Hybrid modeling 3D Printed shell with conventional internals

[OG1959]

Really enjoying 3D printing the rockets then adding conventional internal mounts. It's challenging and rewarding. I find myself becoming more adept with modeling and prototyping. Something as simple as mount rings designed to be glued on a tapered ABS body shell can be tricky but rewarding when it's fits and glues in securely.

The gray V2 is set up for A - E, even F motors. Starting small though.

The Mini V2 is the same. The X-15 is getting a single A motor mount glued to a B-50 tube mounted to the fuselage with a 3DP ring.

All will have parachutes below the nose cone but the Mini V2 will have it stowed IN the nose cone. Motor mount anchored kevlar shock cord is connected to parachute lines along with elastic shock cord which is then tied to a short kevlar leader terminating in the upper portion of the nose cone. That's what's laying in the bench, white ring, kevlar leader. That goes in the nose cone and elastic ties to the kevlar leader.

I'm counting on full ejection of nose cone and contents in one push. Kevlar cord from lower stage goes tight and pulls parachute from nose cone bay. Shock cord deploys as mass of nose cone continues onward but slows down as the parachute deploys.

Wil it work? We'll see.

 

[OG1959]

The X-15 is nearly ready for a test launch.

I made an anchor ring and set it deep in the body tube with a length of Kevlar attached.



3D printed a plug and attachment point for the nose cone. I designed in a screw that keeps the plug/anchor in place. When removed, there is access to the nose area so weight can be added.



The shock cord is elastic folded over on each end with a shoelace grommet installed. 1 3/8" snap swivels are used to anchor all cordage.



Loaded with an A10 motor, wadding and a chute it's CG is at the dot on the picture, very close to being in line with the wing's center of lift. No weight was added to the nose and it swing around nose first on a string. It also held stable tail first so maybe I'll add some weight to the nose and check it again. I think it will fly just fine.



Planning on a little paint and some stick on decals.

 

[neil_w]

Very nice work.

That is clearly an eyeball, and don't try to convince me otherwise.

 

[OG1959]

Small....

 

[Cape Byron]

That mini V2 has me eyeing off a yet to be started Spacemonkey kit and a razor saw...

 

[hermanjc]

I agree, hybrid approach works great and really allows you to shape your rocket in any custom manner, whether based on an OOP kit with rare transitions and nosecones or something totally new.

Looking great! I love the X-15 especially.

 

[Sandy H.]

[snip]
Something as simple as mount rings designed to be glued on a tapered ABS body shell can be tricky but rewarding when it's fits and glues in securely.
[/snip]

It seems you're indicating that either the fit or glue doesn't always work the first time. Have you tried making 'bumps'/'waves' to allow room for epoxy to rest in while you assemble components and the final cured assembly would have a level of mechanical joint even if the epoxy wasn't perfect? Just curious, not suggesting from experience.

Sandy.

 

[OG1959]

More about the fit. designing and 3D printing a properly sized tapered a ring is tricky. When you get it right it just feels good! It becomes a point of pride in the build.

 

[OG1959]

I found a decal sheet online, downloaded it and printed it on some white vinyl sticker material. Background was black in the image so it worked out good. Makes all the difference!
It weighs in at 3 oz ready to launch.