Quickie

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

DigBaddy

It's OK to not know something
TRF Supporter
Joined
Feb 19, 2021
Messages
1,729
Reaction score
3,669
Location
SE, WI
That's the best name that has come to mind. No pun intended.

Started with the tube. I think it was from either a roll of food saver type bags or maybe butcher paper. It's thick and heavy-ish, but happened to just have the same inside diameter as BT-55. I had an extra conical nosecone in the parts pile and plenty of other stuff to make this reality, quickly.

The first bit of fun was working the nosecone with such a fat tube. I considered adding a small piece of normal BT-55 and a long coupler and adding a transition to it. Then I dug through my styrene supplies and a piece of square styrene around the shoulder of the nosecone just happened to match the outside diameter of the tube. Ok, I can work with that. A bit of sanding on the front edge and some Bondo and we have a more workable profile.

IMG_20221227_092340535_HDR.jpg

IMG_20230109_193839265_HDR.jpg

The name tells us this is meant to be brought down in a hurry. So, I made a fin profile very similar to an Estes Hi flier. Tinkering in Open rocket accidentally got me there. Wanted the fin to be positioned a bit ahead of the rear end of the rocket and not sweep to the rear. These gave decent stability without requiring much nose weight (which will be about 12g). I may need to clip on a couple more grams with a 24/60 reload if I get crazy.

Fins are 3/32 basswood, papered. Still light and seem quite strong. Recovery will be by mylar streamer.... probably 5x50" or so.

I only went with a 24mm mount so I can go through the wall fins.....but there could have been pretty stubby tabs with 29mm. Cheap flights are better too.

Sims to 2100' on a F24 and will fly great on the 24mm Q-Jets, but I suspect it'll commonly eat D12-5 s and E12-6s. It actually sims ok on C5-3 and C11-3 motors to about 300'. Got quite a range this can fly on.

Not sure how I'll paint it yet...

IMG_20230112_162026928.jpg
 
I'd have sanded the front of the BT to continue the taper of the BBII nose cone until it reached the full OD. Make gosh-darn sure the NC is in there straight, sand a bevel at one point to establish the length of the transition, then mark a circle on the BT and bevel it to the line all the way around. Break the corner if you want once it's geometrically correct.
 
I'd have sanded the front of the BT to continue the taper of the BBII nose cone until it reached the full OD. Make gosh-darn sure the NC is in there straight, sand a bevel at one point to establish the length of the transition, then mark a circle on the BT and bevel it to the line all the way around. Break the corner if you want once it's geometrically correct.

That doesn't sound quick. 🤪
 
What does sound (reasonably) quick is to build up that bondo more and bevel the leading edge of the polystyrene band a bit. If you want to.

That would be. Maybe I will. Maybe not. I got a doorknob to paint and maple syrup season is knocking. Gotta get tubing up, so rocket time will dwindle.
 
Ready to fly. Mylar streamer installed, painted, chunks of vinyl trimmings from a different effort slapped on. Cleared. Once I get a D12/E12 through it I'll give it a spank with an F44 on a calm day. Should more than hold up to that.

View attachment 560412
Looks good! The scheme is sort of “magic hat” like - matches the look of the cone…I’d name this The Sorcerer’s Apprentice 🧙‍♂️
 
Back
Top