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JimmyH155
26-06-2006, 11:21 AM
Well we went up the mountain this week end- saw not many stars - only 1 hour in 3 days. Anyway, on the way up we did 220 klm all on bitumen roads, and when I erected the scope, it was in good collimation despite all my fears to the contrary.
We returned a different route which resulted in traversing no more than 10 klm of rather corrugated gravel road. I drove in such a way as to minimise the vibrations.....
Back home, when unpacking the Lightbridge, when I came to the mirror can, I lifted it out of the boot of the car and heard little tinkling sounds.... these were caused by all 3 of the primary adjusting screws - including their springs - dancing off into the spare tyre compartment. The mirror was completely loose, and only attached to anything by the wire for the fan!

I have to agree with you guys who advised to put stronger springs in. The Meade supplied ones are totally inadequate. They advertise the Lightbridge as easy to carry to remote sites, and fail to make them rugged enough to survive 10 klm of gravel roads. I am going to fit much stronger springs and also have a little look at redesign - the whole attachment system looks flimsy.
So all you people about to travel to that dream dark site in the bush, :D BEWARE,:sadeyes: and pack your scope very very carefully.
I have now to do a complete collimation job - something I was dreading, but now forced upon me!! Oh well, it's all part of the rich tapestry of life.....;)

ving
26-06-2006, 11:25 AM
gee!!! at least your mirror is ok... it is ok isnt it?
:eek:

janoskiss
26-06-2006, 11:40 AM
AS you have found out, the mirror springs on the collimation bolts on the 12" GS Dobs (lightbridge included) are too weak. Unless you replace them, you have to use the three locking bolts as well as the three collimation bolts (nice and tight) so you get a push-pull arrangement. That's the way I used them. Makes collimation a bit more tedious (need screwdriver because everything is very tight), but it holds the mirror cell very firmly.

Screws holding mirror clamps will tend to come lose as well and will likely scratch your mirror, especially if you have loosened them to take pressure off mirror as recommended. You need to apply some Loctite to the threads for transportation.

JimmyH155
26-06-2006, 11:53 AM
Yes, fortunately the mirror seems to be ok, and last night I managed to get it onto the workbench and put the screws and springs back in. But lunch time today, I'm off to the hardware store to look for some springs....:)

astronut
26-06-2006, 01:09 PM
Hi Jimmy, Sorry to hear of your experience, I hope your mirror came through unscathed.
I transported my LB12" down to our clubs dark sky site on the weekend.
Over about 4km of rough road. I unpacked the scope and collimation was only a slight tweak of one of the primary knobs.
I recommend that you change the primary springs immediatly.
It will make a world of difference and because they are stiffer you can do away with the locking pins.
Whist you're at it change the Primary and secondary screws, the difference is light years better, they are hand operated, NO TOOLS NEEDED. Hope this helps, John.:thumbsup: