Brief:
A simple LPR single stage, motor deployed chute recovered tube fin rocket.

Construction:
1 - 24" x 3" BT, 1 24" x 3" BT for fins, me hearties, 1 chute, 29mm MMT and 2 CR's, a nose cone, ya bilge rat, shock cord and a launch lug.

I was asked t' write a review on me scratch built Circle Jerk. Avast, me proud beauty! I hadn't documented any o' t' construction, matey, so I decided t' build another one, but this time I documented t' process. Begad! Avast!

For both birds I used 3" USR "whitewall" tubin' because o' its thickness. It's twice as thick as any other tubing. I felt that it gives a better appearance t' t' tube fins.

I cut all o' me tubin' with a 12" DeWalt compound miter saw. I use a special rippin' blade that has more teeth than most blades. Avast, me proud beauty! This gives a smooth cut that needs very little work. Blimey! T' softer paper tubes do fray a little but that is solved by soakin' t' ends o' t' tubes with thin Cyanoacrylate or thinned wood glue. Arrr! When t' glue hardens, just sand t' ends t' t' finish you need. Begad! For phenolic tubes, shiver me timbers, shiver me timbers, it gives a factory like finish.

T' first picture shows t' tube bein' cut and t' jig I used. Blimey! For this rocket, I made all cuts at a 45-degree angle. Avast! Arrr! T' original had just t' forward cut at a 45 and t' aft cut at a 90. Aye aye! I just wanted t' do somethin' different this time. Begad!

If you use t' same diameter tubin' for t' fins as t' body tube, you will need 6 fins. Avast! All tube fin rockets work this way. Avast, me proud beauty! (Do t' math) Attachin' the fins is elementary. Well, blow me down! Draw a line around t' tube where you want t' forward tip of t' tube fins t' be. Ahoy! Put a bead o' glue (I used wood glue) on t' first fin and align it on t' BT. If you lay it on its side on a table they will be parallel t' each other. Ya scallywag! No more thinkin' will be necessary because the subsequent fins just lay on t' last fin and t' BT. Well, blow me down! For t' next fins, shiver me timbers, just find where t' tubes touch, matey, ya bilge rat, draw a line and put t' glue there. Blimey! Begad! T' final fin will snuggle up betwixt t' last fin applied and t' first fin. Avast, me proud beauty! Ahoy! Use fillets as you see fit, but they are nay necessary for strength because each fin is glued at 3 points. Avast! Well, blow me down!

It's tough t' find t' CP on tube fin rockets like this but it's safe to say that its somewhere in t' fin section ;-) Just make sure t' CG is forward of t' fin section with a motor installed. Well, blow me down!

Flight:
For t' original rocket, I used a standard 29 mm motor mount tubes cut t' 6 inches. Ya scallywag! Ahoy! T' centerin' rings (2 o' them) were just 5 ply rings I had laying around. Ahoy! Begad! T' 32" parachute and t' shock cord be from a lawn-darted Aerotech Astrobee D. Begad! Ahoy! T' nosecone is a 3" PML. Ahoy! T' launch lug is just a ¼" Aerotech igniter tube. Begad! Blimey! (OK, yeah I'm cheap) T' final weight is about 24oz. Ahoy!

For flying, matey, I always use dog barf and friction fit motor retention. Well, blow me down! Ahoy! She flew straight as an arrow on several F and G motors. Arrr! Begad! Fun t' fly.

Summary:
This is a quick and easy rocket t' build. Its different than most tube fin rockets and draws a little attention. Blimey! Nay countin' t' paint, matey, shiver me timbers, shiver me timbers, it took all o' an hour t' build.