Patriot Downscale Build Part 9 FINISHED!

View from the back end showing the launch lug placement.

Install your preferred recovery device and you are ready to fly!
I put in a 1 3/4" wide X 32" long crepe paper streamer.

This is the PATRIOT ready for it's first launch on a 1/2A3-2t.
It's a great looking model, big or small!

Patriot Downscale Part 8 Launch Lug

The launch lug can be covered with a paper band.

I've cut some 24 lb. paper into a rectangle just a little longer than the 1" lug.

The starting edge is glued down the lug.

After that dries, roll the paper around the lug to find the overlap point and cut off the excess.

Here, I'm smoothing a glue coat evenly down the inside of the lug cover paper.

The cover paper was cut a little short on purpose. This gives you a little better gluing surface.

You can see how the paper was cut a little long and extends over the edges.

The excess is simply sanded off.

It's easier to roll paper around the tube if you don't have to sorry about matching up the edges of the paper with the end of the tube or lug.

Glue the lug beside one of the fin root edges.

Patriot Downscale Build Part 7 Fin Edge Dressing

If there is any warping of the fins, iron over them with a dry (no steam) iron. This should take out any turns.

Cut out the fins on the thin line from the "smaller" side.

I try to design my card stock models so one side of the fin print is larger than the other. This insures full print coverage and eliminates any chance of misalignment of the backside of the fin.



After cutting, the edges will be almost "too square".

Round off the outside edges of the fin using your burnisher.
Rub over the sides to knock down the square edges.





This picture clearly shows the rounded leading edge and the three ply outside edge.






You can get a better rounded fin by applying a bead of white glue to the edges.

Apply glue and let dry.
Lightly sand over the glue with 400 grit.
Reapply glue again and let dry.

Partriot Downscale Build Part 6 Engine Mount

While the fins are drying, the engine mount was made.

This rocket will use "t" or 13mm mini engines.

This is a standard mount, the engine will be a friction fit.

The BT-5 tube is 1 3/4" long.

The 1/4" long engine block was cut from a used 13mm engine.

The 5/20 centering rings are 1/4" long and cut from used engine casings.

The shock cord is two strands separated from a four strand 150 lb. piece of Kevlar.

The Kevlar was looped under the upper 5/20 centering ring.

Yeah, I know, I'm cheap! I'd rather build something than wait on an order.

Patriot Downscale Part 5 Fins

Set the fin over the straight edge of the cereal box cardboard.

Be sure the folded leading edge of the overlay is all the way down on the cereal box edge!

Check both sides of the leading edge overlay to be sure.

Burnish over the fins with your favorite hard smooth tool. I use a Sharpie pen quite a bit for this.

I did lay a piece of clean copy paper over the fin for burnishing.

Set the fins in a heavy book for pressing and drying.

Patriot Downscale Part 4 Fins

Making a three ply fin is explained over this and the next post. You should read both before proceeding.

For better glue adhesion, remove some of the print from your cereal box card stock. A few passes of 220 grit sandpaper will do the job.

Be ready, this makes quite a bit of colored dust.

Glue is applied to the slightly oversize cut fin. This picture is to show how much glue is needed.

Using a flat surface (a credit card or back of a razor blade) quickly smooth out the wet glue. You want an overall thin coating of white glue.

Patriot Downscale Build Part 3 Fin Overlay Leading Edges

TIP: I don't cut "halfway through" the card stock to make a fold like some instructions would have you do. I make a indented line down the fold line.

While the fins are still on the printed sheet, score the fold (leading edge) line. In the end this will give you a rounded leading edge on the three ply fins. The root and outside edges of the fins will be square.

Here I'm using the back side of a razor blade (not the sharp blade but the folded metal lip on the other side) to make the score. That rounded lip is a near perfect edge to score the heavy card stock.

I've placed wraps of masking tape over the blade so I won't cut my fingers with the sharp side up.

Use a straightedge to score the 110 lb. card stock. I score right over the top, on the printed area. If you don't press to hard, or go over the score too many times, you won't take off any of the ink.

After scoring cut out the fins a little outside of the black edge line and printed areas. In other words, cut a bit oversize.

Cut a long straight edge on your cereal box cardboard.

You want this edge straight! This edge will be right under the fold of the leading edge (printed) fin overlay.

Patriot Downscale Build Part 2 Body Wrap

The BT-20 was cut a little oversize, to around 8 1/4" long.

I like to trim and sand the tube down after the wrap is in place. It's easier not worrying about matching the top and bottom of the wrap to the length of the tube.

A pencil line was drawn down the length of the tube with an aluminum angle.

The long edge of the wrap will be aligned on the pencil line before wrapping around the tube.


The wrap is cut out before spraying with adhesive.

The wrap was turned over onto masking tape turned sticky side out to hold it in place for spraying.

Don't press the wrap down too hard on the tape. You don't want to lift any of the print when removing it from the spraying board.


The back of the wrap was sprayed with a really old can of Duro Spray Adhesive.

Start the wrap edge down the pencil line you drew earlier. If the line is straight, everything should match up on the other side.

Don't burnish down the wrap until you are sure it is straight.
If it isn't right you can carefully lift and reposition it.

Patriot Downscale Build Part 1 Parts

I can't believe I didn't take a picture of the parts all layed out!

This downscaled PATRIOT will stand 11.7 " tall by .736" diameter.
It flys with 1/2A3-2t, A3-4t and A10-3t engines.

Here's what you'll need to do the build it right along with the blog:

Main Body Construction Parts:
1 BT-20 8.1" long
1 BNC-20AH Nose Cone (available from Semroc)
1 SE-1 Screw Eye
1 ECR-124 Elastic shock Cord 24" long
1 SCK-12 Kevlar 8" needed
1 LL-110 Launch Lug 1/8" X 1" long
1 RS-236 Streamer 1 3/4" wide X 32" needed



Engine Mount Parts:
1 BT-5BJ Motor Mount Tube 1 3/4" needed
2 AR-520 Centering Rings
1 TB-5 Engine Block
Or you can build the engine mount using old engine casings like I did.

Go to Wayne Hill's Rocketry Blog HERE
Scroll down to the bottom and look for the Patriot.
Print out the main body tube wrap (first page) on 24 lb. paper
Print out the fins (page 2) on 110 lb. card stock.
Cereal Box cardboard is used for the interior ply of the fins.

Tony (tbzep on YORF) couldn't find the downscaled nose cone on the Semroc website.
He called Carl and asked him about it. Carl added it to the catalog!
I don't know where I got the nose cone I used to make the first downsized Patriot. I had it marked as a BNC-20AH.
On your next Semroc order, be sure to thank Carl for accomodating all space modelers.

You should be able to build this from spare parts like I did. You probably have most of this already.
We'll start the build on the next post.