Sunday, October 12, 2025

(BAR-55) Defender-HVY .... A Scratch Build

Here's a modifiedTRF Member @neil_w design that he graciously handed to me in his Half Baked Design thread.

​I shortened the body tube, added some X-Wing style laser cannons and generally moved things around a bit, but it's still pretty true to Neils design.​
This one is a rear eject, with a 29mm composite motor and a 24" Nylon parachute.​
 


2025-10-12 Kind of digging this partial rear ring fin option....
 
 

2025-10-13 Build Day 01,


3" Tube Fin R&D and Gluing Up Nose Cone Blanks

Doing a bit of R&D on the 3" Tube Fin. I had a 3" shipping tube in the barn and cut off a 3" long piece of it. Chucked it into the lathe and sanded the O.D. and I.D., which proved to be very "fly away". By that I mean the wraps of paper the tube is made from de-laminated easily. I decided to coat the inside and outside with wood glue and then sand the part. I think it's going to work pretty well.​
The nose cone blanks were pretty straight forward. Used some scrap 2X material and glued them together to form a 3" x 3" square. I'll turn the Nose Cone from this glued blank.​
 


 3" Ring and Nose Cone Buck

The wood glue did the trick! Some cwf and the ring will be done. 
 


2025-10-14 Preliminary Drawing Rev 00 and the CAD Model
 



 

 2025-10-15 Drawing Set Rev 01
 










2025-10-17 Ring Fin Fixture

The ring segments are 6-3/4" o.d. x 6-1/2" i.d. x 2" wide. A little over 90 degree each segment.​
Fixture
I laid out the ring fin on a scrap piece of 1" thick stair step. Then using my scroll saw the 6-3/4" o.d. was cut. Then chucked the inner circle in the lathe and cut it to 6-1/2" o.d.​
I then cut the inside ring and the exterior ring into 2 pieces on my table saw. Then glued the pieces to form half circle fixtures that are 2" thick.​
 








 2025-10-18 Outer Ring Segment #1

Cut the 1/32" Basswood into (4) 2" x 6" strips, added glue to them and clamped them in the fixture.​
I was surprised at how easy it was to form the ring, but that's likely due to using 1/32" Basswood.​
Basswood was formed "The Hard Way" meaning the grain wraps around the ring, not longitudinally.​
We'll see how it comes out tomorrow when I pull it from the mold.​
 


 Drawing Set Rev 02:  
Revised Vert Stabilizer to match the OpenRocket Simulation Model
 










2025-10-19 Outer Ring Segment #1: Day 2

Pulled the Ring Segment from the fixture and sanded the width to size. I'd call this one a success.​
Started gluing up the matching Ring Segment.​
 







 Outer Ring Segment #2
 
 
2025-10-20 Nose Cone, Tail Cone and Wings

Turned the Nose Cone and Tail Cones. I went to sand the inside of the Tail Cone and it experienced a SUB: Sudden Unscheduled Breakage. No worries, it glues to the motor spool tube, should be able to just glue it all back together.​
Cut, sanded and routed the Wings, made from 1/4" plywood. They're still rough and will need some more adjustments to fit the 3" Tube Fin.​
 



 
2025-10-20 Tail Cone Rework



2025-10-21 Attaching the Wings

Decided to use my Fin Alignment Fixture since the Fins Wings are spaced at 180 degrees​



2025-10-22 Tube CWF and Installation
Applied some CWF to the Tube Fin and then when it was dry sanded it down on the wood lathe.​... then began wood gluing it to the wings.​
  






2025-10-24 Vertical Stabilizers and Their Bases

Cut the Vertical Stabilizers and sanded them to shape.​
Glued the Vertical Stabilizer Bases to the rocket.​
 





2025-10-25 Attaching Rear Ring Fin Segments

These turned out to be quite tricky to attach:​
I fixtured up the rocket so it was level,​
shimmed under the Ring Segments,​
glued the segments to the wings,​
then adjusted the gap between the two segments so it was the same, upper and lower.​
Not using a lot of wood glue here, just enough to hold them in place. Once the (4) Vertical Stabilizers are glued, then I'll do fillets on all the Segment attachments.​




2025-10-25 Vertical Stabilizers and Photo Shoot

Got all (4) of the Vertical Stabilizers installed, and did a photo chute.​