Construction started!!! and another rocker box que

After many months of planning and accumulating many of the parts I've finally started construction of my first truss dob. I made the first cuts of the beautiful 4x8 1/2" european birth plywood and have started the UTA rings. It's going to be a Kriege style with 14.5" F4.3 Ed Stevens primary. 8)

I'm thinking ahead and I have a rocker box question. The book says to make the rocker sides 1" thick. I have both 1/2" and 3/4" plywood. Would making the rocker sides 1 1/4" thick cause any problems other than making it heavier? The book says to make the side bearings 1 1/8" thick.

Thanks,

Jim,
The 1.25" will be great, a little heavier, but very stable. You could cut some decorative holes if you wish to lose a little weight. This 12.5" had 1.25" sides and there were cut outs to lighten it.

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Hi Jim

Where did you pick up the birch plywood locally? Home Depot or Lowe's? Or did you go to a local lumber yard?

Also the truss poles, who did you end up with as a supplier?

Did you look at any pre-fab parts from Astrosystems?

I'll probably see you guys at the GLSG this year.

Thanks,
Tom

Jim,
I know this isn't popular info, but I just rebuilt my old 16" f/5 into a much lighter, smaller dob. I took the 3/4" mirror box sides and replaced them with 1/2" baltic birch (11 ply). The rocker box was originally 1" thick sides and bottom. The new one is 5/8" thick (also 11 ply baltic birch) sides and bottom. They also have lightening holes in them, sides and bottom. I got a little carried away on the lightening and the rocker flexed just a bit too much for me, so I closed up the holes on the inside with some 1/16" 3 ply aircraft ply and finished it out with stain and complementing colors. The scope is EVERY bit as stable as it was before rebuild, and is 1 sq foot less large (floor footprint) and is 50 pounds lighter. This is about at the limit of stable as I found out, but when built well out of good materials, there is no reason to build it any heavier unless you just like weight lifting. I figure a lighter scope will get used more, and a scope that doesn't get used is nearly worthless to me.
My criteria for stable is to be able to move the scope while viewing without vibration, much less any after the scope stops, no vibration while focusing, and only about 1 to 1.5 seconds of vibration after a sound whack to the upper cage. You can find details at this site:

http://wkaa.net/gallery/index.php

The Kriege book way is very overbuilt in my opinion.

David Paessler
West Kentucky Amateur Astronomers