Boss248

I want to use 3/4 oz. cloth on a fuse that is solid balsa(no bays) and I remember reading somewhere in RCU where someone used something other than finishing epoxy. I seem to recall they used water based acrylic polyurethane from a can and brushed it on.
I want something that is easy to apply with no or little sanding needed after the cloth/resin has set up. Also I have been trying some different spray paints that I can buy locally but I keep seeing Rusto-leum's name pop up. Can someone that knows FOR SURE please tell me what paint they have found that is fuel proof. I know I can go the PPG route but I have to buy a pint at a time @ $30.00 a pint. I guess I can do the base painting with Rust-oleum or Krylon and get a pint of PPG clear which the paint shop can load into spray cans but I am open to other ideas.

Thanks
Boss

barto

Cafeen is the man to answer your questions
This is his site www.airfieldmodels.com

KidVermin

My Feedback: (3)

All the epoxy enamels are fuel proof and I've used Krylon lacquers too.
I'm not a fan of the Rustoleum since it is oil based and it's best to stay with their top colors.

Azcat59

One of the easiest ways to stick the light glass to your fuselage is nitrate airplane dope. Sig sells it, and there are other sources. Two coats on the raw wood, few hours apart, light sanding, drape the cloth over part of the fuselage, and apply the dope on top the cloth. It will soak right on through. Give it several coats of dope, very little sanding required, preferably no more than two coats a day. Then give the whole thing three days to chemically cure before you put anything else on.

Follow it up with the grey Rustoleum primer out of the spray can. It sands easily, and is fuel proof. I even use it for the grey color on the bottom of WW II warbirds, but spray on a light coat of Varathane satin finish poly-U to harden the primer slightly and protect any ink lines.

The Rustoleum colors in the spray cans are likewise fuel proof, at least with 10-15% nitro fuel, but I wouldn't pour raw fuel on them and leave it.

Clair
AMA 15654

FHHuber

You want to avoid the epoxy and/or poly resin... and still want a strengthening layer of cloth to aid in smoothing the aricraft... how about [8D] silk and yellow glue [8D]

Easy to sand.
LIGHT.
strong.
Inexpensive!

And you mix some yellow glue with talc and water for a fillercoat before your first fuelproofing/coloring coats, for a cheap, easy to sand light filler.

(based on tricks used in the 1930's using white glue. Yellow glue is superior to white for just about everything.)

The use of Nitrate Dope... similar, but more expensive. And you have to deal with the toxic base of the Dope. (which is flamable and smells like nail polish remover) And Dope NEVER stops cureing and never stops shrinking. Yellow glue stops shrinking in 24 hrs. any paint other than a laquer over Dope will eventually crack.

Boss248

Does anyone else have any ideas or know about the use of water based poly urethane to go over 3/4 oz. cloth???????

Thanks for all the suggestions guys....

CafeenMan

Why does it have to be water-based polyurethane? No matter what you use to apply the cloth, you're going to have to do the same amount of sanding after it dries. There actually isn't much sanding to do if you put the resin or poly on properly.

Boss248

Cafeenman...don't get me wrong...I have always used the method you described but I am only looking for an alternative. I have used the dope method and the white glue method all with success but I want to stay open to other ideas.

grahamd1

My Feedback: (1)

I think the product your thinking of is Minwax, here in the UK it is no longer available (European rules), so a UK company mixed up an alternative, and added some extras. However its almost the same stuff.

Heres a link to a short article on how to apply it.

http://www.rcworld.co.uk/polyc.htm

I've been using the stuff for almost a year now on several differnt types of model, from all foam to scale WWII warbirds, and would need to be forced to go back to Epoxy. For smaller models (<70") I have now switched to using Tissue paper (shoes come wrapped in the stuff), as this only requires about 3~4 coats, and sanding can be done in minutes with little effort to achieve a very hard smooth finish.

Boss248

Thanks Graham...that is the info I was looking for.
Ha ...the 3Styla is not looking to bad either. I have not seen it in ads here in the USA but I guess there are hundreds like it all over the globe.

grahamd1

My Feedback: (1)

Your welcome, the tail in the pictures is from my BF-109.

ZeppelinIII

I have done a couple of models using water-based polyurethane to put down 0.5 oz cloth (0.75 is basically the same)...to answer one question, the reason to use a water-based poly is for clean up, you can just rinse out your brush with water. As to the process, my opinion as too the best approach is to put on a light coat to get the glass down, and it'll take a few different pieces, so do all of them first with a single coat, then add a second light coat once the entire fuse/stab/wing/etc. (whatever you're working on) is done, then add a final coat of polyurethane mixed with corn starch....I prefer to add a heavier coat of that, and then sand more (to help even everything out, but if you put a very light coat of that on you could probably get away with very little sanding....

pic is best example I could find off hand, using that approach on the fuse of a sig Kavelier...

Boss248

Zepp...what do you use for the final color???....I did a test piece and it looks like it will work well but I was wondering about the Corn Starch...is that working as a filler to make sanding and filling of the grain.
I need to know what people are using as a final color or clear coat that is really fuel proof.

3dd

My Feedback: (6)

the only problem with water based products is the real chance that it will warp balsa planking even after it is glued down.solvent based sanding sealers will work better and will not warp anything.they do stink but the finished plane will be lite and have a good finish

Boss248

You have a point...I did notice a warp because I was painting it over 1/16 sheeting.

Azcat59

See my earlier post, using nitrate dope and silkspan on the wing and tail surfaces, and nitrate and glass cloth on the fuselage. Will see if I can get the pic of my TF P-39 to post. Three years old, weighs 8 lbs. and 8 oz. Formula U polyurethane olive drab, Rustoleum gray primer on the bottom, followed by a thin coat of Varathane satin finish poly-u over the gray.

Clair

Boss248

Very nice indeed Clair...I have used the doping method in the past and it always worked real well. How does the P-39 fly???it looks like a very clean plane aerodynamically...I bet it flys like a pattern plane. Also what motor is in it??

jnaarnold

My Feedback: (4)

It doesn't get very hard, and is still flexible. I used it over blue foam however. The next thing I am trying is 'Modge Podge'. my wife uses it on craft stuff and it is tough as nails. I have a few coats drying tonight and should know something more in the morning.

ZeppelinIII

Boss,

- That was using TF Lusterkote paint and clear coat finish...It claims to be: fuelproof (up to 15% raw nitro, any spent fuel)....and I haven't had any problems at all yet with 10% nitro....I have to agree with other opinions on here that the spray cans aren't the greatest, but they work for me for now...

- I agree that the waterbased will warp the balsa if applied to heavily, but a couple of light coats doesn't seem to have been too bad...you can still use an oil based poly, it just makes clean up a little more difficult

- yes, the Corn starch is basically a "fairly" easy to sand filler (also easy on the lungs if that is a consideration) that fills the weave of your cloth, and helps fill any other small dimples/holes/low spots

Azcat59

The P-39 is a real ***** cat.....with the trike gear ground handling is simple, and the airplane lands well with or without the flaps. No ballooning when the flaps are down. I have one of my old pattern engines in it, an OS 61 FSR ABC, with a Perry Pump so I could put the tank under the cockpit and minimize any problems from the long nose. I used very little of the plastic cowl, and built most of the front end out of balsa so that I could get the smooth lines from canopy to spinner that the full scale plane had, rather than a sharp "break" at the firewall area.

Clair

jmupilot

I just t finished glassing a Royal Cessna 336 Skymaster 76 in wingspan. I am using the Minwax Poly U water based finish. I am using .75oz glass, and apply it by brushing a light coat thru the glass. I use a 1 in foam brush to apply the poly-u. After that drys, I apply another coat. Then sand lightly with 320 grit paper. then apply another coat of poly-u. I sand again lightly and then spray sandable primer on. This fills any left over weave the poly-u didnt fill. I have also mixed micro-ballons in one can of poly and that does a fine filling job too. After the primer the color coats are applied. This method was given me by a fellow club member that build models professionly for a living. So far the Skymaster wieghs in at 7.5 lbs with everything in it but the radio gear.. I'll try to get pictures posted as soon as i can.

Pete

kdheath

Another filler that works well with Minwax PC is zinc stearate. Available from Randy Smith at:

http://www.aeroproduct.net/

Mix 2 parts PC, one part denatured alcohol, one part ZS. Sands easily, makes a nice nick filler mixed with PC. Also works well over carbon fiber veil or silkspan..

Eagle Flyer

My Feedback: (84)

Will the Minnwax polyurathane stuff work on foam or will it eat it? I am looking for an easy alternative for glassing a foam plane. Thanks

kdheath

Minwax Polycrylic is acrylic, not urethane. It is not fuel proof (I think I heard that alcohol dissolves it but haven't tested it yet) and it won't harm foam. It's water based.

CafeenMan

Minwax polyurethane is fuel-proof. I've used it as the sole finish on several planes and a set of floats. I don't know about polycrylic.