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Post by eamonnpkeyes on Dec 10, 2006 12:47:26 GMT
I got a chance to get the new scope out last night, and got about five minutes to use it before the clouds came roaring in instantly. One possible problem I noticed is that of shroud droop over the wider areas between the truss rods. In this case the fabric can slightly droop so it's into the edges of the light path. There is a shroud which has a couple of rigid rings sewn in to prevent this, but it's only available from the US and they're looking ridiculous amounts of money to ship it. So...anyone got any ideas? I've got a couple involving Velcro, but I'd like to see if ant one of you people can suggest a better fix...the astronomical community is notorious for home-built fixes.
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Post by NeilP on Dec 10, 2006 14:28:51 GMT
Any way you could put and old belt or something round the trusses near the bottom maybe stop the shroud sagging in so much
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Post by eamonnpkeyes on Dec 10, 2006 14:51:36 GMT
Two ideas I have...first, vecro around a couple of points on all three trusses. Then two wraparound belts of velcro to go around the points to stop the sag. A possibly better idea...needing refinement, is for slats of venetian blinds. If they are wrapped into a circle they push outwards to try to go back to their straight shape. If I can somehow incorporate them into the inside of the shroud they'll do the job. However, as they're white they'll need sprayed matt black, and the shrouds are somewhat thin, so fastening them directly might be problematic. Maybe a mix of the two above....velcroing circled slats might be the answer, but maybe a bit awkward in darkness in the field.
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Post by markdj on Dec 10, 2006 17:05:01 GMT
Which shroud did you get? I have seen an AstroZap one in action and it didn't seem to be an issue. Have you tried tightening the velcro at each end?
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Post by kryss on Dec 10, 2006 17:13:45 GMT
I think you need some type of elastication ie keep it under tension. I also have a 10m roll of blackout matieral that i bought off ebay your welcome to a suitable length.Its white but that shouldnt matter if it blocks ambient light.
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Post by eamonnpkeyes on Dec 11, 2006 0:18:50 GMT
The american one is the Astrozap one...with the built in hoops to stop shroud droop. I think I've the solution...a black 15" diameter plastic mixing bucket. I'm cutting it into two or three inch strips around that hold their circular integrity, so they act as rings, and putting them inside the shroud, using a heavy duty stapler to hold it all together..three of these rings will do the job. Next week I'll be building a bulldozer from Weetabix boxes and elastic bands.
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Post by Phil on Dec 14, 2006 14:43:10 GMT
Just a thought... you could use welding rods looped round... should be a fair bit of tension there?
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Post by Veronica on Dec 14, 2006 14:56:15 GMT
Sorry, but have I accidently logged in to the A Team Fan Club forum? Hope ya get it sorted Eamonn!
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Post by eamonnpkeyes on Dec 14, 2006 15:12:43 GMT
Got it done..not the most cosmetic of solutions, but it worked. I designed a ring particle accelerator that fires atoms in a coil kept suspended in a magnetic field until they form a totally opaque screen, thus shutting off light. However, the accelerator weighs three tons, and it needs 9 gigawatts of electricity to operate, so Killylane might be a problem. ;D
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Post by markdj on Dec 14, 2006 15:56:25 GMT
LOL LOL.
I think what's worse is that I actually would love to see that going!
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Post by NeilP on Dec 14, 2006 16:22:28 GMT
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Post by eamonnpkeyes on Dec 14, 2006 17:05:38 GMT
Sad...innit? The bucket option worked. Cut the top off the three buckets..15" diameter exactly, stapled them inside the shroud at 9" intervals, and slid them down over the trusses..they keep the shroud hooped out nicely, no sagging at all. Just don't look at it in daylight, that's all.
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Post by Phil on Dec 14, 2006 17:10:08 GMT
Some people could say that about you Eamonn
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Post by eamonnpkeyes on Dec 15, 2006 0:53:42 GMT
yes...but so few actually do.....!
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Post by markdj on Dec 23, 2006 2:58:01 GMT
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