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

What did you work on today?

  • Please log in to reply
4240 replies to this topic

#2501 Andy Tucker

Andy Tucker

    Explorer 1

  • -----
  • Posts: 61
  • Joined: 05 Dec 2013

Posted 05 March 2018 - 07:25 PM

Finally finished assembling Dale's 3-axis stage. 

3axisStageS.jpg

Despite being a small project, it STILL took 2 trips for hardware!


  • CCD-Freak, roscoe, brave_ulysses and 8 others like this

#2502 Bob4BVM

Bob4BVM

    Surveyor 1

  • *****
  • Posts: 1921
  • Joined: 23 Mar 2015
  • Loc: W. Oregon

Posted 08 March 2018 - 02:10 PM

Universal lens-testing EP, to test performance of various low-glass EP candidate lenses. Two cells handle lens diameters 9-31MM, easy to change cells & lenses in the dark for OTF star-testing of single lenses & simple combinations.

More details in the EP forum.

CS

Bob

Lens-test EP1.jpg


Edited by Bob4BVM, 08 March 2018 - 02:11 PM.

  • PrestonE, Rusted, brave_ulysses and 8 others like this

#2503 arcainemachinest

arcainemachinest

    Vendor (machinist)

  • *****
  • Vendors
  • Posts: 261
  • Joined: 18 Nov 2017
  • Loc: Jacksonville Florida

Posted 09 March 2018 - 10:17 AM

mark 2 pattern for my mirror casting project

 

mirror6
mirror7

  • brave_ulysses and Augustus like this

#2504 jtsenghas

jtsenghas

    Skylab

  • *****
  • Posts: 4304
  • Joined: 14 Sep 2014
  • Loc: The flatlands of Northwest Ohio 41.11N --Bloomdale

Posted 09 March 2018 - 08:36 PM

mark 2 pattern for my mirror casting project

Looks nice! I like the large internal radii at the ends of the "spokes" or ribs, but why are they curved? I don't see a structural or manufacturing advantage to that design element. Can you explain?
  • Augustus and wna like this

#2505 arcainemachinest

arcainemachinest

    Vendor (machinist)

  • *****
  • Vendors
  • Posts: 261
  • Joined: 18 Nov 2017
  • Loc: Jacksonville Florida

Posted 10 March 2018 - 12:46 PM

 

mark 2 pattern for my mirror casting project

Looks nice! I like the large internal radii at the ends of the "spokes" or ribs, but why are they curved? I don't see a structural or manufacturing advantage to that design element. Can you explain?

 

years ago i worked in a shop where we did proprietary milling programs on solid slabs of aluminum to make money comb structures for air craft  parts. these parts all had radial style ribs. we tested the radial vs the straight on twisting and flexing the parts with the radial ribs were very hard to twist or flex.


  • Augustus likes this

#2506 mark cowan

mark cowan

    Vendor (Veritas Optics)

  • *****
  • Vendors
  • Posts: 9436
  • Joined: 03 Jun 2005
  • Loc: salem, OR

Posted 10 March 2018 - 01:54 PM

They do have more mass than straight ribs...



#2507 Oberon

Oberon

    Mercury-Atlas

  • -----
  • Posts: 2909
  • Joined: 24 Feb 2013
  • Loc: Hunter Valley NSW Australia

Posted 10 March 2018 - 05:57 PM

Yes, it is reasonable to expect that curved radial arms will improve resistance to twisting, which is important in an aircraft structure, essentially because the curved support works in two dimensions. But that improvement comes at the expense of stiffness in the direction that applies to the much simpler gravitational forces on a mirror. Or else the aircraft structure was two plates separated by a honeycomb, which is an entirely different structure, and exactly what we recommended earlier in the thread. 



#2508 Mike G.

Mike G.

    Surveyor 1

  • *****
  • Posts: 1501
  • Joined: 17 Jun 2013
  • Loc: Oberlin, Ohio

Posted 10 March 2018 - 05:59 PM

busy but productive day.  completely flocked the C6 (tube, secondary cell and baffle), then blackened the edge of the primary where the chamfer is ground.  cleaned everything up and put it outside to cool so I can collimate it tonight - looks really dark inside the tube now!  happy!  then, took the power board off my CG5 and fixed the on/off switch which had been causing some power downs during use.  back together now with no problems. just have to fix the dishwasher now before it gets dark or the wife will be unhappy....


  • Augustus and Allanbarth1 like this

#2509 Eikonal

Eikonal

    Vostok 1

  • *****
  • Posts: 174
  • Joined: 11 May 2011

Posted 11 March 2018 - 02:36 PM

I made a couple of supports for a counterbalance bar and for a finderscope.StuetzenimDrucker.jpg Stuetzen1.jpg


  • brave_ulysses, Pinbout and dmcnally like this

#2510 JohnH

JohnH

    Gemini

  • ****-
  • Posts: 3029
  • Joined: 04 Oct 2005
  • Loc: Squamish BC Moved!!!!!

Posted 11 March 2018 - 05:36 PM

Worked on getting back into shape instead of wasting time online


  • Pinbout, Eikonal, ziridava and 3 others like this

#2511 TonyStar

TonyStar

    Viking 1

  • *****
  • Posts: 584
  • Joined: 25 May 2013

Posted 20 March 2018 - 06:31 PM

I converted my GSO laser collimator to barlowed laser. I only use the laser for aligning the primary (and then fine tweak on a star) and I was tired of sliding a barlow in and out every time....

 

FullSizeRender (18).jpg

Attached Thumbnails

  • FullSizeRender (19).jpg

  • Pinbout and cmooney91 like this

#2512 Joe1950

Joe1950

    Cosmos

  • *****
  • Posts: 9439
  • Joined: 22 Aug 2015

Posted 20 March 2018 - 07:47 PM

How is that done, if I may ask?



#2513 TonyStar

TonyStar

    Viking 1

  • *****
  • Posts: 584
  • Joined: 25 May 2013

Posted 20 March 2018 - 08:17 PM

How is that done, if I may ask?

I removed the perforated aluminum block, slightly enlarged the pinhole on the back of the block and inserted a small (5mm dia) double concave lens in it. 


  • Joe1950 likes this

#2514 Joe1950

Joe1950

    Cosmos

  • *****
  • Posts: 9439
  • Joined: 22 Aug 2015

Posted 20 March 2018 - 08:20 PM

Thanks Tony. I may give it a try. waytogo.gif



#2515 TonyStar

TonyStar

    Viking 1

  • *****
  • Posts: 584
  • Joined: 25 May 2013

Posted 20 March 2018 - 08:23 PM

Thanks Tony. I may give it a try. waytogo.gif

Forgot to mention, you need to use a lens with at least 60-70mm (negative) F.L. otherwise the beam will be too spread out and the center dot shadow too dim.


  • Pinbout and Joe1950 like this

#2516 Joe1950

Joe1950

    Cosmos

  • *****
  • Posts: 9439
  • Joined: 22 Aug 2015

Posted 20 March 2018 - 08:34 PM

Okay. I'll check Surplus Shed. Thanks


Edited by Joe1950, 20 March 2018 - 08:35 PM.


#2517 Sean Cunneen

Sean Cunneen

    Let Me Think

  • *****
  • Moderators
  • topic starter
  • Posts: 3823
  • Joined: 01 Aug 2007
  • Loc: Flossmoor Il.

Posted 21 March 2018 - 09:44 AM

Okay. I'll check Surplus Shed. Thanks

 


I started this thread 3 years and one month ago, we are at 101 pages of ATM awesomeness! I dont think there has been more than a couple of days without a post! You guys make this niche of the hobby so cool, keep it up

Sean


Edited by Sean Cunneen, 21 March 2018 - 09:45 AM.

  • PrestonE, sglamb, roscoe and 3 others like this

#2518 Allanbarth1

Allanbarth1

    Skylab

  • -----
  • Posts: 4001
  • Joined: 29 Apr 2016
  • Loc: Central New Jersey

Posted 21 March 2018 - 10:34 AM

Thanks for starting this thread. It's given me a few ideas of things to make or modify. One of the threads I truly look forward to see what's posted next. 

 

Thanks


  • brave_ulysses likes this

#2519 Rusted

Rusted

    Surveyor 1

  • *****
  • Posts: 1532
  • Joined: 06 Dec 2008

Posted 21 March 2018 - 11:42 AM

It will ride up with wear, Sir! Suits you, Sir!  smirk.gif

 

P1310870 rsz 500.JPG


  • roscoe likes this

#2520 philipdo

philipdo

    Messenger

  • -----
  • Posts: 490
  • Joined: 06 Dec 2006
  • Loc: Flanders, Belgium, Europe

Posted 23 March 2018 - 11:42 AM

At our last club meeting a fellow ATM'er gave away this fully functional JMI motofocuser because of a crack in the plastic motor cover.

I took it home, replaced the cover and adapted it to the focuser of my 200 mm Kutter Schiefspiegler. I did not attach it directly to the shaft of the reduction knob but worked with a rubber belt for transmission of the slow movement. Works extremely well. It is a joy now to focus this f20 scope without touching anything and without vibration at high powers. Only drawback: since I need quite some focusing travel, when switching eyepieces, I remove the belt, do the coarse focusing by hand, put on the belt again an do the fine focusing in all comfort. Will be extremely helpful for webcamming the planets.

Attached Thumbnails

  • IMG_2860.JPG
  • IMG_2861.JPG

Edited by philipdo, 23 March 2018 - 11:44 AM.

  • brave_ulysses, Pinbout, dmcnally and 4 others like this

#2521 TonyStar

TonyStar

    Viking 1

  • *****
  • Posts: 584
  • Joined: 25 May 2013

Posted 12 April 2018 - 09:22 PM

Due to crappy seeing and bad weather I decided to take the scope apart (literally, since it breaks down to fit in a suitcase) and to paint/powdercoat a bunch of parts (long overdue). Here is the UTA upper ring painted black

 

FullSizeRender (22).jpg

 

Those vanes are thin!

 

FullSizeRender (21).jpg


Edited by TonyStar, 12 April 2018 - 09:22 PM.

  • brave_ulysses, jdupton, Eikonal and 3 others like this

#2522 ImNewHere

ImNewHere

    Vanguard

  • *****
  • Posts: 2145
  • Joined: 29 Mar 2017
  • Loc: Nashville, IN

Posted 12 April 2018 - 09:27 PM

Finished my SN10 rebuild other than final collimation tweaking and touch up paint in a few spots.



#2523 Andy Tucker

Andy Tucker

    Explorer 1

  • -----
  • Posts: 61
  • Joined: 05 Dec 2013

Posted 12 April 2018 - 10:35 PM

I printed a holder for 1.25" filters to fit into a UV/Vis spectrometer the other day.  Today I tested a cheap filter:

EPfilterHolderSmall.jpg

 

 

SVBONYspectrumSmall.jpg

 


  • PrestonE, brave_ulysses, Eikonal and 2 others like this

#2524 roscoe

roscoe

    curmudgeon

  • *****
  • Posts: 10301
  • Joined: 04 Feb 2009
  • Loc: NW Mass, inches from VT

Posted 13 April 2018 - 06:49 AM

wouldn't it be wonderful if we all had access to real test equipment??   (I'm jealous!)

No more....I think this is a little yellower than that one, or I think this one scatters more than that one, just stick it in the magic box, and....yep, this diagonal's mirror is smoother than that mirror...or whatever.....



#2525 Oberon

Oberon

    Mercury-Atlas

  • -----
  • Posts: 2909
  • Joined: 24 Feb 2013
  • Loc: Hunter Valley NSW Australia

Posted 13 April 2018 - 07:03 AM

Due to crappy seeing and bad weather I decided to take the scope apart (literally, since it breaks down to fit in a suitcase) and to paint/powdercoat a bunch of parts (long overdue). Here is the UTA upper ring painted black

 

attachicon.gif FullSizeRender (22).jpg

 

Those vanes are thin!

 

attachicon.gif FullSizeRender (21).jpg

Beautiful and elegantly engineered. Everything is just right.


  • TonyStar likes this


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.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics