Possible improvements to NEQ6 mounting on pier and PA adjustments.

[Gina]

My EQ3-2 has a similar gouge, but even worse. I thought I had some photos somewhere, but I can't find them at the moment.

James

Maybe you've done more PA than me - my mount has spent most of it's life on the pier.

[JamesF]

I have to align every time I use the mount at the moment, but even when I got it my EQ3-2 was fairly old and I think it's been well-used

James

[Gina]

I checked the alignment of the gouged hole with the threaded hole in the body and found it didn't line up. I was able to see the linre-up by shining a light into the cavity through a gap in the casting. I also found the bolt was slightly bent but not enough to stop me getting it out, though a bit tight at the bend. I checked the bent bolt in the other side and found the bend was well outside of the casting so I can simply swap the bolts over and reuse them. I think with the modification, the original bolts will be alright.

As a result I didn't use the hollow as a guide but assembled the mount, set up the altitude and then used a drill bit a bit smaller than the threaded hole with some tape wrapped round to fit the threads without damaging them and carefully drilled into the aluminium lug in the right place. I then used a bigger drill bit to open up the hole to larger than the end of the adjustment bolt - to allow for adjustment of the altitude. I found the aluminium casting very easy to drill so it's no wonder the bolt end can make a hole in it. Also, the bolts must be very soft to bend like that with just hand tightening!

Here are a couple of photos. The second one shows the hole viewed in the direction of the bolt.

[JamesF]

Photos missing, Gina?

James

[Gina]

Had a glitch - fixed now plus a small edit

[JamesF]

I think that should help. Shame the bolts are bent already

James

[Tinker1947]

I think once the centre of the bolt pressing on the casting is found, i would drill a hole and thread the hole then insert some studding, the end of the studding having a indent for the bolt to push into the end that comes out the other side a lock nut to stop the stud from moving, i would think ½" or 12mm studding would do. and replace the bolt with a high tensile type with a Allen Key head for adjustment....

[JamesF]

I think once the centre of the bolt pressing on the casting is found, i would drill a hole and thread the hole then insert some studding, the end of the studding having a indent for the bolt to push into the end that comes out the other side a lock nut to stop the stud from moving, i would think ½" or 12mm studding would do. and replace the bolt with a high tensile type with a Allen Key head for adjustment....

The other alt bolt bears on the lock-nut side, at a different angle.

James

[r3i]

... but the real improvement will be from having the grub screws just tight enough and not screwed in by King-Kong!!

This is definitely a simple but very effective way of making the altitude adjustments easier to perform, particularly if you replace the grub screws with M5*20 socket cap bolts or similar (as shown in the one of the posts you referred to earlier). This allows you to ease off the pressure plate during adjustment then tighten up again after.

[Tinker1947]

Gina while you have it stripped can you get the thread size and length are the bendy bolt i may invest in replacements............

[Gina]

Gina while you have it stripped can you get the thread size and length are the bendy bolt i may invest in replacements............

M10 x 95mm

[Gina]

This is definitely a simple but very effective way of making the altitude adjustments easier to perform, particularly if you replace the grub screws with M5*20 socket cap bolts or similar (as shown in the one of the posts you referred to earlier). This allows you to ease off the pressure plate during adjustment then tighten up again after.

Yes, I thought of doing this Or I could just leave the grub screws and use the 2.5mm allen key though I think I may already have some M5x20 socket head bolts. I agree that freeing off a bit to adjust then tightening up when done does seem the way to go

[Gina]

I think once the centre of the bolt pressing on the casting is found, i would drill a hole and thread the hole then insert some studding, the end of the studding having a indent for the bolt to push into the end that comes out the other side a lock nut to stop the stud from moving, i would think ½" or 12mm studding would do. and replace the bolt with a high tensile type with a Allen Key head for adjustment....

I don't really think this extra complication is needed but thanks for the suggestion

[Gina]

I think that should help. Shame the bolts are bent already

James

Only the original "up" bolt is bent - the "down" or locking bolt is still straight Also, as I said above the bend in the "up" bolt is only slight and when used as the down/lock bolt, the bend is outside the casting and no problem.

[r3i]

Yes, I thought of doing this Or I could just leave the grub screws and use the 2.5mm allen key though I think I may already have some M5x20 socket head bolts. I agree that freeing off a bit to adjust then tightening up when done does seem the way to go

Whether you stick with the grub screws or replace with something else just boils down to aesthetics, in how you want that part of the mount to look. When you removed the cover with the latitude scale, did you manage to keep it intact or did it shatter into pieces? Some folks are lucky others aren't when removing it. Mine was a bit worse for wear by the time I'd prised it off so I replaced it with a bit of cheap and cheerful laminated cardboard and had the socket head bolts poking through. Others like Kev have made some very professional looking replacements.

[Tinker1947]

Used these people for the High Tensile Bolts 2 X 10mm @100mm and 3 X 5mm @ 20mm order didn't meet the £5 minimum so made it up with some Washers, Total cost with VAT and Postage £10.20

http://www.a2a4.com/acatalog/M10_SOCKET_CAPS_A4___80_CLASS.html

[Gina]

I got the covers off almost intact, just leaving a few small pieces round the edge on the mount. They could be glued back on with just a few cracks showing. Whether it's worth bothering I'm not sure. I think if I put the cover with the lattitude scale back on I think I'll drill 3 holes to access the grub screws or for M5 bolts.

[JamesF]

I guess once you have the holes you can do the bolt replacement at your leisure.

James

[r3i]

I got the covers off almost intact, just leaving a few small pieces round the edge on the mount. They could be glued back on with just a few cracks showing. Whether it's worth bothering I'm not sure. I think if I put the cover with the lattitude scale back on I think I'll drill 3 holes to access the grub screws or for M5 bolts.

Here's another example from the Cloudy Nights forum: http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/5109751/Main/#5108077

[Tinker1947]

I got the covers off almost intact, just leaving a few small pieces round the edge on the mount. They could be glued back on with just a few cracks showing. Whether it's worth bothering I'm not sure. I think if I put the cover with the lattitude scale back on I think I'll drill 3 holes to access the grub screws or for M5 bolts.

There are these might look nice poking out of the cover,,,,,,,

http://www.a2a4.com/acatalog/M5_KNURLER_THUMB_SCREWS_H_T_464-1.html

[Gina]

Here's another example from the Cloudy Nights forum: http://www.cloudynig...1/Main/#5108077

Thank you That looks a good option for those who move their mounts about a lot. Fortuantely mine doesn't - it stays on it's pier and only moves as far as indoors for engineering works

[Gina]

Humped the mount back into the obsy this morning but nut yet onto the pier.

I've been looking at the geometry of the altitude PA adjustment. At a guess I would say the distance from axis of adjuster bolt to axis of pivot bolt is about 40mm. Thread pitch is 1.5mm so 360 degrees of adjuster is 1.5mm at 40mm. So the altitude angle A is given by tan A = 1.5/40 = 0.0375. That's just over 2 degrees. So each degree of altitude corresponds to about 180 degrees turn of the adjuster screw. So we now have a much better idea of how much to turn the adjuster than just try-it-and-see

[Gina]

Just checked the azimuth adjustment as well (for completeness). Centre to post = 43mm. Which gives 2 degrees virtually exactly, per turn of the az knobs. So again, 180 degrees per degree of adjustment. If dials were attached to the adjustment bolts you could get pretty close after the first measurement Of course, with stepper motors, timing belts and pulleys you could pretty much automate the job

NO I'm not going that far.

[RogerTheDodger]

This looks like a good place for knobs and levers http://www.boneham.co.uk/shop/product/adjustable_clamping_lever_erm_stainless_steel

[Gina]

This looks like a good place for knobs and levers http://www.boneham.c...stainless_steel

Thanks Roger