Chriske

Maybe so, and there are far more things I'd like to know about HST.
I did sent mails to NASA and also to ESA. We wanted to know more about all these parts screwed onto and sticking out of HST's hull.
But no one bothered to answer our mails.

My point is, when that thing hangs in our local observatory and visitors start to ask questions about HST.... well... I think it's quit silly having made a copy of HST, not knowing what we printed, not able to explain the purpose of all these objects around HST.

Didn’t want to hijack Astrofail's thread so started a new one.
His thread reminded me of a project I started ages ago.
In my case I wanted to test whether a larger obstruction in a telescope would degrade the image so badly as 'they' all say. Altough many parts were finished I had to abandon this project because at the time I started a new job, keeping me from finishing it.
And yes I did computer simulations using large obstructions in a Newt, but as always, I wanted to see with my own eyes if it would degrade so much that degradation would be seen visually.

Using that large flat, in the centre + that tertiary mirror(green), it's focuser is only at half the height of the focuser at far left.
To use that high placed(regular) focuser I need to tilt both(large flat + tertiary mirror) out of the optical path.
I mounted both focusing systems above one primary mirror. The idea behind it was to use the same primary mirror for both systems. To eliminate possible errors even more I made my own flats, and cut these three flat mirrors out of that one single sheet.

So... the only thing to do this all over again, is to look for all these parts. All of them are somewhere stored in a box gathering dust. If I only could remember what shelve....🙄
But I need to finish a few other large projects first right now...🤭

Question is how can there be eddies when there's no air...?  That's my point.

And btw you will need a third mirror.

A better approach would be simply tilting the secondary mirror at a steeper angle.
That secondary mirror will be larger also, but you don't need that third anymore.

Something like this has been done before a long time ago, If I'm correct it has been done by a guy in UK.
And if I'm correct(again) he did the same with a Cassegrain.
I do have a picture of it... some where on one of my old HD's.

Somehow I'm still puzzled , looking at the picture of the back I just finished, you'll see four big holes and a 'cover' on top of it.
Studying technical drawings of HST(and I've seen lots of them the last months), pointing at these holes with an arrow, there is marked 'Vent'.

Well, my question still is : Ventilation... in space...?????

14 hours ago, DaveL59 said:

nice work. Must admit that I find the same, print a photo on laser printer and its dull, laminate it and somehow it just pops  

That's btw the same I'm going to do with the hull of the thickest part of HST.  These 'metal panels' have all rivets. These rivets are drawn on paper. Yet again when laminated, these rivets do seem like the real thing.  My pall Michel is doing a very good job making all these drawings. He kinda 'took over' from me, making all the Inventor drawings too.
The thinnest part(the telescope-part) of HST will be covered with mylar or maybe just aluminum foil.

2 hours ago, DaveL59 said:

 print a photo on laser printer and its dull, laminate it and somehow it just pops  

Seems very real indeed after laminating.

They're not real solarpanels of course. They're just prints and laminated afterwards.
Looks ridiculously alike the real think when laminated.

Made a few alu-rings. These rings are there to reinforce even more HST's hull. 3x60cmdiameter and 2x42cm diameter.

Also prepared the Solar panel holders. Now I'm waiting for the delivery of the 'panels' itself.

All screws on the hull have been removed one by one to make chamfer in each hole. During assembly there was no time to apply these chamfers because I was to busy pressing the wooden panels against it's frame.

Thanks...🤗

Nope, no connections are made, pure modelling.

Wiring done.
Backside completely done now.

Let there be light..!😁

Today’s work, finishing HST's backside.
Well not completely finished, it need some wiring. That's what I'm busy doing right now.

The first picture is taken at an angle so the reflection of the sky made that panel looking blue.
In real the same does also occur. Sometimes we see pictures HST looking completely black, on another occasion we see HST look blue-ish/white, and sometimes we see different colours.
There too it all has to do with the position of the camera.
When it looks black we see reflection of the night-sky, Blue/white is reflection of the earth, and when difference colours are visible, we see reflection of the Shuttle's parts.

In real HST looks like this

And in orbit we see this:

or this :

Here we see reflection of the night-sky and Shuttle itself.

And this is how it's made.

A 'sheet of metal' made of wood.
This is a panel hanging at the side of HST.

Look who's talking....🤣

As is now 2.0m,  with the open lid installed it will be 2.4m high.
Total weight (now) is 15.1kg

And yes, it would be possible to add a optical system in that scope. But it would not be practical to use that scope with all these parts sticking out of it's hull..😁

But maybe, just maybe, if an optical system would be present, I could contact someone who could launch that Mini-HST into a low orbit.  That would be cool, not...??..🚀

Just kidding,
tempting...
No no, just kidding...🤗

Thanks for the kind words.
Bending these sheets is not that difficult you know. You only need to know when to stop adding water, it needs to be soaking wet bed not to wet. Adding to much, to long water the sheets fall apart. As a matter of fact it  has (about) the same composition as particle board.
In a earlier life, a long, long time ago(during course) we used to make our telescope tubes this way. These tubes were very hard, very stiff, and very cheap. Depending on the focal length and diameter of the scopes we made 1 to 3 telescope-tubes out of one single sheet. Cost for 1 sheet 6.5€ (these days).
Later on we started using trusses.

Aluminium delivery this morning, 6 meter long poles and profiles

Printed connectors.
The holes were printed a bit to small. All of them were enlarged in my lathe  just a little bit so the 30mm poles fit in perfectly, no play at  all.

In the picture above HST is not yet at full height. When finished it will be 2.41m long.
I made it all as light as possible. 12mm plywood. As seen on the picture it's weight is only 9.6kg. I expect the complete HST will weigh between 15 to  20kg.
The printed parts(grey and red) are to connect the aluminium poles with the wooden disks.
That thing is incredible stiff...

more to come...

In the past I've glued mirrors, as it was explained to us, in those days.
These days I never do. All friends's  telescopes that have odd shaped diffraction images I remove glue/silicone or whatever. 99% of the time problem solved.
All mirrors should be able to move in it's cells, be it very little.

There's no way triangular shaped stars are produced by a spider Neil.
Look for tension somewhere in the optics.

Strange, I'd think promoting a camera, you do your best to show prefect, if not your best pictures...