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Thalestris24

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Posts posted by Thalestris24


  1. 1 minute ago, michael8554 said:

    Higher Guide Rate helps mounts with large Dec Backlash.

    Although the mount has belt drive which removes the backlash due to the gearbox, the worm backlash doesn't look great according to the Calibrations so far.

    Michael

    Personally, as it's a brand new replacement mount and still appears to have the same issues as the original, I think I'd first look elsewhere for the source of the problems. I may be wrong but it just doesn't seem likely that two new belt-drive mounts would appear to have the same/similar problems.

    Louise

    • Thanks 1

  2. 1 minute ago, knobby said:

    Thanks Louise, target points very random, using oag so guide star fairly iffy but was round and value in PhD was 5.8 (best I could get it). Mount is nice and free so I'm fairly sure balance was good.

    Noticed another thread where @vlaiv suggests that a heavy scope needs the best tighter than the 2mm flex ? I've emailed Rowan to see what they suggest. Really appreciate your time helping 😊

    Remember, it has to be balanced vertically as well as in RA and DEC 🙂 . Always make sure guide star is not saturated and has a good snr (or best you can get). Not sure what you mean by "the best tighter than the 2mm flex" ?? So with oag what fl are you using in PHD2? I've never used either a oag, or a SCT, or other long focal length scope, so I don't know how good the guiding would be expected to be. I'm sure someone else on here will have had the appropriate experience 🙂.

    Louise

     

    • Thanks 1

  3. 5 minutes ago, knobby said:

    Starting to feel pretty despondent 😞 tried again last night, got nowhere fast, PA spot on in 20 mins (Sharpcap) quick align, calibrated PHD2 (With correct cam) usual dec backlash messages ... ran guide assistant, accepted suggestions and guiding up and down + and minus 2 or 3 ... well balanced, no cables flapping. Guess I'm really asking too much of the mount although others do use the combo successfully. I'm starting to wonder if it's just my seeing is too poor here. Good news is that this mount is better / more consistent than the one it replaced 👍 

    Hiya

    It might just be the seeing - what was tracking like with the Guiding Assistant (i.e. guiding off)? You shouldn't really be getting any backlash with a belt mod (I've said before, I'm sure!).  Calibration should be very good lines. I still suspect you may not be perfectly balanced. When you run PHD2 for a while are the points on the target clustered around the centre (good!) or to one side (bad!)? If to one side that indicates imbalance. Another possibility is guide scope flex if guide errors are random. What was your star profile and snr like?

    Louise

    • Thanks 1

  4. New tootsies came today :). They needed a couple of layers of tape to make a snug fit but I was expecting that. Of course, with the current arrangement I have no way of levelling on uneven ground so I'll have to stick to somewhere flat. It's still a little heavy for me to carry (I'm a wimp, I know) though I probably could just about manage it with a laptop and small battery in a backpack. I think the 16 gauge legs will be better in terms of weight but it could be several more weeks before I get them. The weather forecast is mostly cloudy anyway 😞

    TripodFeet_20pc.jpg.591310e24390a9f8bb797c96b4594069.jpg

    • Like 2

  5. 2 hours ago, nfotis said:

    Apologies if it has been already answered, but what's the rationale behind the rebuilding of the tripod with aluminium legs?

    Lower weight?

    Or do you want more stiffness compared to the old tripod?

     

    Regards,

    N.F.

     

    Lower weight, as discussed above


  6. I found I only needed a small sliver of tape on the tube to get a tight fit. That let me easily drill holes for the grub screws. Seems all very solid with the grub screws in. I'll assemble the legs on to the base and take a pic. There are (were!) these clear sort of washers where the top fitting goes into the base and the bolts go through. I can't see any real need for them so not bothering to replace for now.

    Louise


  7. Just now, MarkAR said:

    Hot glue sticks would work, might be worth warming the legs up a little so the glue doesn't set too quickly.

    I would say if you have the 10 gauge legs already then try them out first. If the weight is still too much then get the 16gauge. Using the hot glue will make it easier to remove when you need to.

    I've ordered the 16 gauge tubes now. Delivery time is a bit slow - could be a couple of weeks, so I can try the 10 gauge out first. I'll try some different things for holding the tubes in place and see what works.

    Cheers

    Louise

    • Like 1

  8. 1 minute ago, MarkAR said:

    The 16 gauge would be ok I reckon except for where the grub screws hold it, might get deformed and not hold very well.

    Ok, thanks. The grub screws aren't essential though with thinner metal I could easily drill some holes for them plus use tape, or possibly some sort of glue, to hold the legs in place. At the same time I don't want it to be too lightweight for imaging purposes. I suppose I could order the 16 gauge legs and try them out 🙂 . Might glue stick glue be good enough to hold the legs in place?

    Cheers

    Louise 


  9. Just to compare, I weighed the stainless steel legs plus extensions and cast bottoms, with the aluminium legs alone. The steel ones weigh 4.1kg, the aluminium weigh 2.2kg. So there is a fair saving. However, the Al tube I have are 10 gauge = 1/8" thick. There was the option of 16 gauge = 1/16" (1.59mm) thick walls. Clearly the thinner tubes would weigh half as much as the ones I have. I bought the 10 gauge to be on the safe side but would the 16 gauge do the job just as well? The only have to carry the EQ3 mount plus either a long lens with a GPCAM3 178M i.e. weighs 2.5 kg, or possibly an 80mm frac. The steel tubes are only about 1.1mm thick. The EQ3 mount + fittings weigh 8.1 kg, so the total payload from the point of the tripod legs is 8.1 + 2.5 = ~10.6kgs. Any thoughts / expertise on the strength of the two gauges of Al tube? If I can get it lighter still but still sturdy, that would be good 🙂.

    Thanks for any input 🙂 

    Louise


  10. 3 hours ago, MarkAR said:

    Well done Louise.

    For gluing back the new legs I would use construction adhesive. It'll easily fill any gap you have. You'd need to get a gun for it though.

    https://www.screwfix.com/p/evo-stik-sticks-like-sh-t-turbo-grab-adhesive-white-290ml/4072p

    For the feet I googled "rubber tube caps", Amazon has a good variety of possible items.

     

    I don't think I'll use glue, just in case I decide to go back to the stainless steel legs. Some tape should help make a tighter fit, plus grub screws. I'll see if I can drill some small depressions in the tube.

    Cheers

    Louise

    • Like 1

  11. Well the first one must have been beginner's luck ha ha. The other two did come off but I used the higher setting and more brute force. I think I'm about halfway through the great tripod rebuild project now. The replacement aluminium tubes are a slightly loose fit but I breathed a sigh of relief that they weren't slightly too large a diameter. I should be able to get them to fit ok either with the grub screws, or with some tape, else other glue. Some heavy duty adhesive tape should do it and may be the simplest solution. The other problem to solve is how to either fit the original pointy feet or how to fabricate replacements. I don't want to use the actual leg extensions as that would just add to the weigh and defeat the object somewhat. Hmm... There must be something commercially available, and fairly cheap? I'll have a browse.

    Louise

    • Like 1

  12. Update! #1 - success! Yay! Looks like I needn't have ordered the gloves or the solvent but they might come in useful for something else. Anyway, it only needed about 3-4 mins of gentle heating using the lowest (450 deg) setting. After it cooled I used a screwdriver through the bolt hole to revolve the fitting around the tube and it came off quite easily. Two legs to go! 🙂 

    Louise

    • Like 2
    • Thanks 1

  13. Not long back from picking up the heat gun from Screwfix 🙂. There was a short (socially distanced) queue outside but, fortunately, it wasn't raining. There was a young lady in front of me. She was eating what looked like sweets from a paper bag. She turned around and offered me one saying "I know this is weird, but..". I declined ("mustn't accept sweets from strangers! Ha ha"). She was probably just being friendly but I watched a program about Shauna [removed word] and the murder of Becky Watts the other day (amongst lots of others about serial killers, psychopaths and s. predators I've seen). She didn't appear to have the right Screwfix paperwork so wasn't allowed in and just walked away.
    Anyway, I digressed... I don't have the heat resistant gloves yet (not due before Saturday but you never know). I thought I could try just heating the end with the tube resting on the hob. Then letting it cool down again. Worth a try? I'll post an update later, if I'm successful!

    Louise

    Tut! It set the smoke alarm off! No obvious smoke but the alarms are very sensitive - my ears are ringing!


  14. 6 minutes ago, DaveL59 said:

    is there any slight gap between the leg and the part that's glued on?

    A coke can sliced to make a shim might be able to slide into the gap and slice the glue? Similar principle to opening padlocks if you know that technique (won't expand further here on a forum tho)

    If there was a gap the pieces would come apart easily. I'll pick up the heat gun tomorrow and give it a whirl.

    Louise


  15. 3 minutes ago, MarkAR said:

    Depends on the glue really, if it's a mastic rubbery style it might soften up enough. An epoxy might as well.

    Can you see any traces of glue from the one you have removed?

    Yes, as I said, it's similar to the Meade above. It's not mastic.

    Louise

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