(BAR-38) Mach Buster

Here's a scratch built Hot Rod Rocket made to break the speed of sound.

Main Body is BT-52H, Fin Can is BT/C-55, Nose Cone is custom turned from pine and the Rear Fins are plywood.

Power is via a G80T-10 AeroTech composite motor.

The ejection is from the rear.

The spool is made from a 3/8" dia. solid wooden dowel that is attached to the Nose Cone via a Kevlar Shock Cord. The motor has a lanyard epoxied to the hex on the ejection end of the rocket, which is also attached to the spool. At ejection the force pushes the motor out of the rocket, and the lanyard pulls the spool from the rocket.​

 

 2024-10-05 CAD Drawings, Rev 00

Lakeroadster's Fin Alignment Fixture

Inspired by this thread Homemade Fin Alignment Guide I decided to take a crack at making a fin alignment guide.

My design is basically the same as The Rocketry Forum's @qquake2k with the exception of being double sided. One Side is for BT-60 thru T-400 tubes, the other is for BT-20 thru BT-55 tubes.

Here's the CAD drawings:

 2024-09-16

Armed with the drawings I headed out to the barn to make some sawdust. I changed the design a bit, making 4 longer legs for the base.

I mocked up the parts for a visual representation... once the glue dries and I get a couple carriage bolts, I'll post up some more photos.

2024-09-17

Here's the finished jig / fixture.

I ended up using 3/8" dia. x 3-1/2" Carriage Bolts, washers and wing nuts. The wing nuts were $2.48 each?

For the mock up photos l used a piece of BT-60 and a left over plywood fin from my Spad Ace build, and that's a BT-50H for the smaller tube.