Flocking a Synta 70mm f/13 Achromat

[Alan64]

I had gone out under the Moon recently; sober, thank you; sought out its advice, I did.  I raised my hands so and asked fair Luna, "Shall I, or shan't I?  Should I, or shouldn't I?"  "Yes", she mused.  "By all means possible, and then to gaze upon my terrible countenance..."

"...yet unobstructedly.  I insist", she added.

"I shall then!", I cried, "...in memoriam..."

"...!"

<flip>

[Knighty2112]

I did flock an ST120 ‘frac I owned a while back. Whilst I like to believe it did make a difference in the views I saw afterwards, in reality the effect was minimal and more than likely just psychological. For bigger scopes with larger light grasps (Newts and Dobs) it may be worth doing, but in all honesty for smaller scopes you really won’t see much difference, unless light really does bounce around off any shiny surfaces inside your tube!  

[Alan64]

Yes, it's a bit shiny, hence the flocking...

In addition, the factory paint is greyish, "Synta-grey" I call it.  I want it black inside, and dead to all light and its reflections, no matter how subtle.  I could have simply sprayed it with ultra-flat black, but the flocking was nonetheless blacker than that, noticeably. 

There are several materials used for flocking, but the degrees of blackness varies among them.  I'm using "Protostar" flocking.  What did you use on yours?   

[Knighty2112]

14 minutes ago, Alan64 said:

Yes, it's a bit shiny, hence the flocking...

In addition, the factory paint is greyish, "Synta-grey" I call it.  I want it black inside, and dead to all light and its reflections, no matter how subtle.  I could have simply sprayed it with ultra-flat black, but the flocking was nonetheless blacker than that, noticeably.    

That is a tad shiny, yes! Hope the views of Luna give better results!  

[Alan64]

Have a look at this...

...and that of my 150mm f/5 Newtonian, another Synta product.

Incidentally, the Synta telescopes that utilise mirrors, whether a Newtonian or other, are the ones in direst need of blackening and flocking.  

[Knighty2112]

1 hour ago, Alan64 said:

Have a look at this...

...and that of my 150mm f/5 Newtonian, another Synta product.

Incidentally, the Synta telescopes that utilise mirrors, whether a Newtonian or other, are the ones in direst need of blackening and flocking.  

Without any internal baffles that light sure does bonce off the paint! Can’t remember my ST120 been as bad as that before I flocked it? At least in your case that will definitely improve things for viewing. 

[Alan64]

The flocking definitely helped with that Newtonian, as the Moon was tinted before, and by that deplorable excuse for a paint-job...

...and after...

However, Synta is aware that its Newtonians will be improved upon by their prospective owners, by some at least, therefore they are, not surprisingly, delivered barest-bones.  The rest are either unable to effect the improvement, or they do not have the time or inclination to do so, or they are oblivious to the detriment.

In the case of this achromat...

...it's a bit reddish there, but after the flocking, along with the rest I've done to it, I will be assured that it will throw up the sharpest images, the best contrast, and neutrality of colour possible.  I will then know that I can do no more to it, whatsoever, save a re-figuring of the doublet, and that's not going to happen.  

Oh, I forgot: my tool for flocking both sides of the lone baffle within...

The disc had to be notched for installing the flocking on the side facing the focusser, to bypass the tube-plugs where the dovetail-bar was once attached; along with the flocking itself, but not cut all the way across.  You can just see the clear, double-sided tape, which held the flocking in place as it was inserted.

[Alan64]

Going to town in a while to get some wooden dowels to aid in installing the strips of flocking, and...

I had run a duster through the tube a day or two ago.  Just look at what has taken up residence since...

I have the open tube on the mount, above the floor; a bit bizarre.  Perhaps some mosquitoes will fly through it.

[Stub Mandrel]

I made a t-mount to 1.25" adaptor from aluminium. I tried it out and it was a disaster, painted the inside black and it was fine.

Never underestimate the potential for one bright star to cause reflections.

[Alan64]

Almost done with the short run of this side of the baffle...

Gracious, would you look at that.

The long run however...to quote Professor Higgins whilst speaking to Colonel Pickering, "Pickering, this is going to be ghastly!", and as he put his head in his hands.

[Alan64]

After a mishap, and where I had to remove a laid strip, actually a stuck one, the flocking of the objective side of the lone baffle, and the most important side, is now complete...

[Gina]

Quite a difference ??

[Alan64]

Thank you, Ms. Gina.  I'll be starting on the long run in just a few.  I've been taking my time, as you really can't rush a job like this working with so small a diameter of a tube.  It's almost like working in miniature.

It's interesting that these 70mm refractors became available only when the Chinese took over the manufacturing of the small-refractor class.  The mount that came with this telescope is an EQ-1, and is really much too small to carry the telescope properly.  Instead, I'm going to mount this Japanese-made Towa 50mm f/12 achromat, my "Floating Achromat" I call it, on the mount instead...

I've got the wee 9V-battery motor-drive for the mount, and a hybrid-diagonal for the telescope.  But that diminutive achromat will need a good going through as well.  When it arrived, the two elements of the doublet were flipped, but nothing I can't correct.  I haven't even observed through it yet.  I am told that when looking at the Moon through it, the Moon will appear as an "etched marble".

[Alan64]

The long run; such a long and lonely "road"...

[Stub Mandrel]

I've had some success (on shorter runs) by rolling up the flock, peeling a strip along the long edge and feeding it into the tube. Along dowel or similar presses the peeled edge into place, then wangle the backing off inside the tube (it can be done with a stick and perseverance) a bit at a time, smoothing the flock down as you go.

You could even tape the backing to a dowel and wind it off the flock and onto the dowel if the tube is really long and awkward.

[Alan64]

Thank you for the suggestions, but I'd be afraid that it would buckle up in my case, and since I've never done it that way before.  I'd have to practice.  I'm already used to applying it in strips.

I have two screw-tips with nuts that I'll to have cut holes for, and that will require a strip...

I had to blacken those, and that was a chore and a half...

I've been installing the strips with a wooden dowel, with a piece of double-sided tape applied to the dowel.  I then press and stick the flocked side of the strips onto the dowel, peel the backing off the strip, then guide them into place within the tube...

That image was taken when I first started, and with a 2" wide strip, but then I removed it and reduced the width to 1", and for easier handling.  The methods suggested are similar to the instructions that were included with the flocking, but then it is also stated that longitudinal cuts are required for expansion.  With the narrow strips, the cuts will already be there; although it's not really that critical for such a small diameter, I wouldn't think.  But I'm doing it anyway, for its own sake if for nothing else.  I'll need to manage seeing down far enough into the tube to butt the strips against each other as I go along.  The long run is not too terribly much deeper than the short.  I'm actually quite comfortable when working at a miniature level like this.  I made this entirely from scratch back in the 1990s, when I lived in Memphis...  

...a lady's dressing table, of mahogany and a blond wood(not satinwood, regrettably), and inspired by those found within the first-class compartments aboard the R.M.S.Titanic .   

My eyes were a bit better then.  I haven't made anything like that since, however.  During that time, I made about fourteen miniature items, and sold most of them, including that one.  I then became employed in the public sector, and that was the end of that.  I'm now back at home, and as my mother's caregiver, so I could resume that type of work.  But, what I'm doing now, with these telescopes, is much easier by comparison, as well being connected to astronomy which has always been my favourite pasttime.  So much so that I look upon astronomy as something of a duty, rather than just a hobby.

[Stub Mandrel]

Miniature woodworking always impressed me, I struggle at 1" to the foot!

[Alan64]

This was my second salable one: a lion's-head armoire, of cherry, limba and Carpathian-elm burl.  The center door revolved revealing a mirror.  The legs were of lion's paws.  I made a set of coat-hangers for it as well.  That one came straight out of my head.  Only the door hinges were bought for it, as I never got into making those...

A neighbour next door gave me her empty compacts on occasion, and for their glass-mirrors.  The mirrors were quite large, as she preferred such, and the ideal thickness; perfect for my purposes.

During that time I made one telescope, a brass refractor on an ornate pedestal, with animal paws I carved of brass.  It took me three days to make, and it sold in three days after I took it to the shop.  A lady from Texas had breezed through, and I never saw it again.  I didn't take a snap of it either.  Back then, digital cameras weren't available, at my price-point anyway.  These images you're seeing were originally taken with what I call a "paper camera", and my elder brother's.  I've never owned one myself, only the digital type.  When I got my first digital, a 1.3MP, the taking of photographs at last became appealing to me; no trips to the drugstore, and another to retrieve them, no dark rooms, none of that.  My father had done the dark-room thing back in the '60s.

[Stub Mandrel]

7 hours ago, Alan64 said:

This was my second salable one: a lion's-head armoire, of cherry, limba and Carpathian-elm burl. 

>Boggle<

That's fantastic craftsmanship.

[Alan64]

Thank you.  I made those with only a Dremel tool, rulers and razor blades.  I now have a mini table-saw, a mini drill-press, a Foredom® jeweller's rotary tool, and all sorts of bits and pieces.  I started on this a couple of years ago: an analogue turntable in satinwood veneer over a mahogany core, and with a frosted acrylic platter.  The tonearm is of carbon-fibre, and is fully mobile.  The tonearm can be moved over and lowered onto a vinyl, and back again.

It's incomplete, as you can see, a work in progress, and part of a system, a simple one, with only a tube-amplifier and two speakers in addition.  My full-size phonograph there was made in a small town in either the Czech republic or Slovakia.  I prefer analogue to digital, musically.  

[Gina]

I like analogue for my music too

[Stub Mandrel]

I can't wait to see how you fit the diamond on the stylus ?

[Alan64]

I do have a 1 or 2-point diamond, but I also have white-sapphires about the same size; sapphires and rubies, too, which have also been used as stylii.  The stone would be set into the headshell that I haven't made yet, and visible from the top as well.  Of course, the stone will not be to scale, but you can't have it all that way.  It wouldn't be visible at all if it was to scale, and it would be the main feature of the turntable.

Oh, and the spindle of the platter will be of polished and lacquered sterling-silver.

[Alan64]

Back to the grind...

I had to determine where to cut the holes for the screw-tips and nuts inside the long run.  The method I used was pitifully simple: a sliding closed cable-tie on a long dowel, and similar to the manner in which I had determined the diameter of the baffle's hole...

The test-fitting is good, but I haven't laid it in place yet.  You might just see the hardware jutting up through the flocking there in the background...

The flocking must be set back from the edge of the long-run's opening, as shown here, and to accommodate the focusser's flange when that's inserted.  Beforehand, I will paint just forward of the flocking's edge, up to that hole perhaps, with the ultra-flat black, as there will be a narrow gap between the edges of the strips and said flange...

 

[Alan64]