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. Well, me bucko, blow me down! You start out by epoxyin' the motor tube into t' fin can. A hole be already drilled into t' fin can for the motor tube. Arrr! Ahoy! I used t' provided centerin' rin' t' ensure that t' tube was centered in t' fin can while t' glue was drying. Well, blow me down! Once dry, I poured in more epoxy t' a depth o' about 1/8" in t' bottom o' t' fin can t' provide more strength. Avast, me proud beauty! 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). There was also a large screw eye mounted to the bulkhead and t' shock cord was already attached. Arrr! 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. Begad! T' fin can already had holes drilled in it for mounting the fins. I believe t' idea was t' allow for epoxy rivets t' form in the holes. Avast! Avast, me proud beauty! I sanded t' areas around t' holes and applied epoxy t' t' root edge of t' Lexan fins. Ya scallywag! I used an angle iron t' hold t' fin in place while drying.

Underdog Rockets Crayon Rocket Once all t' fins were mounted, arrr, shiver me timbers, I was gettin' ready t' move t' rocket and I accidentally dropped it onto a carpeted floor. Well, blow me down! Two o' t' fins immediately came off along with t' dried epoxy. Arrr! There was no glue residue on t' fin can whatsoever. Aye aye! This told me that t' epoxy just was nay stickin' well enough to the plastic fin can. I remounted t' fins and then added fillets usin' West systems 405 filletin' blend. This detracted from t' appearance somewhat, ya bilge rat, 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, I opted t' cut fin slots for TTW fin mounting. Underdog is also doin' t' same thin' on subsequent kits. Begad! Avast, ya bilge rat, me proud beauty! It really is a better method and looks much better too!

I added some Kaplow clips t' t' fin can for positive motor retention. Avast! Avast! I did have t' trim some plastic off t' nose cone shoulder so t' fit was not quite so tight. Begad! Last step be t' mount t' 30" parachute and she be 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. Ahoy! I added a Nomex® chute protector due t' t' size o' t' body tube. Avast, me proud beauty! My first flight was with an Aerotech F50-4T single use motor. T' Crayon took off at a respectable speed and got t' about 600 feet. Avast! Blimey! T' delay was just about perfect with ejection occurrin' slightly after apogee. T' second flight be on a G104T-S and had a straight, fast boost t' about 800 feet. Begad! Ejection again was a little after apogee. Avast! Great flights!

Recovery:
T' 30" parachute was just t' right size t' brin' this rocket back down to earth without damage. Ahoy! 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. Well, blow me down! Blimey! Underdog Rockets went through a lot o' work t' put this kit together. Arrr! Well, me hearties, blow me down! 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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