I've got the itch to build a three fin BT-80 based cluster rocket (cloning a certain OOP "obese" model) with either 3 x 18mm or 4 x 18mm mounts.
I'd like to do through the wall fins like the original, but I'm having a hard time figuring out the best way to attach them to the motor mount inside since the motor tubes will be an "irregular" mounting surface.
In theory, I guess I could probably make templates out of cardboard and custom make each fin's TTW tab extend to a good spot on the motor mounts although each one tab would probably be a different length and I'd be worried that the joint might not be the best on some of them. I did something like this on my Super Goblin upscale, but that only had 2 x 24mm mounts and four fins and was easier to do.
The other idea would be to mount the engines inside a smaller diameter tube (BT-70?) then try to center that inside the BT-80, thereby making a regular mounting surface for the fins. This would add some weight to the motor mount but would allow for nearly identical fins and solid attachment.
Any thoughts?
I'd like to do through the wall fins like the original, but I'm having a hard time figuring out the best way to attach them to the motor mount inside since the motor tubes will be an "irregular" mounting surface.
In theory, I guess I could probably make templates out of cardboard and custom make each fin's TTW tab extend to a good spot on the motor mounts although each one tab would probably be a different length and I'd be worried that the joint might not be the best on some of them. I did something like this on my Super Goblin upscale, but that only had 2 x 24mm mounts and four fins and was easier to do.
The other idea would be to mount the engines inside a smaller diameter tube (BT-70?) then try to center that inside the BT-80, thereby making a regular mounting surface for the fins. This would add some weight to the motor mount but would allow for nearly identical fins and solid attachment.
Any thoughts?