PDA

View Full Version : Another UPSCALE Der V-3 4" Tube


Thor
08-11-2005, 10:37 PM
Thinking about this one. A 1.5X Upscale of the BT80 (2.6" Tube) Der V-3
Trying to get it to fly on an E motor. The original V-3 would go 1100 ft on an E with a modified mount I think. Here is what I am thinking, trying to make it about 10.6 ounces total.
Body Tube-T-101 from Totally Tubular, 3.938" OD with a thin .021" wall-Should be 24" with an estimated weight of 2.6 ounces
Nose Cone-3.9" Standard cone from Loc/Precision Total length-12" approx, weight 5.0 ounce
5/16" Balsa fins- Estimated weight-1.5 ounces
Motor Mount for 3.75" E9-4- Estimated weight-1.0 ounce
Glue/paint 0.5 ounces Total 10.6 ounces

The 1X Der V-3 is a 24" rocket with a BT-80 body tube. This upscale 1.5X would be a 36" rocket with a 3.94" body tube. Should fly low and slow. Plan on a 1/4" rod about 6' long to launch it. Paint scheme solid red like the original.

CPMcGraw
08-11-2005, 11:26 PM
Thinking about this one. A 1.5X Upscale of the BT80 (2.6" Tube) Der V-3
Trying to get it to fly on an E motor. The original V-3 would go 1100 ft on an E with a modified mount I think. Here is what I am thinking, trying to make it about 10.6 ounces total.
Body Tube-T-101 from Totally Tubular, 3.938" OD with a thin .021" wall-Should be 24" with an estimated weight of 2.6 ounces
Nose Cone-3.9" Standard cone from Loc/Precision Total length-12" approx, weight 5.0 ounce
5/16" Balsa fins- Estimated weight-1.5 ounces
Motor Mount for 3.75" E9-4- Estimated weight-1.0 ounce
Glue/paint 0.5 ounces Total 10.6 ounces

The 1X Der V-3 is a 24" rocket with a BT-80 body tube. This upscale 1.5X would be a 36" rocket with a 3.94" body tube. Should fly low and slow. Plan on a 1/4" rod about 6' long to launch it. Paint scheme solid red like the original.

Thor,

You're not too far off the numbers, but you might be a bit disappointed with the E9...

The weight of this model has to include a parachute. I chose a LOC 36", which brought the empty weight to 14.08 oz.

E9-4 only gets you 283', with a deployment V of 44 fps (rather high). BIG KICK IN THE PANTS HERE -- It requires a rod 310" long to reach flight V... :eek:

An E30-4 gets you much better performance -- 632' altitude, with a deployment V of 28 fps. Rod length 38"...

An F24-4 gets you 759' with a deployment V of 22.2 fps. Rod length 48"...

Best performance is with the F32-5. Altitude of 1300', with a deployment V of only 22 fps. Rod length 39"...

CPMcGraw
08-12-2005, 12:21 AM
Thor,

I went back and used LOCs matching 4" tube instead of the T-101/BT-101 size tubing in the first version, since the E9 is pretty much ruled out for any version of this model. The results look much more interesting, and the deployment Vs are far better.

The launch rod lengths increased along with the empty weight:

Empty -- 19.42 oz

E30-4 -- 53" rod, 461', 10.1 fps deployment V;
F24-4 -- 65" rod, 561', 8.77 fps deployment V;
F32-5 -- 54" rod, 1100', 18.57 fps deployment V...

Thor
08-12-2005, 08:35 AM
Thanks Craig, I appreciate the rocksim work. I thought the 0.021" wall 101 would be lighter than the loc tubing. Wonder what the E9 would look like with a D12 booster added. I am wanting to stick to Estes motors so I may have to go back to the original BT80. I also saw where folks were using a bottom booster WITHOUT the stage, they called it CHAD staging, CHeap And Dirty! :D Thanks a lot, I would rather get this good info up front than spend time and money on a big red lawn dart. :eek:

CPMcGraw
08-12-2005, 12:12 PM
Thanks Craig, I appreciate the rocksim work. I thought the 0.021" wall 101 would be lighter than the loc tubing. Wonder what the E9 would look like with a D12 booster added. I am wanting to stick to Estes motors so I may have to go back to the original BT80. I also saw where folks were using a bottom booster WITHOUT the stage, they called it CHAD staging, CHeap And Dirty! :D Thanks a lot, I would rather get this good info up front than spend time and money on a big red lawn dart. :eek:

Thor,

All it really needs is the application of power...

Try a Triple-Delta, or Triple-Eagle, version (three motor cluster)...

See attached RKT file.

Thor
08-13-2005, 02:58 PM
Craig, how does it look with a single D12 booster followed by a single E9-4 in the upper stage? If I could get 500' out of that combination I would be happy. I dont have the software or knowledge to look at the file you have linked. Thanks!

Thor
09-06-2005, 04:35 PM
Ok Craig, I see if I want a rocket that big, I need to increase the thrust. So if we go with the 4" Nose cone and Loc tubing what do I need to get to build a 29mm motor mount. The biggest I have build is for an E/F mount. I assume TTW fins into the outside of the motor tube but how is the larger motor retained or blocked? Thanks! Might make this one to take up to a G 29mm motor. Thor

Green Dragon
09-06-2005, 04:42 PM
couple comments on this thread.

first off - the LOC cone is rather heavy - if you can get your hands on an old ACE 3.90 cone or even an Aerotech 3.90" cone ( wrong geometry though, the Ace would be ok ) .
Ace = a lot lighter, but not sure who is selling those now, Magnum had some, but not sure who has the molds these days,etc.

( would be willing to buy a dozen of those cones myself if anyone knows a source ) .

as for the motors - no reason a Der V3 should not be stable enough fo rthe chad staged D12, I've flown my 100% stock Maxi-Alpha 3 on three stage d12's all chad staged, hanging out in the air....

I do agree with other comments,however, if you want to avoid composite motors, and stick with Estes, then why not clustered 2 or 3 D12 ?

I htink 2 x d12 will fly as well as the D12 to E9 chad flight, and 3 x D12 = higher impulse and better flight, heck, we used to fly our BEAST rocket (5.375" dia x 3 pounds ),on three D12-3, althogh 5 x D12-5 was better :-)

good luck and post some flight pics when ready :-)

~ AL