Time for another scratch build. I can't take complete credit for this design as it is something that I recall seeing at a launch many many years ago before I left rocketry and it stuck in my head as something I wanted to build. I've not been able to find anything on the market that looks like it currently so I don't know where to give credit for the design.
For my build I'll be using the following items.
- Fins and lug standoff cut from 3mm birch ply.
- Estes PSII 2.0 inch body tube cut to 10 inches for the lower tube.
- Estes PSII 2.5 inch body tube cut to 1 inch for the upper ring.
- Estes PSII 2.5 inch nose cone.
- Estes PSII 2.0 to 2.5 inch transition.
- BT50 motor tube cut to 3.75 inches.
- BT50 centering ring for a motor block.
- Centering rings. Ply for the upper, cardboard for the lower.
- 1/4 inch launch lug.
- 500# Kevlar shock cord.
- 3mm bulkhead and screw eye (not shown).
Unlike most builds, I'm going to start with the nosecone on this build. For this step we will need the nose cone and the 2.5" ring. The PSII nosecone has had the shoulder cut down to 1/2 inch.
Since this connection is cardboard to plastic, i'm using BSI epoxy for the bond.
Epoxy was spread on the inside of the ring as well as the outside of the nosecone shoulder. The outside of the shoulder has been sanded with 100 grit to give the surface some texture.
The pieces were then connected and the excess epoxy was cleaned up with rubbing alcohol.
For my build I'll be using the following items.
- Fins and lug standoff cut from 3mm birch ply.
- Estes PSII 2.0 inch body tube cut to 10 inches for the lower tube.
- Estes PSII 2.5 inch body tube cut to 1 inch for the upper ring.
- Estes PSII 2.5 inch nose cone.
- Estes PSII 2.0 to 2.5 inch transition.
- BT50 motor tube cut to 3.75 inches.
- BT50 centering ring for a motor block.
- Centering rings. Ply for the upper, cardboard for the lower.
- 1/4 inch launch lug.
- 500# Kevlar shock cord.
- 3mm bulkhead and screw eye (not shown).
Unlike most builds, I'm going to start with the nosecone on this build. For this step we will need the nose cone and the 2.5" ring. The PSII nosecone has had the shoulder cut down to 1/2 inch.
Since this connection is cardboard to plastic, i'm using BSI epoxy for the bond.
Epoxy was spread on the inside of the ring as well as the outside of the nosecone shoulder. The outside of the shoulder has been sanded with 100 grit to give the surface some texture.
The pieces were then connected and the excess epoxy was cleaned up with rubbing alcohol.