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. Secondary mirror with spider holder Search on eBay for a matched set. This is my copy of the telescope that Sir Isaac Newton presented to the Royal Society of London in 1671, and is considered to be the first successful reflecting telescope. We all know the problems with focusing. A wide hole will let the knitting needle creep Using a compass, I drew lines for the inside and outside of the Ebony Star ring on the top and bottom of the rocker bottom. I'm also going to focus on only one version of Robert's focuser (there are many). However more than the focuser, I liked your scope. Thanks Pinbout for sharing your design. Thanks for your article. This allows for a small clearance between the outside of the tube and the inside of the tube box (14 3/8). I call shenanigans on every picture in this post except for the the moon. Use mild soap and distilled . The last chapter of the book describes a plan for an 8 inch sonotube dob with a few design elements from their truss design, and, as I read that chapter, the simplicity of its construction was very appealing. DIY Truss Dob input: How to design truss? Also, I will work with my computer geek buddies, so that we eventually automate it using Linux on a Rock64, to run kstars for tracking, on INDI. you could probably space the bearings 3/4" apart instead of 1" and mount 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. together tech enthusiasts, crafters, educators across the globe. Showcasing amazing maker projects of 2022. How to build a 12.5 inch closed tube Dobsonian telescope. I did run into a small problem with the focuser. 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. Crayford focusers are considered superior to entry-level rack and pinion focusers, normally found in this type of device. ASIAIR - Is there an easy way to load Messier catalog into Autorun? "https://ssl." Membership connects and supports the people and projects that shape our future and supports the learning
You need a drawtube of course. I had initially allowed for more of a gap, but realized once I cut the pieces and held the tube inside them that my gap was too large. This proved fatal for the stepper motor! After going over the surfaces with a tack cloth to pick up the saw dust, I applied the stain and went over it with cheese cloth rags for an even finish. I sourced my own Stepper motor and 1:150 reduction gearbox from RS, who are just up the road. You won't need to write any sketches from scratch, but you will at least need to figure out how to upload them to the Nano. Another vote for Pierre's helical Crayford design. love to hear from people who are interested in this focuser design. I 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. curated by us, the people behind Make: and the Maker Faire. Fast forward a few months to the next time I had the tube outside. So I decided to make my own, using my normal "blunder in naively and see what happens" approach to making things. I did not wrap the tube until I had completed the base. Dobsonian telescopes are popular with amateur telescope makers for their ease of design and construction, portability, and their use of large optical mirrors. The curved sides of the Side Bearings are also covered with strips of Ebony Star that glide on the teflon pads on the curved edges of the Rocker Sides (figure 3). It would cost less and they have a very good reputation. Position "0" is with the focuser all the way IN (at least for a refractor). After researching several possible sources for a primary mirror, I decided to order an f/5 12.5 inch mirror from Discovery Optics. It's the same in form, but has a perfect, true 13.35mm hole. The part is very strong! Please re-enable javascript to access full functionality. The lumber yard also gave me a lower price than I expected. The hole did need to be enlarged slightly by moving the bit within the hole , but in the end, the fit seems right. I have not yet figured out a better way to hold the tube. When I looked at the costs, I seriously considered buying an Orion telescope instead of building my own. Sew the seam, and sew an elastic cord into the top to secure it to the secondary cage. On the bottom of the Bottom board is a ring of Ebony Star laminate that glides over the three teflon pads located directly above the feet on the ground board. The day I received the refund, I ordered a mirror cell from University Optics. A Pocket Sundial From a Broken Pocket Watch! All Orion 1.25" and 2" telescope focusers are engineered to provide smooth drawtube action to ensure you hit the exact focus point . In the "ARDUINO FIRMWARE" folder, in it you will find a ZIP file "myFP2-Firmware 312-1.zip". My concern turned to alarm when my wife told me that Discovery had charged the balance due on all items to my account a few weeks earlier. See captioned photos 22-25 here:https://www.cloudyniractor-focuser/ for more detail on building a flush valve focuser, as Bob mentions. I got no response to phone calls or emails after another week, and decided to wait until the primary would be finished in another two weeks. 5 weeks after I had ordered the mirror, I called to ask about its status. It seems to My homemade motorized telescope focuser for Celestron C8. var gaJsHost = (("https:" == document.location.protocol) ? A Pocket Sundial From a Broken Pocket Watch! I will post the pic of final focuser once ready. 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. Or rather, I hated it. My other telescope is a Celestron NexStar C6E. The silly colours are mainly due to me experimenting with various clothes dyes in the anodising. This focuser (see pic at bottom) was motorised by me several years ago, but the motorised system didn't give me very fine control, and the motor running at fast speed tended to make the Artemis camera crash. The focuser 'knob' on the Celestron is just a rubber sleeve that usually pulls off easily. In scaling up the K/B 8 inch design, I made a few changes that, I hope, will improve the design for 12.5 inch aperture. I tried to call, but the voice mail had a recording stating that the customer was unable to receive messages. "); Because mirror flexure can distort an image, supporting the mirror properly involves building a flotation cell. Next, attach the eyepiece and the focuser to the top part of the telescope tube. I called to express my concern and was told that it had all been packaged a few weeks ago and that it, For complete instructions on building a telescope such as this one, I strongly recommend buying a copy of, After cutting the circles for the side bearings, I set up the jig to cut the curved edges of the rocker sides. drneilmb, thanks for sharing the focuser design. on Introduction. Yet I was also becoming infected with aperture fever. too far. It has become an indispensable piece of equipment for me that so beats hacking and filing PVC pipes etc. The Focuser and other items: (Scope Stuff). on Step 3. 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 I also wanted to buy the other mechanical partsmirror cell, spider, secondary holder, and focuserso that the performance of these pieces was not limited by my skills. There are some test sketches in the "Tests" folder, start with those. Picture of DS-4. I attached keepers 1 inches wide by 5 inches long, extending above the bottom of the arcs by about 1 inches. 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. you don't need to paint it (or worry about paint flaking off it). on Step 5. This is the kind of simple off the shelf design I was looking for. Now I can simply insert the PVC cap on the end of a 4" pvc tube. When you want to focus, you just open the program and press focus. Before finishing the tube with a wrap of veneer, I wanted to make sure that the primary was in the correct position. I wanted the long focal length for good contrast. I plan to use an FTA over it in case an extension is needed. Perfect for visual observations with very heavy mirrors. If you enter it in the next contest please let me know and i will make sure to vote for you. 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 . 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. Quick demo of my motorized focuser, and I will create a detailed tutorial if enough people are interested. Able to shift heavy loads of kit ie over 1000g. 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. The Artemis module works extremely well, and is to be strongly recommended. The length of the Rocker Front also had to be changed so that the outside edge of the Side Bearings matched the outside edge of the Rocker Sides precisely. Realizing that it could not be the University Optics cell already, I thought, Noit couldn't be but, in fact, it was. I started by trying to drill out a metal gear for the focuser shaft. For my project I needed a 14 inch diameter, and I had a tough time finding one. 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 on Introduction. I'm' glad I did, because I didn't like the first color that I had chosen. 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. Read the documentation though, there are a lot of functions and options. It is size 1.25 inch with a clear inside dia-meter. Cost is $25 - $30, and you will have 5 PCBs in about a week. I centered the focuser 8 inches from the top of the tube, using a 2.5 inch hole drilling saw with smaller holes for the bolts that would hold the focuser. This can be shimmed out with paper wrapped around the The secondary holder is adjustable, so I could didn't have to get the location perfect. I didn't receive any confirmation email after a few days, so I tried to send them an email. One 6in dob I made was a complete failure. This sure is going to be a project I will work on. scope, I only put knobs on the outsides. Once built, line the undersides of the arms with textured ABS plastic as a bearing surface. To hold the tube in place within the tube box, I used a combination of pieces of felt inside the box and wooden shims between the tube and the box. The drawings are only approximately to scale. Slewing to find an object and then tracking an object on the sky, so when you make a homemade telescope on the motorisation process you will need high speed for slewing and low speed for tracking or fine movements. I told them to take their time and get it right. So, am curious to see what others have designed and built and proud to show off here on the homage to Crayford thread. I marked the expected position of the secondary by measuring 61 inches down from the end of the tube. Focuser (GSO 2 speed low profile Crayford): $139 Ebony star strips: 2 @ $10 Ebony star ring: $59 Teflon strip: $11 Telrad base: $10 Baltic Birch " sheet (60X60): $42 Baltic Birch 5/8" sheet (60X60): $48 Circle cutting jig: $30 Birch Veneer (4X8 piece): $65 Hardware, stain, other supplies: $80 Total cost for supplies for this project: $1700 The flat wants to be running parallel to the long axis of the tube. It features 2 semicircular arms, and mounting points for the trusses (T-nuts are fine), as well as a lid to keep the mirror safe when the telescope is not in use. 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. Share it with us! Thanks again for the 'ible. wobbly knob still works, and adds character. experimented with various wires and rods and eventually decided that a Now attach the screw eyes and the rubber band on the side of the board. Dobsonians come in all shapes and sizes, from small 4-8 builds all the way up to massive 24-36 creations. It turned out that they had an incorrect zip code and the package was still waiting to be sent. Someone is pulling someone's leg here. Brandon Lawler is a hobbyist telescope Maker and an active member of the Central Texas Astronomical Society. Just to make sure I liked the stain, I applied some to a piece of scrap wood. I took the whole tube assembly outside. Before you do this, the stepper motor will probably move, but it will make a 'stuttering' sound instead of moving smoothly. The rocker arms must also have guides to keep it on the track; flat metal 12 braces lined with ABS plastic work nicely. on Step 5, 9 years ago Plus it comes in black, so you don't need to paint it (or worry about paint flaking off it). Thicker knitting needles would be even 4 years ago I started with a spacer that with a inch outer diameter. Thank you for your pages. Get hands-on with kits, books, and more from the Maker Shed, Skill builder, project tutorials, and more. The telescopes size is classified by the size of its mirror. larger diameter. It turns out that sonotubes are a stock item in 8 inch, 10 inch, 12 inch, and sometimes even 16 inch diameters. I also wanted to strengthen and protect the cardboard tube. I will have a lot of fun building my homemade 12.5 inch Dobsonian Telescope!!! This is the first telescope that I have built. The focuser knob had two set screws. Here is a link to the main FILES area on Robert Brown's site. 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. Your choice here will be recorded for all Make.co Websites. An Altitude Azimuth mount would also require a field rotator.There's no way these were taken with an Orion GoTo Mount. LVLaserTech is right please do not vote for the pictures my instructable is for the build of the telescope not the quality of the photos.and as i said before i was not there is there a possibility that he sent me the wrong photos sure is there a possibility that he used a different mount than the one i saw sure is there a possibility that he is lying to me me about what he did sure. This motor has a larger shaft diameter (8mm) and is quite a bit heavier overall than the direct drive motor, mainly because of the gearbox. This is not recommended for shared computers. Among amateur telescopes, the most common are focusers with landing diameters of 1.25 ", 2", rarely 0.965 ", and even less often - 3". Very simple and portable. I had to take apart the focuser in order to get my bolts in place. rod for the drive axle it would have a fairly fine motion. once. Save over 40% off the annual cover price for a full year (4 issues) of Make. I laughed, packed up the cell with a long letter describing the series of events that led to the return, and put it in the mail. Bore out some 2.5 inch bar and mill a flat down the side making sure it is lined up. When you're ready to go on to testing with the windows driver, you want "myFP2_DRV8825_312-1", open that folder. And bolt to scope Instead of the rack and pinion, they have a smooth spring-loaded shaft which holds the focus tube against four opposing bearing surfaces, and controls its movement. 1N5408 3A Diode (you may need to make the pins smaller to fit through the holes in the board. Share it with us! Gift the gift of Make: Magazine this holiday season! . When they arrived, they were beautifully and carefully packaged with the secondary already installed in its holder. New Creation Tamil 6.96K subscribers Welcome to New Creation Tamil Our Channel include of Guiding Videos: 1.DIY Projects 2.Awesome Ideas 3.Tips You are inter with New Creation Tamil you can enjoy. Because thebasic movement and optics requirements are relatively simple, much of the design is left to the builder. The overall project is super cheap, we're building this thing for something like $50 in materials. You should now be able to drill the 4 holes at each corner. 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. 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. NEMA-17 Stepper Motor - see below, there are two options. The original Crayford Focuser is on display there. - Bill. Deep space photos like these require HOURS of exposure for each one. I suspected that the company was either in trouble or no longer in business. Make sure the shroud can slip on and off of the assembled scope, and that it stretches along the circumference (not lengthwise). This combination has the best resolution (steps/revolution), so I didn't see any reason to build anything else. 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! Able to make myself using my own humble tools (or toys as the pros will call them!) 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. I was finishing this inner debate when I got a copy of the book The Dobsonian Telescope by Kriege and Berry as a Christmas gift. Featured in the February, 2015 issue of Sky & (actually, it ended up a smidge more than 2 inches) Lighter than the existing focuser. The mount and tripod are pretty much useless for astrophotography. Funny how the bigger they are the better for dobs. I ground and figured the mirror with little troubles, making my focault tester, etc. The project took several months off and on to complete, although a skilled Maker could put a similar one together in a few weeks. 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. the bearings right at the edge of the frame, reducing the frame to I read the entire thread and surely its going to help me building my focuser. The heaviest piece is 40 lbs, and the total scope weighs about 60 lbs (not counting the baffle). So, for my telescope I used a 6mm to 5mm coupler available on Amazon. A week after they said they would send the secondary and other parts, I called to ask if things had been sent. My plan for wrapping the tube seemed good, but I am not too pleased with the final result. knitting needle where it goes through the hole, so it's not a big deal, surfaces to put the bearings in and a vee at the bottom that would hold I wanted to finish that instructable before the contest ended but was too late :-). If you mess up, you can turn the hole into a slot, but avoid Using a compass I drew circles on the top and bottom of the ground board to mark the inside and outside of the teflon ring on the bottom of the rocker bottom. ScopeStuff is awesome!! That's pretty much the focuser. It took yet another call a week later for the items to actually be mailed. In my build, the cage was cut on a CNC router from plywood, with threaded T-nuts added to support a truss assembly. I began building it in the spring of 2008, but the bulk of the work was done in July of 2008 with first light occurring on July 25. 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.