EQ5 weight load / gears.

[kon1966 (Kon)]

Guys, I have asked this question before...

I have a eq5 with synscan upgrade. The newtonian plus guidescope, rings etc weigh 10kg. I have put 10kg of counterweight and is petty well balanced. Is this too much for the mount and the motors. It does moves smoothly on both RA and DEC.

Should I also adjust the worm gear so it easy to turn by using your fingers or is a bit of tension recommended. At the moment it is set to a fairly tight meshing.

Regards
Kon

[Tandum (Robin)]

Hi Kon,
You got that filter yet ?

If it is overloaded you will hear a clicking sound from the motors as they attempt to move more than they can handle. I can't find a difinitave weight handling for the EQ5, the HEQ5 comes up instead and it is anywhere between 12 and 18 KGs, so I'd guess 8 to 14 for the EQ5.

Saying that, when you are pushing the limits, it all depends on balance. If it is balanced on all axis then there is no load as it's all offset. I run almost 18KGS on a HEQ5 and have to balance across the top of the scope between the focuser and finderscope to get it working properly plus I had an extension made for the counterweight arm. If I don't get the balance right the motor clicks and the images are stuffed.

Here's a couple of images from my overloaded mount with a cheap arsed OTA :-
http://www.iceinspace.com.au/forum/a...se.php?a=44418
http://www.iceinspace.com.au/forum/a...se.php?a=44300

I replaced the rubber O'ring bearings in the R/A gear set on the mount with proper ball bearing thrust bearings. I dunno if the EQ5 has this setup or not.

robin.

[kon1966 (Kon)]

Hi Tandum,

No filter yet but it is snail mail in the building.

I have put on ball bearings as well on both axises from a article on this forum and lithuum grease. I am saving up for a upgrade though.

What about the meshing spacing, should I adjust for a tight fit so I can turn each axis with my fingers, tighter or tight fit.

[Tandum (Robin)]

I found it needed to be looser rather than tighter. If I could turn it with my fingers with no load it worked ok with a load.

A lubrication engineer posted on cloudy nights forum a while back that lithium greese seperates over time and fails. He also said the white lithum greese was designed specifically for cars so it didn't stain clothing. He recommended teflon based greese. I have looked around and can not find teflon based greese anywhere. I have been using ball diff greese for model RC Cars, simply cos I have some on hand.

[kon1966 (Kon)]

Thanks Tandum...Will try adjusting tonight.

Guys,

since most of the weight is in the primary mirror and holder, is there a lighter primary mirror holder available. My newtonian is a GSO dob 8".
I have seen some made of wood on large dobs.

[TrevorW]

Originally Posted by Tandum

I found it needed to be looser rather than tighter. If I could turn it with my fingers with no load it worked ok with a load.

A lubrication engineer posted on cloudy nights forum a while back that lithium greese seperates over time and fails. He also said the white lithum greese was designed specifically for cars so it didn't stain clothing. He recommended teflon based greese. I have looked around and can not find teflon based greese anywhere. I have been using ball diff greese for model RC Cars, simply cos I have some on hand.

Teflon base grease may be obtained from a bicycle shop (used on chains) that's where I got mine from and used to replace my EQ5 grease.

link: http://www.deanwoods.com.au/store/prod174.htm

Presently I've loaded my EQ5 with a side by side saddle carrying a 120 f/5 SW refractor, ED80 refractor, DSLR and a 60mm finder scope balanced up with two 5 kg counter weights. It seems to me I've gone over the mounts weight limit although IMO if things are strong enough and balanced correctly there shouldn't be any excess strain on the gears and motors.