Thank you for this, will give it a tryProbably have to do the tube - coupler - centering rings - shroud thing for that transition https://www.ninfinger.org/rockets/US ROCKETS AIR-4 REPORT ACE FUGUE SHROUD METHOD.pdf
You can use a regular shroud rather than the body tube “flower petal” style shown in the .pdf. Payloadbay.com has an online tool for doing transition shrouds.Thank you for this, will give it a try
You could model it up in Openrocket or RockSim and it will create the shroud for youYou can use a regular shroud rather than the body tube “flower petal” style shown in the .pdf. Payloadbay.com has an online tool for doing transition shrouds.
Yes, that works if thick rings are available in that size, otherwise... two rings back-to-back, or other techniques.One wide centering ring, like a thrust ring.
Another one at the end of the smaller tube.
I prefer that to thinner rings, it makes for more gluing surface.
Especially if you sand a bevel into it.
Also more length to secure into the larger tube.
The Apogee BT 80 nosecone actually has molded in cut lines to turn it into a transition for a 24mm or 29mm tube.Does anyone know of a manufacturer of a Bt80 to Bt50 hollow transition? Or is that something a guy could reasonably build?
AS soon as I get home I will sketch it out. It is a pretty big jump, but it is also going to be reinforced with balsa.BT-50 to 80 is a heck of a jump in size! I would guess it would have to be fairly long.
Would you care to show a drawing of what you have in mind?
I agree, that looks complex and a pain to do...plus you have to fill all those little gaps at the bottom of each section...the regular shroud is easier and less work no doubt.You can use a regular shroud rather than the body tube “flower petal” style shown in the .pdf. Payloadbay.com has an online tool for doing transition shrouds.
Here are Tim Van Milligan's comments on the ace fugue method from the Apogee webpage for the US Rockets Micro Sentra SRB:A single piece of card stock is surely easier for a simple transition. For the two slope transitions that the article shows (it only shows nose cones, but obviously one could do transitions that way as well) do you guys think it would be better than fitting two simple cardstock shrouds together?
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And for the curvy shapes, is there any other way. OK, it doesn't have to be from body tube, but cutting the curved mating surfaces into a tube or into cardstock, either way might be about as hard as the other.
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The example worked through uses four panels, and I think one would want to go higher than that to reduce the faceting. The edges, where two panels meet, would wind up lying on the circumscribing circle, so one could build the faces up with filler than sand down to smooth.
The article is © 1984, 1991, 1992, 1997. Nowadays one can 3D print such curvy shapes if one doesn't mind the weight.
I have approximated ogive nose cones and boat tails with multiple straight shrouds. See the Apogee "Peak of Flight" newsletters #409 and #410...A single piece of card stock is surely easier for a simple transition. For the two slope transitions that the article shows (it only shows nose cones, but obviously one could do transitions that way as well) do you guys think it would be better than fitting two simple cardstock shrouds together?
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