Plywood Refractor 5" f12

[anj026]

Hi fellow telescope nuts,

Over the last few weeks I have been making another refractor. I purchased the lens from Istar, it is a 5 inch f12 R30 doublet achromat lens in cell. http://www.istar-optical.com/istar_019.htm

The tube is built up in the same way as my 6 inch f15.
http://www.iceinspace.com.au/41-340-0-0-1-0.html

There is a thread on Cloudy Nights ATM forum detailing the whole build with lots of photos.
http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Board/atm/Number/4572197/page/0/view/collapsed/sb/5/o/all/fpart/1

If anyone is interested in building a scope like this with thin ply then I encourage you to go ahead and give it a try. It is a step by step methodical process and lot's of fun. Please ask questions and I will do my best to help.

I haven't completed the mount yet but have cobbled together a means of using the scope. I only managed a brief first light last night and will follow up with more as I get to use it more. I am happy with the lens for now.

Andy Jackson
Perth WA

[dannat]

Terrific work andy:hi:

[mswhin63]

Beautifully crafted piece of gear. It looks so easy. Definitely want to have a go myself (When I get time) :)

[casstony]

The glossy paint gives it a professional looking finish - I like the tripod too.

Clever way of getting the bevel in that CN link.

[FlashDrive]

That's very nice Andy .... great job :thumbsup:

[anj026]

Thanks everyone for the comments.

Malcolm I will try and bring the scope out to Jarrahdale some time in the next couple of months, maybe July or August DSO night. You can check it out yourself. I would like to hear your thoughts.

Andy :)

[mswhin63]

No problems looking forward to it. :thumbsup:

[scopemankit]

That's a beaut of a refractor!

[lacad01]

Beautiful piece of craftsmanship Andy, looks great. Look forward to hear how it performs :thumbsup:

[stringscope]

Hi Andy,

Fantastic workmanship and an inspiration :thumbsup:

Cheers,

[M54]

Hi Andy,

That's a fantastic job, and I love seeing neat tricks like you used for the bevels.

Can you tell me what the cost involved in building this is?

Thankyou for a great thread...

Molly.

[solissydney]

A couple of years ago I built an 12 inch F/5 plywood tube using two sheets of ply.
It saved me 5 kg in weight over the steel tube. Would do that again if needed
Ken

[anj026]

Thanks everyone for comments.

Molly, the cost is aout $550 AUD for the lens including postage, the GSO focuser is about $150, the finderscope and diagonal (GSO) about another $150, a sheet of top quality 4mm marine ply is around $120, various bits like screw, glue and paint maybe another $50-60.

You can make it cheaper but when you are investing a lot of time into a project like this it will be more satisfying in the end if you use quality materials.

Regards
Andy

[renormalised]

Beautiful piece of craftsmanship:):)

How's it perform??

[anj026]

Performance is very good. High contrast sharp images with very low amounts of false colour. The above link to the Cloudy Nights build thread has an observing report at the end that describes a comparison with a 6" f15 achromat stopped down to 5" f18.3. The observing conditions at the time were not ideal. I am away from home now for a few weeks but will try more observing tests and comparisons when time permits.

Andy

[allan gould]

Well done Andy - inspirational.

[stringscope]

Hi Andy,

A beautiful telescope. Congratulations :thumbsup: I would love to look through you refractors one day when I am in Perth.

Cheers,

[SkyViking]

That's a beautiful piece of work. I guess there are not that many home built refractors around. Very interesting, thanks for sharing this.

[mswhin63]

Shame about the weather here in Perth, wouldn't have given a lot of opportunity for testing.

[anj026]

I have been away from home (and my scopes) anyway Malcolm, but will be back again next week. Looking forward to finishing off the mounting and doing some more observing, weather permitting.

Andy

[David Fitz-Henr]

That's a nice looking scope Andy :thumbsup: Nice to see a long focus achromat for a change.