Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

18 Point Flotation Mirror Cell question

  • Please log in to reply
8 replies to this topic

#1 ruachsheavens

ruachsheavens

    Apollo

  • *****
  • topic starter
  • Posts: 1307
  • Joined: 17 Jul 2005
  • Loc: Northern IL

Posted 11 January 2017 - 04:16 PM

I've seen some of these cells with an inner circle seemingly designed to keep all the triangles  in a certain position - other 18 point cells don't have them. Is that because they are nice but not necessary? or is there some other reason?

 

pis enclosed for examples -  jp astrocarft and JMI - both well known makers of good quality equipment - do not use them on their 18 point cells

 

thanks!

Attached Thumbnails

  • jp astro.jpg
  • jmi cell.jpg
  • cell with.jpg


#2 Pinbout

Pinbout

    Hubble

  • *****
  • Posts: 17052
  • Joined: 22 Feb 2010
  • Loc: Montclair, NJ

Posted 11 January 2017 - 04:45 PM

jp's doesn't need them, the other 2 look like they do.

 

the ring helps keep the supports in their proper location.

 

jp's can't rotate out of position, the other 2 can.

 

 

on my bars for this simple cell I have pins on thru the bars to keep them in place, they would be able to move all over the place without them. this is a strategy I got from phillip strock's suitcase design. you could do the same for the triangles to bars.

 

https://www.youtube....h?v=kdMofIELVd0


  • dave brock and sopticals like this

#3 dave brock

dave brock

    Apollo

  • -----
  • Posts: 1052
  • Joined: 06 Jun 2008
  • Loc: Hamilton, New Zealand

Posted 11 January 2017 - 05:23 PM

JP's have pins to stop rotation.

I think the second one is designed to be siliconed to the mirror.

 

Dave



#4 ruachsheavens

ruachsheavens

    Apollo

  • *****
  • topic starter
  • Posts: 1307
  • Joined: 17 Jul 2005
  • Loc: Northern IL

Posted 11 January 2017 - 05:34 PM

ok thanks guys



#5 ruachsheavens

ruachsheavens

    Apollo

  • *****
  • topic starter
  • Posts: 1307
  • Joined: 17 Jul 2005
  • Loc: Northern IL

Posted 11 January 2017 - 05:35 PM

do they roate with the mirror on them, or is it just to stop rotation when you are placing the mirror in the cell?



#6 Pinbout

Pinbout

    Hubble

  • *****
  • Posts: 17052
  • Joined: 22 Feb 2010
  • Loc: Montclair, NJ

Posted 11 January 2017 - 06:29 PM

When mirror is placed



#7 ruachsheavens

ruachsheavens

    Apollo

  • *****
  • topic starter
  • Posts: 1307
  • Joined: 17 Jul 2005
  • Loc: Northern IL

Posted 11 January 2017 - 06:33 PM

ok thanks



#8 ctcables

ctcables

    Messenger

  • *****
  • Posts: 442
  • Joined: 14 Nov 2006
  • Loc: Oregon

Posted 11 January 2017 - 07:27 PM

this is a great read take a look. http://www.loptics.c...rorsupport.html


  • jtsenghas likes this

#9 Pinbout

Pinbout

    Hubble

  • *****
  • Posts: 17052
  • Joined: 22 Feb 2010
  • Loc: Montclair, NJ

Posted 11 January 2017 - 09:17 PM

ok thanks

Oops I re read . they can rotate anytime, that's y ya need to stop them.




CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.







Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics