Ally Tube

[Frank the Troll]

Can't seem to find any ally tube sources for a 10" mirror

Need an ID of 10.5 or 11"

Have tried a couple, but seems they cant be bothered to respond

Any ideas needed?

Cheers

[fwm891]

Frank - only place I can find is: http://hastingsirrigation.com/node/13

The may have an off-cut from a damaged length or similar

[Moonshane]

have you considered a truss based dob?

or perhaps you could try an octagonal home made wooden one

[Islander]

Mine's a square wooden one - easy to construct and works perfectly well

[steelfixer]

Hi Frank.

How much tube do you need ?

What wall thickness ?

[Frank the Troll]

Hi Frank.

How much tube do you need ?

What wall thickness ?

Hi Steelfixer

Wall thickness, as thin as poss, reckon 2mm should be strong enough

Would that be ok?

Lenght approx 1700 to allow for any errors

Its for a 10" mirror, focal length approx 1100

[JamesF]

2mm strikes me as being very thick.

James

[Frank the Troll]

2mm strikes me as being very thick.

James

I did say as thin as poss, no idea, as not worked with ally before.

I hate metric!

1/16th inch

have you considered a truss based dob?

or perhaps you could try an octagonal home made wooden one

Yes, it will be a dob, but will also be used on a SkyTee-2 mount, so wood be too heavy, and truss not pracital on a mount

[steelfixer]

Hi Frank.

If you want it that thin why not get a piece of sheet and roll it up?

I do see you running into problems though if you are going to put it on a mount.

How are you thinking of attaching it ?

Graham

[Moonshane]

Orion Optics would probably sell you a tube. I bet if you wanted one unfinished and without any holes drilled it would not be that expensive?

[steelfixer]

Orion Optics would probably sell you a tube. I bet if you wanted one unfinished and without any holes drilled it would not be that expensive?

Now that is the best idea I've seen yet.

Nice one 'Moonshane'

[libraryman]

OO roll their own tubes i belive, i was quoted £90:00 to have a tube rolled with a folded seam by a local metal shop, i did not take the option at that time but restored my own, powder coating was a tenner by the same people who do OO's

Ray

[Peter Drew]

OO have rolled tubes for me in the past, thin aluminium sheet is not cheap these days, I purchased a 6X3 ft X 1.25mm for £96 a couple of weeks ago.

[Frank the Troll]

Orion Optics would probably sell you a ,tube. I bet if you wanted one unfinished and without any holes drilled it would not be that expensive?

Ok, all sorted, fired off an email, John was very helpfull, had 1 of 2 left in stock from their move, and just the right size (black glass tube £90)

Cheers Moonshane

[Auntystatic]

Now that's what I call a result.

[Moonshane]

great stuff Frank - glad you got one. very light too!

[Frank the Troll]

great stuff Frank - glad you got one. very light too!

Yes very light, easily balanced on the palm of my hand, very surprised

11" dia 62" lenght - mat black inside, glass black powdered coated

[Moonshane]

Nice!

[Frank the Troll]

I'm tempted to fibre-coat it, and not your usual black, but a very very dark purple!

And then design a label calling it:

The Dobs Trollocks Mark 1