Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

sgl_2019_sp_banner.thumb.jpg.a0ff260c05b90dead5c594e9b4ee9fd0.jpg

Lonestar70

Members
  • Content Count

    636
  • Joined

  • Last visited

Everything posted by Lonestar70

  1. Hi Chris, On reasonably smooth surface 1ltr of PVA should be enough for around 64 sq ft of contact surface. For your 4 outside frame joints you will only have around 25 sq ft.... spread a thin layer over the whole surface using an old straight knife or the back of a hacksaw blade and assemble straight away... it starts to set off pretty quickly. I would buy a couple of 1ltr bottles at that price as I am sure you will need to glue up lots of other joints etc. It Keeps well in a coolish place if well sealed. Keep happy.
  2. Hi Chris, M8 would just about be ok... 10mm would be much better. Don't forget... you also need the large dia washers or square metel plates to bolt up against. the ones for the head end have a square hole... the nut side has a round hole. The down side to this method will mean the heads, plates and nuts stick out from the surface which might be a problem for your cladding. At least Screws and Glue will eliminate this problem. Choice, Choices!!!! Keep happy.
  3. Hi Chris, 80mm screws on their own would not provide sufficient sheer capability... used in conjunction with gluing the boards together would be adequate for your use. When gluing... clamp the boards together and fit screws whilst clamped. Have you seen the price of waterproof PVA??? Keep Happy.
  4. Hi Gina, I had a look on the internet and found some details of focal length for the ASAHI PENTAX LENSES. This is specified as 45.5mm Flange focus distance... This being the distance required between the rear flange of the lens and the front face of the camera sensor, and the lenses use an M42 x 1mm attachment thread. The ATIK site states 13.1mm from front of camera flange to sensor with T2 thread (M42 x 0.75mm) So, with these figures in mind I drew up a possible filter wheel housing using 3mm thick sideplates and has 20.4mm of available inside width... this should be more than enough to fit the carousel and drive mechanism even with the 8mm thick filters. Auto Filter wheel_1.pdf The lens side adaptor should allow you to screw your lens in directly without need of any other adaptor. The Camera adaptor is a direct attachment for the ATIK. Both are custom adaptors which could easily be made. What do you think? Best Regards.
  5. Hi Gina, Correct me if I am mistaken, but I seem to recall (from one of your many threads on camera spacing) that you had to add an 8mm or perhaps a 10mm extension spacer between the EFW and the Atik to obtain the correct back focus distance. It may have been in relation to using the Atik a EFW with your ED80... which requires 55mm behind the FF/FR. If this is so, and your camera lenses are of similar backfocus requirements... then you could add the 8mm-10mm to the width of the new filter wheel and do away with the external extension... just a thought. Best regards.
  6. Hi Chris, Yes that would be fine and it makes the boards easier to handle (2" not as heavy as 4"), however, it would be normal practice to bolt them together using coach bolts and large washers( or bearer plates ). On 6" wide timber you need 2 rows of bolts... a top row say 2" down from the top and pitched at about 2ft intervals. A second row 2" from the bottom also spaced at about 2ft intervals but offset by 1ft from the top row... you end up with a sort of zig-zag pattern. The reason for bolting them like this is to more evenly spread the tensions through both and minimise each board warping in a different direction to it's partner. Some buildings I have seen glue the 2 boards together and put 1" dia pegs through both boards in much the same pattern. Hope that all makes sense. Best Regards.
  7. Looking good Chris... just one cautionary suggestion though. From you Sketchup drawing it would appear that you are proposing to use 4" x 4" (100mm x 100mm) for the floor supports. This is not good engineering practice when spanning best part of 8 - 9 ft between concrete supports... they will almost certainly bow downwards between the pillars when any weight is applied to the internal floor. You would be best using at least 6" x 3" (or even 6" x 4") for the outer frame with 6" x 2" minimum for any remaining floor support joists (these can be attached to the outers using metal joist hangers. Be sure and use pressure treated (tanilised timber) not ordinary (interior grade) timber. Keep up the great work. Best regards.
  8. Hello Chris in the SE of Oz, from the West Coast of Scotland... welcome to SGL. Clear Skies.
  9. Hi Jaccord , welcome to SGL. Some great dark sky sites up there in upstate NY . Best regards and Clear Skies.
  10. Hi from a soggy West Coast of Scotland and welcome to SGL. Plenty of help here if/when you need it... just ask. Best regards and clear skies.
  11. Hi Nikolaj and welcome to SGL. With your 2 scopes and a great mount you are set up for pretty much any kind of viewing, and you could even get into astrophotography with your 4" APO Refractor if you felt the urge to venture over to the dark side clear skies.
  12. Lonestar70

    New member

    Welcome to SGL Starbright. The loss of a loved one is hard to bear at any time and always leaves a huge hole which can never be filled, My Condolences. I hope you find a good scope etc soon. Clear Skies.
  13. Hi Gina, You certainly get yourself involved in some interesting DIY stuff. I like the idea of the inverted belt, however, you appear to have a groove around the outside of your carousel... was this for a drive belt? One problem you might run into is securing the inverted belt since it will only be supported at 2 points across it's width... placing external tension on this (with another, larger dia belt from the motor) will almost certainly lead to the rim belt collapsing into the groove... I think you would need to fill this with something (car body filler or epoxy) before you fit the inverted rim belt... I presume you will be glueing this in place? How are you intending to Index the filter positions using the Arduino? are you intending to have a sensor at each position with a home position sensor as reference?.. or perhaps some form of quadrature encoding? I can see, what appears to be a single hole for a reference (pos home position sensor) but do not see any others. How thick is your carousel wheel? and how deep is the recess for the 36mm filters, also what is the (clear) inside diameter of the filter holes?... I am assuming that the outside dia of the filters you have is 36mm. I may be able to help you with the required 1 1/4" - 36mm adaptors, and any other bits you need turning. Pm me a sketch of what you require and your email address and we can discuss it off-site in more detail. Best regards.
  14. Hi All, The important thing to remember, when thread cutting METRIC threads on an IMPERIAL machine, wheather you use motor power or hand power to turn the spindle, is to not disengage the feed (half nuts on the leadscrew) until the thread is complete***. This method will always work wheather you have a threading dial fitted or not. Threading large holes in a plate can also be done if you have enough clearance in your lathe bed to enable the workpiece to rotate when attached to a faceplate. Not difficult when the hole is in, or close to, the centre, however, multiple holes which are located around the centre (as is the case with the filterwheel) would mean quite a large off set of the plate. This now means the plate is rotating eccentrically and will require considerably more bed clearance... not very likely unless you have a very large GAP BED lathe available. For heavier pitch threads (Metric or otherwise... Say 2mm pitch or 10 tpi or larger), where the depth of thread is greater, it would be better to use the method where the compound slide is set at half the included angle of the threadform since this will reduce the loading on the cutting tool (especially if using hand power)... this method uses the Cross slide to advance/retract the tool to the ZERO position (the outside or inside edge of the work) and uses the Compound slide to apply the cut depth... but that is for later. :evil: *** There is a method on an imperial machine with a thread dial fitted (specific note must be made of the number on the thread dial when the leadscrew is first connected before any threading begins), but it requires a lathe where the spindle can be stopped very quickly when the motor power is turned off, usually involving a fast spindle brake,immediately after the leadscrew is disconnected, specific note is made of the overun of the thread dial which is then corrected for by turning the spindle in reverse... the carriage is then returned to the start position and the leadscrew re-engaged with exactly the same number showing however, for most home workshop lathes, which often don't have a thread dial fitted, or a spindle brake, this can not be used easily, or without running the risk of error.... For home use it's much easier and error free just to leave the leadscrew connected. Incidentaly... the same rule applies when cutting Imperial threads on a Metric Lathe. Keep happy... and I look forward to seeing both your respective completed filter wheels.
  15. Hi Jason, Very well done... I told you it was easier than you thought... No stopping you now Best Regards
  16. Hi Kev, and welcome to SGL. Ask all the inane questions you like, there will always be someone to help and advise. clear skies (yes you do get the odd one or two in London)
  17. Hi Dave and welcome to SGL. Setting up a business takes a great deal more effort than most people realise and often the first year or two you feel you are working for nothing as the bills keep rolling in, but the turnover doesn't keep up, and there is always the next things to purchase and get set up. At least you are past that stage now with yours. You will soon get back into the swing of things with your astronomy... I wish you the best in both ventures.
  18. Hi hgriffin1 and welcome to SGL. Sounds like you have found a nice piece of hardware there and you should have some nice dark sky locations around your area in which to get the best from it. I have made upwards of 40 visits to CT (work related) and away from the bigger towns/cities ( Hartford, Stamford, Norwalk, Danbury etc) I always saw some great skies and wished I had a scope with me. I was blown away by the skies up around Litchfield Hills, Mount Frissnell and Bear mountain... Lots of nice horses up that way too. Enjoy your find. Clear Skies.
  19. Lonestar70

    New member

    Hi Mike and welcome to SGL. That's a nice scope and mount combo you are getting and it will give you some great views. It will also be perfect for Deep space Astrophotography if you choose to go that route later. Enjoy. Clear skies.
  20. Hi Jules, Yes I suppose that is one way to get your camera mounted, at least it won't mean spending large sums of money. My main concern is why you need to be so close in with the PDS and the idea of finding where the SCOPE mirrors focused relative to the focuser was to try and determine if there was a possible problem with your particular unit. Hence the paper test and measurements I suggested. As has been said, by many of the other guys, it seems very odd that you should need to be that close in with a 20mm back focus camera when others, including me, can get focus with 10mm - 20mm of spare INWARD travel when using cameras of 46mm - 55mm back focus requirement... this just not add up. Anyway, you have a plan and it is worth trying... If you have any problem finding someone to turn down the addaptor body for you... give me a shout (on here or via PM) and I will be happy to do it for you on my lathe... No Charge... other than the small amount of postage involved. Keep us informed. Best regards.
  21. Hi Jules, Well I think that might just be far enough away Ok, try this... take the camera away and just leave the sw adaptor in the focuser. Get a piece of tracing paper, or thin white paper, and tape it to the outer end of the adaptor. Point the scope at the moon and adjust the focuser for the smallest white dot... you should be able to see this through the paper. This will tell you where the focal point of the telescope is in relation to the end of the focusers fixed body... so measure this distance. Your camera focal plane need to be behind this length (Further out) by a few mm to allow the picture to cover the sensor. If you also subtract from this distance the thickness of the top of the sw adaptor this will give you the available inward travel from the point of focus. Once you know where the telescope focal point is you should be able to figure out the length of the required fittings to mount the camera... and as long as this length is less than the available focus travel by say10mm or so then you should be able to reach focus with a little to spare. This is a very strange situation. Best regards.
  22. This is very odd... I use a Nikon D90 an my 150PDS with a 2" - T2 nosepiece screwed into the T-Ring and this comes to focus with around 15mm of In Travel still remaining. The D90 has a back focus distance of 46.5mm... wherase your camera only requires 20mm... this would suggest you needed to be further out ( by 26.5mm )... not closer IN.... all very odd!!. Silly question... but what are you using as a target for focusing?... the 150 does not like to focus on things much closer than a mile away. Best regards.
  23. Hi Jules, How does part A attach to your SW adaptor?... does it use the T2 thread? If so then you might try unscrewing part A from part B... then screw part B straight on to the SW adaptor... this would buy you the length of Part A as extra In Travel... it Might just be enough and won't cost you anything to try. Don't get to downhearted my friend... we have all shared similar experiences with various astro gear and I am sure we will get you sorted for imaging between us. Failing that... the TS adaptor I linked to would buy you an additional 20mm or so on top of the above extra travel. Hope this makes sense. Best regards.
  24. Hi Jules, It is not clear from your photos, but I suspect that your camera adaptor is the one designed to allow connection of T2 threaded lenses to your camera... hence it's long length... this is to allow such lenses to reach focus with a 55mm backfocus. your camera has a back focus of 20mm so for astro work you need a shorter adaptor such as this one: - http://www.teleskop-express.de/shop/product_info.php/info/p3676_T2-ring-for-Micro-Four-Thirds--Panasonic--Olympus-.html This is designed to perform both functions and you would need to use it without the extension. Instead you would use either the 11/14" -T adaptor: - http://www.teleskop-express.de/shop/product_info.php/info/p201_TS-Adaptor-1-25--to-T2---Focal-Adaptor-for-1-25--Focuser.html Which I think you already have, or the 2" -T adaptor: - http://www.teleskop-express.de/shop/product_info.php/info/p200_Adaptor-2--to-T2---low-profile.html either would fit straight into your focuser. I would suggest the 2" version since this will reduce/eliminate any Vignetting. both are threaded for filters. The one you have at the moment would probably work Ok with the SW Coma corrector, since this needs the 55mm back focus distance. Hope this helps. Best regards.
  25. Hi Gina, No problem Gina... we all have to help each other where possible. Well at least you have found the main problem with CdC... Clock Time wrong... I had the same issue until I realised that the windows time routine was Rubbish... and changed it to the same one you have chosen. as for GPS... I don't think CdC can read directly from a GPS receiver (but I will stand correction on this if there is a way)... at least I never found a way... what I did was start ASCOM/EQMOD from CdC and get ASCOM/EQMOD to read the GPS, I then opened CdC's setup>observatory and typed in a suitable location name and manually entered the GPS co-ordinates as read from ASCOM/EQMOD... I then told CdC to save the location file. CdC will read this on the next startup and the co-ordinates will be correct. I am sorry to hear that it has stopped working again... have you got any USB2 ports on your new laptop?... I have read several reports of ASCOM, and other astro programmes, not working as expected when trying to use USB3... this may be an ASCOM/or other Driver problem since I believe most of these drivers were written for USB1.1 and USB2... I know USB3 is supposed to be backward compatible but it would seem this is not the case for some implimentations... judging by the number of failures read about. I would try a USB 2 port if you have one. Hope this helps a bit more. Best Regards and enjoy your imaging session... it's still very cloudy up here
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.