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cobra1336
28th March 2010, 08:14 PM
Building a bic pen rocket. 3 ft. long, 2 inch diameter. Working on the nose cone now and cutting some Lexon fins. Was trying to decide on fin shape and I wondered, why not keep them square. 38 mt and have an 29 mm adapter. Will do some G motors at first depending on weight then up to maybe an H or I. Guessing at weight right now I would say I'll bee in the 2-3 lb. zone. My beer bottle rocket (3 lbs.) flys great on H motors but is a lead sled thru the air. So, would the sleeker pen rocket be O.K. with square fins? Fins are 4" tall X 4.5" long right now.

rokitflite
28th March 2010, 08:24 PM
Would that be "Lexan"?

cobra1336
29th March 2010, 12:30 AM
opps............yes lexan.............so, would square fins be O.K.?

dragon_rider10
29th March 2010, 07:38 PM
I hope that wouldn't be a glass beer bottle for that other rocket.

You would probably do better with tapered fins on the pen, if I had to guess.

ScrapDaddy
30th March 2010, 02:40 AM
Building a bic pen rocket. 3 ft. long, 2 inch diameter. Working on the nose cone now and cutting some Lexon fins. Was trying to decide on fin shape and I wondered, why not keep them square. 38 mt and have an 29 mm adapter. Will do some G motors at first depending on weight then up to maybe an H or I. Guessing at weight right now I would say I'll bee in the 2-3 lb. zone. My beer bottle rocket (3 lbs.) flys great on H motors but is a lead sled thru the air. So, would the sleeker pen rocket be O.K. with square fins? Fins are 4" tall X 4.5" long right now.

Where are you getting a 3 foot long pen? :confused:

Micromeister
30th March 2010, 02:50 PM
Cobra:
square Polycarbonate fins will be fine as long as the area is sufficent.

cobra1336
30th March 2010, 05:33 PM
Where are you getting a 3 foot long pen?

It's a scratch build. Found some 2" white tubing (not PCV) Had to scratch a nose cone from balsa and body filler (not done yet). Will look like a pen cap when done.

I did taper the fins a little last night. It is generally the same size as my Callitiso so I sort of copied the fin size but they have more surface area.

Micromeister
31st March 2010, 02:24 PM
Sure like to see some pics Cobra when ya get a chance.
I'm kinda partical to Skywriting Odd-Rocs LOL!!!

cobra1336
1st April 2010, 04:16 PM
I'm off tomorrow. I'll give it a shot.

cobra1336
3rd April 2010, 01:43 AM
got the nose cone done. here's some pics the cap is patriot blue the pics look black

cobra1336
3rd April 2010, 01:50 AM
The first couple of pics makes the pen cap look short, sorry about the photos, it is to scale and looks bigger / longer in real life

cobra1336
3rd April 2010, 01:52 AM
Last pic is about right

cobra1336
9th April 2010, 01:25 AM
Not done yet, but here you go