Re: [ATM] Two Stage Truss

["Arjan te Marvelde" <arjan.te.marvelde@hetnet.nl>]

Jay Kirkland wrote:
<<    I'm even startled by how much 8 pairs of aluminum plugs for joining
sections of tube would weigh. At 2" long for each of the sixteen 1 1/4"
plugs, with 3/8" stainless threaded rod running thru, the total there is
about 5 pounds! Imagine hanging a 5 pound weight 1/3 or 1/2 way between
your balance point and eyepiece. Your scope would not thank you.
    But I keep thinking that there has to be a more elegant solution to
long tubes than buying a roof rack.
    Jay >>

A better way is to put the middle ring AT the balance point of the OTA. Then
the weight doesn't matter for balancing, only the fork/rocker box should be
able to support it.

As Tom Krajci mentioned, strictly the attachment of the truss to the ring
can be flexible. On the other hand, when clamped in rigidly, they can have
smaller diameter, and thus be lighter.

When you also want to be able to take the OTA apart, it may be an idea to
slice the center ring, but glue the truss tubes to mirror box/1st center
ring and 2nd center ring/secondary ring. You only need 6 truss tubes, which
can be relatively light tubes.

Tom K.: Did you also model this arrangement? Can your model also do clamped
tubes?

Arjan te Marvelde
N 52:13'03"  E 5:09'10"



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