Widening the aperture on a Pulsar Dome

[tomato]

This is maybe an off the wall question, but has anybody ever attempted this? Widening the shutter would be no problem but attempting to cut out the runners either side of the aperture and relocate would, I think, be fraught with difficulty as the geometry would change and it would be hard to fix them back parallel.

It’s just me trying to put more and larger scopes inside the dome than it was designed for.

[gorann]

Having only primitive DIY slide-off roof obsies where only the sky is the limit (or rather trees and obsy walls), I never had such luxury issues, but the very best of luck Steve😁

[tomato]

Thanks, although I appreciate the unrestricted sky  access a ROR allows I do value the shelter from dew and the wind that my dome provides. 
I can’t see me taking a jigsaw to the dome somehow, but I am curious about      knowing if anybody has tried this.

[gorann]

It strikes me that when I have seen advertisement for domes, only the size (diameter) seems to be an option, not the width of the shutter. Apparently the odd ones like you and me who like dual or triple rigs are not taken into consideration.

[tomato]

You could be right, Pulsar can supply a 2.7 metre diameter dome, I’m not sure if it comes with a wider aperture.

Maybe I could convert it into a clamshell?☺️

[carastro]

A clamshell gives a lovely wide aperture but comes with it’s own problems, as l know as l have a SkyPOD.  

ie reaching the Zenith   I had to have a POD dome table made so l slide the dome off and it is a bit of a palaver  

Carole

 

Edited August 21, 2022 by carastro

[tomato]

Maybe converting the shutter to this arrangement would be easier to implement?

[Tomatobro]

set up the EQ6-r on the garden with whatever scope you need extra?

 

 

[scotty38]

16 hours ago, tomato said:

You could be right, Pulsar can supply a 2.7 metre diameter dome, I’m not sure if it comes with a wider aperture.

Maybe I could convert it into a clamshell?☺️

100mm wider on the 2.7m

[Peter Drew]

22 hours ago, tomato said:

Maybe converting the shutter to this arrangement would be easier to implement?

I use this style for large domes, it has a number of advantages.  I built a 26 foot dome by converting a silo, this had to have a parallel aperture cut through it.  My advice? forget it!      🙂 

[Rusted]

Widen the observation slit and you have to widen the shutters too.
Widen the shutters and you have to widen the rails and increase the spacing on the rollers.
A wider observation slit does not allow larger telescopes.
Not unless you stick a large refractor out of the slit like a silly cartoon.
 

[Peter Drew]

The widening option is only viable on paper at the design stage, not retrospective.     🙂

[tomato]

Thanks for the replies and I appreciate that modifying an existing dome would be fraught with difficulties. However, putting aside the problem of how to provide a working shutter, I don’t follow that making the aperture bigger wouldn’t solve my problem. I don’t want to put an 8” F10 refractor in there, it’s multiple scopes on the same mount, as per this thread:

The scopes are in there and working, I can slew anywhere I want and they don’t foul the dome or any fixtures and fittings, there is just fibreglass in the way of the piggy backed scope when it is pointing at high elevations.

[Rusted]

Bi-parting shutters are in your stars.

I'd aim for a bigger, secondhand Pulsar.

Failing that, aim for a driven altazimuth.
Then you can stack all the scopes vertically in line with the slit.

Altazimuth on an equatorial platform? As above.

 

Edited August 23, 2022 by Rusted
Typo

[tomato]

I think I’ll follow @Tomatobro’s advice and set the third scope up on the lawn as it is only  for a trial project.