(1248)Estes Patriot M-104/ Overhaul

[JERRYR708]

The Patriot was my first rocket purchases as a BAR. when Walmart had Aisles full of Operation Freedom and X-Prize scale kits that rekindled my interest. My Patriot finally saw it's maiden flight on March 18, 2014 right after completion for a total of 8 flights on B6-4 and C6-5 engines.
The last flight was a 2 Payload Flight on a C6-5 engine:
1) Estes Altimeter: 288 ft
2) 808 #16 keychain camera attached with velcro and blue painters tape
TTl gross weight: 4 3/4 oz
Note: The double payloads extra weight, camera drag, and stock square fins resulted in low altitude of only 288 Ft. The Patriot was under powered and leaned toward the weight of the camera and came down ballistic and then ejected fully just before touchdown.

I have decided to overhaul the Patriot
1) Engine upgrade to 24mm, 2) Kevlar #300 attached eyelet at M.M, 3) fill spirals and wood grain, 4) bevel fins, 5) Add Engine Retainer Ring, 6) Reinforce B.T. couplers with epoxy, 7) larger 3/16" x 2" Launch Lug.
8) Remove stickers, repaint rocket and paint roll pattern and add new US Army stickers

 

[JERRYR708]

The 8 flights had heated the wood glue and loosened the forward centering ring which made the motor mount removal easier. I just had to gently carve out the aft ring with an Xacto knife.

 

[JERRYR708]

I carefully carved out the shock cord and shock cord mount with an xacto knife which took quite awhile. I sanded both ends with 220 grit sand paper to remove glues and motor mount paper/elastic until smooth and cleaned them up with finer grit paper. I then dry fitted a coupler in both ends of the B.T. to make sure they were smooth with no bumps or tight spots,

 

[JERRYR708]

Purchased a 24mm Motor Mount for BT-60 from JonRocket.com to replace the stock 18mm motor mount. The kit has plywood centering rings to upgrade from cardboard. I assembled the motor mount using BSI epoxy and used the engine block since I only plan on using D engines or RMS 24/40's. I started with 100lb Kevlar tied to the engine block, then I found my 300 lb Kevlar, so I attached it to a screw eye at fore centering ring. I used a heat shrink tube over the screw eye and a few inches up the kevlar to protect from hot gasses. The Patriot now has 2 Kevlar cords. I also made a loop at the othe end of the kevlar and used heat shrink tube on the knot. I coated the centering rings and Kevlar knot at engine block with epoxy.
Now is a good time to reinforce all of the B.T. couplers. I ran a skewer stick inside the B.T. until it hit the couplers and marked them at the end of the B.T. I mixed some BSI 30 epoxy and coated all the coupler joints. I figured that if my motor mount aft ring was loose, the aft coupler in the B.T. is on its way to. I made sure that I wiped the inside of the B.T. real good with 91% isopropyl alcohol to clean all the black powder to help the epoxy bond.

 

[JERRYR708]

I scraped off the 1/8" launch lug to upgrade to a 3/16" lug for the bigger engine. All of the peeling, bubbling and torn stickers are coming off and will be replaced with all paint including the roll pattern. The U.S.ARMY may get painted or may get fresh stickers. I have to practice lettering first.
I wiped the tacky decal areas with goof off, then 91% isopropyl alcohol which dries very quick so that it wont soak into the cardboard tube. I sanded everything and added 3 layers of Titebond II glue fillets to fin/body tube joints.

 

[JERRYR708]

I epoxied the motor mount into the B.T. this way there is more time to adjust the fit and less B.T. shrinkage at the centering ring glue joints. I adjusted the Kevlar loop to allow the shrink tube knot to line up with the edge of the B.T. and still be able to have easy access to the loop. I also epoxied a plastic motor retaining ring to the engine tube. I scuffed up the plastic to allow the epoxy to get a good bite.
I decided to put a beveled edge on the leading and trailing edge of fins (I didn't know about this technique until I discovered TRF).
I used an Estes Rocket Marking tube guide slider V piece to sand a bevel on the fins. I set each fin on a flat surface along with the slider and taped sandpaper to it and sanded back and forth. It had the perfect angle to give all my fins a small amount of consistent bevel. I then used Krylon 2 in 1 sandable primer over the whole rocket. Filled spirals and grains with MinWax wood filler and sanded again with #400, #600 sandpaper until smooth. Wiped down with 91% isopropyl alcohol before paint.

 

[JERRYR708]

I masked the rocket and painted all the designated white areas with 3 coats of paint and removed tape right away to prevent the tape from lifting up the fresh paint or leaving a hard paint line. I waited 3 days for paint to dry and then masked off the white roll pattern to prep for the black roll pattern. I traced the old black roll pattern stickers over the 3M painters blue tape and cut with new Xacto blade. I masked off all other non white areas of Patriot with 3M blue painters tape and plastic bag and painted 2 light coats of black and a final thicker coat. I waited another 3 days and masked off rocket except for the yellow upper tube section and painted it with 3 coats of yellow. Will have to wait another 3 days to paint the final color of red....

 

[mbeels]

That's looking really good, it will be a whole new rocket. Nice work with the painting and masking!

 

[Bruiser]

At first I was just thinking you'd be better off with a new kit when you wrote it cam down ballistic but I guess the parachute had just enough time to open, lol! You are doing excellent work there. It's coming out great.

Will it need nose weight with the larger engine and plywood motor mount rings?

-Bob

 

[JERRYR708]

Finished painting the Patriot the Final red paint with 3 coats.
What I have learned from all of this:
1) Don't wrap copy paper to cover the rocket before painting. I painted the white base coat of the rocket and waited a few days. I covered the middle of the rocket with copy paper, wrapping it more than once and masked the ends to paint the black roll pattern. When I tried to remove the copy paper, it stuck to the whole rocket. I had to peel the paper off along with the white paint. It was a gummy mess.
2) Do cover over the inside vent holes with masking tape. When I painted the red end of the B.T. some of the red paint escaped through the covered end and found it's way into the vent holes and put red flares on the yellow section when I removed the tape.
3) Use Tamiya or Scotch Magic tape to mask off my models for roll patterns etc. for cleaner lines.

I had to sand the whole rocket and start all over again. The paint job is not as clean as the first round. I can see high and low spots, paint overlap from the previous paint application. I can also see sanded paint edges from sanding the ridge lines where the white meets the black roll pattern. I thought I could get away with 1500 grit sand paper over those areas, but you can see the gloss paint is more satin in those areas. Small bleed dots along some of the paint edges can also be seen. Still looks better than the old decals that I removed

I'm going to go back and clean up these minor imperfections with spot masking and painting.

 

[JERRYR708]

I reinforced the B.T. ends with thin CA glue and a latex glove. Since the Patriot will now be flying on mostly D 12-5 engines, weight will need to be placed into the nose cone to counter the difference for stability (as Bruiser mentioned). The D 12-5 weighed at 46 g and the weight of the C 6-3 was 24 grams. I kept adding clay( 22 g )next to the C 6-3 engine until the combined weight matched the weight of the D 12-5 engine. I rolled the clay into a small enough size rope to feed into the hole of the nose cone. I then rammed the loose clay with a round wooden dowel to pack it into the tip of the nose cone, being careful to keep the clay evenly balanced inside.

Next installation was the 1/4" x 72" shock cord. By the time I tied a knot on both ends and a loop in the middle for a chute, it reduced the length down to 64 inches. A little more than 3 X's the length of the rocket. At the Kevlar loop coming out the B.T., I used a snap swivel, which is attached to a 3/8 dia. split ring hoop, which is attached to the shock cord. This part of the shock cord is 3' 10" long before a loop is made for the 18 inch parachute to be attached to it with another snap swivel. The last 1'6" of shock cord was then tied to another snap swivel and fed through the orange 6"x 6" Nomex chute protector and then the end snap swivel was finally attached to the nose cone loop.

The total weight of the Patriot loaded with full recovery harness and D 12-5 engine and ready for launch is 180 g or 6 1/4 oz.
This still doesn't account for any electronics (Altimeter and/or 808 camera) which will be used later for test results.