New scratch build: Penumbra

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I thought about a tail cone, but decided not to use one for a couple of reasons. One is cost. It would cost $30 with shipping to get a transition from LOC.
I could turn one, but it would cost about the same to get a basswood or balsa block big enough. The second reason is the weight. Even with a relatively light plastic tail cone, it would affect the stability. Right now I can get away with 4oz of nose weight. With a tail cone, that would increase to 8oz or more. The extra weight would seriously affect the altitude. So no tail cone.

As for color, I have to paint the forward body tube black because the eclipse decal will have a black background. Right now, I like black and a dark red. Since I prefer satin finish paint, I'll have to see what colors are available. There aren't as many satin colors as there are gloss.

3D print one. :) I know a guy.
 
I appreciate the offer, but a 3D printed tail cone would still add weight.
 
No way. I hate paper and card stock transitions. I don't have the dexterity or patience.
 
I epoxied blocks to the centering rings for the rail buttons and tee nuts.

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I cut out and sized the baffle plate and centering ring that will go inside the coupler. I've had problems in the past with chipping when I drilled the vent holes. So I tried something different this time. After marking the hole positions with a center punch, I drilled all the way through them with a small bit. Then I drilled from both sides with a 3/8" Forstner bit. I got very clean holes this way.

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They cut fairly clean, but the issue is sizing them to fit. I choose the closest size, then turn the centering rings or bulkheads down to fit inside the body tube or coupler.
 
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