Strip down help!

[Dan13]

Hi everyone things have gone so smooth with the strip down and bearing repalcement but I've just come to put the dec axis back on the housing and see in the astro baby guide it mentions a clear washer on top of the brass worm gear. I don't have this at all and every single tiny piece has been boxed and labelled from the moment I took it apart. 

 

Question is, astro baby guide was wirh an old heq5 ( black) has anyone thats done there white newer counterpart found they also didn't have a clear washer? I have both red but no clear.

If it must be there and I don't have it does anyone know what type and where I can buy it please.

Many thanks 

Dan 

[DaveL59]

can't help with if it should be there or not, but looks like a 0.5mm thin nylon washer perhaps, which you may be able to source off the bay, tho if anyone does that diameter I don't know.

Hopefully someone will be along and say they don't and you'll be able to reassemble as I guess it's a fair bit of work to do it and find you really did need it and have to undo it all again.

[Dan13]

1 minute ago, DaveL59 said:

can't help with if it should be there or not, but looks like a 0.5mm thin nylon washer perhaps, which you may be able to source off the bay, tho if anyone does that diameter I don't know.

Hopefully someone will be along and say they don't and you'll be able to reassemble as I guess it's a fair bit of work to do it and find you really did need it and have to undo it all again.

Thanks dave, rother valley do them but its all greased up ready to go now! I spoke to a mate who said his didnt have one either and he cut out a mill carton and used that! 

 

Will have to order from rother Valley 

[DaveL59]

could try fashion one out of a milk bottle top, perhaps?

[Dan13]

7 minutes ago, DaveL59 said:

could try fashion one out of a milk bottle top, perhaps?

I'm going to give it a go! Can't be worse then not having one surely?! Then ill order the rother valley ones tomorrow 

[Fraunhoffer]

I've cut plastic washers for various projects from plastic milk cartons in the past. (HDPE).

[Dan13]

7 minutes ago, Fraunhoffer said:

I've cut plastic washers for various projects from plastic milk cartons in the past. (HDPE).

This is great to hear! Thank you,  just cut it now and tbh looks great! Fingers crossed 

[Dan13]

3 hours ago, Fraunhoffer said:

I've cut plastic washers for various projects from plastic milk cartons in the past. (HDPE).

Seems to work OK but having massive issues with the worm adjustment! Been at it 4 hours and about to throw the mount out the window! 

[Fraunhoffer]

Ah those cursed 5 screws. A lot of patience, cups of tea, and very very slight adjustments at a time. I see are following the astro baby guide so not much to add. 

My mount is slightly different but same process. I do up the 2 outside screws till they are just taking the slack out but could still be nudged along by the 3 adjusters. Check the worm is not tilted. Then I  do up the outside 2 adjusters and slacken the middle one until it just starts to bind the worm then adjust the middle one just a nudge to release the worm.

They are in a push-pull arrangement with the outside 2 adjusters pulling the worm into the gear and the centre one pushing it out. The outer 2 can also adjust the tilt of the worm.

Then I check the full rotation of the worm and usually find there's a tight spot somewhere, so I readjust there. The downside is that it means the place where I started now has a bit more backlash. But that's just the way it is. 

Then I do up the 2 outer screws that clamp the worm in position. At this point I usually find the worm binds again, so I have to slacken them off and tweak the centre screw in and the 2 other adjust screws out to give the worm a bit more clearance before doing up the 2 outer clamp screws again.

Tedious and very small adjustments. Sometimes it's just a nudge. The threads are small in the alloy so be careful not do things up too tight and strip threads.

You probably knew all that already, but hope it helps.

Edited July 17, 2020 by Fraunhoffer

[Dan13]

1 hour ago, Fraunhoffer said:

Ah those cursed 5 screws. A lot of patience, cups of tea, and very very slight adjustments at a time. I see are following the astro baby guide so not much to add. 

My mount is slightly different but same process. I do up the 2 outside screws till they are just taking the slack out but could still be nudged along by the 3 adjusters. Check the worm is not tilted. Then I  do up the outside 2 adjusters and slacken the middle one until it just starts to bind the worm then adjust the middle one just a nudge to release the worm.

They are in a push-pull arrangement with the outside 2 adjusters pulling the worm into the gear and the centre one pushing it out. The outer 2 can also adjust the tilt of the worm.

Then I check the full rotation of the worm and usually find there's a tight spot somewhere, so I readjust there. The downside is that it means the place where I started now has a bit more backlash. But that's just the way it is. 

Then I do up the 2 outer screws that clamp the worm in position. At this point I usually find the worm binds again, so I have to slacken them off and tweak the centre screw in and the 2 other adjust screws out to give the worm a bit more clearance before doing up the 2 outer clamp screws again.

Tedious and very small adjustments. Sometimes it's just a nudge. The threads are small in the alloy so be careful not do things up too tight and strip threads.

You probably knew all that already, but hope it helps.

Thank you, you have given me something to go on, the thing thats frustrating me is that i get it to a point where the head doesnt have any play and i can also rotate the dec head by moving the belt cog by hand, but when i move the RA head its stiff! i cant get my head round how the worm effects the RA head when you release the clutch, it doesn't make sense to me?!

[Fraunhoffer]

The RA clutch is usually a very basic device that just jams a bolt with a plastic end onto the side of the large worm pinion and carrier. The clutch lever should have a little  bit of slop when its fully off. My clutch lever engages about half way through its movement. If it's not fully off there will be some drag. The lever can be removed so that the bolt can be rotated to a good place and then the lever put on again. When lever fully off there should only be a small bit of internal bearing drag when the Ra is rotated. 

 

 

[Skipper Billy]

I don't want to upset you but the adjustments should really be made with the mount at the kind of temperature it will be used at.

I spent ages getting rid of the last vestiges of backlash in my nice warm lounge.

First nice cold night out it needed doing again as a fair amount of backlash had reappeared when everything cooled down.

 

 

[TerryMcK]

11 minutes ago, Skipper Billy said:

I don't want to upset you but the adjustments should really be made with the mount at the kind of temperature it will be used at.

I spent ages getting rid of the last vestiges of backlash in my nice warm lounge.

First nice cold night out it needed doing again as a fair amount of backlash had reappeared when everything cooled down.

 

 

Absolutely. I concur as I adjusted the backlash on my mount and first cold night it made an alarming noise. I had some long nose pliers with me and took out the rubber bungs on the side of the mount and slightly loosened the collar on the front screw with the pliers engaged in the slots - this one on the HEQ5 adjusts backlash on RA. Silence ensued and I've not had a issue since.

[Dan13]

54 minutes ago, Fraunhoffer said:

The RA clutch is usually a very basic device that just jams a bolt with a plastic end onto the side of the large worm pinion and carrier. The clutch lever should have a little  bit of slop when its fully off. My clutch lever engages about half way through its movement. If it's not fully off there will be some drag. The lever can be removed so that the bolt can be rotated to a good place and then the lever put on again. When lever fully off there should only be a small bit of internal bearing drag when the Ra is rotated. 

 

 

Hi , thanks, the clutch doesnt seem to be my issue, ive just noticed while taking it apart again that the brass square block that the bottom grub screw hits was actually off centre, also my washer was a little too big and now it runs more freely. i will attempt it again later with another clear head.

[Dan13]

28 minutes ago, Skipper Billy said:

I don't want to upset you but the adjustments should really be made with the mount at the kind of temperature it will be used at.

I spent ages getting rid of the last vestiges of backlash in my nice warm lounge.

First nice cold night out it needed doing again as a fair amount of backlash had reappeared when everything cooled down.

 

 

thanks billy, tbh its in my conservatory with both doors open and wind blowing in, dont think the temp is too my different to what it is now. i know it drops over night but i guess thats something ill have to deal with then, there no way im trying to do this for the first time in the dark  

[Skipper Billy]

3 hours ago, Dan13 said:

thanks billy, tbh its in my conservatory with both doors open and wind blowing in, dont think the temp is too my different to what it is now. i know it drops over night but i guess thats something ill have to deal with then, there no way im trying to do this for the first time in the dark  

Understood - I don't know what the weather is like where you are - here its about 15 degrees at the moment and I usually image at around zero or well below which makes a big difference. You dont have to do it in the dark - just cold! 

[Dan13]

2 hours ago, Skipper Billy said:

Understood - I don't know what the weather is like where you are - here its about 15 degrees at the moment and I usually image at around zero or well below which makes a big difference. You dont have to do it in the dark - just cold! 

No worries Billy. Its about 16, here and goes to about 12-13 through the night atm.

 

I am really really really struggling with the worm adjustments! Just said to my wife, this has to be the single most frustrating thing I've ever done! I've been going at it 2 days now!

 

I get to a point where the belt cog spins nicely and there's no rattle but there's always....always a slight bit of stiffness some where! Any advise would be greatly appreciated 

 

Dan 

[Skipper Billy]

14 hours ago, Dan13 said:

I get to a point where the belt cog spins nicely and there's no rattle but there's always....always a slight bit of stiffness some where! Any advise would be greatly appreciated 

Its because the gears are not quite round - in the end I picked the high point (the point where it is stiffest) and adjust the backlash at that point. That will leave you with a bit of backlash elsewhere but just run east heavy.

Its a compromise but short of replacing the gears there isn't much else you can do - there is no guarantee that a new set of gears would be any better - they could be worse!! Its a fact of life at the price point.

[Dan13]

31 minutes ago, Skipper Billy said:

Its because the gears are not quite round - in the end I picked the high point (the point where it is stiffest) and adjust the backlash at that point. That will leave you with a bit of backlash elsewhere but just run east heavy.

Its a compromise but short of replacing the gears there isn't much else you can do - there is no guarantee that a new set of gears would be any better - they could be worse!! Its a fact of life at the price point.

Cheers Billy. Yes I am actually contemplating upgrading the mount but still want to complete this. I'll try your advice.

Thanks 

Dan

[Skipper Billy]

2 hours ago, Dan13 said:

Cheers Billy. Yes I am actually contemplating upgrading the mount but still want to complete this. I'll try your advice.

There is a lovely secondhand Mesu on ABS 😉 

Nae pockets in shrouds etc !!

[Dan13]

43 minutes ago, Skipper Billy said:

There is a lovely secondhand Mesu on ABS 😉 

Nae pockets in shrouds etc !!

Haha, bit overkill for my rig there billy. 

 

Billy can I ask you mate , I've now put the mount back togther and slewed 360° with the RA and DEC on eqmod and everything seems fine, everything is moving and no loud crunches etc. Is there anything else I'm looking for as to a tell tell sign the worms need further adjustments? 

 

Also is there a program I can use to see if its running OK without phd and a clear night?