A couple of weeks back I picked up a nice used Estes Fat Boy from another member with the sole intention of rebuilding it to fly on 29mm motors.
The rocket was in nice shape overall and a good candidate for the project. Due to the altitude I'm planning to use streamer recovery so I'll be beefing up parts along the way to survive the flight and the landing.
Here the rocket I started with. It was a nicely built but well used Fat Boy.
First step came disassembly. With a little sanding of the paint and scoring the glue with a hobby knife, hot water was applied to the glue joints and the rocket pretty much just pulled apart.
Here are the parts we're going to use to rebuild.
- Stock nose cone. The bottom has been removed as I'm going to need all of the room I can get inside the body tube for recovery gear.
- Bulk head for the nose cone with a couple of piece of scrap use use as backers.
- Rear Centering ring made from card stock.
- Upper ring made of 1/8" plywood with a piece of scrap for a backer for the chock cord attachment point.
- Stock BT80 body tube.
- BT80 Coupler cut 1 inch shorter than the body tube to allow room for the nose cone shoulder.
- Original Balsa fins and the some file folder material cut to shape to paper the fins.
- 29mm motor retainer.
- 29mm motor tube.
Assembly began with inserting the coupler into the tube. I used epoxy for this as the fin slots were already cut and I wanted the ability to move the couple to align the slots with the tube. Epoxy was spread inside the tube and on the outside of the coupler.
With the main body curing I began work on the motor mount. The areas where the rings, motor retainer and fins will attached have all been sanded to allow the epoxy to penetrate the materials.
The motor block was inserted into the motor tube then the upper ring was attached. After letting that cure, I added a piece of 500# Kevlar for the attachment point for the recovery system.
After letting everything cure for a day I inserted the motor mount into the body tube and set that aside to dry for a day.
I'm working on papering the fins today so we'll get those attached in the next update.
The rocket was in nice shape overall and a good candidate for the project. Due to the altitude I'm planning to use streamer recovery so I'll be beefing up parts along the way to survive the flight and the landing.
Here the rocket I started with. It was a nicely built but well used Fat Boy.
First step came disassembly. With a little sanding of the paint and scoring the glue with a hobby knife, hot water was applied to the glue joints and the rocket pretty much just pulled apart.
Here are the parts we're going to use to rebuild.
- Stock nose cone. The bottom has been removed as I'm going to need all of the room I can get inside the body tube for recovery gear.
- Bulk head for the nose cone with a couple of piece of scrap use use as backers.
- Rear Centering ring made from card stock.
- Upper ring made of 1/8" plywood with a piece of scrap for a backer for the chock cord attachment point.
- Stock BT80 body tube.
- BT80 Coupler cut 1 inch shorter than the body tube to allow room for the nose cone shoulder.
- Original Balsa fins and the some file folder material cut to shape to paper the fins.
- 29mm motor retainer.
- 29mm motor tube.
Assembly began with inserting the coupler into the tube. I used epoxy for this as the fin slots were already cut and I wanted the ability to move the couple to align the slots with the tube. Epoxy was spread inside the tube and on the outside of the coupler.
With the main body curing I began work on the motor mount. The areas where the rings, motor retainer and fins will attached have all been sanded to allow the epoxy to penetrate the materials.
The motor block was inserted into the motor tube then the upper ring was attached. After letting that cure, I added a piece of 500# Kevlar for the attachment point for the recovery system.
After letting everything cure for a day I inserted the motor mount into the body tube and set that aside to dry for a day.
I'm working on papering the fins today so we'll get those attached in the next update.