Re: [ATM] Strip planked telescope tube

[George Anderson <tillerman1@videotron.ca>]

I have made two scopes using a similar method for the wood (one from
pine the other from cherry). The exception being that the circular disks
were replaced with rings were made from 1/2" wood and the inside of the
rings were cut with a taper with on wood lathe. These were left in the
tube after assembly and provided baffling.
I made up a jig which held the rings in place while the strips were
glued on one at a time (glued to both the rings and the previous strip.
each strip was glued and clamped for two hours before the clamps were
removed and the next strip glued into place. It took three or four
evenings to assemble the tube and afterwards just a couple of hours of
sanding (32 strips for the 8" cherry tube) to get a nice round tube. 8
coats of hand rubbed oil based varathene were used on the outside
finish. The tube is light weight and doesn't flex at all. The pine tube
was even lighter and probably just as sturdy.

George Anderson
Montreal Canada

Clear skies and good health

Gilbert Gagne wrote:
> 
> This is a great idea.
> I built such a tube for a 4 1/2 inch f/10 using 3/16" pine cut 3/4" wide
> on a table saw. Assemble on several circular disks mounted on a length
> of pipe. Cover the disks with something to keep the glue from them. I
> also cut the disks in half and taped the pieces together to make removal
> easier. My tube was coverred with a single layer of  fiberglass cloth
> and sprayed flat black on the inside. Using the same technique for
> patching rust holes on my cars, I spread the fiberglass cloth on
> aluminum foil and worked the epoxy resin into it until it became
> translucent using only the barest minimum of resin. You can then lift
> the alum foil from the back and transfer to the tube without getting
> resin on your hands. With the tube now coverred with alum foil, you can
> smooth the resin/cloth with your hands. The alum foil comes off easily
> after the resin has cured. My tube has a beautiful yellow-orange glow
> from the wood and resin with the wood grain clearly visible.
> 
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