Squirrel!

The Rocketry Forum

Help Support The Rocketry Forum:

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

BABAR

Builds Rockets for NASA
TRF Supporter
Joined
Aug 27, 2011
Messages
11,598
Reaction score
6,223
Yes, a rocket that truly flies like it's namesake!
Always foolish to call anything "unique" on this forum, but a few things that set this in the Odd Roc category
Canard Ear Fins (on the NOSE cone!)
Cup Shaped Piston ejection system, wadding-free. I really like this for short stubby rockets that have little room for recovery.
External removable shock cord mount.

Flew it in primer cuz I just couldn't wait. Here's a few starter pics. Also the flight video. Okay, so you can't see the flight, at least you see the launch and the recovery. Gimme a brake, you try video-ing a squirrel!.
Squirrel Raw Top.jpgSquirrel Raw Nose.jpgSquirrel Raw Angle Tail.jpgSquirrel Raw Nose Angle.jpgSquirrel Pad 3.jpgSquirrel Pad 2.jpgSquirrel Pad 1.jpg[video=youtube;lG-6KLSwPmk]https://www.youtube.com/watch?v=lG-6KLSwPmk&feature=youtu.be[/video]
 
I eyeballed the length of the tubing for the rocket to make it look like squirrel.
Yeah, I know, cut first, measure later......
Then I'm looking, and I'm thinking, okay, I have an engine mount, this is a huge nose cone shoulder, not a lot of room for wadding.
I used the BT-60 Body tube and cut a short length, then overlapped a bit to make it a bit smaller so it would slide easily inside the BT-60.
I have discovered the bottoms of Pringles chip cans are cut-able metal, meaning you can cut and shape them with scissors (careful, kiddies, SHARP edges on the cut can.) Cut a circle that would fit just inside the "ring" I made above. Next time I will leave some "tabs" on the sides and fold them up, would make it easier to attach.
Anyway, glued the circle into the bottom of my inner "tube" to create a "cup" shaped piston.
Poked a couple of holes into the middle, so I could attach a shock cord.
Cut a small piece of can metal to "cover" the shock cord (didn't want the shock cord to get fried by the ejection charge.) Glued the metal piece over the shock cord with epoxy.
I put a piece of shock cord through the body of the rocket, through the tail end of the mount, wrapped a couple times around the tube sticking out the back, then poked it back through the tail end of the mount and through the side wall of the rocket. Tied a knot in the loop, pulled the knot into the body of the rocket, and wrapped the extra length around the motor tube sticking out the back, so just a small attachment point on the rocket (this is an external mount, and the shock cord is NOT attached in the "display" configuration.) Therefore there is no INTERNAL attachment that could hinder the inner "piston" from sliding out the front, AND there is no internal attachment at the back that would drape the shock cord in front of the ejection charge.

The DISADVANTAGE is esthetic, you do have an external shock cord, and you DO have to remember to ATTACH it before flight! I use a short length of Kevlar Thread from the elastic to a snap swivel, very easy to quickly attach and remove to the external attachment.
Anyway, it worked pretty well, and leaves PLENTY of room got shock cord, chute, and nose cone. The metal from the pringles can is pretty light, and seemed to shrug off the ejection charge burn pretty will.

I got lucky with my attachment point, when dangling from the shock cord, it is almost horizontal, so the fins don't hit first.
Squirrel Recovery Attitude.jpgRecovery System 05.jpgSquirrel Recovery System 04.jpgSquirrel Recovery System 03.jpgSquirrel Recovery System 02.jpgSquirrel Recovery System 01.jpg
 
First flight was Quest B6-4. I lost my quest ignition system, and am using a new Estes system that I got with a launch set I am still a little nervous about the Quest ignitors going off with a continuity check (anybody know for sure whether the new orange Estes ignition system is Quest Ignitor compatible) Anyway, I did a quick continuity check with an Estes Solar Igniter to make sure batteries good (first launch I've done in almost 4 months.) Good light!
I did 3 flights with Quest igniters. The continuity check did NOT set off the ignitors. Sorry about the shaky video, I like the Estes safety idea of pressing both the continuity key AND the launch button, but it is hard to do that AND hold a camera. Anyway, the slight delay on the video from count down to launch is cuz I was waiting to see if the continuity check would set off the igniter. As said, it didn't.
On the B6-4, the trajectory was up and then away from me, with HUGE barrel rolls. Hence the laughter, to be honest it was EXACTLY what I was hoping for. I would qualify the flight as moderately stable, I think some nose weight is in order (more on that later.) Ejection as a little bit late, although had the trajectory been truly VERTICAL rather than arced over it might have been about right

Encouraged by this, and thinking a shorter delay would be in order, went with a C6-3. The CG was still ahead of the leg and tail fins with this motor. Second flight was TOO close to the namesake, about 30 feet up, then some sky writing, then dropped to ground with ejection a second after landing. Interestingly, parachute got a little bit singed, but I think this is because the chute didn't clear the body tube very far as it was on the ground.
Squirrel broke a foot..... I mean fin. Easily repaired. Even that could have been avoided, I wasn't thinking when I cut the fins and as it turned out the foot fins are parallel with the body tube (always a bad thing.)

Squirrel Tail Singed.jpgSquirrel Piston Post Eject.jpg

The pics show the singe marks on the piston, barely anything there, so I am liking this piston idea for BT-60 and larger bodies low power rockets.
There are some soot marks on the inside of the tail. Not sure how much this is due to the Quest motors versus the design itself. In any case, I think it is just soot, rather than actual burns.
 
Very nice! I like the design.
The ejection cup "piston" looks good and seems to work well.

When I was designing the Pigasus and Little Green Man,
There had to be a reason for the designs to be in the air.
Pigasus was the winged pig. The LGM was a cartoon Martian.

You've got a Flying Squirrel!
(As in Rocky!)
 
anybody know for sure whether the new orange Estes ignition system is Quest Ignitor compatible

Yes, it is definitely compatible. I measured less than 30mA continuity current on a fresh Duracell 9V when I got the first one.

There are some soot marks on the inside of the tail. Not sure how much this is due to the Quest motors versus the design itself. In any case, I think it is just soot, rather than actual burns.
Quest motors are sootier than their Estes counterparts....as well as noisier.

You can, of course, use Estes igniters in Quest motors. The little orange plug for 13mm A3s or a well-used pink B6/C6 plug will work to hold an Estes igniter in a Quest motor. So will a little ball of wadding pushed in with a pencil or the end of a barbecue skewer. That way you can save the Q2G2s for clusters and drag races. :)

Love the squirrel!
 
Last edited:
I'm showing my age but can you say Rocket J Squirrel?
 
Back
Top