PST filter mod for Atik 314L+

[JamesF]

In my previous posting about the mod I've done for my PST to move the BF5 closer to the sensor of my ASI120 I had an idea about doing the same for my Atik 314L+.  I know mallorcasaint uses his for imaging with a PST and whilst it is somewhat slower downloading images, it does have the advantage of being able to get the entire disc on a single frame which I can't do any other way at the moment.

So, despite not having tested the existing mod yet I felt the need to play with the lathe some more this weekend and produced this:

Basically it's a T2 to 1.25" adaptor with a an internal recess to take the BF5 unit.  It's the first time I've cut a male thread with a thread-cutting tool and I have to say it was far from easy.  Female threads (such as that I turned in the barrel part so the inside isn't smooth to reduce reflections) I don't seem to have a major issue with, but this one took ages to do and whilst it works, I reckon it could be far better.

The BF5 unit just pushes into the back:

And then the whole thing screws into the camera:

I made the T2 thread long enough that it will also work with the ASI120

Now I'm going to have to get into this anodising lark, clearly.

James

[DIYASTRO]

James, Nice one! Always a challenge when beginning thread cutting! Some types of aluminium are not too kind when attempting this but you have a thread that works which is good.

I too have to think about anodising, lots of bare shiny ali plates and bits to get blackened and protected. Need to look through some of the threads on here to find out how others are doing it.

Don't know much about PST mods either! have to find some time to follow some of these interesting projects.

Boyd

[Gina]

I'm about to try thread cutting in aluminium for my triple imaging rig   I have already done anodising but that was quite some time back and I'll have to look up what I did.  There's a thread on here about it.

Edit...  Found it - link here

[JamesF]

Aluminium is at least relatively soft for cutting threads in.  Short ones I've done just by turning the chuck by hand, but I'm going to make a mandrel and handle to fit in the back of the spindle to make that easier.  I think I need to check the cutting height for the external thread-cutting tool.  At the moment that's the only thing I can think of that might not have been right.

James

[Gina]

I've ordered some aluminium tube from ebay to use for making T2 42mm adapters - 47.6mm OD and 6.4mm wall thickness - link here   This provides about 3mm wall thickness when turned to 42mm inside one end and outside the other end.  In my case 1mm pitch internal for Pentaz/Praktica thread lenses and T2 0.75mm external for CCD cameras.  Several days delivery time so I might play with cuttung threads in ABS plastic.