Mirror refurbishing NZ?

[Finite]

Hi folks, I have bought a big old 23" dob I wish to refurbish. First-up I'd like to get the mirrors both re-coated, - I am in NZ though! Can anyone point me in the direction of someone who can aluminize here?

Also any advice on removing the remains of the existing coating would be gratefully received. I don't know whether these are silvered or aluminised.

About thirty years ago I cleaned up a 6" and a 8" mirror then had them recoated by a company which did vacuum deposition in Auckland, but they are long gone. I have tried Kiwistar Optics some weeks ago but got no response to my email.

Any suggestions?

regards, John

[pixelsaurus]

For that size, I believe Kiwistar may be your only option, and it won't be cheap. From memory it used to be $700 odd setup charge and aluminizing on top. Another option may be to silver the mirror. I believe there are kits available online.
A member of this forum maybe able to point you in the right direction
http://www.iceinspace.com.au/forum/member.php?u=9065

[Finite]

Thanks Mike, I'll pm him and see if he is willing to silver the monster for me.

I do remember the last mirror I had done was at someones home in Te Atatu South, Auckland, but that was 30+ years ago so I've lost his details..!

[pixelsaurus]

Peter Wilde in Palmy used to do mirrors up to 14". I heard he had some leaks in his plant and was out of commission. I don't know if the issue has been resolved. Clive Rowe down south "inherited" all the old Mt John gear but I have heard it leaked and was not worth the repair. It seems our options are limited these days.

Peter Brock lives up your way. I think he makes large mirrors so he might be worth a try. He has to get them coated somewhere. No details for him I'm sorry though he does frequent other forums.

[dave brock]

Hmm.
Dave Brock here (Hamilton).
When I had my 20" recoated in Nov. 2014 Kiwi Star charged $20 per inch/dia. + gst. There has never to my knowledge been a setup fee on top.
Do you know how good the figure is on the mirror? Is it the one Chris O'Conner was selling a little while back?

Dave

[N1]

Went to KiwiStar after doing some research.
It's under the umbrella of Callaghan Innovation.
Had an 18" recoated there 3 months ago. Total cost was $400 incl. GST.
Graeme is great to work with.

John, see PM

[Finite]

Hi Dave, yes that's the one. Chris was of the impression the mirror was figured by Graham Loftus, whom I understand used to produce some large mirrors in short time, and I have to confess I wouldn't know how to tell good it is even if the mirror had an excellent coating (it doesn't, it is deteriorating). Have you seen the mirror? At only $340 I couldn't resist picking up the telescope to have a play with.

[Finite]

Thanks Mirko, I have seen and replied. Cheers!

[Finite]

Hi Mike, I see Dave Brock has responded to this forum thread. Thanks for the headsup - it's exactly the sort of info I need as I really don't know where to start. There could be someone local(ish), and if so I'm sure someone of Iceinspace will know! Several months ago I trawled through the forum looking for details, took me so long I thought then I'd ask for help straight up this time. I do seem to recall from that first hunt that Clive Rowe was non-operative now. I may be wrong. I am likely driving to Queenstown at the end of this week, so a visit to Kiwi Star might be on the cards.

[pixelsaurus]

Cheers. Sorry I got Dave Brock's name wrong. I was just going to post a correction but I see he has beaten me to it. Sorry Dave.

[dave brock]

No problem Mike.
I once lied on national television (It's in the bag) by saying Peter Brock was my Uncle :whistle:

Dave

[Finite]

I think it would be quite frightening to get a message from Peter Brock

[Finite]

Ha! You might even get a message from Selwyn Toogood, after that confession...or was it the newer show?

[dave brock]

The newer show. About 25 years ago. Tinsley I think.
Went something like...
Next up David Brock, any relation to Peter Brock?
Yeah he's my Uncle.
Really?
No
(Lots of laughter from the audience).

I ended up turning down $500 and won a road map.
I guess he got the last laugh.

Dave

[Finite]

I got side-tracked whilst travelling the Sth Island, and have ended up buying a 20" dob...now all I have to do is fit it in with my luggage 😕

[Finite]

But I don't have to recoat this scopes mirror or rebuild it...!

[dave brock]

I saw on TradeMe that you bought the 20".
I'm sure it'll end up being a lot better than the 23".
Well done.

Dave

[Finite]

Thanks Dave, am looking forward to it. I wonder which suitcases I'll have to bin to fit the scope in the car. I'm meeting up with the seller tomorrow evening or Friday morning. I would still be keen to meet up with you to have a look at your scope and get some pointers on how to analyze the quality of the 23".

[pixelsaurus]

Why do you need a suitcase? Most people just fill them with rubbish they never use.;)

[Finite]

You're right! My wifes suitcase it is then.

[dave brock]

If she sees that comment you might have room in the front passenger seat.

Dave

[Finite]

Funnily enough that's exactly where I had the primary mirror sitting 20 min ago. So you may be right.

[Finite]

Well that was cool. The scope broke down into components easily enough, and went into the suv ok with the back seat folded down. I think in the morning I shall have little trouble putting the luggage in there with it. We'll see. Just as well I didn't come to the South Island in my old Audi ur-quattro, which I had considered doing for the fun of the drive.

And good news, the mirror isn't kicking my very good wife out of her front seat position. It just sat there while I jigaw-puzzled the big bits into place in the back.

Arthurs Pass is a very small locality tucked away in the Southern Alps, and the overnight accomodation I booked here turned out to be directly across the road from the seller. So easy!

And for some extra dollars I came away with a Tele Vue Paracorr, a Tele Vue 27mm Panoptic, a Tele Vue 9mm Nagler, and a GSO Barlow, all in 2". Am very well pleased (thank you my very understanding wife).

[pixelsaurus]

Happy you survived Arthurs Pass. I assume the keas left you alone. Enjoy the dob.

[Finite]

Hey Mike, yes and what a treat of a spot Arthurs Pass is. No Kea sightings, no bitten-off tyre-valves and no windscreen wiper rubbers pulled to bits. Did hear the Keas this morning though, somewhere up in the beech.

Now I'll have to figure out whether to pursue re-commissioning the 23" dob, once I've reassembled and used this 20" (damn, wish it was back together now, - the skies look good over Blenheim tonight). The 23" is F5.25 yet is still a sizeable ladder job to get to the eyepiece.

[pixelsaurus]

Years ago, the locals noticed that the keas didn't like the Warden of the Youth Hostel. When he was away for the day (presumably in Chch), the keas would disappear. When he was at home during the day, those sods would roll rocks down the YH roof all day. :lol:

[Finite]

Well home again. Now to reassemble this toy. Off the Interislander ferry, which was late arriving so also late leaving, then drove to Napier, arriving going on dark but no accomodation anywhere as filled to brim with horsey people there for a five day event! Taupo then, - no accomodation there anywhere as was filled to the brim with Marathon people! So on north to home. What a day.

Mike, what a cool story about the Arthurs Pass Keas lol. I hope they left the rocks alone at night, but I bet they are up early so perhaps no sleep-ins for the poor man running the hostel. What do you do to engender the wrath of such creatures I wonder?

We stayed at that Hostel the other night, the Keas were in the trees above it. But we had a chalet across the road from the main complex, - thankfully, by the sound of it.

[Finite]

Wasn't much room in the car.

[pixelsaurus]

Maybe when they rolled the rocks, they got a reaction. I guess even keas are allowed to have fun.

One of them did steal my sisters cheese and onion sarnie. It was in one of those triangular packs. When my sister sat down at the table, she was being scrutenised. As soon as she let her guard down, vroom. It sat on a shed across from the cafe and demolished the pack and the sarnie. If you are not fast, you're last.

Good skills getting the beast home. Next time, drop me a PM. I may have a spare bed.

[Finite]

Wow what a kind offer Mike,- thank you. We certainly were stuck. It was a 50/50 which way we came back up the island, but the two major places we were considering staying were stacked, - we would've known had we done the sensible thing and checked for accomodation the day before. That's what being spontaneous does to one I suppose! At least it was a good solid run through. But I felt every jar in the road, and every knock, creak, and rattle from the telescope, wondering how easy it's going to be to collimate later...I haven't studied its provisions for that. The secondary's under wraps and the mirror box is locked (I have to cut its padlock off).

This scope came from Foxton way, so not that far from you. The guy I bought it from took it to Arthurs Pass with him when he went.

[dave brock]

The fact the primary is overcoated means it was made overseas or did the owner send it to Aussie to be coated?

Also, time to update your signature?

Dave

[Finite]

Of course! Hadn't even thought about my sig.

Been busy as today, unpacked etc including put telescope components in the hallway - there just isn't room in the garage, - took primary out of its transport case and inspected: needs cleaning, cleaned up contacts in telrad got it going, (it wasn't at first), run water to a trough to refill it, tracked down a leak in its pipe in the paddock, shaved three dogs, took my parents to see their house under construction and photographed it, did supermarket run, picked some figs, sorted goats, chlorinated the pool, checked over some drone footage from Kaikoura Coast. Whew, I want to go back on holiday! Only it wasn't actually all holiday, I had some work too.

Re the mirror, I've got to correspond with the owner. He did mention that he had the mirror reshaped or similar,- mentioned whilst we were disassembling it and I were half-listening - I'm a dunce, got pretty sidetracked with negotiating for his eyepieces and paracorr. I definitely want to find some more about the scope though: who made it and where, etc.

[dave brock]

So, have you had a chance to try the 20" yet. How's it looking?

Dave

[Finite]

Hi Dave, sorry for the late reply, I've only just come back to this thread today.

But yes I have...one night only a couple of weeks ago, when the sky looked spot on as evening fell. My scope was occupying the hallway UNASSEMBLED(!!) and I had to put it together, - fast. Thankfully at the time of disassembly I had placed stick-on numbers on struts to show which part married up to where. I had bought the stickers at a stationers along the way and the sticker sheets had several sheets of letters so I had three A's, three B's etc. Even so, before I got some on the previous owner had taken some struts off. So I didn't know which frame went which side...took me a while longer to get it done than I expected.

Anyway, uncollimated and still with dust and some dried dirt smeared on both primary and secondary, I got to look at M42 just before it sunk into the treetops. It looked pretty good I thought. Also jewel box cluster (what a novice I am eh?!) I didn't use the Paracorr coma corrector and on star fields the image was quite blurry from about halfway out to the edge, something which I didn't see so much with the nebula. I am interested to see how the corrector helps.

Then Jupiter. For the first time in my life I saw more than two bands, - 3 for once!

I have bought a collimator and found it was fairly well-out, which I corrected with the secondarys' knobs. I have yet to clean the optics and collimate properly and am looking forward to it, but man I am such a novice really. I see from online that distilled water is the go for rinsing off the mirrors after cleaning.

Still thinking about a 14" SCT though (there's one for sale in Aus at the moment and I have been given the tentative authority to buy so sent an enquiry today), for the goto and tracking which is something I have never really had. I once owned the 10" LX50 which is on Trademe at present, and for which I built a trolley and then sold it as I wanted a LX200 SCT for the goto and better tracking. AP is a casual interest but sadly these fork mount SCTs are not so good for that I understand, even if on a good wedge, but still the pull for the 14" SCT is strong...

Anyway, I am pleased with the 20" dob so far, have yet to clean it up and collimate then drag it outside again for Round 2. The stiction and movement was better than I expected it to be, and it didn't jiggle all around either after moving onto an object, it settled down really quickly. I am happy, and can think about selling the 23".