[ATM] sonotube for telescope

["David Williams" <dwilliams1128@earthlink.net>]

Hello

I had an idea that I could make an octagonal cross-sectional extruded piece of tube made out of 3/4" plywood.  I got an Amish owned wood working company that built coffins to cut the edges (it was something like 72.5 degrees).

Any way it fit together for a while (I had it screwed together) and then it started to colapse.  It wasn't their fault, it was just too heavy and not strong enough.  So I am looking for a better way to make a telescope tube.

I found a concrete company in Sturgis, MI a city nereby that has 24" diameter by 12'.  My telescope is 20" in diameter (the mirror)  and the f # is F 5 so it is 100".  I could cut it to 8' which is 96".  This seams okay.  Do you think that the wall thickness is allright at 3/16"?  I have a Jeep Cherekee.  Do you think that I could put the 8' section on top and the 4' section inside?

Thank you for your help.

David Williams
dwilliams1128@earthlink.net
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