Paint job for dob

[haitch]

Hi,

I've been around the forums for a little while but I guess I've now become a DIY astronomer.

I'm in the process of doing up an old 14" Darkstar dob. I've started but I got a long list of things I want to do.

First thing I did was give the mirror a wash - it needs recoating but was also filthy and I wanted to check it would be worth it...I think it is. Just waiting for payday.

2nd I've changed the focuser from a 1.2" R&P to a 2" Crayford style

The dovetail shoe arrived this morning from FLO for my RDF so I can add that now as the butchered binocular finder is pretty carp. Already made a bracket for my laser pointer but discovered it doesn't like getting cold so not really up to the job. (Anyone know if that's due to the laser or the batteries?)

I want to flock it for when the mirror is recoated so will have to figure the best stuff for that.

Anyway to the point. The missus says it's big and ugly to which I pointed out it's for looking through not at and that she's lived with me for over 14 years so why start moaning about things being big and ugly now? Well it did get me thinking on giving it a paint job. I'd like to turn it a nice scientific white and I've ordered some of this

http://www.t-molding.com/store/product.php?productid=50&cat=3&page=1

to edge up the 3/4" plywood base (much cheaper from US even after postage) which I also want to sculpt into something less boxy and more shapely.

My dilemma at the moment is how to paint it and what to use.

I read the pimping my scope thread but wondered if car spray paint would be tough enough, for a heavy dob that gets shifted about a lot, without baking and also how it will take (the tube is plastic, similar to a drain pipe but 16" diameter). The current finish is a blue hammered effect which I will probably just lightly sand to give it a key. My other thought was just gloss white but I can see the runs in it before I start!

A professional paint job is out of the question due to cost.

Anyone got any experience?

Here it is at the moment

(click to enlarge)

[Ant]

I look forward to seeing this develop.

I would have said that car paint would be fine for the tube, but what about some sort of Yacht varnish for the wooden parts (remove back to bare wood, then varnish).

My dad uses quite a lot of Yacht varnish (not on telescopes admittedly) and it looks fantastic!

Ant

[Astro_Baby]

Car paint would work ok but test a small bit first. Cellulose paints will create bad reactions in some other paints especially enamels. One hit of car paint and an enamel paint will bubble underneath.

Cellulose can also be destructive to some plastics but if its done lightly, not too much at a time its normally ok. Cant say for duability and flexibility but it sticks to cars ok and they are out in all weathers.

[haitch]

I look forward to seeing this develop.

I would have said that car paint would be fine for the tube, but what about some sort of Yacht varnish for the wooden parts (remove back to bare wood, then varnish).

My dad uses quite a lot of Yacht varnish (not on telescopes admittedly) and it looks fantastic!

Ant

Thanks for that suggestion. My only concern is what sort of condition it is in underneath. It looks like there could be some filler in places. Might strip a patch back - nothing to lose if it's going to be painted anyhow.

The other alternative would be to laminate it with formica or similar but that would have to be scrounged as I understand new sheets can be pretty steep.

Or, I even thought about making an equatorial wedge. In which case I could completely redesign the mount whilst I'm at it.

I got this scope with the intention of it being a scope for life (to cure my aperture fever once and for all) and I want to make sure I get it right.

I'd also like to get rid of the boxy construction around the tube with the rings on that sit in the mount (new to Dobs so there's proabably a technical term I'm missing there) but haven't got a clue what could replace it that didn't look so chunky. I guess it would have to be metal and that would probably be costly.

Back to the mirror; does anyone know of anywhere for coating mirrors nearish to the Midlands other than Orion Optics in Crewe? I was pricing up and noticed it would costs twice as much at Orion Optics than at Galvoptics but the latter is obviously a trek and I don't fancy posting them. Is there a reason why Orion Optics are that much more other than the brand name?

Thanks everyone for the interest btw. I shall try and remember to keep a photographic record.

Here's one of the finder I just took off. I want a finder other than the RDF but this is useless so I shall manage with the RDF for now.

(click to enlarge)

Long, wobbly brackets and a tube (made from plumbing waste pipe) that restricts the aperture. I'd managed to give it a decent reticule (the old one was crumpled up fuse wire and blue tack) using heated and stretched fishing twine - that works well actually, with practice, if you just get it to melting point and pull it forms a really fine strand.

[russ]

so you are the chap who beat me to the Darkstar

It looks a great project and hopefully the end result will be well worth it. Checkout Beacon Hill Telescopes for re-coating, they seem very reasonably priced.

Good luck with it all

Russ

[haitch]

so you are the chap who beat me to the Darkstar

It looks a great project and hopefully the end result will be well worth it. Checkout Beacon Hill Telescopes for re-coating, they seem very reasonably priced.

Good luck with it all

Russ

Oops sorry!

I'd been scouring astrobuyandsell for the right scope at the right price so I guess I was lucky to go in just when it was posted!

Have you got any experience of Darkstar? I gather some have David Hinds mirrors but wouldn't know how to tell.

Thanks for the tip on Beacon Hill - they look priced between Galvoptics and Orion but that much nearer than Galvoptics. Looking round their site they seem very much geared up for the DIY astronomer - I can see I'm going to be spending a few £s with them!

[haitch]

Car paint would work ok but test a small bit first. Cellulose paints will create bad reactions in some other paints especially enamels. One hit of car paint and an enamel paint will bubble underneath.

Cellulose can also be destructive to some plastics but if its done lightly, not too much at a time its normally ok. Cant say for duability and flexibility but it sticks to cars ok and they are out in all weathers.

Inspiration...that's it - enamel paint like radiator enamel or appliance enamel. I'm sure they'd be ok on plastic.