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mental4astro
22-07-2013, 01:40 AM
Hi all,

Just wondering if anyone has waxed their steel OTA tube? A mate's tube has developed rust spots on it due to dew. I'm thinking it might be a good idea for two reasons: protects the steel some more, & the dew doesn't pool as much before running off but beads & runs.

Has anyone done this to their's? Is my thinking incorrect?

The mount would need to be particularly water resistant I would imagine. It could be subjected to more water. I dunno.

Ta,

Mental.

Wavytone
22-07-2013, 06:01 AM
Hi Alex,

Once rust starts it never stops - best to cut the area out and apply a paint system that provide electrolytic (cathodic) protection. Wax or fish oil (sometimes applied on cars) won't stop it and it will look pretty daggy after a while as it will collect dust and dirt, which trap more moisture and ultimately it will probably corrode even faster.

The common one is "Galmet" used for "cold galvanising", looks like silver paint. There is another though, used for steel structures for roads - a dark grey, dull micaceous paint used on stuff beside roads. I've used this before and it worked well. Both won't look good on a scope, though.

Kunama
22-07-2013, 07:31 AM
"Fertan" Rust Converter is your answer Alex, it converts iron oxide (rust) to ferric tannate which can then be painted without any more ongoing corrosion.

As Wavy mentioned, Galmet is good to paint over the repair.

torana68
22-07-2013, 09:06 AM
To stop rust forming use a car polish on the paint. If rust has stared repaint may be best, but a good polish may stop it getting worse.
Roger

astro_nutt
22-07-2013, 10:08 AM
Most OTA's have lots of holes in them to hold mirror's, focusers, etc. When you unscrew somethig you can remove the paint from the hole in which rust can form. It pays to check the holes to see if the paint has been damaged. If so, clean it with a bit of metho then paint it with some clear nail plolish. Soften some candle wax and coat the screws threads before using them. Every bit helps.
Cheers!

TrevorW
22-07-2013, 10:43 AM
Buy carbon fiber it doesn't rust ;)

mental4astro
22-07-2013, 11:07 AM
Thanks for the replies, lads.

Yeah, I'm aware of rust cancer. I'm not looking to stop it - the wax ain't gonna do that. Even if the tube were pristine, anything to be gained by waxing it? More of a way of dealing with the dew forming on the tube.

Astro_nutt, thanks for the suggestion of checking and dealing with the existing holes in an OTA. Capillary action under washers and nuts would make these areas a magnet for water to get sucked into and cause damage.

If only I could afford a CF scope... :lol:

Kunama
22-07-2013, 08:02 PM
Alex if your scope is not rust affected you can wipe it over with RainX Protectant, then any moisture will just run off like mercury.

LewisM
22-07-2013, 09:52 PM
Wax on, wax off...

I just always make sure I wipe down my equipment with a towel every time, and I do use Ballistol on any rustable metals every couple of months (which is actually not a lot on a Vixen :) Nearly ALL aluminium or VERY well painted)

Had a small reflector that had a rusty tube. Cleaned it up with a wire wheel and repainted it with hammertone as an undercoat before the colour coat. Hides a LOT of boo-boos :)