AstronomyUkraine Posted May 3, 2021 Share Posted May 3, 2021 I had everything set up for an evenings imaging, when near disaster struck. I was in the process of polar aligning the mount, and was just giving the lower latitude bolt a final tweak. Immediately I felt something was not right, there was no tension on the bolt, it was turning too easily, next moment the telescope shot forward, luckily I had hold of it, and it was securely in the saddle. What happened, the latitude bolt had stripped the threads in the mount. My solution is to drill the hole with a 10mm drill, and tap a new thread to take a 90mm x 12mm x 1.50 class 10.9 bolt. I will replace both of the crappy skywatcher latitude bolts. I dread to think what could have happened had the bolt give way during slewing or imaging. I'm not very happy, but it could have been a lot worse, and a more expensive fix. Brian 1 2 Quote Link to comment Share on other sites More sharing options...
GazAstro Posted May 3, 2021 Share Posted May 3, 2021 Ouch, lucky that nothing else was damaged ... It's crazy that they're still designed that way ! 1 Quote Link to comment Share on other sites More sharing options...
AstronomyUkraine Posted May 3, 2021 Author Share Posted May 3, 2021 20 minutes ago, GazAstro said: Ouch, lucky that nothing else was damaged ... It's crazy that they're still designed that way ! Yeah, steel bolts into an aluminium thread is a poor design fault. Hopefully it should be a simple fix that will last another few years. Quote Link to comment Share on other sites More sharing options...
rwillits Posted May 3, 2021 Share Posted May 3, 2021 I would look into "Helicoil" thread repair kit. They replace the striped threads. The kit comes with a drill, tap, insert tool, and helicoil threads. They look like a small spring. drill out the old threads, tap new threads, and insert the coil and finished. many racing mechanics will take a new aluminum engine and replace all the original threads with "Helicoil" threads. Here, they are found at auto repair stores or online. I have used them for years. 2 Quote Link to comment Share on other sites More sharing options...
rwillits Posted May 3, 2021 Share Posted May 3, 2021 The drill may not always come with the kit. If not buy it seperate. 1 Quote Link to comment Share on other sites More sharing options...
Marmot Posted May 4, 2021 Share Posted May 4, 2021 A very worthwhile post: not only is it of interest as to the solution, but it makes others aware of a ‘weak link’ and could therefore prevent others suffering the same fate. I would imagine the ‘steel bolt in an alloy thread’ will apply to other Skywatcher mounts and not just the EQ6. thanks for the post. martin 1 Quote Link to comment Share on other sites More sharing options...
AstronomyUkraine Posted May 4, 2021 Author Share Posted May 4, 2021 8 hours ago, rwillits said: I would look into "Helicoil" thread repair kit. They replace the striped threads. The kit comes with a drill, tap, insert tool, and helicoil threads. They look like a small spring. drill out the old threads, tap new threads, and insert the coil and finished. many racing mechanics will take a new aluminum engine and replace all the original threads with "Helicoil" threads. Here, they are found at auto repair stores or online. I have used them for years. Thanks for the info, sounds like a great solution to the problem. Unfortunately there are no kits available here, and getting one from China is a 4 week wait. Quote Link to comment Share on other sites More sharing options...
AstronomyUkraine Posted May 4, 2021 Author Share Posted May 4, 2021 1 hour ago, Marmot said: A very worthwhile post: not only is it of interest as to the solution, but it makes others aware of a ‘weak link’ and could therefore prevent others suffering the same fate. I would imagine the ‘steel bolt in an alloy thread’ will apply to other Skywatcher mounts and not just the EQ6. thanks for the post. martin My mount is 15 years old, and has had a lot of use over the years. Obviously the infamous bolts on EQ mounts with their inability to adjust the latitude easily, has caused wear on the threads in the mount. Quote Link to comment Share on other sites More sharing options...
TerryMcK Posted May 4, 2021 Share Posted May 4, 2021 a bullet dodged there Brian. Thankfully you have been able to fix it. 1 Quote Link to comment Share on other sites More sharing options...
paulgrover68 Posted May 4, 2021 Share Posted May 4, 2021 Lucky escape - as someone who has had a fair few EQ6 issues this I feel your pain. I think the takeaway is that with the EQ6 it's not a case of if... it's when. Hope it all pans out okay. 1 Quote Link to comment Share on other sites More sharing options...
AstronomyUkraine Posted May 4, 2021 Author Share Posted May 4, 2021 1 hour ago, TerryMcK said: a bullet dodged there Brian. Thankfully you have been able to fix it. The cure is a lot cheaper than a replacement mount, scope, or both. I decided to wait for a helicoil kit, it seems the best solution, if they can hold down a cylinder head, a mount should be no problem. I'm going to replace the terrible Skywatcher bolts with M10 titanium hex socket bolts. I will need to use an allen key to adjust the bolts, but I don't see it as a problem. The latitude won't change much between sessions. 1 Quote Link to comment Share on other sites More sharing options...
AstronomyUkraine Posted May 4, 2021 Author Share Posted May 4, 2021 49 minutes ago, paulgrover68 said: Lucky escape - as someone who has had a fair few EQ6 issues this I feel your pain. I think the takeaway is that with the EQ6 it's not a case of if... it's when. Hope it all pans out okay. I think Skywatcher mounts are designed by a committee, the cheaper ones certainly have a lot of issues regarding design and materials used. Quote Link to comment Share on other sites More sharing options...
AstronomyUkraine Posted May 4, 2021 Author Share Posted May 4, 2021 11 hours ago, rwillits said: The drill may not always come with the kit. If not buy it seperate. I found a kit with everything in it I need. Only cost 11 euro, but I have to wait until the end of May to get it. 3 Quote Link to comment Share on other sites More sharing options...
MarkAR Posted May 4, 2021 Share Posted May 4, 2021 A lucky escape, could have been a pricey disaster. 1 Quote Link to comment Share on other sites More sharing options...
AstronomyUkraine Posted May 4, 2021 Author Share Posted May 4, 2021 (edited) 5 hours ago, MarkAR said: A lucky escape, could have been a pricey disaster. You are not joking, I was so lucky to be standing at the side of the mount when it failed. Another two minutes I would have been slewing to the target. I would advise anyone with a Skywatcher mount to check for any sign of lateral play in the latitude bolts, it could be a sign the thread are being stripped. Edited May 4, 2021 by AstronomyUkraine Quote Link to comment Share on other sites More sharing options...
Carastro Posted May 4, 2021 Share Posted May 4, 2021 Yikes. Are these the original bolts that came with the mount? Carole Quote Link to comment Share on other sites More sharing options...
AstronomyUkraine Posted May 4, 2021 Author Share Posted May 4, 2021 15 minutes ago, Carastro said: Yikes. Are these the original bolts that came with the mount? Carole Yes Carole, but the bolts are fine. What happened is the threads inside the mount have been stripped. With the mount being made of aluminium it is softer than the steel bolts. I can fix it so it is better than it came out of the factory, so thankfully no harm done, except for the inconvenience. Of course since it happened, I have had two clear nights, but it could have been worse. Brian Quote Link to comment Share on other sites More sharing options...
AstronomyUkraine Posted May 11, 2021 Author Share Posted May 11, 2021 Update! Since having this mishap with my mount, the weather here has been great, 6 out of 7 clear nights. I reckon I have lost around 35 hours of imaging time, tonight is also going to be clear. It will be another week at least before I receive the tools needed to do a good repair on the mount. I wish I had just drilled out the hole, tapped it for a 12 mm bolt, and left it at that, except the same thing could happen again. At least with a steel insert, the threads won't get stripped. Brian Quote Link to comment Share on other sites More sharing options...
AstronomyUkraine Posted May 19, 2021 Author Share Posted May 19, 2021 My mount is now operational again. I drilled out the offending holes and tapped them to take a 10mm thread insert. At the moment I just have an ordinary bolt in the altitude adjustment, but I can adjust it with my fingers even carrying my rig, so that is a good sign. Just waiting for some clear sky now to adjust the altitude correctly. I have also installed a new ZWO EAF, so that will need adjusting too. 4 Quote Link to comment Share on other sites More sharing options...
Marmot Posted May 19, 2021 Share Posted May 19, 2021 Glad you managed to resolve it with a DIY fix. Hopefully it’s now good for another few years🙂 Quote Link to comment Share on other sites More sharing options...
AstronomyUkraine Posted May 19, 2021 Author Share Posted May 19, 2021 40 minutes ago, Marmot said: Glad you managed to resolve it with a DIY fix. Hopefully it’s now good for another few years🙂 It was quite a straightforward fix. A couple of helicoil thread inserts, a drop or two of loctite just as an added level of security, and the job was done in 20 minutes. I lost about 40 hours of clear skies due to the mount, now that it's fixed, it's raining of course. Quote Link to comment Share on other sites More sharing options...
MartinS Posted May 23, 2021 Share Posted May 23, 2021 I fitted the NEQ6 rail kit from Dark frame to my current and previous NEQ mount. This simple kit is easy to fit and it transforms the operation of the Latitude arrangement, removing a lot of the stress and weight on the latitude bot, which causes the tread to strip. With my NEQ6 used for mobile operations the kit has greatly improved the PA operation with fine Lat adjustment now possible. 2 Quote Link to comment Share on other sites More sharing options...
AstronomyUkraine Posted May 24, 2021 Author Share Posted May 24, 2021 19 hours ago, MartinS said: I fitted the NEQ6 rail kit from Dark frame to my current and previous NEQ mount. This simple kit is easy to fit and it transforms the operation of the Latitude arrangement, removing a lot of the stress and weight on the latitude bot, which causes the tread to strip. With my NEQ6 used for mobile operations the kit has greatly improved the PA operation with fine Lat adjustment now possible. I have had the rail kit on my mount for 6 months now, but my mount is 15 years old, and has taken a lot of abuse in that time. Now everything is running smooth again. 1 Quote Link to comment Share on other sites More sharing options...
woodblock Posted June 4, 2021 Share Posted June 4, 2021 I have an HEQ5. I do the polar alignment without the scope and counterweights fitted. I started doing it this way because I have to move the kit in and out of the shed each session and it's easier to move the mount and scope separately. So I move the mount into position, do the PA and then fit the weights and the scope. But as it happens I think it makes the altitude adjustment a little easier without the extra weight on board. Someone gave me that advice early on. I think it might also reduce the wear on the threads. I have marks on the base so I know where to place the scope and I only have to make a very small adjustment to get the PA done. I've replaced the lower adjustment screw with one with a ratchet style handle which is easier to use but I have to use it without the polar scope cover fitted. Having said that, the altitude adjustment on the HEQ5 is pretty awful. Also good tip about the Helicoil. Cheers Steve 2 Quote Link to comment Share on other sites More sharing options...
AstronomyUkraine Posted June 4, 2021 Author Share Posted June 4, 2021 10 hours ago, woodblock said: I have an HEQ5. I do the polar alignment without the scope and counterweights fitted. I started doing it this way because I have to move the kit in and out of the shed each session and it's easier to move the mount and scope separately. So I move the mount into position, do the PA and then fit the weights and the scope. But as it happens I think it makes the altitude adjustment a little easier without the extra weight on board. Someone gave me that advice early on. I think it might also reduce the wear on the threads. I have marks on the base so I know where to place the scope and I only have to make a very small adjustment to get the PA done. I've replaced the lower adjustment screw with one with a ratchet style handle which is easier to use but I have to use it without the polar scope cover fitted. Having said that, the altitude adjustment on the HEQ5 is pretty awful. Also good tip about the Helicoil. Cheers Steve My rig is split into two. I have the mount and weights, and the OTA. All that I need to do is attached a couple of cables. I never polar align without the OTA attached to the mount, you tend to lose alignment once the extra weight is added. There are workarounds to make the alt adjustment easier, I used the EQ6 rail kit on mine. I bought it from Modern Astronomy, it makes adjusting the alt a doddle, even with my 120 refractor on it, and 11kg of weights. There is also a version for the HEQ5 from Dark Frame Optics, not overly expensive, in astro terms. Brian https://www.darkframeoptics.com/product/heq5-rail-kit 1 Quote Link to comment Share on other sites More sharing options...
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