Revamp of club 12" Dob scope commences.

Frank Ryan · Post by **Frank Ryan** » Sat Oct 04, 2008 8:09 pm

Dave Lillis wrote:Frank,
The standard coating from orion is 111.23 pounds sterling
and the hilux coating is 173.60 sterling
so suddenly this is looking pricey,

Ok yes it is.

Dave Lillis wrote:can you ask they guy you found what reflectivity % and durability are his coatings. Can you also ask the guy how many support points does the cell have and is it suspended on a sling, this is very important.

OK will do.

Dave Lillis wrote: The telrad can be a straight swap but we can leave the finder on the scope somewhere else since we have it anyway.

The secondary mirror glass might not need replacement but does need recoating. Can you measure the minor axis of the secondary so we can get a price on recoating it.

The spider and secondary collimation setup on that scope is atrocious and is difficult to setup. I can look at it again and see what we can do with it. If it was mine I'd dump it.

Ok lets think about the finder till later.
What exactly do you need me to measure?
No. Your opinion is good enough.
Lets look so at getting a new one.
I too found collimation of the secondary near impossible.
Can you suggest an alternative?

Dave Lillis · Post by **Dave Lillis** » Sat Oct 04, 2008 9:49 pm

Hey Don,
between yourself and Frank, sourcing the Formica sounds like its sorted.
btw, I seriously appreciate the offer for funds, the club is able to finance this so don't worry, we just want to be prudent about it, thats all.

Frank, the secondary mirror is basically an ellipse, one wide diameter and one narrow, can you measure the narrow one to the nearest millimeter.
In order to evaluate the secondary system, I need to have a good look at it, I'm going from memory of it going back over 12+ years which isn't great, are you around tomorrow to have a quick look at it.

Frank Ryan · Post by **Frank Ryan** » Sat Oct 04, 2008 11:08 pm

No.
Sunday is funday for me and my wife as its the only day off I have.
However, I will be off to the burren like a bat out of hell on Sunday night...
I'd really like to bring the dob along and see 'how bad is bad'
What do you think.

Don...
What we need basically is a bit of kitchen countertop
(glossy formaica finish - black if possible)
Not too thick - I can get you an exact size to the mm in the morning.
We then would have a good base to sit the dob onto.

If the weather is good tomorrow night you should come up to the site!
(but don't blame us if its cloudy!!!!!!)

Dave Lillis · Post by **Dave Lillis** » Sun Oct 05, 2008 12:09 am

no probs.
If we're going to go up to the Burren and be playing around with the 12", then we should go up there when its bright giving us a chance to see what we're doing. I'll talk to you about it tomorrow.
If we do decide to go, I'll send a club announcement over the text about it.

Don, if we go and you're able to come along, you wont regret it, its an amazing observing site, one of the best I've ever seen.

Frank Ryan · Post by **Frank Ryan** » Sun Oct 05, 2008 12:17 pm

Great.
I looks like it should stay clear for a time
(getting cloudy later in the night)

http://www.metoffice.gov.uk/satpics/latest_IR.html

The Jet stream is quiet also which is good news too.

http://www.metcheck.com/V40/UK/FREE/jetstream.asp

donkearns · Post by **donkearns** » Sat Oct 11, 2008 12:38 am

Frank Ryan wrote: Don...
What we need basically is a bit of kitchen countertop
(glossy formaica finish - black if possible)
Not too thick - I can get you an exact size to the mm in the morning.
We then would have a good base to sit the dob onto.

Frank, do you have those dimensions for me yet?
I will be talking to the guy on Saturday. (Later today!)

Cheers!

Don

Dave Lillis · Post by **Dave Lillis** » Mon Oct 20, 2008 11:32 am

Lads,
Just to let you know what I'm up to, I'm currently in the thrawls of getting a telrad on the web, I'm hoping to have one in the next month or so.

Frank, you mentioned that you wanted me to ring the guy regarding the mirror cell, can you send me his number if you still want me to do it.

Frank Ryan · Post by **Frank Ryan** » Mon Oct 20, 2008 1:16 pm

I've sent on his details Dave.
Don.
I'll measure it tonight.

Dave Lillis · Post by **Dave Lillis** » Wed Oct 22, 2008 11:30 am

I've found a telrad for 49$, it should be on the way soon.
Frank, I really need to see the secondary + holder before I talk to the mirror guy, maybe I can do this next week or something ?

Frank Ryan · Post by **Frank Ryan** » Wed Oct 22, 2008 11:41 pm

Grand. It'd have to be more twords the weekend though.

Dave Lillis · Post by **Dave Lillis** » Thu Oct 23, 2008 10:19 pm

Its a good thing the telrad is cheap, the dollar/euro rate is really going bad for us, anything expensive form the US is a whole lot dearer now!
I hope it'll be here in the next week or 2.

John O'Mahony · Post by **John O'Mahony** » Sat Oct 25, 2008 5:45 am

Just a silly thought. Would the cost of upgrading the club scope be close to say the cost of an 8-10" GSO dob? This is much easier to cart around and has little to no maintenance, good for sidewalk nights etc..

Dave Lillis · Post by **Dave Lillis** » Sat Oct 25, 2008 9:34 am

A fair point John, we're hoping to get the scope up and running for less then 300e, all going well, what the price of the GSO Dob ?

John O'Mahony · Post by **John O'Mahony** » Sat Oct 25, 2008 11:19 am

You would pick up an 8" for that. The main problem with the club scope it that it is so big and heavy it doesn't get any use by the general club members. It looks great on display but I wonder if we get real value out of it as a general purpose scope.
For 300 bucks it is worth repairing. If it was nearer €500 I would buy a new 10-12" which would be far easier to transport and set up and would get a lot more use. Just a thought.

Frank Ryan · Post by **Frank Ryan** » Sat Oct 25, 2008 3:39 pm

A very fair point and one worth discussing.
There is also the option maybe (just throwing it out there) of making it into a a truss scope?
http://members.cox.net/cdfellows/OTA_Finished.jpg