I am building a clone using the instructions and templates on JimZ's site (apparently the only source). Anyway, there is a scaling issue with the template scan. The instructions state that the body tube marking guide is 1 1/32 inches wide (1.031") but the template scan is actually 1.12" inches wide. It is also too long to fit the tube properly, but this dimension is incorrect by a different factor than is the width.

There are several other problems with the fin templates. For example, the matching angle between the fin and the fairing is way off and if you add up the length of the fin root and the fairing root they should equal 12.7" (the length of the body tube), minus 1 1/32". They don't.

I drew up some "corrected" patterns for this model and attached a PDF file. These fins and fairings have lengths that fit the body tube and I redrew the heatsinks so the RT-70 will fit properly. There's also a redrawn marking guide that is 1 1/32 inch high.

The fin was changed a bit as well, it is now an accurate 30-30-120 triangle.

Attached Files

starlight patterns.pdf (21.5 KB, 211 views)

The Astron Starlight is one really cool looking rocket, but I have to admit that I was
"scared away" from buying it during my early years in the hobby as I thought it had too much balsa surfaces to deal with comfortably.

But thinking now, I'd like to go ahead and build a clone of this model. Thanks for bringing
this subject up!

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Dave, NAR # 21853 SR.

Danke. I'll get these up on YORP next week.

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Scott D. Hansen
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WOOSH NAR Section #558

I made the fins out of basswood instead of balsa and they didn't turn out too heavy. I was worried that with all the fins it might be a bit heavy with bass but it was OK. Basswood is MUCH easier to fill and finish than is balsa.

This brings up another subject, namely how much I dislike filling balsa. Carl and Semroc have really nice laser-cut fins (I LOVE laser cut fins!) but they are all balsa. I wish Semroc would give you a choice of either material and just charge you the difference. I would gladly pay more to get basswod fins rather than balsa. I know BMS might do it but they only accept RockSim files which is a horrible program to try and use for drawing fins (IMHO).

Thanks for the information on the Astron Starlight ! I just completed my clone using Semroc parts and JimZ's plans this past weekend ( see pict ). She’ll be ready for paint ( white & red ) on Saturday. I’m going to build second one using the new template you provided and paint it in the original colors of silver & transparent blue. Thanks again for the info ! This was my favorite rocket as a kid ….despite the ocean of balsa wood !

Attached Thumbnails

 

The Starlight would be a great model for the BMS "Kit of the Month".

Laser-cut parts. I like it!

Bob

I'm thinking the same.....

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Dave, NAR # 21853 SR.

Yeah....but is Bill?

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Don
NAR 53455
"Carpe Diem"

He probably has a lot of preparation to do for NARAM, so we should give him a couple of
months. Hey, speaking of Bill of BMS, is he a member of this forum? I know he posts quite
a bit over at TRF, but I don't recall seeing him here. Maybe we should recruit him over....

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Dave, NAR # 21853 SR.