spacing the bars in the talegate of 16" cell

[fguihen (Fintan)]

im currently working out the dimensions of a tailgate for a 16" mirror.

Im using Kriege's book. In his book, he gives tailgate dimensions for a 15 and 18 inch mirror, but not 16".

for 15" mirror, rung length is 16
for 18" mirror, rung length is 19.75"

its roughly 1.1 inches wider than the mirror in each case ( give or take a few fractions of an inch.

by this reckoning rung length in a tailgate for a 16" mirror comes out at 17.6, which i round up to 17.75 inches. does that sound ok? I mean, is 17.75 wide cell wide enough to cater for a 16" mirror?

[Satchmo]

Isn't the bar spacing dictated solely by the position of the three collimating bolts which in turn support the flotation bars/triangles ?

[fguihen (Fintan)]

you are correct, however width of the cell has nothing to do with the collomation bolts, and is down to the width of the mirror + how much extra you want to add to ensure a nice fit.

my question is not in relation to bar spacings. i have worked this out already. im just unsure if my width of the frame is either too much or too little.

[KGav8r]

When I built my 16" from the book, I can recall facing the same issue as you: There is no example. I can't remember how I arrived at the value, but 17.75 " is what i used (minus 1/32" so it would fit in the box, and it was tight at that!). I took detailed notes when constructing my 'scope so let me know if you need any further information.