GWS Beaver Builders Information

The Following is an outline of a modified build I completed using the GWS Beaver fuselage and tail feathers along with a modified HobbyZone Super Cub wing. The fuselage and wing were glassed using 1/2 oz fibreglass cloth and Minwax polyacrylic.

parts used in this build are:
-1. GWS DHC-2 Beaver Slope Glider kit #GW/DHC2-SG or NPS (No power system)aver kit #GWAEO016
-1. HobbyZone Super Cub wing #HBZ7120
-2. Pico servos
-1. Castle Creations Pixie 20 speed control
-1 Eflite Park 370 brushless inrunner
-1 GWS or Eflite Gearbox for above with "C" gearing
-1. GW/R4PII receiver
-2. Dubro ez conectors ( for the servos )
-2. Hangar 9 2.75" Prolite wheels
-1. Dubro 1" foam tail wheel #DUB100TW
-1 Piece of K&S aluminum streamlined tubing 3/8" or 1/2"
-4 Great Planes 2-56 clevises or you may use the stock GWS ones
-1 Foam meat tray or other source of foam to fill the battery compartment

Building material:
Hobby knife and blades
Zona saw with long flat blade (optional)
gws contact cement
CA (cyanoacrylate Adhesive)
pair of metal cutters suitable for cutting piano wire
Minwax Polycrylic wood finish (must be the waterborne variety)
1/2 or 3/4 oz. fiberglass cloth
3M Blenderm Tape
Isopropyl alcohol to clean ALL foam parts prior to gluing
Light weight spackling compound generally used for drywall repairs
Various grits of sandpaper up to 600 grit
Dremel Moto tool may come in handy if you have one
Optional: pinvise and some small numbered drill bits make things go more smoothly

The First step is to cut or drill the slot in the top left side of the fuselage for the rudder control rod . The instructions are not very clear on this point but if you look very carefully you should be able to see a small dimple where the hole should be.

Then cut or drill a slot on the rear right side of the fuselage for the elevator control rod.

Next step would be to glue in the motor stick however I generally do this last. Either way be sure to refer to the page on thrust angle before gluing in the stick to assure you have both right and down thrust correctly dialed in.

I dont use the battery compartment so now is the time to cut a plug from some scrap foam or an old meat tray and shape it to fit in the hole. I used ProBond polyurethane glue to adhere the cover... NOTE OF CAUTION! Probond expands so you must tape or clamp the foam in place to stop glue from oozing everywhere as it cures!

Here is the cover glued in place. Note the hole just in front of the landing gear slot... that will be our next project.

Once you cut off the cheeks you will need to sand to blend in the curve leading to the cowl area. Reviewing images of the prototype can be very helpful at this stage.

To Fill in the hole left when we cut the Beaver's "cheeks" off I used more of the Probond and mixed it with a few drops of water. I then loaded the hole with this mixture and immediately covered the hole with packaging tape and set a heavy glass lid on the tape to keep it from ballooning out as the glue cured

The other obvious problem with the GWS Beaver is the area of the nose directly in front of the wind screen. I simply cut straight down with my razor saw along the line of the wind screen and rounded the top of the nose to match. You can see the portion I removed by looking at the stock fuse of the yellow plane versus the modified nose of the white fuselage.

I used a steel straight edge and a fresh blade in my hobby knife to make the cut. IMPORTANT: dont throw out the off-cuts as we will use them in the next step.

As noted earlier on, I am using a Hobbyzone Super Cub wing for a more scale looking wingspan . The Hobbyzone wing is just shy of 4' which makes it nearly the perfect size for the GWS Beaver. Because the Cub wing has a flat bottom I had to cut the wing saddle from the Beaver fuse. Simply draw a straight line with a sharpie from the front of the existing saddle to the rear.

Now here is where that off-cut comes in: you can see from the picture that the new saddle is very thin in the center... but that off cut makes a perfect reinforcement filler for this area.

Here you can see the off cut glued in place. I glued it in with white glue and held it in place with packaging tape while the glue set however probond or gorilla glue would work just as well.

I ran into a minor issue at this point in that the new saddle appeared to be too large for the wing so there was a gap at the LE or TE depending on whether the wing was pushed all the way forward or aft.....

Solution: I cut about another 1/8 inch deeper into the fuselage so the wing nestles farther down into the fuse (note how the new cut curves up at the LE to fit snuggly against the curve on the wing. Be careful here as cutting too much from the front or the rear may play havoc with your wing incidence and flight characteristics.

The final result looks much better as the wing appears to be part of the plane rather than looking like it is sitting on top of the fuselage. Now is the time to do any final filling with the light weight drywall spackle and sand it all smooth..

The GWS Beaver has a few un-beaverlike flaws; one is the incorrect door outlines so I filled all of the doors with lightweight spackling and sanded... and filled and sanded....and... well you get the picture. Another major issue are the "cheeks" on the lower portion of the fuselage. Here you can see the cut I made using my Zona razor saw. I simply drew a straight line with a sharpie and started cutting

As a final finishing step I decided to cover my fuse with fibreglass. Glassing is not critical or necessary but it will greatly improve the strength of your model and will cure hangar rash (dents and divots in the foam from handling and traveling to and from the field). I have used both 3/4 oz and 1/2 oz fibreglass cloth with success and other than a tiny difference in weight I don't find one any better than the other. I use Minwax Polyacrylic wood finish as my "resin" to adhere the glass cloth, as it is inexpensive, water clean up and doesn't eat the foam.... which is obviously an important consideration.

Because the Beaver tapers along its length on all 4 sides I have found it's easiest to glass one side at a time starting with the bottom. I generally cut a piece of the cloth to size with about 1/2-1" extra on all dimensions, which can be easily cut off after the PA (Poly acrylic) is applied. Using a 2" disposable foam brush start in the center and work out towards the edges. I generally only apply the PA right up to the point where fuselage starts to curve around to the next side and then trim it neatly with sharp scissors before completing the application of PA over the curve. Once this is completed on one side I leave the fuse to dry overnight before moving to the next step.

Once the PA has cured completely its time to lightly sand the edges of the glass you applied yesterday using 600 grit paper and being VERY gentle so there will be no visible transition to the new fibreglass that we are adding to the sides today. You may see some slight fraying along the edge of the fibreglass but not to worry this will be taken care of with additional coats of PA. I now repeat the glassing steps used on the bottom to apply glass to one side of the fuse and again leave it over night to dry. Next repeat the sanding step to feather the new glass so there will be a smooth lump free transition to the other glassed areas. Continue these steps on the other side of the fuse and finally the top... don't forget to do the windscreen and nose area when you do the top of the fuselage. Once this is done give everything a light sand with 600 grit paper and then give the whole plane another coat of PA. I usually do 3 coats of PA with a light sanding between each coat to completely fill the weave of the fibreglass cloth and make a nice smooth surface.

Now its time to prepare the wing for fibreglass. The Supercub wing's chord is actually too broad so I had previously cut about 1/4" off of the trailing edge of the wing along the entire length. I also removed the plastic wing reinforcements, as they are only really necessary if you plan on holding the wing on with elastic bands, which I don't. The foam of the Cub wing is very porous and doesn't sand well but after filling with light weight spackle it gets easier. I think it may be a good idea to coat the wing with PA prior to sanding but cant confirm if this will help.

You will notice there are dimples on the surface of the wing. I opted to glass over these and lightly sand the glass afterwards to smooth these dimples out. I pre-installed the wing strut mounts in the wing before glassing but could just as easily have installed them after glass was applied. I use the same basic process to fibreglass the wing doing one side at a time and trimming the extra. You may find that the fibreglass doesn't adhere well to the leading and trailing edges of the wing; this can sometimes be sorted out with a light touch of a covering iron on low heat however you must take care not to melt the foam!

Continued on page 2>>

Use the GWS contact cement
(the glue in the white tube in your kit) to glue the fuselage together. Apply a thin layer on both halves of the fuse then press them together and immediately pull them apart. Let the 2 halves dry for about 10-15 minutes then careful press the 2 halves together (note alignment is important as you wont get a second chance here)