Doc Posted October 8, 2017 Share Posted October 8, 2017 As I now have a workshop with a Myford lathe and a milling machine I have decided to make an ALT/AZ mount capable of taking my 5" triplet refractor. I drew up quite a few plans and decided on a mount similar to the disc mount idea. It's basically a 6" cube with an opening back panel that will allow access to the azimuth and altitude shafts so they can be tighten to allow the correct friction to be maintained via the 5" discs of PTFE. The next step will be to bore the holes in the side for the bronze bushes. Until next time...... Link to comment Share on other sites More sharing options...
Stu Posted October 8, 2017 Share Posted October 8, 2017 Looking good! Always thought it possible to make something better than those on the market so I'm looking forward to seeing your progress. Link to comment Share on other sites More sharing options...
Doc Posted October 8, 2017 Author Share Posted October 8, 2017 Thanks Stu, it's made out of 1" thick aluminium so pretty strong. I have owned many mounts over my time so have quite a lot of experience in comparing different models. Link to comment Share on other sites More sharing options...
happy-kat Posted October 8, 2017 Share Posted October 8, 2017 Loving the visual aesthetics of the cube. Link to comment Share on other sites More sharing options...
Stu Posted October 8, 2017 Share Posted October 8, 2017 25 minutes ago, Doc said: Thanks Stu, it's made out of 1" thick aluminium so pretty strong. I have owned many mounts over my time so have quite a lot of experience in comparing different models. I think if you can get the smooth functioning right depending upon the side to side balance, and also the ability to fine tune the tension you are most of the way there. 5" PTFE discs should sort the tension part anyway Link to comment Share on other sites More sharing options...
John Posted October 8, 2017 Share Posted October 8, 2017 I'm looking forward to following your progress on this - I love alt-az mountings and have considered many options for my 130mm F/9.2 triplet frac. Currently a Skytee II does the job but I'm always interested in other solutions Link to comment Share on other sites More sharing options...
Doc Posted October 8, 2017 Author Share Posted October 8, 2017 I was one of the very first owners off the Losmandy AZ8 John, when it first made an appearance and it's a great mount but I've always wanted to build my own so am going to give it a go, hopefully I can get it to work and be a great mount. If it works I'll fit encoders to it as well. Link to comment Share on other sites More sharing options...
Doc Posted October 9, 2017 Author Share Posted October 9, 2017 A few more photo's... The altitude disc was turned on the lathe. The finished size was 5.250" x 1" thick. The plastic disc is made from 6mm UHMWPE which is supposed to be a plastic with a very low coefficient of friction so I gather should work on this mount. The other disc was turned on the lathe and then with the M10 bar inserted the plastic was sandwiched between the tow and all trimmed to size. A 10mm hole was drilled into the centre of the cube and the disc secured to the cube. At a later date the 10mm diameter threaded bar will be replaced with a 1" stainless steel shaft and bronze bush. Close up view of discs and friction plates. Showing the bush that will be fitted once the cube has been bored. All connected up. That's it for now...... Link to comment Share on other sites More sharing options...
Stu Posted October 9, 2017 Share Posted October 9, 2017 Looking very nice Doc! I envy your metalwork skills! Link to comment Share on other sites More sharing options...
Doc Posted October 9, 2017 Author Share Posted October 9, 2017 Thankyou Stu, this is the first time in 30 years since my apprenticeship as a turner that I have touched a lathe so pretty happy with it so far, it's like riding a bike, you never forget. Link to comment Share on other sites More sharing options...
John Posted October 9, 2017 Share Posted October 9, 2017 Very interesting Link to comment Share on other sites More sharing options...
Doc Posted October 10, 2017 Author Share Posted October 10, 2017 A little bit more work done. The bush is 1 1/2" x 1" x 1 3/4" in size and the hole was bored out in the milling machine as the parts are to big for the lathe. The bush was then pressed in using the vice. The shafts are only aluminium at the moment but once it's all working I'll remake in Stainless steel. I then made up some thumbscrews for the back panel. I undercut the threaded shaft so the thumbscrews will not be lost. That's the Altitude axis done, the next job is the Azimuth axis. Until next time. Link to comment Share on other sites More sharing options...
Doc Posted October 11, 2017 Author Share Posted October 11, 2017 Forgot to take photo's of the process but did manage a few at the end. Both axis have been done now. Feeling very smoooth and cannot feel any play at all. View from the back. All I need to do is remove panel via thumbscrews and adjust with a 19mm spanner. I'm going to make or buy a thin 19mm spanner and stick inside with magnets. View from the front. Next is the riser, I think I'm going to need at least 10" to make refractor viewing comfortable. There are a few scratches and marks on it that will need rubbing and polishing out. Unsure of what finish to have on it, either polish to shine, paint, powdercoat, anodised, or plastic dip. Until next time..... Link to comment Share on other sites More sharing options...
Stu Posted October 11, 2017 Share Posted October 11, 2017 Beautifully simple doc. Do you think you will need a counterweight at all? Link to comment Share on other sites More sharing options...
Doc Posted October 11, 2017 Author Share Posted October 11, 2017 I don't think so Stu, but I will know more once I've set it all up with the scope. The Esprit 120ED is a heavy scope so we will see. Link to comment Share on other sites More sharing options...
Stu Posted October 11, 2017 Share Posted October 11, 2017 Just now, Doc said: I don't think so Stu, but I will know more once I've set it all up with the scope. The Esprit 120ED is a heavy scope so we will see. Should be good, look forward to seeing the results Link to comment Share on other sites More sharing options...
Doc Posted October 12, 2017 Author Share Posted October 12, 2017 A few more photo's.... Made a 10" riser for the mount. I had so many plans in my head but settled on this one. It's really strong and there is no flex in it at all. I already have a few saddles so will adapt one of them and then mount the scope. That's it for now. Link to comment Share on other sites More sharing options...
Doc Posted October 13, 2017 Author Share Posted October 13, 2017 Well here it is.... No need for counterweights, lovely and smooth, stays put while swapping from large to small eyepieces, and good to look at. Takes the weight of the Espirit so easy, I would imagine an 6" triplet would be a breeze. Just need to sort out encoders and paint job. Also going to get a Berlebach Planet tripod for it. Link to comment Share on other sites More sharing options...
John Posted October 13, 2017 Share Posted October 13, 2017 Lovely job !!! Can you make another one ? Link to comment Share on other sites More sharing options...
Starlight 1 Posted October 13, 2017 Share Posted October 13, 2017 Looking at post all week, so time say nice looking mount love the rat cage look. Link to comment Share on other sites More sharing options...
Doc Posted October 13, 2017 Author Share Posted October 13, 2017 Thanks guys. To answer a few questions I would say the mount has taken me about month to make, and has cost me in materials about £300. I have just condensed it into a week of photo's. Link to comment Share on other sites More sharing options...
Stu Posted October 13, 2017 Share Posted October 13, 2017 Brilliant! A job well done I would say. How much does it weight, just out of interest? Link to comment Share on other sites More sharing options...
Doc Posted October 13, 2017 Author Share Posted October 13, 2017 Not sure Stu I'll weigh it over the weekend. Link to comment Share on other sites More sharing options...
happy-kat Posted October 15, 2017 Share Posted October 15, 2017 Looks very impressive. Link to comment Share on other sites More sharing options...
Doc Posted October 15, 2017 Author Share Posted October 15, 2017 On 13/10/2017 at 20:18, Stu said: Brilliant! A job well done I would say. How much does it weight, just out of interest? Just weighed it and it is 13.9 Kg or 30.6 Ib or 2.2 stone Link to comment Share on other sites More sharing options...
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