I attached keepers 1 inches wide by 5 inches long, extending above the bottom of the arcs by about 1 inches. After the glue dried but before the clamps were removed, I added corner braces to all four corners of the tube using glue and brads to hold them in place. Nice looking telescope. I found out pretty quickly that building my own telescope would only be a bargain if I made my own mirror and mechanical parts. Part numbers 351-4574 and 336-422. A week after they said they would send the secondary and other parts, I called to ask if things had been sent. But, like many of you I'm sure, the biggest reason I'm doing this is for the pure geeky fun of it! In my build, the minimum eyepiece-to-secondary mirror distance (13) plus the primary-to-secondary mirror distance (57) equals the focal length of 71, which is roughly 4.5 times the width of the 16 mirror. In addition, we use third-party cookies to help us analyze and understand usage. To interface with the computer, I have used the Artemis Focuser module from Steve, Arthur and Co. and an eyepiece. A Pocket Sundial From a Broken Pocket Watch! Line the underside of the rocker box with a ring of ABS plastic to allow it to ride on the base. I drew a guide line straight down the side of the tube and cut the veneer to length with one extra inch on each side68 inches long. control. : "http://www. This makes for better sky photographs as the exposure time can be lengthened,. Share it with us! So I was looking for a cheap, light-but-sturdy design for a I read the entire thread and surely its going to help me building my focuser. Rather than use a sheet of plastic Kydex to finish the tube, as recommended in K/B, I ordered a sheet of birch veneer. I have already seen some designs on CN, Stellafane and web but still checking if someone has recently made anything simpler. Rock Paper Scissors Using Tinkercad Circuits and Arduino, Punchy the MECH & the Autonomous Fight Club, Soft-sensor-saurus | an E-textile Soft Sensor Soft Toy With LED Light. The holes in the main bracket the match the holes in the plate are oversize to allow for this alignment. small, it's surprisingly rigid. document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E")); weight. Cost is $25 - $30, and you will have 5 PCBs in about a week. The blue pieces of the rocker box and ground board are arranged as in the diagrams in (figure 2). It had been described by many as the most important recent volume for anyone planning to build a dob, and I have to agree. It may need some careful coaxing with a screwdriver. Once built, line the undersides of the arms with textured ABS plastic as a bearing surface. This one is based on the DRV8825 driver chip and a NEMA-17 stepper motor. (Sorry you The only thing on the list that was a bit difficult to find was baltic birch plywood, which had to be special ordered from the lumber yard. on Step 5, 9 years ago My guess is that photo was taken with a refractor. Before attaching the sides and front to the bottom with wood screws, I wanted to make sure those screws would not interfere with the Ebony Star ring that would be attached to the rocker bottom. To test the concept I used a short piece of two inch PVC for the draw tube. For my project I needed a 14 inch diameter, and I had a tough time finding one. Step 3The Side Bearings and Rocker Sides. The motor is much lighter than the geared motor. adapter set screws to slide into. The version number "312" here may change if Robert posts new firmware. Thicker knitting needles would be even Here is what I was working on but looks like I need a better design. Finally, attach your polar alignment device and align it with the hinge. The focuser knob had two set screws. narrow the frame. (The 8 inches from the center of the secondary to the field stop in the focuser is the same 8 inches from the center of the focuser to the top of the tube.) Realizing that it could not be the University Optics cell already, I thought, Noit couldn't be but, in fact, it was. They have many items for ATMers and I had frequently visited their website when planning my scope. Make the drawtube longer than you think you'll need, just in a "rubbery" feel. To view, go here: http://emediadesigns.com/focuser/ Here is a simple 3D printed helical focuser that cost just a few cents (assuming you have a 3D printer). I'd be willing to bet that you could easily grind your own 12.5 inch next time and save some $$. So I decided to make my own, using my normal "blunder in naively and see what happens" approach to making things. I wanted a tight / press fit, so I only added half that, 0.25mm. Finally, I attached Keepers to the sides of the rocker at the bottom of the arcs using screws and glue. Edited by sunrag, 28 May 2020 - 10:44 PM. The mirror box encloses the mirror cell and allows the entire telescope to rotate vertically. A week after they said they would send the secondary and other parts, I called to ask if things had been sent. Start with the small components first. Given any mirror measurements, PLOP will provide the ideal support layout and how much distortion to expect for any number of flotation points. I also have an extended photographic build diary of this telescope posted on Imgur. A few months later I ordered some other things from Scopestuff, including strips of Ebony Star laminate for the side bearings, a ring of Ebony Star for the rocker bottom, a strip of teflon to cut pieces for the ground board and side bearings, and a new base for my Telrad finder. That evening I spent most of my time rediscovering the many DSOs around Sagittarius, especially the Lagoon Nebula and the Trifid Nebula. my 12.5" trackball, but I didn't Along with some silver bits Parts List (the full story of acquiring the parts), The primary, secondary, spider and secondary holderDiscovery Optics. Their step by step instructions were invaluable to me as I built this scope. I started with a spacer that with a inch outer diameter. Again from the main FILES page, go to "ASCOM DRIVERS" and download everything. To place the primary mirror, I installed the secondary and installed the primary in the mirror cell. However more than the focuser, I liked your scope. It took about 3 weeks but, since Anttler's did not even reply to the Paypal dispute, I received a Paypal refund. If you're not familiar with Arduino, watch some tutorial videos. After picking up a copy of The Dobsonian Telescope by David Kriege, I built my first telescope with a 12-diameter mirror, then later tackled a 12 lightweight scope. Unbelievable! Another vote for Pierre's helical Crayford design. tube and nut that fits the outside threads. PVC pipe makes great drawtubes. Make an account on JLCPCB.com, upload the Gerber zip file, that's it! As I mentioned on my binocular Our websites use cookies to improve your browsing experience. If you connect the 12V power with the barrel connector (right side of photo), the Nano should light up without the USB connection. var pageTracker = _gat._getTracker("UA-1008534-4"); The diameter of the focuser is usually indicated in inches. At some point in the building process, my goal became to finish the scope by RocheStar Fest, an annual event of the Rochester Astronomy Club. I started by trying to drill out a metal gear for the focuser shaft. Edited by Pierre Lemay, 25 May 2020 - 08:10 AM. i got a email that someone built a telescope close to mine that has seen the stuff in the photos here is a link to his site http://www.synapticsystems.com/sky/scopes/Dob.htmlif i seem a bit rude please forgive me i just spent 12hrs in a plane i have jetlag and im sitting in a airport.i would like to thank lvlasertech for keeping this instructable lively and informative. can't click on it or copy and paste it; it's a graphic file to thwart spambots that search the internet for addresses to send junk mail to.) 24 T-nuts, with matching 2 bolts and knobs, 8 Aluminum tubing, thin wall, 1 square, 4 lengths I got mine from Cycle 24, Black woven velveteen, 68 Cut it so it stretches along the 6 axis. I then ran a bead of glue on the mark, and after it dried I cut out the nylon up to the glue. in the tube so they'll hit the knitting needle before your drawtube runs Since there is no drill bit that exactly matches the 13.1mm of the shaft, I had to do some rough enlargement of the hole. microcontrollers including Arduino and Raspberry Pi, Drones and 3D Printing, and more. After a dry fit of the rocker to make sure that the tube box with side bearings would fit well, I glued the rocker sides to the rocker front, holding them in place with small nails and clamping overnight. We are now ready for some testing. A project collaboration and documentation platform. I used my router to "mill" a flat area for better contact with the focus adjustment rod. At this point, the scope was pretty much finished. We all know the problems with focusing. The telescopes size is classified by the size of its mirror. On the cutting diagram, you can see that the side bearings were cut 26 inches long. The silly colours are mainly due to me experimenting with various clothes dyes in the anodising. Electronics and software automate the process of taking pictures. I redrilled the holes for the mirror cell and got ready to wrap it. Newton, and others including James Gregory and Laurent Cassegrain, believed that a reflecting telescope would not be affected by the chromatic aberration that affected . Use the externalMirror Edge Support Calculatorto decide whether to use a two-point, four-point (whiffletree), or sling support. It has become an indispensable piece of equipment for me that so beats hacking and filing PVC pipes etc. So, as they say, "back to the drawing board". . The next day my wife called me at work to tell me a box had arrived with telescope stuff. This means I can use FocusMax to do the focusing. The cutting diagram in (figure 1) shows how I cut the required pieces from two 60 X 60 pieces of Baltic Birch plywood, one inch thick, and one 5/8. I gave them a call and they said they had one on the shelf14 inches in diameter and 12 feet long! Sh2-169 and Sh2-168, IC5146 Cocoon Nebula, Caldwell 19, Sh 2-125. 4 years ago My secondary is 4; for tips on choosing size, click here. Plan ahead by carefully weighing all components and approximating the center mass of the optical assembly. I did not wrap the tube until I had completed the base. Thanks for the great comment. flexing. I made a similar helical focuser with a nice 2 inch thing I found in Classifieds. This is the kind of simple off the shelf design I was looking for. I marked the expected position of the secondary by measuring 61 inches down from the end of the tube. This sure is going to be a project I will work on. I had chosen a boxy, rigid design for the binocular scope, so on Step 1, Richards in our local astronomy club. the side of a rigid secondary cage. Once its cut to length, drill a hole through each end of the tubing with a drill press. This is because my router bit was inch and the arc would be cut by the outside edge of the bit (where the circle had been cut by the inside edge.) The focuser is the part of the telescope that holds the eyepiece or camera, and by moving in or out, closer or farther from the . This consists of a small black box of electronics. Be creative! The premier publication of maker projects, skill-building tutorials, in-depth reviews, and inspirational stories,
I decided to use baltic birch because it is recommended by Kriege and Berry as well as many online sources. homemade Crayford focuser. This NEMA-17 direct drive stepper motor is available from Adafruit and many other sellers. There are some test sketches in the "Tests" folder, start with those. The Crayford focuser is a simplified focusing mechanism for amateur astronomical telescopes. The hole did need to be enlarged slightly by moving the bit within the hole , but in the end, the fit seems right. until a 2" eyepiece or 1.25" adapter is snug. Your choice here will be recorded for all Make.co Websites. I attached three feet equally spaced on top of the ring, and on the opposite side attached teflon pads 1 X 1 directly above the feet using very small brads and countersinking the brads below the surface of the teflon. There was the expense, for one, but also the In order for the Rocker Box to pivot on the Ground Board, a center pin is placed in a hole at the exact center of the Ground Board and Rocker Bottom. The flat wants to be running parallel to the long axis of the tube. And the legs of the base should be as wide as possible to accommodate weight imbalance as the telescope is moved around, to avoid tipping. You will need to remove the regular focus knob on your telescope's focuser. If you want a Crayford focuser with a knob instead of turning the draw tube, then Jerry Oltion's designhttp://www.jerryoltixycrayfords.htm using box frames and knitting needle drive shafts is also a fairly easy build. You can easily, and economically (10$) build a Crayford Helical Focuser like the one pictured above in one evening with simple tools. rod for the drive axle it would have a fairly fine motion. Just as it was about to come into focus, the focuser bottomed out. If you enter it in the next contest please let me know and i will make sure to vote for you. I drilled the holes in the center of the ground board and rocker bottom using a 9/16 bit, thinking that I needed the extra 1/16 so that the spacer could move. love to hear from people who are interested in this focuser design. Or in my case, back to SolidWorks :-). I had the thought that as long as I was going to build it I should build it as big as I could afford. widening the hole. Dobsonian telescopes are popular with amateur telescope makers for their ease of design and construction, portability, and their use of large optical mirrors. I then attached the Ebony Star ring using contact cement. Share it with us! once. Similar photos at http://www.telescopegeek.com/gallery.htm require 100+ minute exposure times on his 20" telescope and $3200 camera. I brought a saw with me so that I cut it in half to fit in my minivan. For the ATMer I do find that there are an endless number of parts that can be designed and printed for home built telescopes and binoscopes. This is the first telescope that I have built. Link to the motor speed controller kit:http://www.jaycar.com.au/productView.asp?ID=KC5225(a 5K external potentiometer will be required): http://www.jaycar.com.au/productView.asp?ID=RP3508The drive motor:http://www.jaycar.com.au/productView.asp?ID=YG2734The gears:http://www.jaycar.com.au/productView.asp?ID=YG2736The motor forward/reverse switch:http://www.jaycar.com.au/productView.asp?ID=ST0506The push button:http://www.jaycar.com.au/productView.asp?ID=SP0711 To get this arc, I actually moved the radius of the jig, At some point in the building process, my goal became to finish the scope by RocheStar Fest, an annual event of the. At their suggestion, I also ordered a 2.6 inch secondary mirror. This project is based on Robert Brown's "Arduino ASCOM Focuser Pro2 DIY". Share it with us! In order to check your measurements, you can construct jigs for your mirror cell and secondary cage, positioning them on a straight, adjustable track such as 2 planks of wood. try { a try. Interfaced with a computer, so the computer can make the decisions about where the best focus is. Here is a link to the main FILES area on Robert Brown's site. The focuser 'knob' on the Celestron is just a rubber sleeve that usually pulls off easily. Telescope Magazine. As it turned out, the mirror cell was too large to fit into my 14 inch sonotube. When the skies were dark enough for observing I found that the scope moves easily into position and holds that position well. A couple setscrews and you're up & running with an off the shelf solution. You simply glue or screw the 'nut' part to your scope OTA, and thread the tube part in/out to focus. This motor has a 5mm drive shaft. 11 years ago stronger, but would give me a coarser focus action because of their Tips If you've got a 1.25 inch focuser, You can also use it for an objective. My DIY Motorized Telescope Focuser - YouTube I use a 3D printer and an old gear motor to create an electronic telescope focuser.This is my first attempt at voiceover, I'm using a headset. Frustrated by these difficulties, I stopped by one more hardware store to ask for advice. This will determine the size of the coupler you will use to connect the stepper motor. And a flat thing to put it all on forward and back along with the drawtube when you focus, and you'll get I marked the spot and moved things back inside to install the mirror. The basic points I wanted to cover: What did I end up with? I have seen some VERY impressive photos similar to those, taken with Nikon D700 and D300 cameras, with the proper filters- and mounts- on a quality scope. I phoned in the order in the last week of February and was told that it would take about 4 weeks to deliver the mirror. The secondary holder is adjustable, so I could didn't have to get the location perfect. on Introduction. The balance point determines the height of the rocker sides, so I had to get this far before I cut the wood for the base. Most people will want a knob on Able to shift heavy loads of kit ie over 1000g. The rocker arms must also have guides to keep it on the track; flat metal 12 braces lined with ABS plastic work nicely. Coupler for NEMA-17 Stepper Motor (also two choices, see below), LM7808 Voltage Regulator with TO-220 package -, Mini On/Off 3-pin 2-position slide switch -, Headers and wire (miscellaneous sizes and gauges), these are important so you can replace the component if it is damaged, LM7808 voltage regulator w/TO-220 heat sink package, 2-pin headers for 12V power and on/off switch. Concluding that I would not be able to buy a tube off the shelf, I found a couple of companies that took special orders on cardboard tubes. I set things up in daylight and collimated the scope. All Orion 1.25" and 2" telescope focusers are engineered to provide smooth drawtube action to ensure you hit the exact focus point . The cell from Anttler's, for which I had received a refund, had arrived. After another 3 weeks, I was concerned that I had not received the mirror. This is the mirror box for my 16", with Jim doing a bit of cleanup sanding. Ideally, the spacer would be 1 inch long and have a smaller diameter, but I didn't get this one right the first time. Here are a few photos of the "bracket", which is a simple 3D printed plate that mounts to the telescope's focuser ring, and serves as a mount for the stepper motor. They even offered to send the spider, secondary holder, and secondary mirror immediately so that I could begin working on the tube while I waited for the primary. It interfaces to the computer via USB and comes with an ASCOM driver. Download the Gerber Files. The lumber yard also gave me a lower price than I expected. Perfect for visual observations with very heavy mirrors. My other telescope is a Celestron NexStar C6E. I made this Crayford style focuser using plywood scraps and surplus bearings. The core of the telescope, the steel mirror cell holds and adjusts the heavy, curved primary mirror. After cutting the circles for the side bearings, I set up the jig to cut the curved edges of the rocker sides. I pointed it at distant trees and had no problem bringing the image into focus with all of my eyepieces. The focal length of the mirror is 61 inches. You currently have javascript disabled. Now attach the screw eyes and the rubber band on the side of the board. I hate focusing. The focuser shaft on the telescope is 13.1mm in diameter. it sticks into your light path. They're fairly I am a retired USAF electronics engineer, and might even do much of the construction of the base with welded structural tubing, as, I do have a complete metal working shop besides my wood shop, here. Once I had my design set, I was ready to buy the parts. Once the pieces were cut and I held them around the tube, I decided to cut them a bit smaller because the extra space was too much. I told them to take their time and get it right. Trim off any unused fabric along the base. Place the focuser, draw the position of the screws with a pencil and remove the focuser. After the pieces were glued together, I used a belt sander to smooth out any rough edges, being careful to keep both rocker sides and both side bearings exactly the same. Please re-enable javascript to access full functionality. By adjusting the bolts, the mirror can be pointed toward the correct spot. installations. Crayford-style design with four bearings and one driveshaft. It is size 1.25 inch with a clear inside dia-meter. Pierre's Helical Crayford gets my vote hands-down for elegant simplicity. Well, it sort of looks like a focuser.. See pictures below. We use cookies to continuously improve our websites for you and optimize its design and customization. What materials did you use? Once I decided to build a scope myself I had to decide on the aperture of the scope. Thanks again for the 'ible. Also no obvious diffraction spikes in the m31 photo. on Introduction. I used one of these scrap pieces to draw an angle of 70 degrees to the edge of the arc so that I could later place the teflon pads on the arcs. Although they don't usually sell these parts, because I had ordered the mirrors from them they offered to sell me the spider and secondary holder that they use in their scopes. Since my focuser shaft is 6mm, I ordered the coupler shown here in the 6mm to 8mm version from Amazon. The wide square footprint would make it pretty stable when mounted to Very simple and portable. I ground and figured the mirror with little troubles, making my focault tester, etc. The last time I checked, that particular SBIG camera used on TelescopeGeek had an eight month lead time.A 20" scope gathers 2.6 times more light than a 12.5" scope, therefore equivalent exposures on this one would take 200+ minutes, at least. After waiting for the contact cement to dry to the touch, and with my wife's help, I carefully aligned the edge of the veneer with the guideline on the tube and pressed the first inch together. Gift the gift of Make: Magazine this holiday season! From everything I had read, I expected that getting a sonotube would be as easy as running to any hardware store and picking it up.