(I didn't have the primary mirror yet). 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. Until I see photos of this scope setup for these pictures and an explanation of the exact equipment used, I cannot believe that these pictures were taken with this OTA. 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. The version number "312" here may change if Robert posts new firmware. If you're not familiar with Arduino, watch some tutorial videos. Your design is simple and nice. Some quick tips to note if you are making a homemade telescope are: 1. I would also like to know about how you can take such fantastic pictures without a field rotator and an autoguider system. I have no dog in this hunt whatsoever, but if people are impressed by these photographs and vote for it because of them when there's no proof that this scope generated the photos and there IS data to the contrary (see below), then that's certainly not fair to the other contestants. My first telescope I built was a 10" F8. I did run into a small problem with the focuser. Nice looking telescope. Given that you can make the drawtube any length you "https://ssl." For my project I needed a 14 inch diameter, and I had a tough time finding one. 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. Using heavy grit sandpaper I brought back the surface of the keeper enough for the side bearings to fit inside the felt pads. The mirror box encloses the mirror cell and allows the entire telescope to rotate vertically. haven't yet found any design elements that need improvement. The secondary holder is adjustable, so I could didn't have to get the location perfect. I attached small felt pads to the inside of the keepers to protect the side bearings from scratches, but discovered that the side bearings would not fit because of the thickness of the pads. After the second call, I received a response that it would be ready at the end of the following week. I then temporarily installed the secondary mirror so that I could measure the approximate distance to the center of the secondary in order to locate the holes for the focuser. I have one on my 12" f/5 truss dob and the focuser knob is on the top surface of the UTA. I would love to see your build when you are finished with it . I attached them with very small brads, countersinking the brads. It has become an indispensable piece of equipment for me that so beats hacking and filing PVC pipes etc. 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. Perfect for visual observations with very heavy mirrors. Orion Telescope Focusers | Buy Direct and Save! 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. I wanted a tight / press fit, so I only added half that, 0.25mm. Other supplies that I bought for this project include wood, various bits of hardware, stain and finishing supplies, and a circle cutting jig for a router. The focuser knob had two set screws. on Step 3. Able to make myself using my own humble tools (or toys as the pros will call them!) Like i said these are not my photos and i cannot coment on exactly how he set it up as i was not there all i can say is i saw the mount he used when he picked up the telescope. I am working on a diy focuser design for my 6" F/8 telescope and asking suggestions for simple focuser. I decided that my best option was to scale up their 8 inch design for a 12.5 inch scope and sacrifice the portability and easier storage of a truss scope for something that I felt confident in building myself. Contact cement is permanent, so the only solution would be to replace the tube! Stellafane The Focuser Before I wrapped the tube (and before I discovered the problem with the primary placement) I determined the balance point on the tube. Before finishing the tube with a wrap of veneer, I wanted to make sure that the primary was in the correct position. 11 years ago It seems to The Focuser and other items: (Scope Stuff). 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 It may take you a while to adjust the image correctly, but it's not hard to do, just time consuming. This arrangement turns 100% true, no wobble. Move the jigs until you can comfortably place a variety of eyepieces in the focuser and get a sharp image, then carefully measure the separation distances. We moved the operation to a nearby park and got a focused image of the most distant trees (300-400 yards away) quite easily. 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. The rocker arms must also have guides to keep it on the track; flat metal 12 braces lined with ABS plastic work nicely. The blue pieces of the rocker box and ground board are arranged as in the diagrams in (figure 2). surfaces to put the bearings in and a vee at the bottom that would hold 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. Total cost for supplies for this project: It took a lot longer than I expected to receive my mirror and other parts from Discovery. I had nearly completed the base and put things together for the first time. Obviously an open truss telescope. Fairly easy to build and could be adapted to suit any SCT focuser. Thanks for the great comment. Upload that main sketch to the Nano. The Crayford focuser is a simplified focusing mechanism for amateur astronomical telescopes. Our websites use cookies to improve your browsing experience. like, you can have as much focuser travel as you want no matter how 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. Because mirror flexure can distort an image, supporting the mirror properly involves building a flotation cell. Let me see if I can get similar plumbing parts here. On that noteWARNING:do not look directly into the sun and never point a telescope into the sun without proper filtration you can damage your telescope and burn your retinas and possibly go blind i am not a astrophotographer so i cant comment on the quality of the pictures since there is so much doubt on the photos i will gladly take them down. The focal length of the mirror is 61 inches. adapter set screws to slide into. I'm only hoping to supplement it a bit with some info and pictures aimed at those with limited skills (such as myself) :-) I'm not an electrical engineer, I'm more of a software guy with some limited knowledge of electronics and basic soldering and assembly skills. until a 2" eyepiece or 1.25" adapter is snug. All in all it seemed like a pretty robust design, so I gave it The sides were attached with wood glue and clamps with a few small brads to hold everything in place. Download and unzip. Thicker knitting needles would be even The bearings only need to be weight. See the images how I plan to assemble it. the drive shaft close against the drawtube. Tom's Homemade Telescope Page - DIY Craford Focuser - Google The cost is a bit more than some of the other combinations, but by only $10 or $20. I feel it is a wonderful thing to free oneself from the "store-bought" world, as Tombaugh did, and to use your imagination and skills to develop your own, personal way of viewing the sky. (Technically, it should have been 62.5 for a 12.5 inch f/5, but when the mirror came it had a note on the back that the focal length was 61 inches.) flexing. installations. The box should be deep enough to allow the mirror box to swing all the way down. Share a cool tool or product with the community. I carefully cut exactly through the center of each side bearing circle to make my semicircles. 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. document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E")); eyepiece on the ground (or worse, on your primary mirror!) I I gave them a call and they said they had one on the shelf14 inches in diameter and 12 feet long! Dozens of projects in every issue covering electronics, craft, fabrication, and more, Learn tips and skill-building tutorials from experts in the maker community. Pioneered by John Dobson in the 1960s, the instrument combines a Newtonian reflector telescope with a unique two-axis movable base. Sh2-169 and Sh2-168, IC5146 Cocoon Nebula, Caldwell 19, Sh 2-125. I bought a 4" PVC Sewer pipe cap, used a hole saw to cut a 2.25" hole then attached the helical thing to the PVC cap. Read the documentation though, there are a lot of functions and options. This simple homemade device will reduce star trails far better than if the camera was mounted on a tripod alone. I really had to, since the underside of my telescope's focuser is all curves, no flat area for attaching the mounting bracket. The 48 inch width of the veneer was close enough to the diameter of the tube that I used it as is. I pointed it at distant trees and had no problem bringing the image into focus with all of my eyepieces. If you enter it in the next contest please let me know and i will make sure to vote for you. 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. To view, go here: http://emediadesigns.com/focuser/ Robert is a super guy and more than willing to help those who choose to follow in his footsteps. 100A81BF-2145-44D5-BC76-66DBF43BAD58.jpeg. This can be shimmed out with paper wrapped around the It has a 6mm shaft. (actually, it ended up a smidge more than 2 inches) Lighter than the existing focuser. Someone is pulling someone's leg here. I used my router to "mill" a flat area for better contact with the focus adjustment rod. Depending on your telescope, one of the Brackets that Robert has may work for you. Staples or finishing nails work fine, but be sure they dont bump up above the surface of the plastic. Because thebasic movement and optics requirements are relatively simple, much of the design is left to the builder. This sure is going to be a project I will work on. I'm also going to focus on only one version of Robert's focuser (there are many). Headers for the LEDs, buzzer (2-pin) and temperature probe (3-pin). This allowed me to cut perfect identical circles. The back of the mirror floats on 3 or more support points (this build uses 6) that are calculated usinga software tool called PLOP. larger diameter. You will need to order one sized for your telescope's focuser shaft size. A smart collection of books, magazines, electronics kits, robots, microcontrollers, tools, supplies, and more
The dimensions of the Tube Box Sides are based on the outer diameter of my tube14 3/16. Similar photos at http://www.telescopegeek.com/gallery.htm require 100+ minute exposure times on his 20" telescope and $3200 camera. a try. This unit takes signals from your computer and drives the stepper motor on the focuser. 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. I like the old way of using stepper motors and other stuff introduced years ago by Mel Bartels, he is a master for me. Earthbound1 likes this #2 dave brock Mercury-Atlas I have not yet figured out a better way to hold the tube. The wide square footprint would make it pretty stable when mounted to Tips If you've got a 1.25 inch focuser, You can also use it for an objective. The cage should be a hollow cylinder about wider than the mirror, with the focuser mounted directly facing the secondary mirror. the tube is cardboard as well, you can also get a quality mirror at telescope.com for much cheaper. This allows for a small clearance between the outside of the tube and the inside of the tube box (14 3/8). Given any mirror measurements, PLOP will provide the ideal support layout and how much distortion to expect for any number of flotation points. I'm' glad I did, because I didn't like the first color that I had chosen. Building Your Second Homemade Telescope - Part 1 - HubPages Save over 40% off the annual cover price for a full year (4 issues) of Make. I did find, though, that the 3D printed gear would slip on the shaft, so it needed a set screw. 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. I am thankful to enjoy the inspiration, and the details, that you provide, as I will soon be constructing a Dobsonian Telescope. 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). After another 3 weeks, I was concerned that I had not received the mirror. That helps with low-profile Sew the seam, and sew an elastic cord into the top to secure it to the secondary cage. I had talked with their owner about mirrors and mirror cells once, and I was very impressed by his knowledge of telescope building. 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. I also decided to make a separate mounting plate for the stepper motor, since I figured aligning the shafts precisely would be all but impossible. A week after they said they would send the secondary and other parts, I called to ask if things had been sent. ill ask him for a detailed list of what he used and when i get that ill post it here for you. This motor is available on Amazon. Once Id built a CNC router, I embarked on my third telescope, featuring a 16 primary mirror with aluminum trusses, wide vertical bearing arcs, a steel front-adjustable mirror cell, and a rotating base. Robert Brown did an excellent video on how to work out your stepper motor requirements. try { The kit just contains the electronics - it is up to the user to find a stepper motor and attach it to their own telescope focuser. Put it all together A Pocket Sundial From a Broken Pocket Watch! stronger, but would give me a coarser focus action because of their you don't need to paint it (or worry about paint flaking off it). 11 years ago During assembly, youll attach the trusses to the mirror box, then sit the secondary cage on top and bolt everything in place. 1N5408 3A Diode (you may need to make the pins smaller to fit through the holes in the board. An electronic focuser, which moves the focus knob through a combination of hardware and software, solves this problem. The belt and pulleys are off-the-shelf items available on Amazon. an inch or so apart, so the focuser body could be pretty low profile. 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.) Several clamps were used to hold the pieces together overnight. forces the knitting needle against the drawtube and the drawtube against I also doubled the thickness of the rocker sides (not the front wall) to provide better support for the heavier tube. The base of the telescope should be a wide, sturdy square or circle of wood with teflon bearing pads matched to the ABS plastic ring of the rocker box. It turns out the the extra 1/16 allowed far too much side to side movement between the rocker and ground board. It's the same in form, but has a perfect, true 13.35mm hole. If you connect the 12V power with the barrel connector (right side of photo), the Nano should light up without the USB connection. Im quite happy with the result, and the view in its large mirror is phenomenal. Trim off any unused fabric along the base. 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. off the bearings. Then it was time to stain and finish. Or rather, I hated it. an eyepiece. think that design would be rigid enough under the weight of a diagonal Cost is $25 - $30, and you will have 5 PCBs in about a week. You reach a point where the picture doesn't seem to change much, so you never know where the very sweetest spot in the focus is. (A badly tilted focuser may subtly alter the illumination pattern of the focal plane to a degree that would be impossible to perceive visually but that's about it.) Please explain, in detail, how you attached your tube to the very unique drive system of an XT12G mount. wobbly knob still works, and adds character. Very simple and portable. 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. These will be stored in your browser only with your consent and you have the option to opt-out. initiatives for the next generation of makers. Since my plan called for purchasing the mirrors and mechanical parts there were several decisions to be made and several vendors to contact. Inside the OTA is a ring of tightly fitting flocking paper that prevents any light getting in around the drawtube. That's pretty much the focuser. I will get good 30-40 mm focusing range. It is not very powerful, it will not supply enough torque if you put any load on it or have a heavy optical train (like I do) and the focuser has to "pull" it upward when the telescope is vertical. I knew that I would be returning the mirror cell to them, but just for fun I decided to see how it would fit in the tube. They said they would make the brackets extra long to accommodate the mirror and it would take about a week. (actually, it ended up a smidge more than 2 inches). knob, and a drill press to make sure the hole for the knitting needle Over how many nights did this photography session take place? For about $3 we can buy a tank valve kit that has a threaded 2" i.d. When they arrived, they were beautifully and carefully packaged with the secondary already installed in its holder. I don't have the skills to build a focuser using a. My other telescope is a Celestron NexStar C6E. After cutting the circles for the side bearings, I set up the jig to cut the curved edges of the rocker sides. forward and back along with the drawtube when you focus, and you'll get 10 years ago If your optical train is heavy and the focuser has to bear it (see above) then this motor may be a better choice. As I understand, you are using it for a refractor. 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 interior diameter is just a nudge over 2". I described it two years ago in this thread:https://www.cloudyniuser/?p=8879835 . #2 knitting needle would be just about right. How to make a $30 DIY star tracker for astrophotography I also have an extended photographic build diary of this telescope posted on Imgur. Plan ahead by carefully weighing all components and approximating the center mass of the optical assembly. The pivot bolt consists of a 1 1/8 inch brass spacer with an 11/16 inch outer diameter, a 3/8 inch bolt 2 inches long, a stop nut, and two large washers. While I will freely admit that most astro-photography is WAY beyond me, you certainly do NOT need a $3200 camera to do so. you could probably space the bearings 3/4" apart instead of 1" and mount Page 1 of 2 - DIY focuser design - posted in ATM, Optics and DIY Forum: Hi I am working on a diy focuser design for my 6 F/8 telescope and asking suggestions for simple focuser. with a genuine question or comment about the design. I am using scrap upvc pipe material. 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. When you're ready to go on to testing with the windows driver, you want "myFP2_DRV8825_312-1", open that folder. 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. Thanks for your article. The 2-1.25" adapter is a sink drain slip fitting in 1-1/4" size that slips into the large tube for 1.25 EP's. Orion Dynamo Mini for powering a Nexstar 6SE? With an outer diameter of 14 3/16, I cut the Tube Box sides 15 5/8 and 14 5/8slightly less than my extra inch extra on each side. Picture of DS-4. I then ran a bead of glue on the mark, and after it dried I cut out the nylon up to the glue. If you mess up, you can turn the hole into a slot, but avoid This scope was originally made as a travel scope using an eight inch mirror that I ground and polished at the St Pete Astronomy Clubs Mirror Lab. Sonotube (14 inch diameter, 12 feet long): $70, Focuser (GSO 2 speed low profile Crayford): $139, Total cost for supplies for this project: $1700. Look down through the empty focuser. Here we see the following components installed: Notice we are NOT populating the parts of the board intended for Wifi or BLED. A Beginner's Guide to Collimation - Gary Seronik I told them I was on my way. This combination has the best resolution (steps/revolution), so I didn't see any reason to build anything else. 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. 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. After another 3 weeks, I was concerned that I had not received the mirror. homemade Crayford focuser. CNC files (optional) Download the Sketchup files. I had considered using a clear finish alone, but decided to use a dark red finish on the base and a clear finish on the tube, just because I like the look. They're fairly I built mine entirely from CNC-cut plywood, and fastened it together with 2 bolts. The project took several months off and on to complete, although a skilled Maker could put a similar one together in a few weeks. The heaviest piece is 40 lbs, and the total scope weighs about 60 lbs (not counting the baffle). I used one of the top scraps from the rocker sides to mark an angle of 70 degrees from the center of the arc to the curved cut in order to properly space 1 X 7/8 teflon pads on the arcs. See above, this motor does not produce a lot of torque, but you don't need much for this application since there is no 'load' on the focusing shaft. To get this arc, I actually moved the radius of the jig in by 1/8 inch. More commercial crayford focusers are of a more enclosed form, whereas mine is more "open frame" approach. 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. Below are cutting diagrams and diagrams of the rocker and tube box with side bearings. 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. knitting needle where it goes through the hole, so it's not a big deal, 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. 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. It is used to setup water outlet from overhead water tanks. Use the externalMirror Edge Support Calculatorto decide whether to use a two-point, four-point (whiffletree), or sling support. I first tried my 32mm plossl eyepiece. You will need to order one sized for your telescope's focuser shaft size. guarantee a response, but I'll do my best to answer everyone who writes That is dirt cheap compared to the cost of commercially available focusers, which can top $1000 and are much heavier than what we will build. This will determine the size of the coupler you will use to connect the stepper motor. Im sorry to hear you couldn't make the contest. I sanded all parts of the telescope with 220 grit sandpaper followed by 400 grit, making a very smooth surface to apply the stain. This extra space would allow the tube to be repositioned within the tube box to rotate the eyepiece or balance the tube. I Hope to give you ideas if you are thinking about building one for yourself! Reply It turned out that they had an incorrect zip code and the package was still waiting to be sent. This might have been tempting if I wanted to build a 6 inch scopeat that size, they say that first-timers do pretty well at grinding and figuring their own optics. After the second call, I received a response that it would be ready at the end of the following week. that is a great website that guy has some fantastic photos. widening the hole. 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. How to build a 12.5 inch closed tube Dobsonian telescope. It's rigid, lightweight, and They use a simple plywood mirror cell, stating that for an 8 inch mirror this cell will be adequate. On the cutting diagram, you can see that the side bearings were cut 26 inches long.