Carbon Fibre Telescope Tubes.

[Tandum (Robin)]

Does anyone know of someone on Oz who can supply one of these tubes. I'm looking at swapping out the 10" Newt Tube for fibre. I've found this mob in china and have sent them a query, but can I get one in Oz?

[gbeal]

Hi Robin,
I built one a few years ago, and it got coerced across the ditch by a Dunkeld guy. I am onto another one, coincidentally for my 10" f5 newt, so let me get this from the guy doing it and see what it is like before I rave on about it.
Shipping will be a killer though, 300mm round, and 1250 or so long, weighing about 2 kilos,
Gary

[Tandum (Robin)]

Gary, I heard back from china already. They said they'd quote for the tube and shipping on Monday

[AlexN]

You could try Public Missiles in the USA.. They do CF tubes for a lot of SCT's I'm sure if you contacted them and said you wanted one for a newt that they would do it. Shipping would be a killer though.. NZ might be a better option.

[gbeal]

Robin.
It will be interesting to see what the cost is from your enquiry. I made an enquiry there many months ago and it was quite expensive. Nice work, but expensive.
Public Missiles were the same, stunning tubes, but prohibitively priced, plus the shipping angle took it's toll and I went DIY.
Gary

[Tandum (Robin)]

I can't find anyone in Oz that makes them, all I can find are resellers and calculating an upsize from the prices they have listed on line puts it up around $800 for the tube alone. DIY is out for me, don't have the know how. I've just had a payment request for something else I've ordered so there's not a lot of funds left to squander either

[Waxing_Gibbous (Peter)]

Robin,
There's an Australian mob that make super-high quality CF tubes for the Oil & Gas industry. Before anyone starts groaning , they are MUCH better by any measure, than anything commercially available for telescopes. I doubt they would be particularly cheap, but they produce tubes in standard sizes that should be adaptable to your purposes.
I SHOULD have their name directly to hand, but its lost in my other PC somewhere.
Will PM you their details if interested.

[Tandum (Robin)]

Sure Pete, why not. The savings in post might outweigh the extra cost.
It's good to know someone has the tools to make them here rather than just import from china and resell.
I believe real ones need to go into an autoclave to presure cure the resin.

[Wavytone]

Peter, if you find it I'd suggest adding it to the sticky Astonomical equipment manufacturers list, I'm sure others might find it useful.

[Tandum (Robin)]

China came back with US$428 for the tube, US$440 for the mould + shipping

I've asked if they have a standard size that don't need a mould. She told me yesterday they sell these things to the US so maybe they have a mould that's close enough

[AlexN]

Sounds about right Robin.. CF tube itself isnt horribly expensive, but try to ship it somewhere (despite its low weight) the shipping cost gets calculated by the items cubed dead weight rather than actual weight, and before you know it, a $550 CF tube becomes a $1150 Golden monument.

[Tandum (Robin)]

She's talking US$200 shipping via fedex but there is an air option to the airport only yet to be priced.

[gbeal]

If you c an do a tube that works for US$428 plus shipping I reckon you are onto it. The mold is the killer. I don't think shipping will be THAT much, but as Alex says, it determined by "Dim Weight" that is size, not weight.
Gary

[AlexN]

Agreed - if its going to work, and is $428 USD. go for it...

I just rechecked the PublicMissiles adds on Astromart before, they have dropped considerably in price since I had my C11.. Down to 285 for a C11 tube.. They do say they do custom sized tubes on request.. It might be worth asking them how much for your tube..

[Tandum (Robin)]

One of these would be about US$350 shipped and pre flocked, so there's the competition.

She has a mould near 300 ID, it's 298.xx mm

[M_Lewis (Mark)]

Making a CF tube isnt hard at all. Just get some CF matting, epoxy, a C&C foam cutting machine to do the exact size you want for the tube, and a vac machine, with the appropriate release agents to get the silky smooth glossy finish when you vac set it.

I've made many RC-glider wings over the years out of CF, kevlar and fibreglass this way and it's unfortunately time consuming. At those prices you got above, it's really a bargain, as the CF matt is not cheap, and the time involved setting up and laying up all the glass, I fail to see where they are making any profit.

[gbeal]

And that is the sort of approach I have taken.
I have stripped the outer layers from an old sonotube, and have a layer of C/F on the outside. Each layer of C/F (dry) will end up being "about" 1.2 kilos, so it is still way lighter than the Protostar version, but it is an excellent option as the C/F on the exterior of the tube will add to the stiffness, and resilience.
Gary

[Tandum (Robin)]

Thanks for the input guys but I don't have the space nor facilities to make such a large tube here. Hell, I have trouble finding somewhere to put this one. I've asked her to quote on a tube using the mould she has (298.xx mm ID), using 6k 2x2 twill weave 30% resin, 2mm thick and the cheapest shipping She quoted weight at 3.78Kg earlier.

I think the mould fee was just going to be a xmas bonus for them

[Tandum (Robin)]

Final word on this if you where reading.
China was too expensive, the 298mm mould they had was only 1050 long so the final price from them came in at :
Tube: USD428.05/pcs
Mould fee:USD440.52
Shipping:USD205.58
Amount:USD1074.15

I also contacted protostar and was told they do not ship lengths over 36" off shore anymore

[koputai (Jason)]

Grumble mutter bloody carbon fibre mumble grumble......
I busted a 2ft x 2in x 1/2in carbon spreader on the boat the other day, luckily there was a spare in the country. 800 bucks later....grumble carbon fibre mutter grumble.......

Sure it's pretty stuff, but surely there are better/more economical materials to make scope tubes from?

Cheers,
Jason.