Rubber Band Catapult Gliders

[mbauer]

During 2019 I started a new way of designing some catapult Gliders. Thought small "profile" type gliders would be easy to fly.

Some did all right, most did not. Tried doing different things with the design to get good flyers using a simple rubber band launch system using a 1/4" wood dowel.

I made several gliders like this. A few were made and have survived. Below are some of the photos, taken today, to show a small sample of the designs.

For instance the F-4 Phantom has 8-different paints, only two survived sort of.

Since the original designs were completed, been thinking of ways to improve them to get better flights from them.

Most are "Lawn Darts", not real flight. The cardstock (110# Index [198.9gsm] used was too heavy.

Been using 65# [165gsm]Cover Cardstock for my big rockets. This cardstock will lower final weight of these models.

Recently, a new member: ReynoldsSlumber, has been posting about his attempts to fly scale paper models.

Since 2019 some of my thoughts have been constantly returning to these profile models that don't fly so well.

As you can see in the photos, the fuselage have warped over time. The glued back to back profile of the wings and fuselage have all warped to a degree.

The great thing about using Cover cardstock is you can find the same brightness rating for 20lb bond paper. This makes it possible to print hopefully on two types of paper and get the same look.

Underside of the wings can now be lighter weight bond paper.

The next thought was to widen the fuselage to 1/4" thick, instead of cardstock glued back to back. This should stop the warping and give a much stronger model.

One of the things I did was to make a small hook under the nose to be able to use a rubber band stick launcher. I added several layers of cardstock to strengthen this hook as well a balance weight for the models.

This semi-worked.

Today I started the re-design process to update the models to these new changes.

I have several models already complete as the Profile models, these will be updated to the thicker fuselage using the lighter weight cardstock/bond paper.

All of these "profile" type gliders are not drawn to scale, smaller rudders, increased wing span to remove weight and enlarge flying surfaces.

Here is a list of the models done so far as profile models before the new changes, each model has different "paints":
2023 List.JPG

The F4 Phantom has 6-different paints for instance, two are shown in the next photo. Blue Angle and Spirit of '76.

Here are some of the models that have survived the best since first test flights:
PICT0298.JPG

A close up of the very small hooks added:
PICT0301.JPG

Close up of the layered cardstock to add balance weight and support the hooks:
PICT0303.JPG

Updates will soon be added as I try different things to loose weight and the thicker fuselages for strength.

Mike

[mbauer]

Updated the first of the profile Gliders: The Playboy Bunny version.

Fuselage is 1/4" wide. This might allow bond paper for the model. I printed an updated version using 90lb Index cardstock and 20lb bond paper.

The first build had several issues that have been fixed.

Here are a couple of photos of the updated profile glider. Takes 2.5 hours to cut, fold and glue:
PICT0305.JPG

PICT0308.JPG

To save time and glue weight, I combined all of the fuselage pieces into a single part. It has been printed and going to build the first version today. Here is a screen shot of the fuselage. When I print PDF files from AutoCAD they show lots of white lines-they disappear when PDF is printed:
F4 Phantom Play Boy Bunny Paint Fuselage.JPG

The prototype above was done as single fuselage parts and some parts needed fixing.

I have several F4 Phantom paints that will be modified. Initial glide tests are very promising although the completed model has some issues with wing/horizontal stabilizer alignment.

Will be uploading a F4 Phantom model to the download section later today, not sure which one yet, minimum part count only two pages...

Mike

[mbauer]

3-More things found to fix. Will make make model easier to build before uploading.
1. Need Dash Fold Line on Horizontal Stabilizer/Elevator
2. Add some cut lines (dots) to Canopy
3. Need a couple of glue tab cuts to make the curve easier to glue on fuselage nose top & bottom

Photos taken during construction=Build Thread
Verifying Scale of PDF after printing: Make sure to print at 100% NO-Scaling
PICT0386.JPG

311-Fuselage piece is cut out
PICT0311.JPG

Closeup of Fuselage showing multiple cut locations, glue tabs cut lines (Dot Lines) & Fold Line (Dash Lines)
PICT0314.JPG

Time to do some edge coloring
PICT0319.JPG

1/16" wide Glue tabs, also shown edge colored fold lines, white dotted lines for the Wings, Elevator, Rudder-Don't cut these out yet, wait until the fuselage is complete
PICT0322.JPG

Glue tabs are scored and folded, ready for gluing
PICT0330.JPG

Glue applied to bottom glue tab
PICT0334.JPG

Bottom fuselage glued
PICT0337.JPG

Bottom Tail boom is next for gluing
PICT0341.JPG

Tail boom glued
PICT0343.JPG

Next will add the fuselage nose weights and super strong supports for when it hits something hard and fast!

Mike

[mbauer]

This step will add the nose weights and also supply strong support for the fuselage nose.
Bottom Front Nose is ready for gluing
PICT0347.JPG

Bottom Nose glue applied/Pre-shape bending completed
PICT0349.JPG

Bottom fuselage nose glued/also shown is the white dotted line for the rubber band hook, don't cut yet wait until final assembly steps
PICT0353.JPG

Scoring fold line on rudder, tool is art embosser for metal foil art work. Ball on end is 1mm in diameter, you can use wax paper or dryer fabric sheets to help it glide when scoring
PICT0354.JPG

Back to fuselage nose: nose lamination weights/supports need 3 for each side of fuselage
PICT0387.JPG

Gluing the laminates
PICT0391.JPG

First laminate gluing
PICT0395.JPG

All 3-laminates glued ready to cut out
PICT0398.JPG

Right side weight laminate cut out
PICT0399.JPG

Right side marked as is the left; Left side ready to install into fuselage-glue is ready to go
PICT0402.JPG

Final steps on nose weights next.

Mike

[mbauer]

Left Side nose weight is added
PICT0405.JPG

Check fit by folding glue tabs while glue still wet, if it won't move, you can trim any of the weight sticking up to far with a really sharp knife
PICT0410.JPG

Both balance weights added, glue applied for final nose assembly step
PICT0411.JPG

Front fuselage is completed
PICT0415.JPG

Fuselage aft top ready for gluing
PICT0417.JPG

Glue applied
PICT0423.JPG

While fuselage glue is drying, added some clamp weights to keep it flat
PICT0431.JPG

Edge coloring rudder fold line
PICT0433.JPG

Final parts to make
PICT0436.JPG

Wings are next.

Mike

[mbauer]

Cutting wings out using a quilting ruler with anti-slip mat glued to bottom. Mat is from kitchen section at store, drawer liner mat
PICT0360.JPG

Notice cut lines extend past part, helps insure clean cut and good separation of part from scrap cardstock
PICT0365.JPG

Wings cut out, time for edge coloring
PICT0373.JPG

Dry fit of wings to make sure fold line is correct
PICT0374.JPG

Gluing wings
PICT0376.JPG

Wings glued and drying-Note knife pointing at Center of Gravity (CG) locations. This is the spot where you balance model for flying, should hang level
PICT0381.JPG

Time to laminate the rubber band hook 1st gluing of both halves
PICT0439.JPG

Rubber band hook lamination #2 gluing
PICT0411.JPG

Rubber band hook ready to glue both halves and edge color too once glued together
PICT0444.JPG

Edge coloring complete, ready to install into fuselage
PICT0448.JPG

Final assembly steps next.

Mike

[mbauer]

Final steps to get the model ready for flight.

Cutting out the location for adding the rubber band hook, it is now time to cut the remaining dotted lines for the wings, rudder and horizontal stabilizer/ rudder
PICT0451.JPG

Rubber band hook is glued into position
PICT0453.JPG

Wings are inserted, glue after they are aligned in the wing opening, top and bottom of wing gluing required to make them strong
PICT0456.JPG

Top view of wings after gluing
PICT0458.JPG

photo with the first F4 made
PICT0461.JPG

Horizontal stabilizer aligned & then glued same as wing, top and bottom, make sure to get alignment with wing and rudder close, after drying they can be bent as needed for alignment, but accuracy now makes it easier and a better flyer
PICT0462.JPG

Checking alignment of flying surfaces
PICT0466.JPG

Model is drying
PICT0467.JPG

Will up load model next.

Mike

[mbauer]

Just updated the F-106 Dart to the new way of construction.

For this model I had to use a two piece fuselage width for the top front and nose. You can see where the glue butt joint is just aft of the canopy.
PICT0468.JPG

PICT0469.JPG

PICT0474.JPG

F106 weighs in at 8gm total.

Just realized I need to fix the flag direction. Good thing I took these photos...

New version weighs a gm less than old style.

Not sure of the next model to convert, B-47 or B-52...Possibly the ME 262, F104, ME163 or draw completely new design, F15, F16, F22 or F35...

Mike

[Don Boose]

Rubber-launched gliders are always fun. That F-4 is really classy.

Thanks for all the info and images.

Don

[mbauer]

Thank you Don. There are several paints of the F4, just need to update them.

XB-70 Mach 3

Needs some work on the structural for the fuselage. Added more strength and updated some of the graphic errors, USAF upside down, engine intakes.

Some photos of the XB-70 Mach 3 Bomber while it is drying:
PICT0476.JPG

PICT0477.JPG

PICT0478.JPG

PICT0479.JPG

Fuselage is thin and weak. This one a little difficult to build without warping.

Mike