Sky-Watcher 200p - collimation hex keys

[stevelup]

Hi Folks,

I got a second hand 200p at the weekend which needs collimating. Was wondering if anyone can tell me the hex key sizes needed. Are they metric or imperial?

Thanks,

Steve

[Rob_UK_SE]

On 24/08/2020 at 09:43, stevelup said:

Hi Folks,

I got a second hand 200p at the weekend which needs collimating. Was wondering if anyone can tell me the hex key sizes needed. Are they metric or imperial?

Thanks,

Steve

I believe that the threads are a metric size - M4 specifically. The Allen key required would, I assume, be a metric size too. A lot of people prefer to remove the ones supplied by Sky Watcher and replace them with a thumbscrew alternative. This means you can adjust the secondary mirror by hand, rather than requiring an Allen key... which you certainly don’t want to drop on the primary!

here’s a link to a replacement thumbscrew set: https://www.365astronomy.com/set-of-m4-thumbscrews-for-secondary-mirror-collimation-45mm-long-set-of-3-screws.html

Edited September 1, 2020 by Rob_UK_SE

[discardedastro]

Metric M4 sounds familiar to me - the central screw is a PZ2 I believe. I'll give thumbscrews a big thumbs-up - well worth swapping, it makes collimation much less fiddly and entirely removes the fear caused by waving a hex driver anywhere near the glass. I used Bob's Knobs from FLO.

[stevelup]

Thanks folks. Apologies for not acknowledging these replies - I didn't get a notification for some reason!

Great idea replacing these with thumbscrews - I'll look into that.

[wookie1965]

Just check the length of the three collimation screws I have a feeling 20mm thumb screws will work but just measure first may need 25mm. 

[stevelup]

Many thanks!