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FOUND Estes Polaris (1324) Decal Info

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K'Tesh

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Ok, working on a sim of the Estes Polaris (1324). I received a scan of the instructions from Doug Bertelesen of it, and I've seen the JimZ's page for it (plans.rocketshoppe doesn't have the Polaris). Problem is, Doug didn't have the fins to scan, and JimZ's image of the fins looks like a scan of a bad photocopy of the fin. It gives the length, but is very grainy, and in my opinion not very trustworthy for an accurate sim.

Found that the Polaris used the same fin pattern as the Estes Cold-Powered Convertible kit the Marauder (KL-3). JimZ's doesn't have that, and the info that plans.rocketshoppe has leaves much to be desired.

So, I'm looking for a scan of the fins (BF-L3 (PN 32254) from either the Estes Polaris (1324) or their Marauder (KL-3), along with a ruler for scale. In matrix or out of it is OK. If it's out of the matrix, the ruler is best along the root edge of the fin. Thanks to the Estes Custom Parts Catalog, I know that the fins are 3/32" thick.

I could also use the width/height of the widest blue band of decal for the Polaris (I can scale what JimZ has from that), and while I'm at it, the width/height of the black bars for the Marauder.

Online resources cited:
http://www.spacemodeling.org/jimz/est1324.htm
http://plans.rocketshoppe.com/estes/estKL-3/KL-3.pdf
http://www.spacemodeling.org/jimz/manuals/estp741.pdf
 
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caveduck

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Hey I don't actually think there is anything very bad about the pic in the JimZ package. It's just an old monochrome photo or scan with kinda excessive contrast - note the speckles outside the main image. The outlines seem pretty decent, and if you trust the root edge length (I would, in that era everything was hand drafted and the fundamental dimensions were always a "nice" fraction) I think you'll have the shape within a fractional mm. And the length of the rectangular roll bars next to the "Polaris" is going to be just slightly more than (Pi * .976) or about 3.010". Roll pattern lengths were usually pretty accurate.
 
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K'Tesh

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Caveduck,

Problem with the decals is that when it comes to wraps, there's usually a bit of an overlap, but I don't know how much more of an overlap. If I can get the width of one of the bands, I can scale them all from that (and the overlap won't cause problems with the way OR displays decals because it won't be there).

I've got the sims for both done (less the cold power motor for the Marauder and the decals for the Polaris)... If I can get that info I requested, I'll post the .ork files. I just want to make sure that I'm as accurate as possible.

In the meantime... Here's the Marauder's image

 

caveduck

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This discussion reminded me of something I observed about Estes silkscreened decals. They were printed on big screens with multiple decal sets per panel. As ink is pulled across with the squeegee, the silkscreen can stretch, causing distortion and inconsistent sizes between the various decal sets on the panel. I build a model a while back where the original decals had rectangles and linear features that were noticeably distorted. Later I found a couple of other images of the decal showing varying amounts of distortion on different axes. I ended up actually making very substantial fixes in photoshop (re-drawing many elements) since *none* of the available scans including my own were any good. In the worst case things looked to be as much as 1mm out of line across a 9 or 10" feature. Anyway this imposes a limit on the dimensional accuracy you can get by looking at actual silkscreened decals. Some prints will be better than others, but the only way to remove this error source would be to go upstream to the original artwork layups and use process engineering (bleed distances etc) to arrive at the 'as designed' decal. And that's probably not going to happen except in rare cases.

Anyway the moral of this long soliliquy is that you can't even really trust a decal scan with a high precision ruler in it.
 

K'Tesh

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This discussion reminded me of something I observed about Estes silkscreened decals. They were printed on big screens with multiple decal sets per panel. As ink is pulled across with the squeegee, the silkscreen can stretch, causing distortion and inconsistent sizes between the various decal sets on the panel. I build a model a while back where the original decals had rectangles and linear features that were noticeably distorted. Later I found a couple of other images of the decal showing varying amounts of distortion on different axes. I ended up actually making very substantial fixes in photoshop (re-drawing many elements) since *none* of the available scans including my own were any good. In the worst case things looked to be as much as 1mm out of line across a 9 or 10" feature. Anyway this imposes a limit on the dimensional accuracy you can get by looking at actual silkscreened decals. Some prints will be better than others, but the only way to remove this error source would be to go upstream to the original artwork layups and use process engineering (bleed distances etc) to arrive at the 'as designed' decal. And that's probably not going to happen except in rare cases.

Anyway the moral of this long soliliquy is that you can't even really trust a decal scan with a high precision ruler in it.
Good points...

BTW, the .ork file is up.
 

K'Tesh

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I still need the info on the decals from the Polaris
 

jeffk813

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I'm reading 9.782mm or 0.385" This is based on the length of the stripe being 3.06" long (solving for the circumference of the BT-50). Yes there's usually a little overlap so I'd add maybe a half-mm to that to make up.
 

K'Tesh

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Finally got my own sample of the Estes Polaris (1324). So, I was able to scan the decals for myself finally. The big problem was with the fact that the image of the decals on JimZ's site was not an original scan, but something that was manipulated, and I wanted to be as close to the blue as I could get.



The .ork file is now posted in my OpenRocket Files thread.

 
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