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View Full Version here: : The 'Kunama Pier' V1, V2 and V2.1


Kunama
26-09-2012, 02:45 PM
Having got this pier recently (as part of a package with my Vixen scope) I thought it could do with some restoration, being corroded and a bit worse for wear. I did take a pic before but for some reason deleted it so you just get to see the finished product:

A 123cm high steel tube 112mm diameter with top plate adapter modified for EQ6 type mounts. Instead of the original loose bolts I have modified it and the adapter plate is now affixed using 3 inverted dynabolts with double nuts to lock it into level. The Dynabolts are drilled through the plate and welded above and below.
The base plate is a cast iron fitting threaded onto the pole and locked in place with 4 ss allen bolts and some iron oxide (rust).

This got me thinking about piers in general and the shiny one is going to be sold and replaced with Kunama Pier V.2.1 which is a 230mm diameter 140cm high steel discarded CO2 weighing in at a healthy 50Kgs empty.

I will be fabricating a 16mm thick steel base plate for it as well as a top plate to take my mount (when I eventually choose one !!!).

The plan is to place the mount into my future observatory and then fill the bottle with used engine oil to absorb all the ringing/vibrating etc. These bottles came from the local Rubbish Tip for $ 0.00 :):)

I also won a steel bollard on ebay yesterday (920H x 140Dia with base plate) for $25. That is in Sydney and I probably will not need it so if anyone in Sydney wants it for the said $25 get in touch with me quickly.

Here are the candidates for my Pier:
The tall one for the observatory (2014 build date?)
The black one for the back yard for northern horizon use

Kunama
26-09-2012, 02:51 PM
Just a Warning for anyone intending to follow suit:

Gas cylinders such as these may contain harmful, explosive or flammable nasties inside, if you are unsure of what it contained, make sure you find out before attempting any cutting welding etc.......

They should be inverted for gases heavier than air, righted for the lighter ones and watch out for the redback spiders when you flush them out !!!

EDIT: As noted below, some cylinders were made with an asbestos filler, in particular acetylene cylinders which are usually coloured maroon/brown stay away from those.

rally
26-09-2012, 10:31 PM
Matt,

Depending on the cylinder it may also have an asbestos filler inside it.
That is possibly why you got it for free.

So you may want to consider how you deal with this stuff before you liberate it and turn into breathable dust !

Rally

Kunama
27-09-2012, 06:35 AM
Thanks for the reminder Rally, I have edited the previous post re acetylene cylinders.

ZeroID
27-09-2012, 09:15 AM
Correct me if I am wrong but due to Acetylenes propensity to explode when pressurised it used to be dissolved in liquid Acetone in the cylinder. Hence acetylene cylinders should always be used standing up otherwise you get a nasty flamethrower as Acetone has very low vapour point. Definitely stay away from Acetylene cylinders for this purpose. I have seen the results of Acetylene cylinder explosions years ago and it ain't pretty.
Wasn't aware they had asbestos ( as well ? )

But those cylinders would make dang good piers though, hefty steel walls for sure.

Kunama
27-09-2012, 10:15 AM
That is correct, the acetylene cylinders have an inert packing material (used to be asbestos, as well as acetone which is dissolved when acetylene is introduced under pressure, when the pressure is released during usage the acetylene comes out of solution much like the CO2 fizz in soft drink bottles.

The safest cylinder to use is discharged a CO2 one that has had the valve removed then you know it is safe. Those have a grey/green coloured top.

Nico13
27-09-2012, 10:34 AM
The blueish coloured one was most likely an Argon bottle used for mig welders as a shield gas, (non flamible) and the Black one was Air or could have been high purity Oxygen.

So the Blue one should be pretty safe and make sure the black one is well vented.
Looks like the neck valves have been removed and sitting for some time anyway so you should be pretty right.

Just be careful with them.

Cheers

koputai
27-09-2012, 10:20 PM
Ah, everything old is new again!

http://www.iceinspace.com.au/forum/showthread.php?t=79998&highlight=pier

Cheers,
Jason.

ZeroID
28-09-2012, 11:22 AM
Necessity is the mother of invention ... :thumbsup:

Kunama
28-09-2012, 12:36 PM
Nice write-up on your pier Jason, pretty much what I am planning to do as well.
Thanks for the linky.

koputai
28-09-2012, 05:57 PM
Thanks Matt, good luck with the build. Lucky bugger, you'll have much better skies down there!

Cheers,
Jason.

5ash
13-10-2012, 11:01 PM
Jason ,
that last picture of your pier show's a top plate with what looks like an adapter for an eq mount? Is that correct?
Philip

koputai
14-10-2012, 02:14 PM
Hi Philip,

Yes, for an EQ6Pro, have a look at the pictures a bit further down that same page.

Cheers,
Jason.