Astrotrac Wedge Mod

[focaldepth]

Hello all,

Here is another (crazy) mod from focaldepth.

In preparation for SGLX, I wanted a portable tracking mount for DSLR or Skymax and an EQ5 was outside what I wanted to spend. Having already got an Astrotrac on a Manfrotto with 2 Junior heads, I knew that was not stiff enough. So I made an adaptor to fit the heads on to my redundant EQ6 legs.

This was much stiffer but still a bit too much flex below the polar aligned point causing drift with the poor balance of the scope.

As luck would have it, there was an Astrotrac Wedge on the SGL classified section. So I bought that. (Thanks John)

The final arrangement, while not ideal, is stiff enough to track quite well.

Now then. The wedge is a nice piece of kit. However there is a slight design flaw. The ALT adjustment has a coarse setting in 15 degree increments and a fine adjustment of 15 degrees.

This is fine unless you live at a latitude of 54.5 degrees as I do. So I need to use the wedge right at the end of an adjustment range. This is do-able but annoying. (Yes, I could tilt the tripod)

So Now it is crazy mod time.

Disassemble the wedge.

The Alt adjuster.

Adjuster at the limit of movement.

Milling a 2mm clearance on one side.

Adjuster at new limit of movement.

So enjoy and copy at your own risk.

[StuartJPP]

Interesting...

Have you seen the mod for the Manfrotto 410 geared head to convert it from 3-axis to 2-axis?

It removes some weight but makes it a bit more stable apparently...also makes it a bit more compact.

[focaldepth]

No, Stuart I haven't, I'll take a look.

Althought I find the 3rd axis useful to keep the center of gravity of the scope close to the Astrotracs zenith. With a counterweight, the 2 axis mod sounds a good idea.

Thats another project to add to the list.

Thanks.

[StuartJPP]

No, Stuart I haven't, I'll take a look.

Unfortunately I have been trying to find the link but just can't...will keep looking. If you find it, post it as I should have saved it in case I wanted to modify the one I have got.

It was a simple modification (apparently) where the one axis is replaced with the other as each one is basically the same.

[focaldepth]

There is a thread, "Manfrotto 410 geared head", I'll link when near a proper keyboard.

[focaldepth]

http://stargazerslounge.com/topic/63451-manfrotto-410-geared-head/

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