3m will allow you to do more than 1 side at a time. I use a 3m spray called something like repositionable spray mount adhesive. This spray is not nearly as agressive as the 3m77, but still stong enough to hold everything in place. I've struggled trying to use the 3m77 with the light glass (although I have not tried it on wax paper per Johns recommendatiion). When he says lightly, he means it.

Using the spray really helps with the light cloth, keeps it smooth and is much easier to wet out faster. I usually will do one side a night on 4 consecutive evenings. Before starting a new side, I sand the edges smooth. I think I can get a better surface doing each side individually, rather than trying to do it all at once, but thats me.

Definately test it on a small piece before trying a complete fuse side. I've used both the Water Based Poly's and epoxy, and prefer the strength and hardness of the epoxy. After you get the glass down with epoxy, you can use the water based poly to fill the weave. You can mix it with microballoons to save weight.

I've never tried the Polyester, I've always been told it smells terrible so I have never used it.

splatt

the "theys" of the world say breathing sanded micro-ballons is bad, bad, bad.

diggs_74

What do "they" know anyway Breathing any type of glass dust isn't good for you that's for sure... However, if you are wet sanding it's a mute point.

CafeenMan

Fiberglassing isn't difficult at all. I've done several all glassed models and many more that only the fuselage was glassed to make it more fuel proof than plastic coverings. I don't use home-brew fillers. I just use epoxy primer and it does a great job and it's already made. Mix, thin and spray.

[link=http://airfieldmodels.com/information_source/how_to_articles_for_model_builders/construction/apply_fiberglass_finish/index.htm]How to Apply Fiberglass Cloth[/link]

HighPlains

My Feedback: (1)

I think the polyester is easiest all. I also think that is gives the hardest surface, But I would really like to see an experiment to find out which method is stiffer, and provides a harder surface.

As far as putting on the glass, just cut it slightly oversize and lay it on the bottom of the fuselage. Lightly smoothed out across the balsa with the back of your hand. Static cling will hold it in place, no need to use contact spray on it I mix up the polyester with about 12-15 drops to an oz. though I only need about 1/3 oz at a time. Just pour a small pool of resin onto the surface with the glass a few inches from one end. I just spread it out was an old credit card as thin as it will spread. About an hour later, just sand off the excess glass over the edges with 320 paper dry. Do another side and repeat until completely covered.

At this time, you will see the weave of the cloth, so I apply another layer of resin over the entire fuselage and let it set for a few hours. Then you can lightly wet sand with the 320 paper and a 3M sanding block. At this point, you can prime sand, prime and paint. Or if you are more lazy like me, just wax the surface and go fly. Or shoot a clear over it. Many options.

On a wing or tail feathers, I might go to a third coat of resin after sanding the second. Just depends on the type of surface finish you are looking for. But the key to wet sanding is to use lots of circular sanding strokes with the block. Low spots are shiny. Lots of 320 paper, always wet, and lots of paper towels. Work wet, and no dust.

DHG

My Feedback: (7)

Bob,

The hurricane blast from the Lycoming 0-300 purring away on the stand in the corner of your workshop to vent the polyester fumes out of there may make the glass cloth a little hard to handle ... otherwise, that's a good method.

I like the Minwax because it's quick and easy and doesn't stink. But I must admit, if you get too much on there, the water content will raise the grain of the wood. Choose your poison, I guess. [:-]

PylonWorld

The water based polyurethanes are great as primer when mixed with white microballoons (aka Q-spheres or quartz spheres).

Although the MINWAX Water-Based Polycrylic looks like it is WBP, it actually is not. When I was doing some fact checking on it, I found out that it has components that keep it from being a true urethane. I did some testing on foam and wood sheets to test the strength of various materials and the Polycrylic is not as strong as OLYMPIC Interior Water Based Polyurethane. Varathane Diamond Wood Floor Finish is also good, but you have to buy a whole gallon from any source I tried. The Olympic is about $8 a quart at Lowes.

For attaching cloth to wood without grain or warping problems, I have used the Minwax Fast-Drying Polyurethane in the gold or silver can. Cleanup is not as easy and ventilation is a must.

I keep some Olympic WPB mixed up with white microballoons all the time. It is a great fast filler. You do have to stir it everytime you use it because of separation. Talc probably doesn't have that problem. I need to try it since it smells so nice.

diggs_74

All this info and only one plane to try it on The wing for this plane I just finished with Oz Cover and will be painting sometime this week... If that turns out ok then I may entertain doing the fuse in the Oz Cover and paint also.... So many decisions.....

luv to race

My Feedback: (1)

3/4 oz cloth and squeegee on Z-poxy "finishing resin"... sand with some 400, then paint with clear. simple.

daven

My Feedback: (1)

yeah Randy, its simple when your Dad does them

diggs_74

I see, now the truth comes out.... It's always simple when someone esle does it

HighPlains

My Feedback: (1)

Here is an independent authority on building light. Perhaps one of the best builders in the world, Dave Platt. What does he use with fiberglass cloth?

Sig Polyester resin.

Read this one page article:

http://airfieldmodels.com/masters/in...latt/index.htm

The airfieldmodels web site is interesting to look at. Lots of info, a little bit anal, but good source of techniques.

garys

Actually Bob, if you read the "applying fiberglass cloth" how to article on his site, he uses Epoxy Finishing Resin........apparently EZ Lam from Aerospace Composites.

http://airfieldmodels.com/informatio...nish/index.htm

GS

HighPlains

My Feedback: (1)

Yes, but the one you refer to is not Dave Platt. Platt said epoxies work, but weigh more. It's towards the end of the Platt interview on building light.

garys

Ok, missed that one. I just went to the how to articles. He's an incredible scale builder, but I've watched him snap a couple nice airplanes into toothpicks on takeoff and landing!

diggs_74

Well, after glassing one side of the tail saddle area, this glassing stuff is for the birds.. After seeing how well my oz covered wing turned out I have a hard time convincing myself to use the glass... I will glass the other side of the saddle area but other than that I'm going with the Oz cover... Thanks to all for the info.