Jump to content

Mognet

Members
 View Profile  See their activity

  • Posts

    549

  • Joined

  • Last visited

 Content Type 

Posts posted by Mognet

    God Bless America!

    in The Astro Lounge

    Posted

    2 hours ago, Carbon Brush said:

    Almost all new chips produced now, and for the past decade, have been surface mount and often with sub-millimetre lead pitch.
    About the only 'inch' devices are surface mount with 1.27 or 0.05" pitch. Even they are not generally seen in manufacturers new products.

    I used to work for a solder paste stencil manufacturer and the customer designs we received were always in imperial units. Pitches were measured in thousandths of an inch at the time, the finest pitch we'd usually see was 0.008" (I think) and occasionally an experimental 0.004" for one of the universities

    That was 25 years ago and I haven't kept up with the modern practices so they may have switched to metric now. Never questioned it at the time even though the UK was already mostly metric by then. Possibly a lot of designs originated in the US?

    Tiny telescope!

    in The Astro Lounge

    Posted

    That solid Schmidt does look similar, and means that the solid telescope is not a new idea. LLNL claim to have a patent on their design, so I wonder how this would affect it. I also didn't see anything to say when Rik ter Horst had come up with his idea as it looks like he's been making them for a few years

    Tiny telescope!

    in The Astro Lounge

    Posted

    38 minutes ago, McQ said:

    Followup by the group that commissioned the tiny scopes.

     

     

    Thanks for that. It looks like they are quite capable performers, and certainly well suited to satellite and UAV use as they won't be prone to vibration related problems

    Experimental 3D printed equatorial wedge for older SW SynScan mounts

    in DIY Astronomer

    Posted · Edited by Mognet
    Found the constraints

    7 hours ago, Gasman said:

    Have you tried DesignSpark Mechanical at all? It's a freebie cad app for Windows and very intuitive. If I can learn Cad with it anyone can 😏.

    Steve

    Downloaded it last night and had a quick play. Just watched a batch of tutorial videos and it looks quite good. Only thing that seems to be missing compared to FreeCad and Fusion 360 is constraints in sketching. I initially found them frustrating, but they are also useful at times Also has constraints, which are not on by default but need to be enabled in settings

    Experimental 3D printed equatorial wedge for older SW SynScan mounts

    in DIY Astronomer

    Posted · Edited by Mognet
    Use the right code for the thread

    3 hours ago, Chriske said:

    ok, now I'v got it..!  I thought the upper grey and black part were also printed...silly me...

    That's ok. Perhaps I should have used this photo originally. It shows the whole thing with the camera too

    20210812_002308.thumb.jpg.b2cf0ebbfb1c040df179c04e3f7cee5c.jpg

    3 hours ago, Chriske said:

    Suggestion, change the threaded rod with something more stable, as Peter also explained. I'd print a wedge to fill in that gap + a little possible polar tuning. Or is there really need for that long threaded rod..?

    That rod could be a problem. I don't think it needs to be that long either, and at larger angles the mount may not be able to cope with the shifted weight. I'll see if I can come up with something stronger and more stable that can still be adjustable

     

    3 hours ago, Chriske said:

    That rod btw: nice print, very nice print indeed...!

    Thanks. I used OpenSCad for the design, and the thread uses this bit of code. It creates a 2D shape of the cross section of the thread and the extrudes and rotates it 

    module adjustment_thread(height, threadTolerance = 0) {
    threadDepth = screwThreadDepth - threadTolerance;
    innerRadius = rScrewThread - screwThreadDepth - threadTolerance;
    
    function ra(x, z) = [x * sin(360 * z), x * cos(360 * z)];
    input = [
        for (lp = [0:0.05:1]) ra(innerRadius + (threadDepth * lp), lp / 4),
        for (lp = [0:0.05:1]) ra(innerRadius + threadDepth, 0.25 + lp / 4),
        for (lp = [0:0.05:1]) ra(innerRadius + (threadDepth * (1 - lp)), 0.5 + lp / 4),
        for (lp = [0:0.05:1]) ra(innerRadius + 0, 0.75 + lp / 4)
    ];
	
    translate([0, -adjustmentBlockPlateLength, offsetToTop - bodyThickness / 2]) rotate([0, 180, 0])
        linear_extrude(height = height, twist = -(height/(screwThreadDepth*4)*360)) 
                polygon(points = input);
}

     

    Tiny telescope!

    in The Astro Lounge

    Posted

    9 minutes ago, Alien 13 said:

    I want one...

    Alan

    Same here, even if to only experiement with

    I'm curious as to how they perform. I couldn't find anything with a quick search, but if they are going to be using one in a satellite then they must perform well

    • Like 1

    Experimental 3D printed equatorial wedge for older SW SynScan mounts

    in DIY Astronomer

    Posted

    4 hours ago, Chriske said:

    Hey,

    Nice 3D-print project. Could you explain a bit more how this tracker works.
    I can't figure out how you track stars with this device(it's probably me, I know, sorry...😳)

    Hi,

    That's ok. It basically converts the alt-az mount into an equatorial mount, so what is normally the vertical axis (the azimuth axis) becomes the equatorial axis

    Alignment is crude. The camera is set parallel to the equatorial axis using the markers that were already on the mount, and then the mount is roughly aligned with Polaris. After that the handset controls are used to point the camera at the appropriate patch of sky, and the mount rotation should match that of the stars

     

    3 hours ago, PeterW said:

    I’d have designed it for a fixed angle to avoid flex and possible failure, but seems like yours is delivering the goods!   
    good job!

    Peter

    Thanks. I did consider creating a fixed angle version, which would have been fine for my use, but I wanted to share it with the community too so opted for the adaptable version. The hinge seems to take most of the weight, so I think it's fairly safe. I wouldn't trust it with anything more than the weight of my camera and 70-300 lens, i.e. less than a kilo

    Experimental 3D printed equatorial wedge for older SW SynScan mounts

    in DIY Astronomer

    Posted

    21 minutes ago, Stargazer33 said:

    Would loading the firmware for an eq mount give you the star alignment option? In effect, your mount now acts more like an eq than an alt-az.  I know Celestron hand controllers can be programmed with either firmware so I suspect Skywatcher hand controllers can too.

    Excellent idea by the way!

    Thanks

    I don't think that's an option for this mount. Certainly nothing obvious from looking at their site and I didn't see anything in the handset menu for it

    Experimental 3D printed equatorial wedge for older SW SynScan mounts

    in DIY Astronomer

    Posted

    11 hours ago, dmki said:

    This is a really nice piece of engineering. I am just starting the 3d printing  and cad journey and to be honest I didn't really think it was capable of stuff like this. something for me to aim towards

    Thanks. 3D printing is quite capable of things like this, and more too. Several members here use 3D printing for lots of things, including clocks, telescopes and rockets for display

    The biggest of the telescopes. Chriske has made several different types

    Rocket for display, also by Chriske

    And one of Gina's clocks

     

    Experimental 3D printed equatorial wedge for older SW SynScan mounts

    in DIY Astronomer

    Posted

    Hoping the skies stay clear tonight so I can test version 2

    I adjusted some of the dimensions and took out the nice curves that fitted the base as they were a bit of a pain to place properly and their positions weren't calculated. The result isn't quite as pretty but it will still work. This version was printed and set up about a month ago and there doesn't seem to be any warping of the PLA so far, unlike the previous version. There is a wobble in the adaptor which seems to be due to play in the adjustment screw and mounts. I might also need to boost the thickness of some parts too

    497699025_WedgeforSWAlt-Az.thumb.png.3226627e439c13b7ae8aeb4c8b1a9344.png

    20211015_190913.thumb.jpg.cc95f49149a8b700731e95c695aa619c.jpg

    • Like 3

    Another All Sky Camera

    in DIY Astronomer

    Posted

    Have made a minor update to take it to v1.2.6

    This time I found that surplus jpg files were not being deleted before new movies were created. I'd turned off the power here without shutting down the cameras cleanly first and a jpg file wasn't added into the daytime movie that day, but was left hanging around. That meant it kept getting added in at the start of every daytime movie as that part uses a wildcard add rather than named file. The code to clear the surplus files relied on a wildcard which doesn't seem to work with a file delete in Bash, even though it does from the command line

    • Like 1
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.