How stupid!

[Stardaze]

11 hours ago, johninderby said:

You may have a future in helping plan the HS2 project then. 😁

I didn’t measure the centre bolt but must be 50mm. The central spider piece is 20mm and I’m 7-8mm at the moment. There’s a couple a mm there still which I think is needed. 
 

Still... I won’t be doing it today 😄

Edited May 31, 2020 by Stardaze

[Stardaze]

I’ve had enough, it’s beaten me! Where’s local to Redditch that I can have the mirrors collimated properly? 
 

I can see it’s twisted but it isn’t if I look at it down the tube. The first part of getting the holder concentric is simple enough but it tilts the central donut? I’ve twisted it in various angles and it won’t square it. There’s something not right here, maybe it’s me but I’m at that point where I’ve spent hours and I need to watch someone who knows what they’re doing. I’ll drive to within 100 miles of Redditch to get this sorted, any recommendations?

[johninderby]

Looks like you have the secondary spot on and can move onto adjusting the primary mirror.

Woild suggest after slackening off the primary locking screws get a small steel rule and adjust the clearance betwen the mirror and cell to be the same at each collimating screw. Then you shouldn’t be too far from being collimated and can start adjusting the mirror.

[Stardaze]

36 minutes ago, johninderby said:

Looks like you have the secondary spot on and can move onto adjusting the primary mirror.

Woild suggest after slackening off the primary locking screws get a small steel rule and adjust the clearance betwen the mirror and cell to be the same at each collimating screw. Then you shouldn’t be too far from being collimated and can start adjusting the mirror.

John, you’re a genius! Thank you, that’s all it was. Sorted and very happy with it. Easy when you know how!

[johninderby]

Glad you have it sorted. 👍🏻👍🏻👍🏻

The primary mirror can get so far out of adjutment that you get lost trying to get it right. Setting the primary level will let you find your way back and then it should only need tweekinng to get it spot on.

Edited June 6, 2020 by johninderby

[Stardaze]

16 minutes ago, johninderby said:

Glad you have it sorted. 👍🏻👍🏻👍🏻

The primary mirror can get so far out of adjutment that you get lost trying to get it right. Setting the primary level will let you find your way back and then it should only need tweekinng to get it spot on.

I couldn’t see the wood for the trees there, when all along it was that that needed to be levelled. I absolutely know how it all works now I guess, so confident I have earned my collimation badge. 
One of the primary knobs came off when I was levelling, my heart sank. Thankfully it’s not difficult to pull back on the cell to screw it on. Another of life’s lessons. Scope and myself now not rendered totally useless 😆

[Ricochet]

The primary collimation knobs will pass through springs. Make sure that the screw that came out still has its spring, because if it falls out at some point in the future, you'll have a hard time finding it again.

[Stardaze]

35 minutes ago, Ricochet said:

The primary collimation knobs will pass through springs. Make sure that the screw that came out still has its spring, because if it falls out at some point in the future, you'll have a hard time finding it again.

It does. It didn’t come off but clearly two of the screws aren’t screwed in much really which makes me wonder whether half a turn to all, will help keep the collimation from drifting. I’ll see how I get on, just need some clear nights now.

[Ricochet]

1 hour ago, Stardaze said:

It does. It didn’t come off but clearly two of the screws aren’t screwed in much really which makes me wonder whether half a turn to all, will help keep the collimation from drifting. I’ll see how I get on, just need some clear nights now.

I think a few turns on all of them would be a good idea. In my mind at least, compressing the spring should make not harder for the bolt to turn. Also, if they are screwed in further, there is less chance of one coming out again when you collimate in future. 

[Davey-T]

On 30/05/2020 at 09:40, johninderby said:

Baader gives instructions for cleaning newt mirrors with the fluid. 

Hi John, can you point me to the Baader instructions, been searching round their site with no luck, they say "see separate instructions for mirrors" so why don't the silly boys make that a hyperlink ?

Had the Sharpstar 150HNT to bits and manged to stick my fingers on the mirror but it's pretty filthy anyway considering it's supposed to be new so might as well give it a clean now.

Dave

[johninderby]

It’s on page two of this pdf.

Newtonian Mirror-Telescopes

https://www.baader-planetarium.com/en/downloads/dl/file/id/110/product/1661/cleaning_and_maintenance_of_optics_a_short_instruction_guide.pdf

Edited June 25, 2020 by johninderby

[Davey-T]

5 minutes ago, johninderby said:

t’s on page two of this pdf.

Thanks John 

Dave