How to fix an uneven tripod head?

[Ben Ritchie]

I've just purchased an Alt-Az mount (Tele-Optic Ercole) with the intent of putting it on an EQ6 tripod. The base looks like this

where the protruding section is 60mm across and 5mm deep. This looks a pretty good match for the EQ6 tripod head

the indented section is a bit more than 60mm across, but the mounting bolt should hold them tightly in place. However ... SkyWatcher didn't actually make the tripod plate flat and even when fastened tightly to the tripod the Alt-Az mount can still rock backwards and forwards on one axis a bit.

So ... any bright ideas about how to get the mount head solidly mounted to an uneven mount head welcome before I start experimenting? Safe to assume I have very little DIY ability

[Bizibilder]

Try three pieces of thin aluminium at 120° to each other between the tripod and the base of the head. By thin I mean 0.5 - 1mm thick. Maybe a drinks can cut up and the pieces folded will do the trick if you have no thin ali. (To see if a drinks can is Ali hold a magnet to it - if not magnetic (ie not steel) it is almost certainly ali.

[Ben Ritchie]

I've tried thin aluminium shims which help, but i'm going to be removing the mount head from the tripod for storage so would like something a bit more durable than that - otherwise I lose the shims when I take everything apart.

Part of the problem I think is that the tripod head is drilled and tapped for the M12 (?) bolt used by the EQ6 mount head, so you first screw the mounting bolt to the tripod head and then to the mount head - this means when that mount head is attached to the tripod the mounting bolt is rigidly attached to both the tripod and the mount itself. The Tele-Optic Ercole takes a M10 bolt, not M12, so in this case the mounting bolt is only attached to the mount head, it is narrower than the threaded hole in the base of the tripod head. So the only thing holding the Ercole to the tripod is the 'pull' (is that the right term?) of the bolt as it is tightened. That would be fine if the tripod head was actually a flat surface so the Ercole couldn't rock, but it isn't...

[Bizibilder]

Short of machining the head flat (you may find an engineering firm that will do the job, but at a price) maybe araldite the shims in place? At least you won't loose them when you disassemble the parts.

[Psychobilly]

You could polish it flat using gradually finer sheets of wet on a piece of glass of polished tile..

Use plenty of lube and a figure of eight motion... white spirit works well with aluminium...

The glass can be supported on a pile of wet newspaper.. which will help hold it in place..

Peter...

Sent from my GT-P7300 using Tapatalk HD

[1parsec]

Hi,

You could dremel out the areas in red to leave the 3 areas in blue which would be high pads 120 degrees apart - the 'milk maids stool' .

You'll hopefully only have to grind 1mm or so as the casting should be too far off.

Or you could place 3 washers in the recess if grinding wasn't an option.

Dave.

[1parsec]

You'll hopefully only have to grind 1mm or so as the casting should be too far off.

as the casting should not be too far off.

[steppenwolf]

Part of the problem I think is that the tripod head is drilled and tapped for the M12 (?) bolt used by the EQ6 mount head, so you first screw the mounting bolt to the tripod head and then to the mount head - this means when that mount head is attached to the tripod the mounting bolt is rigidly attached to both the tripod and the mount itself.

The thread in the tripod head only serves as a 'retainer' to stop the bolt falling out with the mount removed - it takes to part in proceedings with the mount in place so sadly, this isn't the problem.

Sent from my iPhone from somewhere dark .....

[StevieDvd]

Unless I'm missing something you have not clearly stated where the tripod is uneven. Is it the inner recess that is not deep enough or uneven, leaving a gap around the outer part? Or have you eliminated that and found the outer part of the tripod is uneven?

For either cause perhaps you could get a cheap mouse mat and make a washer out of that, one that perhaps has a hard upper surface and a foam undersurface.

You could even contact the maker/seller of the mount to see if they have seen and resolved the problem.