New project - Need Ideas!

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Jun 30, 2010
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Ive just picked up a spacking new Big Daddy tube (BT-80) , same legnth as a BD tube & has the fin slots allready done :) And a BD plastic Nosecone. So I was looking at what I could use it for . I dont want to make a cluster , I could build it stock but thats kinda boring as I've allready got a converted clusterd BD 4x 24mm mmts.

Any Ideas would be great!
I'm just a tiny bit confused...are you sure it's a Big Daddy tube?

You probably are...the Big Daddy tube is not a BT-80 (2.6") The Big Daddy tube is 3".

If you can find a longer tube...make a big Patriot missle.

Or find another nose cone and make a bigger V-2!

Or make a booster section so your BD can be two staged.

Yep it's 3" sorry about that ,I thought BT-80 was 3".

I do have another BD nosecone to be honest lol! So how much do I cut off it ? And is the origional BD BT too long for a V2 so that it's scale? And could you suggest a mmt?

Could you give me some dimentions of the fins or a scale % so that I can downscale the fins please?
Thank you
It looks like...I think...he cut 3.25" from the tip of the cone to make a tail cone.

Give me a few minutes to do a drawing for you...BRB:D
Ok , I've cut the 3.25" off the top of the NC. Now I need a good way of filling in these fin slots that are pre-cut!
Thanks for doing a drawing Sandman!
I'm not sure how this drawing will scale but match up the dimention...maybe make the fins a bit larger.
Filling in the slots should be easy.

Make a paper backing and glue on the inside of the tube. Then fill the slots with pieces of tubing or balsa and use some "filler" to smooth over the gaps.
Why thank you sandman! So I take it the fins have to be sloped so that they fit onto the BT? I thought about dipping some normal printing paper into a mixture of PVA & water , and placing it over the slots. That would give me a surface to build up wood filler on.

Do the paper thing on the slots from the inside and fill the slots to match the outside surface of the body tube.

The fins are sloped to fit the tail cone. You will have to cut slots in the tail cone but the V-2 has some nice big fillets where the fins join the body so you don't have to be micrometer precise.

I highly reccoment "Through-the- Wall" fins on the nose/tail cone. it may be difficult to get a good bond with surface mounted fins on the tail cone.

Make the motor mount long enough (95mm) to take the New Estes "E".

You will be ready for the new Estes "E" motors when they arrive!:D

You are gonna love that motor!
Yep ! Hell yeah im gonna love that E! IIRC they are now legal and have all the H&S / CE markings needed :D Carn't wait to get my hands on some!
Last summer, something made me pick up and flip through a Las Vegas magazine at the local book store. A picture and short article about the 45th anniversary of the Stardust Hotel and Casino caught my eye. Part of the celebration is a time capsule in the form of a huge rocket approximately 24" in diameter and 15' long!

I was able to take some pictures and make some measurements of it on a trip last year and believe a good model can be built using a Big Daddy with different fins.

I just googled like crazy and came up with this small picture. It is halfway down this page:

Well shes nealy finished , CR's cut , bulkhead made for the NC , spirals filled , slots filled , just need the fins to be cut now.

Heres a few pics that I got round to taking today . The digi-cam is pretty useless but you can see how far ive got.

Coming out great so far.

I used 1/16" ply for the fins on mine (1.5mm) for a more scaled look and they weren't too heavy.

Build it light enough and it should be great on the "NEW" Estes E9.
Is there a re-design on the Estes E9? Im not going to bother with TTW fins , just nice , big solid fillets.
Thanks for the comment :)
I've worked out the excact scale for the fins , I will cut & shape them tomorow :)
Is there a re-design on the Estes E9?

There sure is!!

One big change over the Estes "D". The "E" is longer. The new Estes "E" is 95mm long!

Make a new engine hook out of a stainless steel strip from a wiper blade (Bosch blades are the best for this!).

Maybe you should just wait until you get an "E" motor before you make the motor mount just to be sure.

As for TTW fins...I'm just concerned about getting a good bond on the fins to the tailcone. Make some pin holes in the cone for glue 'rivets" if nothing else.
Thanks Sandman! Ive just took out a D12-0 and one of my E9-6's and theres alot of size difference there. So it must be one of the new ones :D Ill rough up the tailcone before aplying any glue , that should give something the glue can 'grab' on to. Ill cut the fins later , the weather just isnt good enough for flying anything at the moment.
Ok I weighed this bird in to . With a 18" Ripstop-Nylon 'chute , Centering rings , noseweight & a E9-6 she weighs in at 13oz . And this is without Fins or Fillets..... Looks like im gonna have to chad her after all , but I doubt that would work either :(

Have you considered making the fins a little oversized to reduce the amount of nose weight needed? Sounds like you might be approaching 15 oz once you get her finished and all loaded up. That's a lot to push even for a mighty D chad staged to your E9.

My 3in V2 weighs in at 28 oz but I over built it (a lot!) and included a 29 mm motor mount, dowel reinforcement, TTW fins, and a parachute bay for wadless packing.

Unfortunately, she's yet to fly. Haven't found myself in the right circumstances yet...

Good luck with yours--looks great so far!

I might have a E11 or E18 RMS on Saturday so maybe I'll fly her on that . It's just that the fins looked a little thick. Is yours more or less the same scale as mine? How did you draw out your fins ect? Do you have a template I can copy? I'm finding it hard to draw out the fins without having the needed angles.

IIRC, I uspscaled the fin templates in Alway's V2 book by 115% (2.6"-->3" scale factor).

Also, if you were going to go with oversized fins, you could use the fin templates from Jimz.


I printed out the fin template from my 3" V2 in rocsim and scanned. I used 75 dpi res to minimize bandwidth. Let me know if this is OK.

Oh, and just so there's no confusion, that "duh" was on me!

Thanks for that ! Could I ask you for a favor please? And use paint or something to add dimentions to that picture please :)


I'm confused!:confused:

I did a drawing with dimensions on it earlier.

Did you miss it?