need help for lighter weight tube making(closed)

Wanna make a scope? Or better still, grind a mirror yourself. Or, you have some good tips in making a really useful accessory? This is the place to show what your hands can do...
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michael
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need help for lighter weight tube making(closed)

Post by michael »

hi,

Closed...
Last edited by michael on Wed Aug 08, 2007 3:30 pm, edited 1 time in total.
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kingkong
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Post by kingkong »

i always thought aluminium is the only viable choice for rigidity and light weight. are there others with superior characteristics?
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Meng Lee
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Post by Meng Lee »

If you have the captial, you can try carbon fibre.
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kingkong
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Post by kingkong »

won't carbon fibre flex?
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ariefm71
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Post by ariefm71 »

either aluminum or carbon fibre will flex. you need to have it rolled (for aluminum tube) or put custom-machined end rings to strengthen it. A 12" OD, 60"L CF will cost ard $1500.00 (not worth it unless you're making a premium scope).

See here for alternative: http://www.singastro.org/viewtopic.php?t=3352
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denebman
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Post by denebman »

I know a supplier in China who is making 290 mm id, 1.5 mm thickness and 1500 mm long carbon fibre tube for dobsonian telescope. Cost is roughly S$ 600~700. The correct way to make rigid CF tube is to multiple spiral bound it from a mold rather than roll and reinforce it. I am considering to make an 8 inch dobsonian using his 240 mm id CF tube in near future.

Sonoco Singapore Pte Ltd also makes kraft paper sonotubes up to 1000 mm ID however they require a minimum order of 50 meters.
http://www.astronomy.com.cn/bbs/attachm ... update=yes
Last edited by denebman on Thu Aug 02, 2007 4:24 pm, edited 1 time in total.
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denebman
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Post by denebman »

If you read Chinese, here is the link:
http://www.astronomy.com.cn/bbs/viewthr ... 3%E5%BE%84
10" Telekit with Zambuto optics~TMB 152/1200 (construction)~Takashi Mewlon 210~TMB 80/600
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ariefm71
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Post by ariefm71 »

Slightly OT, will a 1.5m long tube fit the backseat of a cab?
michael
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Joined: Tue Aug 31, 2004 5:22 pm
Location: singapore

tube

Post by michael »

hi

thanks for vluble dscn....i am not going fo crbn fiber. i just want to make with alluminium...i think i can get it more easily and cheaper way right?...also not so heavy weight.

Now i need to know which thickness of the wall should be btr for this kind of tube? 1mm,1.5mm or more..?

thank you...
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