I tried all of my other eyepieces and found that I could bring the image into focus in the other eyepieces, but it was very near the bottom of the focuser travel. After the second call, I received a response that it would be ready at the end of the following week. I found a used 16 primary on eBay. When the skies were dark enough for observing I found that the scope moves easily into position and holds that position well. I decided to order an aluminum mirror cell from University Optics instead so that the mirror could be supported at 9 different points. haven't yet found any design elements that need improvement. One of the neat things about the square design is that the If you are (for example) doing a focuser for a catadioptric telescope like a Celestron C-8 or similar, the focus knob has no load on it so this smaller, lighter motor will do the trick. If you connect the 12V power with the barrel connector (right side of photo), the Nano should light up without the USB connection. This unit takes signals from your computer and drives the stepper motor on the focuser. telescope page, I wasn't really eager to buy two commercial Crayford Frustrated by these difficulties, I stopped by one more hardware store to ask for advice. on Step 1, Richards in our local astronomy club. It would cost less and they have a very good reputation. 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. Just to make sure I liked the stain, I applied some to a piece of scrap wood. Thanks again for the 'ible. I called in the order and explained that I would be using a mirror two inches thick. I want to put my 12.5 mirror in a collapsible structure so I can haul it easy, Say a truss tube design, 7 years ago Next, attach the eyepiece and the focuser to the top part of the telescope tube. Built one of these http://emediadesigns.com/focuser/ working really well only cost less than 40.00. off the bearings. I didn't receive any confirmation email after a few days, so I tried to send them an email. Thicker walls also required thicker side bearings so that the outside of the bearings would line up with the outside of the rocker sides. I had considered a Moonlite or Featherlite focuser, but I knew from my experience with my 6 inch scope that I wanted a 2 speed focuser, and the price tag of their 2 speed focusers scared me away. 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. Make an account on JLCPCB.com, upload the Gerber zip file, that's it! Telescope Magazine. Once you get it working, there's some calibration you need to do. Put it all together 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. My guess is that photo was taken with a refractor. on Introduction. Both cameras have fairly small megapixels by todays' standards, and are certainly obsolete, but do the job extremely well! Save over 40% off the annual cover price for a full year (4 issues) of Make. 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 interfaces to the computer via USB and comes with an ASCOM driver. The focal length of the mirror is 61 inches. The arc at the top of the sides needed to have a radius 1/8 inch larger than that of the side bearings to account for the thickness of the teflon pads that would fit between. var pageTracker = _gat._getTracker("UA-1008534-4"); This arrangement turns 100% true, no wobble. #@$%^#@!!!!! pageTracker._trackPageview(); I For my project I needed a 14 inch diameter, and I had a tough time finding one. I like the old way of using stepper motors and other stuff introduced years ago by Mel Bartels, he is a master for me. 11 years ago As I read the book I decided that I should build a 12.5 inch truss tube scope. They use a simple plywood mirror cell, stating that for an 8 inch mirror this cell will be adequate. small, it's surprisingly rigid. Pioneered by John Dobson in the 1960s, the instrument combines a Newtonian reflector telescope with a unique two-axis movable base. During on-site assembly, attach each truss to its mounting T-nut using a bolt with a thumbscrew knob. Two different construction supply companies told me that sonotubes were not available with a 14 inch diameter, even by special order. Once your telescope is assembled, drape black woven velveteen around the truss assembly, clipping it with safety pins. Given that you can make the drawtube any length you with a genuine question or comment about the design. Here is what I was working on but looks like I need a better design. You can see that my Moonlite focuser was slightly larger than the sides of the tube. I told them to take their time and get it right. I added three inches for a margin of error and in case I need to rebalance the tube in the future, making a distance of 25 inches from the balance point of the tube to the rocker bottom. Robert is a super guy and more than willing to help those who choose to follow in his footsteps. The dimensions of the Tube Box Sides are based on the outer diameter of my tube14 3/16. the drive shaft close against the drawtube. But who cares, really? When you figure out This is the upper tube that contains the flat secondary mirror, Telrad finder, and focuser. I had already made a lightweight focuser for My homemade motorized telescope focuser for Celestron C8. the tube is cardboard as well, you can also get a quality mirror at telescope.com for much cheaper. The flat wants to be running parallel to the long axis of the tube. Headers for the LEDs, buzzer (2-pin) and temperature probe (3-pin). Here's a detailed response from a thread at CloudyNights:http://www.cloudynights.com/ubbthreads/showthreaded.php?Cat=0&Number=4721255 "The image scale is wrong on the M31 image, fits too much of the galaxy in for even a 35mm chip. Or rather, I hated it. } catch(err) {}, SH-232 Sharpless sh-232, sh-231, sh-233, sh-235, NGC2174 Monkey Head Nebula, Sharpless 252, Sh2-252, HDW3 Hartl-Dengel-Weinberger 3 PN G149.4-09.2, SH-198 Sharpless 198, Soul Nebula, IC1848, NGC281 IC11, Sharpless Sh2-184, Pacman Nebula, SH2-173 SH2-173 Phantom of the Opera LBN 593, SH2-168 Sharpless HII regions. Their step by step instructions were invaluable to me as I built this scope. So, for my telescope I used a 6mm to 5mm coupler available on Amazon. While round tubing is sturdy, square tubing is easier to work with. A wide hole will let the knitting needle creep You will have to line up the diagonal and primary so that you see a centered image of the sonotube opening and the spyder in the eyepiece hole. Pierre Lemay, thanks for sharing your simple and incredible design. You need some purple bits It took a lot longer than I expected to receive my mirror and other parts from Discovery. I was inspired to build telescopes during a trip out to McDonald Observatory in west Texas, where I saw a 36 fork-mounted telescope, tiny in comparison to the huge research telescopes at the site. I would love to see your build when you are finished with it . But by this time I had thought about building my own scope for several weeks, and getting one off the shelf seemed pretty boring by comparison! I used a hole saw to cut a wooden plug to fit inside the Along with some silver bits If you go to buy all of the components for this project from dealers, you will see that you mostly have to buy at least 5 parts, sometimes bags of 50 parts! A 10 inch scope would not be very much longer or heavier than my 6 inch, yet it would allow me to see much more. Drawing lines between opposite corners of the tube box sides allowed me to locate the center point on each side. The mirror cell: University Optics (eventually). Among amateur telescopes, the most common are focusers with landing diameters of 1.25 ", 2", rarely 0.965 ", and even less often - 3". The Artemis module works extremely well, and is to be strongly recommended. Once I had my design set, I was ready to buy the parts. That way you won't be dropping your drawtube and It turned out that they had an incorrect zip code and the package was still waiting to be sent. There are some test sketches in the "Tests" folder, start with those. I am thankful to enjoy the inspiration, and the details, that you provide, as I will soon be constructing a Dobsonian Telescope. You will look through these as you rotate the wheel. My newtonian telescope, like most others, came fitted with a nasty rack and pinion focuser. You will need to order one sized for your telescope's focuser shaft size. I plan to use an FTA over it in case an extension is needed. I decided to order a mirror cell from them because the owner had talked about a new cell he was excited about. It The box should be deep enough to allow the mirror box to swing all the way down. needle adds no friction that I can feel to the focus action. Interfaced with a computer, so the computer can make the decisions about where the best focus is. on Step 5, After much debit and doubt i have taken the photos down cause i cannot be 100% sure that they were taking from my scope as i was not there to verify them and i do not want my contest entry to be based on photos and not the build process. Lining up this center point with the center of the top of the side bearing, I brought the corner of the side bearing up to the edge of the tube box and attached it with screws. I placed my telrad, optical finder, and an eyepiece on the focuser end of the tube and, using a broomstick as a balance point, found that the tube balanced 22 inches from the bottom. Once built, line the undersides of the arms with textured ABS plastic as a bearing surface. The day I received the refund, I ordered a mirror cell from University Optics. But -- you have to be careful that the mechanism is true and the motor does not have a load on it at any time, otherwise it will 'stall' and stop moving. The telescopes size is classified by the size of its mirror. The next day, I called back to ask their opinion about the kind of spider and secondary holder to order. While I will freely admit that most astro-photography is WAY beyond me, you certainly do NOT need a $3200 camera to do so. I sourced my own Stepper motor and 1:150 reduction gearbox from RS, who are just up the road. Im sorry to hear you couldn't make the contest. I did not glue the bearings to the tube box in case I needed to adjust the position later. To test the concept I used a short piece of two inch PVC for the draw tube. Low, or Zero slop when changing direction. If the telescope rotates forward or backward on its own, then the mirror box is too deep or too shallow. Now I can simply insert the PVC cap on the end of a 4" pvc tube. It's the same in form, but has a perfect, true 13.35mm hole. The wood would cost the same, as would pretty much everything except the mirror, so why not spend a little more on the mirror and go BIG. I file a dispute with Paypal to begin the process of getting my money back. Brandon Lawler is a hobbyist telescope Maker and an active member of the Central Texas Astronomical Society. We were careful to press out any bubbles as we went, but when the job was done we found that there were multiple bubbles in the veneer. A couple setscrews and you're up & running with an off the shelf solution. To glue the side bearings and rocker sides to full thickness, I covered a side with wood glue, then carefully lined up the pieces and put two small nails into the pieces to hold them in place. This allows for a small clearance between the outside of the tube and the inside of the tube box (14 3/8). But I wanted a larger mirror, and, at that size, grinding my own was not an option. 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. 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. It takes the unknown out of focusing, and is easy to re-focus between filters, or refocus several times during a long exposure run as the world cools down. (actually, it ended up a smidge more than 2 inches) Lighter than the existing focuser. I don't have the skills to build a focuser using a. I think I got what I wanted and seems best solution for me. (actually, it ended up a smidge more than 2 inches). adapter set screws to slide into. 100A81BF-2145-44D5-BC76-66DBF43BAD58.jpeg. Whether you need a basic rack-and-pinion telescope focuser for your homemade telescope project or a premium Crayford-type model with dual-speed focusing as a performance upgrade, you have come to the right place. Building the mirror box is tricky, because the entire optical assembly (mirror cell, mirror box, trusses, secondary cage) must balance at the center of rotation of the arms. Connect the Arduino USB cable and upload some test sketches. 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. A 6 in primary mirror does not have enough weight to make the dob stable. (I didn't have the primary mirror yet). Finally, I glued a strip of Ebony Star laminante to the curves edge of each side bearing using contact cement, using a flush edge bit on a router to bring the edge of the laminate even with the edge of the wood after the cement had set. my 12.5" trackball, but I didn't The wide square footprint would make it pretty stable when mounted to Step 3The Side Bearings and Rocker Sides. I built a second set of electronics, and I had the NEMA 17 Direct Drive motor left over since it didn't work for my Orion ED80T-CF refractor. I tried this one first and found it wouldn't work for my application. Un-real!!! They have many items for ATMers and I had frequently visited their website when planning my scope. See the images how I plan to assemble it. Most of these have one or two set screws. The sides were attached with wood glue and clamps with a few small brads to hold everything in place. I marked the expected position of the secondary by measuring 61 inches down from the end of the tube. His passion is using CAD design and his homemade CNC router to bring large wood projects to life. I only do functional. But, like many of you I'm sure, the biggest reason I'm doing this is for the pure geeky fun of it! It's easy to shim it to exactly 2" with adhesive labels placed one at a time inside the tube until a 2" eyepiece or 1.25" adapter is snug. I have no idea how much mail this idea will generate, so I can't document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E")); Made of plywood, the rocker box supports the mirror box on 1 teflon pads, allowing it to rotate vertically. The Crayford Focuser and DIY Focuser for Homemade Telescope By trukmeeilee in Circuits Cameras 3,461 3 1 Download Favorite By trukmeeilee Follow More by the author: The Crayford focuser is a simplified focusing mechanism for amateur astronomical telescopes. really stiff and light for their size, and even though a #2 is pretty I don't *do* pretty. I used my router to "mill" a flat area for better contact with the focus adjustment rod. If you don't want to go that route, contact me at gary.hethcoat@gmail.com since I have a lot of spare parts and I can sell you a "kit" with a PCB and only the parts you need. This was to allow the circle cutting jig to be attached to the board to cut the arcs from a center point of 25 inches above the ground. This resulted in a gear that wasn't true and "wobbled" a bit. A bit of a monster! Share a cool tool or product with the community. Trim off any unused fabric along the base. I waited until dark and pointed the scope at the sky. It uses a primary mirror to capture and reflect light, a secondary mirror to direct light into an eyepiece, and a focuser to make fine adjustments for viewing. You need to order it sized for your focuser shaft size. Home centers and hardware stores did not carry large sizes. This consists of a small black box of electronics. Homemade astronomy. the side of a rigid secondary cage. . It may take you a while to adjust the image correctly, but it's not hard to do, just time consuming. If your optical train is heavy and the focuser has to bear it (see above) then this motor may be a better choice. Community Forum Software by IP.BoardLicensed to: Cloudy Nights. After cutting the circles for the side bearings, I set up the jig to cut the curved edges of the rocker sides. (Sorry you Let me see if I am able to collect all the parts needed. I have built a homemade electric focuser for my Celestron 8SE using a radio control hobby servo and some spare parts. Plus it comes in black, so you don't need to paint it (or worry about paint flaking off it). scope, I only put knobs on the outsides. Keeping with the 'simple ' part of your request, here is a helical 2"/1.25" focuser made from std plumbing parts. by cranking When you add the minimum distance from the eyepiece to the secondary mirror together with the distance from the secondary mirror to the primary, the total length should be the primary mirrors focal length. All in all it seemed like a pretty robust design, so I gave it I also doubled the thickness of the rocker sides (not the front wall) to provide better support for the heavier tube. The drawings are only approximately to scale. The pieces were cut down to 15 3/8 and 14 3/8, allowing just under 1/8 inch on each side. 7 years ago 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. I first tried my 32mm plossl eyepiece. A week after they said they would send the secondary and other parts, I called to ask if things had been sent. The focuser knob had two set screws. I attached them with very small brads, countersinking the brads. Nice work and great instructable! focuser. After looking at many focuser options with a big range of prices, I decided to order a GSO 2 speed Crayford focuser from ScopeStuff. I did run into a small problem with the focuser. It has a 6mm shaft. After waiting for the stain to dry for a day, I applied polyurethane in two coats, going over the surface with 0000 steel wool between coats. I did not wrap the tube until I had completed the base. I installed the spider first, about one inch down from the end of the square end of the tube. that is a great website that guy has some fantastic photos. Position "0" is with the focuser all the way IN (at least for a refractor). 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. I had nearly completed the base and put things together for the first time. A Pocket Sundial From a Broken Pocket Watch! 4 years ago Get hands-on with kits, books, and more from the Maker Shed, Skill builder, project tutorials, and more. I found out pretty quickly that building my own telescope would only be a bargain if I made my own mirror and mechanical parts. Here is what I was working on but looks like I need a better design. I'll use an aluminum tube for the finished draw tube but for now the plastic tube .