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VaguelyAmused

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VaguelyAmused last won the day on November 11

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  1. CCD Freak, brilliant thanks for sharing. The picture of the big fork mount and scope, in what I assume was the workshop is warming, I think I spy a lathe in the far background Its funny, it was in the back of my mind, weight loading further out from the axis, when mounting the little ZS61 on top of the primary scope rather than side by side. Those fork mount photos make my "concern" somewhat farcical! Peter, almost as farcical, expecting technical support on a mount somewhat outside of any warranty period but could I ask, short of any full teardown, are there any "preventative maintenance" or recommendations such as oil/grease points I should be aware of? The mount is still smooth as butter and working brilliantly so I have no intention of touching it, which in itself probably already answers my question. Cheers Chris
  2. yuklop for a few pictures, maybe fit the AWR because the drive and mount are from a similar era and having some pictures like that would be brilliant. However, IMHO time has moved on a bit since the AWR. Its still a great system (I actually have an AWR intelligent handset, a grey version, along with two rather large Beacon Hill worm/wheels from an old mount - the guy had his observatory broken into and they took the microstep drive system unfortunately). Just with modern processors and stepper drivers there is a bit more "freedom", like switching between microsteps to get the best of both worlds, fine tracking and quick slews. No doubt preaching to the converted if you already have one fitted to your LX200 and have more experience than me with it! Have fun bringing the mount back to life and enjoy the decision making process behind what you put on it
  3. Thanks again for all the nice comments. I hope to get many years use out of it - though I did come outside after fireworks night to find a rocket buried in the ground like an arrow only 10ft from the dome... hopefully they would just bounce off if they did land on target but hopefully odds mean I never find out! Just finishing off odds and ends like a little arduino focus controller and arduino dew controller, but I've had moments of standing back now and it is starting to sink in what now exists in my back garden and the fun it should bring. skybadger, you are at risk of hearing the squeaky hinges of pandoras box open with those sorts of questions Initially, I was all set for polyester fibreglass over the plywood skin and then a final white flow coat. Truthfully, if I was to do it all again I think I would go straight for this choice. From all the copious, copious reading I did, I think polyester fibreglass would give the longest life, is the most UV stable and would need pretty minimal maintenance over the years. There were reports of it not bonding well to plywood : polyester fibreglass is great at bonding to itself, but not much else. However I think these comments are more in regards to "below the waterline" boat building, and not more "domestic" applications. I think the key is to wet out the plywood with slightly thinned polyester resin first, let that soak in then fibreglass over the top. However, as the build progressed, and the skin went on looking better than I thought it would, my mind started to lean towards keeping it as a bright finish and using something like yacht varnish. So this is the direction I started to go, which was silly. I made sure all plywood edges were sealed with thickened epoxy, and all joins were taped with fibreglass tape and epoxy. The problem with the tape, is on one edge of it where it is stitched, it has a ridge. I wanted a really smooth finish, so sanded the stitched ridge out. This lead me down a path to some "can it just end now please" decisions. What I should have done at this point, is carried on with the epoxy fibreglass encapsulation. I had the twill weave cloth and the epoxy ready to go, but by the time I'd finished sanding (there were at least 200 hours of sanding in this thing!) I was so utterly sick to death of it that I just couldn't face fibreglassing the whole thing and another round of sanding. So, the decision was still between a bright, varnished finish or paint. I did a few samples using yacht varnish, and two weeks later it could still be scratched off by a finger nail (even now, about 3 months on it can be). So I went with a paint solution instead. The first coat of white primer going on I was a bit heartbroken, I'd had my mind so set on a natural wood finish that painting just felt like defeat. However, now its done, I think it looks great and the white dome has a very traditional look to it. It also keeps the insides cooler than a darker wood finish wood, and should last longer than yacht varnish needing less maintainance. I came to the conclusion that the dome's primary purpose is to protect the stuff inside it, and white paint in the end was the best of the options I had left. With the paint, I am hoping maintenenace every so often shouldn't be too problematic, but I do wish I had just that extra bit of patience and will power to have done the epoxy encapsulation. Before this project I would have said "harsh weather" meant ice, rain that sort of thing, nope - the sun appears to be by far the harshest weather, pretty much any finish it seems is going to degrade over time, its then down to how easy the maintenance is. In regards the pad stones and sinking, that sounds like something "fun" to look out for over the coming months and years. I had heard of ground heave with frost, so have made them reasonably deep but definitely not house footing deep so I'll wait and see. Thanks for the heads up! All the best Chris
  4. markse68 thats really interesting about the papier-mâché, quite ingenious. Funnily enough when I had the main skeleton of the dome done, I did wonder about a similar approach to old planes, some sort of cotton skin stretched over and then doped in something like epoxy. I couldn't find anyone who had done anything close online as a reference, and had spent so much time getting to the point of completing the skeleton that I didn't want to tread completely new ground and have to wind it all back if it didn't work out. Security was a slight concern as well, I mean plywood isn't going to put up much of a fight, but probably more than cotton, even doped in epoxy. scotty1 thanks! Both yourself and Mr Spock have similarly keen eyes I really enjoy them, though bought long enough ago that they weren't quite as wallet draining as they look to be now. They are quite understated, most people would just pass them by, but put them on in the background and at some point guests usually stop talking and comment on them, once their subconcious catches up with what they are hearing I promised myself no more projects for a bit and to think about getting a pet kitten, but I look around my place and it really isn't inquisitive claw friendly!
  5. Hi Peter, Fantastic pictures, thank you for sharing and the history. The nostalga is too much and an honour to hear from one of the makers behind the mounts It reminds me slightly of the Blackbird Pilot reciting the story of the speed check radio comms. I now feel like the little cessna! EDIT: And thanks Stu, apologies I got excited about seeing the pictures from Peter I forgot to say thanks for the tagging
  6. F15Rules yeah its not until you place it next to something more standard that you realise its size. It is still all slightly sinking in a bit quite what I have. The observatory build was so long and had so many challenges that there were points I just wanted it to end. The mount I have been out of contact with for a while, my Dad and I spent many a night with it before I moved away to Uni and that was coming up to 20 years ago now. He is still very much around and well, but the dome he had built for it was on its last legs and the mount needed a new home (shh don't tell him about this thread, I don't know if he realises what he's given away yet! ) It was hard not to treat it like it was a museum piece at first, not for its age just the "don't touch in case you break it" sort of awe I had of it. The original drive failing, and having to swap out the motors and drive for an OnStep system probably did me a favour as it now feels a bit more "mine" and I am relaxed with using it. Of course the forecast is cloudy for a while now (sorry all!) but I can't wait to get out under more clear skies with it all.
  7. Thanks Paul, OnStep is an interesting project. It is (IMHO) slightly inaccessible just due to the number of different variants, generally centred around which board design you decide to use but well supported and there is forum support. There are, I believe, kits you can buy which come with the majority of the components including the PCB but you can go your own way too. I chose the "STM32 Blue Pill" variant as it was one of the best described and documented however for the price difference, I would probably recommend the MaxPCB version and a Teensy 3.6 at the moment, also because chip shortages mean getting an STM32 development board can be tricky. It is quite remarkable how feature rich it is, I am very impressed. It uses a mini wireless dev board to host a wireless server, acting either as its own access point, or connected to an existing wireless network. An ASCOM driver is then used to allow control from pretty much any program if you are so inclined. Alternatively, the Android application can be used to control it, including alignment, sync, goto's via an inbuilt catalog etc. Finally there is a handpad you can build (with a little OLED display!) that can do all the same as the android app and that can either be a wired or wireless handpad. I've had it connected to Stellarium for point and click Gotos (though will be moving away from Stellarium I think due to its crazy CPU usage on my little i5 NUC). PHD works very well with it and on the first night with a "that will do" polar alignment and no fine tuning I was getting +- 1 arcsecond accuracy, I honestly can't remember what I was getting with the Vixen GP but I don't remember it being as good, or as easy. I've attached a PHD graph (sort of, its N.I.N.As display of the PHD data, scale is in arcseconds). I think it will do better when I spend time properly polar aligning it. Cheers
  8. I suspect your investigations into the mount may have already led you to this, but for a bit more of the history associated with the mount (and the man) if you search on google for rob-millers-astro-promotions-pm1 there is a forum page with pictures and details of the Astro Promotions PM1 mount that is an interesting read.
  9. Hi All, With a risk of similar threads being started, I have an old mount that we (my Dad, mainly, and I) aquired many many years ago. At the time we retrofitted (in a way that could be removed) a Sitech Servo system - this was fairly bleeding edge at the time, and we worked to test/develop the Sitech Servo board and software with Dan Gray and Mel Bartels. This unfortunately failed recently and has been replaced by an OnStep system which is actually excellent. We have never really known the history to the mount. When we first got it, we saw similarities to it and the AP900/1200 range and a bit of reading started to paint a legend in the form of Rob Miller, who seems to have had his hand in a lot of the class leading mounts we drool over. Later, we found the Astro Promotions PM1 information/discussion forum and we are pretty sure it is indeed a Rob Miller design, and based on some recent posts perhaps also a collaboration with Peter Drew, both names I would be thrilled to have associated with this mounts design. A recent post by yuklop including the pictures of their mount, and they look almost identical. She is a real beast, with a 9" 180:1 brass RA wheel and a 6" 180:1 brass DEC wheel and came with 34KG of counterweights. Absolutely lovely, oozes quality and has been superb. It would be great to know a little more about it, it seems quite refined to be a prototype, but equally, its much much bigger than the PM1 so could have been a custom/commission back in the day? There may be more out there than I realise, and I hope Rob knows they are all still going strong and being loved. Kind thanks Chris PS: The Observatory Build is covered in a recent thread "Nerd Shed Observatory Introduction"
  10. This is beautiful! I have an incredibly similar mount (I will post it in a different thread to avoid hijacking your own), and it is so nice to see one of its brothers/sisters out there in the wilds and fantastic to get another bit of history about it, thanks Peter! We (my Dad and I) retrofitted a Sitech Servo drive years ago to ours, but with a recent failure on this it has been changed over to OnStep, you really won't be dissapointed. Its making me want to have a kid just so I have someone to hand mine down to, it feels like a family airlume. Enjoy the lovely find, and great it is being shown some love.
  11. Hi All, Sorry to revive a really old thread, but I wonder if anyone maybe archived the Catamount site before it went down? I have what is almost certainly a Rob Miller designed mount, and it sounds like the Catamount site had some really interesting history and pictures. A moment of painful nostalga when I clicked the link and found it was dead Its similar in design to the Astro Promotions PM1 but quite a bit bigger. Picture below and there are a few more on my recent "Nerd Shed Observatory Build" thread. Thanks all Chris
  12. Thank you all for the kind comments. Alan the "Wood Butcher" comment made me chuckle. I went into this having a reasonable amount of practical DIY knowledge (did up my house) but for the most part it was learning new skills. There was lots of try something, fail at it, come up with a different approach and try again. If I ever had to do it a second time around it would probably take half as long, but building a dome feels like doing it once in a life is enough Now its complete though I am really pleased - my Dad said a bit like climbing a mountain, remember to look back occassionally at how far you have come. I am down in Poole, Dorset if that is local enough for anyone that would like the other bits of the pole. They aren't completed piers though, just the rough cut bits of pipe that you would need to then fabricobble the rest together to turn it into a pier. Oh, what I did learn from the pier is my ability to estimate volume is awful. Its filled with kiln dried sand, after it was welded, through a 25mm ish feed hole in the pier top plate. I drilled a similar sized hole in a bucket, put that on top of the pier and then fed sand in through that. Quite theraputic watching the sand dissapear from the bucket. I'd bought 6 bags of sand thinking may need more. Half way through the 3rd bag the bucket stopped emptying! Now I have 3 spare bags of kiln dried sand to distribute around the garden perhaps in a Great Escape esque style. Regards Chris
  13. Hi All, I thought I would share my labour of love over the last few months... I say a few, ground was broken in April and I had my first proper night under clear skies with it on Sunday night, so maybe more than a few months! Apologies in advance it is hugely picture heavy, so I'll add a little summary now and let the pictures explain the rest. It is approximately 2.3M diameter and about 2.45M high. Built closely following the "How to build a home observatory" guide on the BBC Sky at Night website but with one or two tweaks and changes. I went back and forth between a roll off roof shed and a traditional observatory design and just liked the idea of the traditional look, but I wanted a little extra space to hide things away and help overcome a bit of the limitation of the circular shape, so added a little "nook". A 50W solar panel just keeps "critical systems" running when not hooked up to mains. It is a manual shutter. Again, angst over that for a while, but a mechanised shutter was going to need to be in two parts and potentially quite noisy for the neighbours when closing up at whatever time in the early hours. It also kept the build marginally simpler and is light enough to pretty easily slide on and off as needed. The dome itself is motorised using a little arduino, and a fairly heavily modified version of the "/juanmb/ArduinoDomeController" found on Github : effectively modified to use a stepper motor instead. This works very well and simulates the MaxDome II protocol so can use its ASCOM driver with N.I.N.A for autonomous control. There were a few challenges along the way, May, and its weather especially but really pleased with the way it has turned out and the way it is working. Minor issue with fairly considerable condensation forming on the pier and sometimes the mount but hoping some soil heater pipe around the pier will help, I guess just being the biggest lump of metal it will naturally be a cold sink but it needs sorting. The mount is really interesting. We have had it in the family 20 or so years. It was bought via freeads (who remembers that! an actual paper you had to buy from a shop containing categorised adverts you had to trawl through!) and we (my Dad and I) added a Sitech Servo system to it. That only very recently has failed, so has now been replaced with an OnStep DIY stepper motor system which I have to say, I am very impressed with (it even has a build in wireless server, so no control cable needed). We aren't at all sure of its background, but it looks strikingly similar to some of Rob Miller's creations and the Astro Promotions PM1 mount. Its BIG though, having a 9" 180:1 RA worm wheel in brass and a 6" 180:1 DEC wheel in brass. I'd never want to get close to testing its payload limits, but it came equipped with 34KG of counterweights, so I'm thinking its capacity is pretty generous. Modern times are great! The obervatory PC is an intel NUC mounted to the telescope, which means wiring is super neat, with just one power cable up to the telescope itself to worry about. I remote into the NUC using my laptop and control things from there. It is very early days, a slightly frustrating first night on Sunday due to Bluetooth and battling Windows power management. The dome is Bluetooth controlled, but Windows puts the bluetooth to sleep, which then locks up N.I.N.A, which then means bye bye imaging run and at 2AM that is a reasonable signal to call it a night. Sorted now through various registry tweaks - if anyone has similar issues let me know and I'll post details. Thanks all! Getting the main ballast hole dug along with the outer pad stones. Threaded rods for concreting in and bolting the pier down onto along with the main outer structure cobbled together. The cage should (I hope) add some reinforcement to the concrete but is not strictly rebar, it is one of those cages meant for putting stones/rocks in and building up walls or rockeries. So much cutting! Any normal person would have used a router and a circle cutting jig. I did try this but the bit kept working loose in the router (probably user error or a worn collet) and didn't fancy that spinning up into my face so moved over to the jigsaw. Now starting to draw interest from the neighbours, main dome structure completed. This was around the end of April, then May hit and we had rain pretty much for the entire month! This was my damn you May weather tent. A temporary structure built to house the dome for the rest of the build. This was a Jaws'esque "we need a bigger boat" moment. I bought the pipe on the left based on my Vixen GP mount, around 140mm diameter thinking that would be fine. Then got the measurements for the mount that would be being fitted, 300mm base! The pipe on the right is 240mm diameter, 7mm thick. You may recognise the colour if you do a lot of motorway driving - its an offcut of one of those poles used to support the "Don't Drink and Drive" signs. I do have another two peices left, each around 1200mm long if anyone is interested. Concrete going in. I was kindly loned the use of a cement mixer... which failed about a 1/3rd into the job. By that point I had to carry on so I became the power behind the cement mixer (they are surprisingly efficient at mixing concrete, so still easier to do that than mix it on a mixing tray). Subfloor in and the outer bottom structure getting completed. This was just a test of how well the 3.6mm plywood you can get would bend around the dome structure... very well it turned out. I think the trick is to "fair" the curve as best you can (I think its a boat term, just means an even curve with no bumbs etc). The plywood then just needs clamping either end and sits nicely to the ribs. Floor in and bottom plate for the pier drilled for the threaded rods. You can see the conduit for the cable runs, in the end mostly unused other than the 12V power cable. For the most part it is all 12V other than a few mains sockets in the nook. The one thing I thought I would really miss was, in the middle of the night dropping an eye piece cover or other small thing in the grass and never finding it. Wanting to retain that experience, fake grass was fitted as the floor surface. Primarily, I am hoping it acts as soft cushioning in case I do drop an eyepiece, but also as a bit of soundproofing just to keep any disruption to neighbours down, the houses are all fairly close. IMHO I think it works quite well. Bench test of the dome controller. This was when I was still debating a mechanical shutter hence the second motor controller. As you can see, not much too it! This ended up being slightly inspired. Corrugated cardboard was used for the templates. It worked really well, being corrugated, it only wanted to bend one way, which you could use to simulate the way the plywood would bend. It was dead easy to clamp an oversized bit on, draw around the inside of the ribs, account for the rib size and the templates were spot on. Too many boat repair videos watched! The skins were glued on from the inside using fillets of thickened epoxy. This meant you could take your time clamping everything up and aligning nicely before then applying the glue. The seems/edges were all filled with thickened epoxy, then fibreglass taped over. At this point, I was still playing with the idea of keeping it a natural wood finish with yacht varnish. Sanding, oh glorious sanding! That will be the takeaway from this project and the dome specifically I think, so so much sanding. First coat of the Dulux 3 part "system". Part 1 is I think a con, its basically boiled linseed oil sold at a premium. Primed, 2 coats of the most uncooperative paint I think I have used. It better be worth it, supposed to be 8 years. Its on! Shutter being built around the main opening. I was keen to keep the shutter skin all one piece to minimise plywood edges. The edges of the shutter and around where it slides were coated in a "special" tape. It is 3M poly tape, and I couldn't believe the price when I saw it retail - its over £1200, for a roll of tape! I still don't understand that, but suffice to say £25 on ebay and a few days later a roll arrived. To be fair, it does seem good stuff despite being just sticky backed, thick pastic bag. It stops the gloss on gloss contact and makes for a very smooth moving shutter. Actually, to the point where I used it around the outer edge of the support ring that forms the top of the octagonal structure, and it acts as a bearing surface for the main dome itself - the bottom skirt effectively rubs along it. Dead simple. Rocket pier prepared ready for welding, something I had never done before so a little apprehensive. Second ever weld trying stick welding, pretty happy with that, so a bit more practice and the pier was welded up. I learnt the hard way, never ever break a tap off in a critical piece of work. This was when tapping the holes in the 15mm steel top plate of the pier for the mount. This is a picture of it half way through drilling it out. Diamond tile hole saw bits were used to drill around the core, which luckily then just dropped out the bottom of the hole, leaving enough "meat" to finish, carefully, the tapping. About an hour and a half, and many diamond hole saw bits later! The tiny core from the broken tap can be seen on the left, so much fuss over such a tiny thing! Lighting and general wiring. There is a white light circuit comprising 4 LED strip lights, and a red light circuit comprising those fake EL light strips with LEDs in, which actually work really well. Both are independently dimmable and switchable. Everything is independently fused. 8AWG main supply and then 10AWG for the main branches from there (lighting, mount, telescope etc). The insulation is just an attempt to keep air flow to the bottom of the pier from under the observatory down, hopefully reducing the cooling effect and condensation. Lighting. The red glow is the EL LED strips, very effective when dark adapted. "Operations" area. The solar charge controller, mains plugs and 12V/30A power supply are housed here. OnStep controller completed. This is the STM32 Blue Bill version using TMC2209 stepper driver boards. Still some wiring (USB cables mainly) to complete below but the general impression is there. Its an Explore Scientific 102 FCD-100, with an SXVR-694... one can definitely not blame his tools!! A few of the mount prior to moving to the dome, compared to the Vixen GP for context. And one quick shot of the Horsehead and Flame taken on the Sunday. It was meant to just be a night to get polar alignment nailed, but I got carried away. Just 7, 3 minute frames through an SVBony 7nm H-Alpha filter... before Bluetooth went to sleep and locked up N.I.N.A The OnStep controller is working well. A few little videos, one of the dome seen moving from the outside, and one of a slew and the dome following suit. 10000000_909382853033030_1951611426406593040_n_414146070316544.mp4 10000000_606822893839078_3443595155924215202_n_803952740334938.mp4
  14. Well done! My biggest "fight" was formatting the cameraImageArray in the ASCOM driver so PHD2 showed something sensible. I wrote (hacked together) an ASCOM driver for a Sentech camera years ago and I am sure I remember falling down the same trap. The default ASCOM template creates a 2D array for cameraImageArray, which makes sense but after a few hours fighting with the order I populated the 2D array with pixel data, I gave up and just tried dumping it into a flat 1D array and PHD2 was perfectly happy with that (other applications may not be so leniant). The Pylon samples are good, but provide many options (aka rabbit holes) to choose - I'm going to treat it like a house of cards and now it is working leave it well alone! I don't claim to know what I am doing, which makes it all the more joyful when you start seeing recognisable images coming out of PHD2 All the best Chris
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