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Ukastronomer
21-06-2019, 12:17 AM
Just seen this

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https://www.ebay.co.uk/itm/Telescope-Meade-10-inch-Dobsonian/223552784984?ssPageName=STRK%3AMEBI DX%3AIT&_trksid=p2060353.m1438.l2649


Who would want it

Merlin66
21-06-2019, 02:03 AM
Many of the early popular Dobsonian telescopes had cardboard tubes - Coulter etc. Not unusual.

bojan
21-06-2019, 07:47 AM
And cardboard is pretty good material actually.
If treated properly (painted and/or impregnated with resin) it can last a very long time.
The most important thing is mirror..

Wavytone
21-06-2019, 08:39 AM
Long f-ratio full-tube newtonians can be extremely good - don’t knock it. Having made one with a cardboard tube, it’s sort of ok but won’t last forever if used often. It must be sealed - every cut, every hole - because dew and humidity will get in. It swells and turns very soft with moisture.

Mine was used very often and it was deteriorating badly after 5 years.

theodog
21-06-2019, 09:10 AM
Me. Still have my DS10 tube from last century.:thumbsup:

inline_online
21-06-2019, 10:41 AM
My second scope was the Meade Starfinder 10. It was a 10" Newtonian, made from the cardboard 'Sonotube' and was a very very good scope.
I never had any issues with the tube material, even on the nights when it was 100% drenched with dew.
I spent a lot of time also using the Meade DS-16 which was made from the same material.

To answer your question, "Why would want it?" I'd take another in a heartbeat. Wouldn't get rid of the Tak for it though:lol:

alocky
22-06-2019, 02:15 PM
And another happy owner. I still have a sonotube 10"f4.5 Meade starfinder. The mirror is a diffraction limited optic, the collimation holds enough for some pretty tight astrophotos, and I used the thing visually for well over a decade without any issues with the tube. I moved the mirror up the tube, put in an oversized secondary, reamed out the focuser hole for a larger low profile 2", and never felt bad doing it :-).
cheers,
Andrew.

Ukastronomer
22-06-2019, 05:42 PM
I guess then it isn't just a strong card, is is specially treated

RAJAH235
22-06-2019, 10:51 PM
A FWIW...
I also had a MEADE 10" Dob.
As stated, it's called "Sonotube" & is very resilient when treated to resist ingress of moisture.
I never had any problems with it for many, many years.
The main mirror was made of "PYREX", not just the "stuff" they turn out now.
That mirror was originally worth around $900.00 to replace, or so I believe.

Even withstood being under water when the caravan park got flooded & the t'scope decided it needed to "float around" a bit.

Only thing/s that needed cleaning were all my eyepieces & filters.
No water ever got into the tube & it stayed perfectly dry inside.

Pity that I got rid of it so soon though, as I had "tuned it to perfection."
Could move it in any direction with just your little finger.

PLUS...It was always as dry as the proverbial, even on heavy dew nights when everyone elses was dripping wet.

I just wish I had the room for a larger MEADE Dobsonian scope.
Maybe....one day?

raymo
23-06-2019, 12:27 AM
I'll come out of retirement long enough to say that a friend of mine had
a Coulter 17.5" about 35 yrs ago,[also Sonotube], had a very nice mirror,
and gave terrific lunar views at 750x on nights of good seeing. [which was most nights, as we averaged 300 or so cloudless nights per year] A friend of
his had the 29", but I never had the good fortune to observe with it.
raymo