Delta IV Heavy 1/89.4 scale

[Raptor 2]

I will be constructing a Delta IV Heavy /89.4 scale based on BT-70 center core and boosters. 24 mm motor tube will be able to carry Estes E motors. First on the line will be the construction of three nose cones each made of 4 cardstock transitions, 8 centring rings around a BT-20 center tube topped with a 20mm wood ball (side boosters)or plastic ball(center core). The tubes will have wraps by AMX paper space scale modelling.

 

[NOLA_BAR]

Love the AXM models. I always thought about doing the Delta IV Heavy with the Orion EFT. RSR/DFR Tech. had a nice kit.

 

[Raptor 2]

Completed the three nose cones. One coat of primer/filler,sanded,wood filler on the transition joints,sanded and one more coat of p/f and final sanding. They are now ready for the white overcoat. Completed construction of the 24mm motor mount. Spliced the 12” long TW motor tube and the main center tube just above the thrust ring location. This gives me easier access to glue the motor mount to the main tube. I then add home made couplers to the MMT and the main tube. Added a 55mm extension to the TW motor tube to decrease the volume for pressurization at chute ejection. Installed an ejection baffle just above.

 

[Raptor 2]

Completed the application of all the body wraps using 3M double sided tape. Glued the nose cones to the SRBs and center core. Added the conduits to the back side of the model. Constructed from 1/2 round plastic strips .187” dia with a wrap exterior. The conduits were secured to the tubes again with double sided tape.

 

[Hobie1dog]

using card stock for nose cones has never worked for me, glad your's turned out good.

 

[Raptor 2]

using card stock for nose cones has never worked for me, glad your's turned out good.

They are a lot of work and challenging to build, especially the curved ones.

 

[Raptor 2]

Completed detailing and securing the boat tails to the boosters. Added details to the bottom of the boosters and have glued the three tubes together.

 

[Blast it Tom!]

That's very nice work! T'would be wonderful to see all three lit, but that is begging for trouble! Keep this beauty safe!

 

[lakeroadster]

A truly beautiful build. Well done.

What will you be doing to address stability? Lexan fins?

 

[Raptor 2]

I construct fin tubes using SIG Plastic sheets .04” thick. I interlock them inside slotted BT 20 tubes which are inserted into three spaced out centering rings in each of the side boosters. They are a tight pressure fit but can be removed and replaced if required.

 

[Huxter]

Gorgeous rocket - great build. I like the removable, but solid fit of the fins/tubes.

 

[Raptor 2]

Completed adding the upper common booster core horizontal struts. Inserted the fins into the side boosters. The model stands 33-5/8” including the fin tubes and weighs in at 450 gm (15.87oz) including a 30” chute. She will fly in the spring on on E and F motors.

 

[Dissonance]

Excellent!

 

[Hobie1dog]

 

[Blast it Tom!]

Very nice collection in the background, too!

 

[Raptor 2]

Thanks for all the nice comments. Much appreciated.
Yesterday turned out to be a great day to launch a few rockets. 23 Degrees and lite winds. So my grandson and I flew two of his Estes models. The Double Ringer and the Terra GLM. Both of which flew straight and high with great recoveries on chutes made from plastic Walmart bags.
Then it was time for the maiden flight of the Delta IV Heavy. I tried to load an Aero-tech E30-4T but it would not seat properly in the space between the engine mount tube and the metal clip. It was too short to engage the back end end of the motor. An error in construction. Soooo .... I loaded an Estes E12-4. The model had a slow lift off and was stable in flight but did not gain enough altitude for the 4 second delay. She arched over and nose dived into the ground. Ejection charge is visible just before impact in the attached slo-mo video. Dumb, dumb mistake!!!!! Main nose cone and tube crushed down to the tube coupler and the SRBs disengaged form the main frame. Post mortem....she is repairable but this is a lot of work and will happen over the the up coming cold winter months.

View attachment C43AD40E-4F06-429C-849D-FA28ABD9CEA7-28807-00000389C5C3CA22.mov

 

[Blast it Tom!]

But... she IS repairable...

 

[Raptor 2]

Started the reconstruction of the model. Removed the nose cone and cut back the crumpled main frame to just above the American flag. This lines up with the top of the tube coupler which is probably what stopped the tube from crumpling further downwards. Will add a new 178mm long tube to the top. As the original tube coupler is right at the splice I had to add a 40mm length of tubing to the interior of the new tube to match the interior diameter of the original coupler below. Then I could add a new 70mm coupler at the splice. I hole punched these tube additions to help apply thin CA glue to more of the area of the tube surfaces. Constructed four new transitions for the nose cone from cardstock and lined two with an extra layer of cardstock glued on in sections. Then glued the centering rings to the top and bottom of each. Top transition ends with a 20mm wood sphere. All rings and cardstock were glued using RC canopy glue.

 

[Blast it Tom!]

That's the spirit!

 

[Raptor 2]

Mainframe and side boosters ready to be glued back together and the final installation of upper struts.

 

[Raptor 2]

All put back together again and ready to fly on an E30-4T this time.

 

[Dipstick]

All put back together again and ready to fly on an E30-4T this time. View attachment 617024

Beautiful model, and that motor will help. Thanks for sharing the repair...today I threw some crashed models out instead lol.