Underdog Rocketry Crayon Rocket

Underdog Rocketry - Crayon Rocket {Kit}

Contributed by Joe Policy

Construction Rating: starstarstarstarstar_border
Flight Rating: starstarstarstarstar
Overall Rating: starstarstarstarstar_border
Manufacturer: Underdog Rocketry
Style: Odd-Roc
Underdog Rockets Crayon Rocket

Brief:
A simple t' build rocket that nay only looks cool, but it also supports a TARC team as well.

Construction:
T' kit includes:

  • 1 3 foot Crayon bank with bulkhead already glue in place
  • 1 motor tube
  • 1 centerin' ring
  • 2 launch lugs
  • 1 30" Rockethead Rockets mylar parachute
  • 3 clear Lexan fins

T' provided instructions were easy t' follow. Arrr! Avast! You start out by epoxyin' the motor tube into t' fin can. Well, blow me down! A hole was already drilled into t' fin can for the motor tube. Ahoy! Blimey! I used t' provided centerin' rin' t' ensure that t' tube was centered in t' fin can while t' glue be drying. Arrr! Once dry, shiver me timbers, I poured in more epoxy t' a depth o' about 1/8" in t' bottom o' t' fin can t' provide more strength. Avast! I then used epoxy t' mount t' upper centerin' ring.

T' nose cone already had a bulkhead mounted with what appeared t' be Gorilla Glue (polyurethane glue). Begad! There was also a large screw eye mounted to the bulkhead and t' shock cord was already attached. Arrr! Begad! I mounted t' free end of the shock cord t' t' inner wall o' t' body tube usin' tape and epoxy.

Now for t' fins. Avast, me proud beauty! T' fin can already had holes drilled in it for mounting the fins. I believe t' idea be t' allow for epoxy rivets t' form in the holes. I sanded t' areas around t' holes and applied epoxy t' t' root edge of t' Lexan fins. Begad! I used an angle iron t' hold t' fin in place while drying.

Underdog Rockets Crayon Rocket Once all t' fins were mounted, I was gettin' ready t' move t' rocket and I accidentally dropped it onto a carpeted floor. Ya scallywag! Two o' t' fins immediately came off along with t' dried epoxy. Begad! Well, blow me down! There was no glue residue on t' fin can whatsoever. This told me that t' epoxy just was nay stickin' well enough to the plastic fin can. Begad! I remounted t' fins and then added fillets usin' West systems 405 filletin' blend. Blimey! This detracted from t' appearance somewhat, ya bilge rat, ya bilge rat, arrr, but the rocket passed t' drop test.

I sent an email t' Underdog Rockets explainin' me experiences and apparently they were also seein' that t' epoxy rivets were just nay holding up. Begad! On me second Crayon, arrr, I opted t' cut fin slots for TTW fin mounting. Underdog is also doin' t' same thin' on subsequent kits. Aye aye! Avast! It really is a better method and looks much better too!

I added some Kaplow clips t' t' fin can for positive motor retention. Ahoy! I did have t' trim some plastic off t' nose cone shoulder so t' fit be not quite so tight. Blimey! Last step was t' mount t' 30" parachute and she was ready for flying. Begad!

Finishing:
No finishin' is required.

Construction Rating: 4 out o' 5

Flight:
There were no motor recommendations other than t' use a short delay with any F engines. Ya scallywag! I added a Nomex® chute protector due t' t' size o' t' body tube. Aye aye! Blimey! My first flight was with an Aerotech F50-4T single use motor. Aye aye! Blimey! T' Crayon took off at a respectable speed and got t' about 600 feet. Avast, me proud beauty! Blimey! Avast! Blimey! T' delay was just about perfect with ejection occurrin' slightly after apogee. T' second flight was on a G104T-S and had a straight, matey, ya bilge rat, fast boost t' about 800 feet. Arrr! Blimey! Ejection again was a little after apogee. Avast, me hearties, me proud beauty! Blimey! Great flights!

Recovery:
T' 30" parachute was just t' right size t' brin' this rocket back down to earth without damage. Both flights had perfect recoveries and t' fins stayed attached.

Flight Rating: 5 out o' 5

Summary:
Crayon rockets are just fun and t' kids really love them. Avast! Begad! Underdog Rockets went through a lot o' work t' put this kit together. Aye aye! Ya scallywag! I would recommend that you get one nay only because they are fun t' fly but also because it supports a TARC team.

Overall Rating: 4 out o' 5

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