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alea iacta est..or the silicone has been squeezed

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#1 Noisykids

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Posted 13 November 2012 - 05:46 PM

i wimped out on the full dress version of the kriege/berry mirror cell. i had the whole thing done, but didn't care for it much.

so i took the cutout from the mirror box, cut multiple holes in it and screwed it to the aluminum bars on the collimating bolts.

there was plenty of play as far as wobble goes so i'm not nervous about collimating.

then i glued the mirror to it with silicone, three big blobs into some countersunk holes with nails for spacers in between.

in the chapter on the 10" dob in berry's book he shows some vertical dowels with holes drilled through them and more silicone is squeezed into those to support the edge of the mirror.

this contraption lacks that feature and i'm wondering if i'm going to miss that. it would be easy enough to add.

i solved all the balance problems with the smaller weight and the counterweight shaft from my orion eq 1 and i installed a brake on one side of the rocker box.

once the silicone has set i ought to be able to reassemble this thing and see if it works.

#2 Noisykids

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Posted 14 November 2012 - 06:00 PM

this ought to confirm it for members of this nice little online community....i'm an idiot., just got gorilla glue on the primary.

#3 Mirzam

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Posted 14 November 2012 - 06:38 PM

Just don't drop the primary while cleaning it.

How much glue are we talking about?

JimC

#4 Noisykids

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Posted 14 November 2012 - 06:42 PM

tiny amount on the edge isn't going to affect anything. still, who needs it? what a maroon.....

#5 cheapersleeper

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Posted 14 November 2012 - 09:51 PM

tiny amount on the edge isn't going to affect anything. still, who needs it? what a maroon.....


...happens more often than you would think. :roflmao:

Regards,
Brad

#6 glennnnnnn

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Posted 15 November 2012 - 10:17 AM

After a number of accidents like that in so many different projects I normally take extraordinary precautions, like covering anything delicate like an exposed mirror with an impact-deflecting surface.
Gorilla glue will come off, eventually.
It could have been worse!

EDIT: I'm not superstitious, but I've heard that if you break an Astronomical Mirror its 700 years bad luck!!!

#7 Noisykids

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Posted 15 November 2012 - 12:17 PM

i just reassembled the whole thing and brought it upstairs. all i have to do is pop in the secondary and i'm good to go, hopefully. but the day is crawling on and i have to get cleaned up and leave for a second shift which i normally don't ever have to work except at the holidays.
i was installing the bottom side supports which were originally the eccentric dowels but i faced them off flat, used the gorilla glue to attach a small square piece of wood and then stuck an adhesive backed felt furniture thing to it. i set the whole thing onto the bolt, and missed. the wet glue touched the circumference of the mirror.

#8 starman345

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Posted 15 November 2012 - 12:32 PM

No matter how careful you are it seems things happen when the mirror is exposed. I put on my primary center dot yesterday, sweated bullets trying to get it exactly in the center without getting fingerprints on the thing. I was lucky this time, no disasters

#9 glennnnnnn

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Posted 15 November 2012 - 12:59 PM

If I need to get close enough to touch the mirror, I plan how I'm going to do it. For the center-dot target it gets masked off with a disk of heavy paper and only the smallest-possible diameter in the center is open. Easy to do with a compass. If its the same diameter as your mirror, you have measured the center in advance and only need to stick down the target.
If I don't do it like this, I KNOW SOMETHING BAD WILL HAPPEN!!!

#10 Noisykids

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Posted 19 November 2012 - 09:55 AM

i got the thing collimated, as it turned out a very easy process,hauled it out onto the deck and struggled to find the moon. no finder attached yet, but the telrad is ready. the sky in mass was not fabulous last night, and it was just after sundown so not a lot of contrast, but the moon looked great.
i randomly pushed the scope to look somewhere in the middle of the triangle, and i kid you not, albireo popped up in the eyepiece. i had a 40mm eyepiece in and the double was easily visible, and i don't think that happens with my eon 80mm.
this thing is short. i have to put it on a piece of plywood on a milk crate so i can comfortably reach the eyepiece. the moon was low enough that without the extra height i had to kneel down and still look up into the focuser.
i've got some more work to do, but it works and that's a start.






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