Zhumell Z100 100mm f/4 Newtonian

[Alan64]

I finally got round to removing the bulk of that sooty black paint lining the optical-tube.  It was a right good finish, wonderfully flat and of a deepest black, but the interior must be glossed, then flocked...

[johninderby]

Better to get some 600micron acetate sheet to make a liner with. Then apply the flocking to the acetate shhet and slde into the tube. Makes for a very neat wrinkle free job particularily on a small OTA. 👍🏻

Pics of 10” dob with acetate liner cut to fit and then the finished job.

Edited October 4, 2019 by johninderby

[Alan64]

5 minutes ago, johninderby said:

Better to get some 600micron acetate sheet to make a liner with. Then apply the flocking to the acetate shhet and slde into the tube. Makes for a very neat wrinkle free job particularily on a small OTA. 👍🏻

I wouldn't say better; easier, rather.  Unless of course there'd be a pressing need to remove it in future.

[Alan64]

...completed.

[johninderby]

I’ve flocked a number of scopes and found by using a liner you can pretty well guarantee a perfect job. The smaller diameter the OTA the harder it is to do a neat job. You’ll find out when you start to apply the flocking. 

Edited October 4, 2019 by johninderby

[Alan64]

I had no trouble with this 70mm f/13 achromat's tube...

...nor with this focusser's drawtube...

Come again?

[Alan64]

A home-repair/replacement project reared its ugly head...

...hence a delay, but not for long.  I decided to go with a two-handle for the kitchen this time round.  Plumbing is yet another of my specialties.

The optical-tube was masked off...

...then glossed for the flocking...

I may now J-B Weld the primary-cell's mounting-hole extensions onto the tube...

[wormix]

Thank goodness - thought you had disappeared after it went quiet for a while. 

 

I like to catch up with these projects with my morning tea before starting work!

[Alan64]

I had forgotten that recesses into the cell had to be made, and for each mounting-hole extension.  Those are now done...

Now I may J-B Weld the extensions onto the tube...

[Alan64]

"Dust" of steel, to bolster the J-B Weld, and thereby the extensions to the tube...

[Alan64]

[Alan64]

[Alan64]

With stainless-steel flat-washers integrated, the screws for holding the position of the primary-cell during collimation hold fast when battened down; delightful.  However, now I don't want to use Phillips-type screws for this.  Instead, I will be heading to my local hardware for hex-key screws rather, yet similar to those.  The Phillips-type will be fine for the cowling at the front, as they will be battened down once and forgotten.

I could go ahead and flock the tube, but I really do want to wait until I get the cell sorted out.

Edited October 12, 2019 by Alan64

[Alan64]

Still doddering along I am...piddle, pitter, putter...

That's more like it.  In that the primary-mirror will be moved forward by the thickness of a toothpick, combined with limited range of the low-profile focusser, the ability to adjust the cell accordingly will be there if needed, albeit way-overkill given the effected range of adjustment.

[Alan64]

The three, new mounting-screws for the primary-cell have been cut down, and to where they just barely "peek" out past their jack-nuts...

[Alan64]

To ensure that the bronze-veneered extensions do not pop off in future. these parts are for securing same to the optical-tube in the highly-unlikely yet not-impossible event that the epoxy fails...

Note how one side of each of the nuts has been filed down, and so to clear the flange of the primary-cell.

[Alan64]

After the three screws shown above were sawn shorter, all three sets of hardware were installed...

The extensions are now completed.  Next, I will need to matte-blacken the hardware on the inside, along with other related areas.

[Alan64]

Where's the hardware now...

I think I can see the nuts; can you?

Nice 'n' dead down there...

[Alan64]

The primary-mirror has now been secured into its cell with five globs of clear-silicone, and spaced...

[Alan64]

https://www.youtube.com/watch?v=Gl6F12DWI7o

The primary-cell is completed.

[Alan64]

[Robert72]

Is anyone else as confused as I am about the post with the 5 sticks followed by the youtube clip?

[Gina]

Yes!

[Alan64]

The first section of the flocking has been installed.  This time round I wanted to straddle the tube's seam with a single piece...

[Alan64]

The second section...<cough cough cough wheeze>...has been installed...