Friday, April 22, 2016

The Magic of 3D Printing

I remember seeing a show on the Science Channel some years ago about 3D printing. It did indeed seem like magic to me at the time. They appeared very similar to the CNC machines that I was familiar with, but instead of removing material from a block of aluminum or steel, these things actually build things from a spool of material. Fast forward a few years and now I'm seeing the near limitless capabilities from this wonderful invention.

Charles (Chuck) Hull, co-founder, executive vice president, and chief technology officer of 3D Systems created the first 3D printer in 1983, and he has been refining his invention ever since. This solid imaging process known as stereolithography (3D Printing) is the first commercial rapid prototyping technology that is now available to the masses.

This process has really blossomed over the last few years. There are a few companies now offering personal 3D printers, and I have looked into getting one for myself. Some are very reasonably priced, and you are limited only by your imagination in what you can create. Well, and maybe by the size of your machine, but thats just a minor detail.

I'm lucky enough to know a few guys through my astrophotography hobby that happen to own a 3D printer. In a very short time I have seen just how useful these machines can be. I was reacquainted with the technology about a year or so ago, when some of us were seeing what we described as an "iron cross" artifact on bright stars when imaging with our William Optics Star71 telescopes. Some examples of the scope are worse than others, and the problem seemed to be worse in cold weather. A couple of the guys made a simple aperture mask that slipped over the dew shield and it seemed to fix the problem.

My friend Josh Smith sent me one of these to try out on my scope, and the results were clearly better with the aperture mask in place. My scope as delivered was much better than some I had seen, but I still did not like the artifact. You can see the difference it made with these test shots on the star Vega.

5 second luminance, without aperture mask

5 second luminance, with aperture mask
Josh later took this a step further. The dew shield of the Star71 is very short, so he incorporated a removable mask inside of an extended dew shield. The aperture mask snaps in and out for those wishing to only use the aperture mask on cold nights, when the artifact is much worse, but take advantage of the extended dew shield year round.


Another nice touch is the bahtinov focus mask. I prefer to just leave the aperture mask/extended dew shield on the scope all the time, so he even made a dust cover for me.




mask/shield w/bahtinov focus mask
Dust cover
If you've been following along, you know that Little Piney Observatory was lucky enough to get a new equatorial mount a couple months ago. I now like to keep the Star71 piggybacked on the TS 107mm triplet, but this presented a slight problem when it came time to take a set of flats for the little scope.

I have found the longer I can expose the flats, the better results I see. I also like to place at least one sheet of plain white paper on the scope, and lay the light directly on the scope with it pointed at zenith. To do this on the Star71 using my Spike-A flat fielder, this meant removing the dew shield of the 107mm and sliding the Star71 forward so the light could lay across both telescopes. This was a bit more hassle than I wanted to fool with, so I contacted my friend Josh again to see if he might have a remedy for this situation.

What he later sent me was the perfect solution. Using his 3D printer, he fabricated a frame around the light panel that slides directly over the dew shield. When in use it easily clears the dew shield of the 107mm, and the light came with a dimmer switch. Problem solved! I was also told that he's currently working on a USB controller for the light panel. You know that I'll be calling him to see when that will be ready!





Needless to say, he has one happy customer here at Little Piney Observatory. If you have some similar needs, or just a idea in your mind, get in touch with Josh. He's an engineer by trade, and shares my love of the night sky and astrophotography. You can get in touch with him through his website at www.catchingthecosmos.com. Be sure and check out some of his amazing images while you're there.

Some other neat things to come from 3D printing are these ringed standoffs from my friend Tony Akens. These simple rings work great for keeping wires out of places they dont belong, and also make a convenient place to tie off other wires when not in use.


Tony is another great guy that just did some upgrading to his 3D printer. He says he's looking into other cable routing ideas, and I'm wondering what he will dream up next! Tony is a regular on the Cloudy Nights forum, and anyone wishing to contact him can do so here. You need to be a member of Cloudy Nights to contact him there, so if you aren't already a member, be sure and sign up today. Its free to join and there's a wealth of information there. Another plus from being a member is 5% off any purchase from the forum sponsor, Astronomics!

Enjoy the warmer Spring nights while you're out under the stars, and be sure to let me know about the 3D printing ideas you've dreamed up. If its top secret, I'll understand, you can trust me. ;)

Clear skies, and happy imaging!