Ampthill

I was imaging the Orion nebula last night, I noticed a line in the bottom right of the image.

The exposure time was 20 sec, with a Skywatcher 72ed.

It shows up on 9 images

Could this have been an asteroid?,  It seems too slow for a satellite!.

Any thoughts would be great!

LIGHT_20s_1000iso_+12c_20200302-19h58m34s007ms.CR2

5 minutes ago, Chriske said:

The knobs are really nice...!
If I'm mistaken these are not knurled. I think it is a milling job, correct..?

I made them on my lathe, with a vee tool set at 90 deg to normal, then scrape it down the side making a groove (5 thou at a time),

then with a pointer on one of the change gears at the back of the lathe head, move the spindle round to the next tooth and repeat. 

What you get is very nice evenly spaced grooves, Gears could be made like this too !

Ive made a better coarse knob, and re-anodised the black parts, I think it looks better now !.

20 hours ago, Stub Mandrel said:

That looks pro!

I've been looking at making a  'daisy wheel' reduction system, how does yours work? Any pics of it in pieces?

The way it works is this, Insde there is a brass barrel with three holes drilled into the side of it, three 7mm ball bearings go into these holes

,the end of the brass barrel has a 2mm hole in it, that has a piece of 2mm drill as the "fine" spindle,it has a recessed area that the bearings

 run on, the O/D of the bearings run in a hardened tapered steel barrel, The bearings are "loaded" by a brass nut that runs on 1.5mm ball bearings.

The coarse knob is fitted to the brass barrel, and the fine knob is fitted to the 2mm spindle.

This web page should give a better understanding.  http://helixgate.net/tmb1.html

I found the most difficult piece to make was the recess in the 2mm spindle, as it has to be perfectly true and round, or it will feel lumpy

in use.  Bigger bearings or smaller spindle would give a finer ratio.

  While im on the subject, Ive found a great way to make the knurlled knobs, If anyone wants details, let me know!

Here is the feather touch focuser Ive made for my cpc800, Its made from anodised aluminium,

with a hardened silver steel race for the ball bearings, Its turned out to be a 9:1 ratio, and

seems to work great!, (Also saved myself £300 !!!).

Heres My AR6 150mm