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Eq3 mount azimuth bolts stiff


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Hi all - I'm having a huge amount of trouble with my Skywatcher eq3 mount - firstly are the azimuth bolts (0-90 degrees) supposed to be ultra stiff?? Ive got arthritis and it hurts my hands a lot just move them a bit. And when it does move it moves jerkingly not smooth. Also the two front bolts for left right even when tight the mount can move a bit left/right. You can imagine this makes polar alignment very hard and it must come off polaris easily. Also I can't align the polar scope because I simply can't get the mount to drop any further down than about 45 degrees. I don't really understand what I'm doing wrong. Its depressing because I'm missing many clear nights because of it. Any help would be great!

frank

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do you mean altitude bolts? if eq3 is as bad as eq5 you need to take the load off the bolts before turning them. some suggestions:

- align only once, use bubble level to level the mount and turn it to point it north. mark the places for the legs. 

-do you need accurate alignment? are you doing visual or AP? for visual astronomy alignment doesnt need to be so accurate. 

-bolts also stiffen when they get bent, atleast the eq5 bolts tend to get bent if you are not careful. 

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You really do have to watch how much pressure you use when adjusting these bolts as they bend then either snap leaving the thread in the mount or get so wedge you can't remove it. Always take the weight off the direction your wanting to adjust to IE: hold the counter weights or hold the scope and always undo one side before tightening the other.

As for the DEC bolts once you have aligned you will probably remove the slack that remains there by tightening the bolt that attaches the mount to the tripod.

Hope this helps.

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There have been many problems with SW bolts, to be perfectly honest they are not of good quality material, often termed bendy bolts. If you can remove completely the Altitude bolts, as it sounds like you may have damaged ends which are digging into the casting, causing the jerking, every time you try to adjust them. these should be replaced with good quality stainless ones or at best quality galvanised steel, with a suitable adjustment knob to suit. Measure across the diameter of the bolt for size, but in all probability they will be M8. You should, however, make sure in adjusting, that you slacken off the opposing bolt before trying to adjust the opposite one. The same goes for the Azimuth adjustment bolts, replace and well grease. If the mount has stood for some time, there could be a small amount of corrosion between the thread of the casting and the bolt, causing them to become very stiff :)

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There have been many problems with SW bolts, to be perfectly honest they are not of good quality material, often termed bendy bolts. If you can remove completely the Altitude bolts, as it sounds like you may have damaged ends which are digging into the casting, causing the jerking, every time you try to adjust them. these should be replaced with good quality stainless ones or at best quality galvanised steel, with a suitable adjustment knob to suit. Measure across the diameter of the bolt for size, but in all probability they will be M8. You should, however, make sure in adjusting, that you slacken off the opposing bolt before trying to adjust the opposite one. The same goes for the Azimuth adjustment bolts, replace and well grease. If the mount has stood for some time, there could be a small amount of corrosion between the thread of the casting and the bolt, causing them to become very stiff :)

Thanks everyone. My arthritis has given me a left index swan neck deformity which means it is very hard to turn anything stiff with that hand. Also my middle right finger is going that way too so I need to have easy tweaking. So the best suggestion is to take out the original SW bolts and replace? Any ideas of where to get M8 bolts from? It's weird about the underside bolt, it can't tighten all the way up because the mount came with a metal plate with a hold in one end (which the underside bolt goes through and then into the mount) and a metal "cup" on the other that the power supply slides onto rather than being velcroed to the legs. But the plates thickness means that the bolt does not screw all the way in. The whole idea of turn one then the other bolt messes with my head too lol. 

frank

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Thanks everyone. My arthritis has given me a left index swan neck deformity which means it is very hard to turn anything stiff with that hand. Also my middle right finger is going that way too so I need to have easy tweaking. So the best suggestion is to take out the original SW bolts and replace? Any ideas of where to get M8 bolts from? It's weird about the underside bolt, it can't tighten all the way up because the mount came with a metal plate with a hold in one end (which the underside bolt goes through and then into the mount) and a metal "cup" on the other that the power supply slides onto rather than being velcroed to the legs. But the plates thickness means that the bolt does not screw all the way in. The whole idea of turn one then the other bolt messes with my head too lol. 

frank

I assume you are referring to the Altitude adjustment, no matter which of the two screws you turn, if you do not slacken off the opposing bolt, you will do nothing but cause damage to the bolt you are turning and the internal casting. Often the cause of many bent bolts and damaged castings. As far as I am aware, you can buy sets of replacement stainless Altitude bolts for your mount from Astro suppliers, I can`t remember which, but I am sure someone will give you the information. If it is a matter of your central bolt not tightening, not quite sure whether you mean with the thickness of the plate, the bolt is not now long enough, in which case a longer bolt is needed. You could try not using the plate and revert to the original set up and Velcro your power supply to the legs, but if you want to try a longer bolt, a good hardware shop should be able to supply what you want, take the original bolt with you HTH :)

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You may also be able to find a set of bolts that are easier for you to turn.  Perhaps with a large knob, or with a spring-loaded "handle" that can be disengaged from the bolt that allows it to be used in a similar manner to a ratchet drive.

James

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Thanks everyone. My arthritis has given me a left index swan neck deformity which means it is very hard to turn anything stiff with that hand. Also my middle right finger is going that way too so I need to have easy tweaking. So the best suggestion is to take out the original SW bolts and replace? Any ideas of where to get M8 bolts from? It's weird about the underside bolt, it can't tighten all the way up because the mount came with a metal plate with a hold in one end (which the underside bolt goes through and then into the mount) and a metal "cup" on the other that the power supply slides onto rather than being velcroed to the legs. But the plates thickness means that the bolt does not screw all the way in. The whole idea of turn one then the other bolt messes with my head too lol. 

frank

Tighten the mount first then the tripod spreader ;)

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I find that at my latitude and with lightweight equipment that i dont need the north facing bolt done up at all it is left set at a few degrees away from the PA position and any adjustment done with the other bolt.

The problem i would have with a replacement or longer bolt is that it would get very close to my polarscope interfering with the view.

Alan

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Thanks everyone. I'll post a photo tomorrow to show what I mean re the underside bolt. Lol yes 51 degrees for Horsham but I was trying to do a polarscope to mount alignment (ie cross hairs on a tv aerial or such like so the mount needs to be pointing fairly low. Ive seen a few scopes with black twist handles on long bolts instead of the very fiddly t-type.

As for slacken one then turn the other, is this supposed to be an easy job because from day one (got the scope about a year ago), it has been nigh on impossible to turn one to slacken to allow the other to move. Or you can undo the front one quite a bit but the back one can hardly move. Hard to describe. :/

Frank

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Hi

I would suggest removing the mount from the tripod altogether (undo all adjustment bolts first) and then check whether the adjustment bolts can screw in and out freely. If they don't you'll have to investigate why not. As mentioned above these bolts do tend to bend... Also, do make sure the central mount tightening bolt is engaging properly with the mount  thread when reassembling. This can be quite tricky to do but it's suddenly obvious when it's going  in ok. Don't overtighten though as the mount needs to be able to move via the azimuth adjustment.

Htth

Louise

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Hi Frank,

If these altitude adjustment bolts have always been very stiff to move then perhaps the problem lies in the altitude spindle bearing.

Under the 2 black covers on the side of the mount there is a long bolt which passes through the head... this bolt is adjusted during manufacture and the plastic covers are fitted over it.

Some people have found the factory adjustment has been too tight and they have needed to slacken it off a small amount.

Unfortunately, the plastic side covers (which are glued in place) are somewhat fragile and are not easy to remove without damage... it can be done by sliding a thin sharp knife blade under an edge and working it round the joint, but takes great care.

You will need to remove both covers as the bolt and the nut need to be got at to make the adjustment.

From the way you describe the stiff altitude adjustment bolt problem remaining, even with one altitude bolt backed right off, then that suggests the bearing bolt is the culprit.

If you remove both altitude adjustment bolts you should be able to swing the head through it's full 90deg travel by hand... there should be some drag, to prevent it just falling under it's own weight, but this should not be excessive.

If the head is very stiff to move in this manner, then the bearing bolt is too tight.

Hope this helps.

Best regards.

Sandy. :grin:

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Thanks everyone. I'll post a photo tomorrow to show what I mean re the underside bolt. Lol yes 51 degrees for Horsham but I was trying to do a polarscope to mount alignment (ie cross hairs on a tv aerial or such like so the mount needs to be pointing fairly low. Ive seen a few scopes with black twist handles on long bolts instead of the very fiddly t-type.

As for slacken one then turn the other, is this supposed to be an easy job because from day one (got the scope about a year ago), it has been nigh on impossible to turn one to slacken to allow the other to move. Or you can undo the front one quite a bit but the back one can hardly move. Hard to describe. :/

Frank

Hi Frank

I'm a beginner myself and have only had my scope for a couple of weeks but reading your posts I get the impression (I could be wrong) that you don't understand what bolts do what. The bottom bolt which protrudes between the tripod legs has a handwheel nut which secures the mount to the tripod then you slide on your spreader plate and another handwheel nut tightens up and spreads the tripod legs. As someone said earlier leave these bolts slightly loose when you adjust your latitude and altitude bolts. Then tighten them when your finished. The latitude and altitude bolts work against one another by pushing on the same adjuster, this is why you need to slacken the bolt in the direction you want the mount to turn before you tighten the opposite bolt. The altitude bolt which raises the mount takes a lot of weight when your your increasing the altitude so it pays to take the weight off the bolt by supporting the counterbalance weights as you turn the bolt. Again as stated previously your altitude should be 51 degrees and this doesn't need to be changed unless you move to a different location. When you talk about lining up the polarscope on a tv aerial I assume you mean aligning your finderscope with your main scope. You don't use the altitude/ latitude bolts for this you use the locking levers and adjusting knobs near the top of the mount and leave the altitude/latitude adjustment where it is. There are several posts on doing this on the forums so do a search to explain exactly what you need to do. I apologise if I've got the wrong end of the stick but I know as a beginner how complicated it all seems when you've just got your first telescope and especially your first equatorial mount.

John

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Thanks all - I'll try removing the altitude bolts and see if the mount moves freely and report back. Hi John the adjustment I'm trying to make is for the polarscope in the mount; adjusting the three grub screws. There is an astroshed video on it where he uses a tv aerial during the day to pint at. Does anyone know what I'm talking about? :)

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Hi Frank,

Yes.

The procedure is for centering the polarscope reticule to ensure it is parallel to the RA axis... I did it on my HEQ5...

Remember to only adjust each grubscrew about 1/8th of a turn before tightening the opposing ones, or you will find the reticule can dislodge from it's recess... be very gentle when tightening the grubscrews, since the reticule is very delicate and can easily be chipped or otherwise damaged if you overtighten them.

Some people, myself included, have replaced the 3 grubscrews with some small thumbscrews, similar to those used for eyepiece locking... this makes the whole procedure a lot less fraught... the small allan key can be a real pain, even in the daytime... fortunately, it is a task that only needs doing once unless you drop the mount or dismantle it for some reason.

The alignment of the finderscope is a totally separate issue which aligns the centre of the finderscope view with that of the main telescope... this is best done on a distant object (at least 2 miles away) or on a bright star.

Let us know how you get on.

Best regards.

Sandy. :grin:

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Hi all - I don't think my last post went through. But the jist of it was that I will have a try of unlocking both altitude bolts tomorrow to see if I can produce free movement. John the alignment I want to achieve is where you align the polarscope to cope for drift using the grub screws I believe. There is an astroshed you tube video where he uses a tv aerial for this.

Cheers

Frank

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Hi

When I first got my heq5 I couldn't move it in altitude. I had to use my body weight to loosen it (with no altitude bolts screwed in). Once I'd got it moving it was ok to adjust. I didn't need to remove the latitude scale.

I can't help with the polarscope - I've never used mine! I have seen the Astronomyshed video though. It looks very fiddly! To be honest, unless you intend to do precise polar alignment using the polarscope, with a view to imaging, then it's probably best to leave it alone. If you intend to do imaging then some sort of drift alignment (which doesn't use the polarscope) is probably a better way to polar align.

Cheers

Louise

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Yeah I saw astrosheds video about using Alignmaster. Yes I do want to do imaging through the scope; webcam and dslr therefore unfortunately I have to do precise polar alignment. But I needed to check if the polarscope was properly aligned with the mount. The reason for me doing the check is two fold. One even with 3 star alignment and correct lat long and time details in the hand controls and correct balancing, when it slews it can be many degrees off target; which is ok for bright targets but not DSOs. Two when doing a long exposure I'm finding star drift after 30-35 seconds which I've been told for this mount (with correct set up) is very short. So I'm trying to eliminate the errors.

Unfortunately I don't have a permanent setup (I'm hoping this will change when we move house).

As squinting on hands and knees through my 51deg angled polar scope is not great for my arthritis (lol I'm only 40!!:( ) will Alignmaster eliminate this issue? I saw astroshed used a webcam whilst using Alignmaster which is great but I'm new to this Ascom concept. Is this connecting the scope to the laptop and taking the syscan controller out of the equation?

Thanks everyone for info so far

Frank

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Hi

There is a difference between star alignment and polar alignment. Polar alignment is aligning the mount's rotational axis so that it's parallel to that of the earth's (which passes through the north celestial pole). It can be quite confusing! PA has nothing to do with lining up various stars as per goto. Goto's can be 100% accurate but if your PA is out, stars will drift from your FOV rapidly. Even with good PA they will drift anyway because mounts have natural tracking errors since they are mechanical devices. Think of it like a traditional spring-powered watch or clock. They always lose or gain time and their accuracy also depends on temperature, wear, etc. But with good PA you can take long-exposure images up to the accuracy of your mount (maybe 60 seconds). The fact that mounts drift even with good PA is why people set up guiding systems in order to take longer exposures for imaging DSOs.

You will need to align your mount each time you use it if you can't leave it permanently set up. Alignmaster (and other stuff) depends on computer control which depends on you having a suitable cable connection between a laptop or PC and your mount. The Ascom software platform and Eqmod are commonly used to control SW mounts that have goto functionality. I believe connection to the mount is achieved via the handset which is set to PC Direct mode and using the appropriate cable. So you then use computer control rather than handset buttons. Yes, Alignmaster eliminates using the polarscope. It depends on you being able to see certain pairs of stars via your scope - one in the east (or west) and the other of the pair in the south (I believe). You adjust the mount via the altitude and azimuth bolts to correct the PA error that Alignmaster has calculated. In practice this is done by re-centering the chosen alignment stars as per Dion's video. 

Hth

Louise

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Hi Louise - yes that helps a lot. Having seen the astroshed video about Alignmaster, it makes polar alignment a lot easier. Ok so I just need to sort out the stiff bolts then get hold of a usb to rsxxx cable and install Alignmaster. Yay!

As for the bolt situation, the black altitude cover came off very easy (just a fingernail under the rim and it flipped off - not very good glue...). Underneath is a large hex bolt. I've managed to remove the front t bolt. Checked the thread and the metal, no sign of damage or bending. The rear bolt is another matter. As much as I try I can't get it off. I might take it to my local astro club or store to see if I can get it going again.

Frank

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