There are lots of methods to use fiberglass fabric to a construction. The commonest strategies use both polyester or epoxy resin and catalysts. Among the resins require unequal combine ratios, like one half epoxy to 2 components hardener, which is troublesome to measure precisely. I additionally dislike polyester resin as a result of it actually smells foul. For all these causes, I exploit Pacer Expertise’s Z-Poxy Ending Resin (#PT40). It’s an equal-mix product that has little to no odor and is straightforward to work with. Remedy time to a cheesy consistency is about 30 to 45 minutes. After about two hours you may deal with it, and after 4 to 5 hours, you may sand it or apply one other coat. Even in case you have by no means finished this earlier than, it’s very easy to do.
LET’S GET STARTED
Some objects you will have are paper towels, 1-inch hardware-store chip brushes, one thing stiff to make use of as a “squeegee” (a bank card works nice, as do plastic-coated taking part in playing cards), a passion knife with no. 11 blades, Z-Poxy Ending Resin, and a few denatured alcohol. A flat floor, like an outdated desk or workbench, coated with newsprint or another disposable masking is great for setting components on. Additionally, you will want some 100- and 220-grit sandpaper to clean out your prep work. A rubber sanding block, accessible at most {hardware} shops, will assist enormously. Oh sure, and a few 5-oz. disposable ingesting cups shall be helpful for mixing the resin.
Remember that different-weight fiberglass cloths (from 3/4 to three oz.) work in a different way. The heavier the fabric, the extra cussed it might be to put down correctly—be affected person.
Whether or not it’s a one-piece or a two-piece wing, faux that it’s divided into 4 quadrants: high left, high proper, backside left, and backside proper. It doesn’t make a distinction which part you begin with. When you have removable ailerons and flaps, take away them and do them individually. Now, let’s get all the way down to enterprise.
PREPARATION
Earlier than you begin the primary panel, make it possible for the entire wing has been finish-sanded with 220-grit sandpaper after which vacuumed clear. Do the opposite three panels in the identical method. In case your balsa wing has any dents in it, spray the dented space with a bit of water and gently rub it into the dent. Let the world dry out; the wooden grain will raise barely, inflicting the dent to fade like magic! The final thought right here is to have clean, flat, ding-free surfaces over which to put your fiberglass fabric.
So far as fiberglass fabric goes, my fundamental information to what weight to make use of is instantly associated to airplane measurement. For fashions with wingspans within the 80-inch vary, you should utilize something from 3/4- to 1 1/2-oz. fabric. Something 100 inches and over, I exploit 2- to 3-oz. fabric. You get the concept. To search out the place to purchase your glass fabric, verify passion retailers or giant distributors. You may as well store round your native boat/marine {hardware} shops for the fabric you want.
Now, measure your wing panels and permit at the least an inch of waste materials all the best way round. After chopping your first piece of fabric, lay it on high of the wing panel and rub your hand over it to make it possible for there may be nothing below it, as any speck of sanding mud will break the end.
THE GLASS ACT
For the primary coat of resin, I add about 5 to 10 p.c alcohol to the resin. This isn’t actually really helpful by the producer due to the variances of alcohol used, nevertheless it helps the fabric lie down simpler with out pulling it out of form whereas making use of the resin. While you apply the second coat of resin, nonetheless, use it full energy. Combine the resin components collectively fully, add the alcohol, and blend once more till the alcohol is absolutely built-in.
Lay the fabric down over the naked balsa, being certain that it lies down fully clean. Pour a small line of the blended resin down the middle of the wing panel spanwise, and unfold it out from the middle to the main or trailing edge—it doesn’t matter which—then do the remainder. Preserve a disposable ingesting cup useful to squeegee off extra resin out of your credit score or taking part in card. Paper towels are good to have round, too, in addition to a 1-inch chip brush to brush down the perimeters and areas that you simply missed.
Now, spend a while going over these areas; fixing it now makes life quite a bit simpler in a while. By this time, your arms will really feel as if you happen to simply dealt with a big ball of cotton sweet—good and sticky. Wipe your self and any instruments you want to preserve clear utilizing a paper towel and a few alcohol. Belief me—after you have accomplished the primary panel, you can find the opposite three will go a lot sooner.
I often do the top-left panel adopted by the top-right panel after which let treatment. I trim the perimeters with a no. 11 passion blade after which calmly sand the perimeters all the best way round. I flip the wing panels over and apply fabric to the opposite aspect. Don’t construct up an excessive amount of resin close to any edges as a result of, when it cures, you’ll simply have extra resin to sand off.
After you’ve finished all 4 panels and so they’re all absolutely cured, revisit the primary panel and really calmly sand and repair any little imperfections or dings that you simply might need picked up. When you have any wrinkles, bubbles, or brush hairs, now could be the time to sand them away. When you should sand down to this point by means of the fabric and resin that it leaves a naked spot, don’t fear. You possibly can lower a small piece of fabric and put it down with the second coat of resin, or if it’s sufficiently small (like the scale of 1 / 4), simply ignore it and put down the second coat of resin instantly over the naked wooden. Go over the opposite three panels and do the identical factor.
As for the wingtips, I merely trim near the wing, apply resin, let treatment, after which sand. If wanted, I’ll add scrap fabric to cowl any naked spots. When you have got all 4 panels finished with two coats of resin and they’re absolutely cured, use the sanding block to sand the wing clean. You’ll discover that the second coat of resin has cured pretty shiny. It’s because it simply lies on high and doesn’t take in in any respect into the wooden or the glass fabric. Use 100-grit sandpaper over the shiny surfaces to “break” the shine, then swap over to a finer-grit sandpaper, like 220, to finish-sand the entire panel. Do not forget that if you sand the fabric, watch out to not undergo to reveal wooden. The distinction now between a great wing floor and an impressive one is how a lot time you spend sanding the wing.
When you have got the whole wing completed as talked about above, you’re nearly finished. For me, the subsequent half is the ultimate step. Discover a well-ventilated space, and get some Rust-Oleum Automotive grey primer (a mean rattle can will cowl about 4 sq. toes) and calmly spray the wing panels. The primer will expose any flaws left in your fiberglass surfaces. Fill any pinholes or dings utilizing a lacquer spot putty or Bondo, let dry, and sand and primer once more.
Now you’re prepared to color your wing! Irrespective of the way you select to complete it, the sleek fiberglass will improve your mannequin’s general look.
WHAT YOU’LL NEED
Right here’s what you’ll want for this mission. The parts proven listed here are wanted to begin the mission. The strategy I exploit will work with any resin, whether or not it’s polyester or epoxy based mostly; I selected this Z-Poxy product as a result of I get pleasure from its working traits. Your scissors should be sharp. I exploit denatured alcohol for thinning or cleansing up the instruments, however rubbing alcohol may even work.
I lower the fabric a bit of oversize, lay it over the floor, and dry-brush any wrinkles out. I pour the blended Z-Poxy down the middle, from root to tip (as proven), and put together to “squeegee” the resin by means of the fabric.
Utilizing a clear bank card or plastic spreader, I unfold the resin towards the main and trailing edges, to a degree the place there aren’t any ridges of resin seen.
After fully spreading the resin, that is what the floor will appear to be. When the resin has cured, the surplus fiberglass fabric will be simply trimmed utilizing a single-edge razor blade or calmly sanded utilizing a sanding block. Right here, the wax paper protects the flaps from the resin, however the flaps are in solely to make it possible for the trailing edge cured straight; usually, I might take the flaps out.
Discover how neat and clear the surfaces seem after sanding the second coat of resin. All surfaces are actually prepared for primer. As a result of the second coat of resin doesn’t seep into the wooden grain, it varieties a crisp topcoat layer, which could be very shiny. Sanding it till uninteresting is suitable.
A small vibrating sander will be useful in breaking down the shiny topcoat of resin. The extra strain you apply, the sooner it really works. However watch out to not apply an excessive amount of strain on the corners—it’s possible you’ll undergo your fabric!
The fiberglassed and sanded wing panels for the large Hellcat I’m engaged on are nearly prepared for primer, as quickly as I finish-sand the inboard edges of the panels.
The identical fundamental method is finished for all management surfaces, as proven right here. The components are put aside till the resin cures, then the surplus fabric is trimmed away and sanded clean utilizing sandpaper.
For energy, I all the time glass the wheel-well interiors.
By Denny Deweese
