Flock my focuser tube?

[Adz]

Hi all,

I am just flocking my 200p OTA. Wondered if I should do the focuser tube as well? I have a little flocking left over and it looks very shiny in there.

But does it cut out any light from the optical patch up into the eye?

Many thanks,

[Tinker1947]

I done my OTA last week, not really sure about the focuser, the fun bit is lining up the secondary mirror.

[SaraG]

Aren't commercial OTA's already blackened out inside?

How thick is the flocking material? Won't this reduce the aperture due to the decreased inner tube diameter?

[John]

My focuser drawtube is ribbed internally but not flat blackened (it's black CNC). I'm going to use flat black paint on it but not flocking material.

[SaraG]

My focuser drawtube is ribbed internally but not flat blackened (it's black CNC). I'm going to use flat black paint on it but not flocking material.

I just shined a white light up my SW focuser tube, it is blackened, and that is a cheap product lol.

It looks like dark grey matt powder type paint on it.

Hmm.. What is the absorption / reflectivity of this flocking material?

[John]

I just shined a white light up my SW focuser tube, it is blackened, and that is a cheap product lol.

For some reason Orion Optics don't actually blacken theirs. I think the argument is that ribbing has the same effect (it's like micro baffling) but while I'm blackening things I might as well do the drawtube.

[SaraG]

For some reason Orion Optics don't actually blacken theirs. I think the argument is that ribbing has the same effect (it's like micro baffling) but while I'm blackening things I might as well do the drawtube.

Or why not just replace the drawtube, just a thought.

[SaraG]

Another thing that just occurred to me, if this is a "fiber" is there any risk of lose fiber strands getting in the image?

[Adz]

Just finished up and it looks smashing!

Did the entire inside of the tube (a vast improvement) and flocked the inside of the focuser tube. Got it perfect and FLO's flocking material is so thin I can barley see it obstructing any light up the focuser tube.

Contrast should at a max now after blackening the secondary sides too

Now to start a full detailed collimation, starting with is the focuser right... I presume the little alan key fittings on the side adjust it's collimation?

Thanks,

[SaraG]

Can we see a BEFORE and AFTER resulting picture?

How about a step by step process on the "modification"

[SaraG]

Oh another thing came to mind, how does this flocking material handle heating if used with solar imaging and a Wedge?

Will it catch fire? Burn out? etc?

[John]

Or why not just replace the drawtube, just a thought.

It's an integral part of the focuser with the flat milled section on the underside. While the Orion OC1 crayfords are not the best there is, it's certainly good enough in operation for me as a visual observer. A dab of flat back paint costs far less than having a replacement made I reckon.

[Adz]

Yeah I took some pictures of that sort of thing Sara, will get another thread up whenever I can

Focuser square

Secondary in line perfectly!

....now the easy bit!

[Tim]

It wouldn't hurt, and may well help

You can also construct baffles for the focuser tube. But that's another story....

[Adz]

I barely found time/natural light for this bit of diy