Chriske

It' s 50 years now, SaturnV, the Moon, but it's also the birth of our observatory were I live. So during open door mid September there's something to celebrate, it's in fact a double celebration.  For that occasion I'm planning to print a few scale models of that iconic SaturnV rocket.
Started to draw Saturn V a few days ago. The first stage is done and I printed a section of that first stage.
To speed up things a bit I will print that thing in SpiralVase modus. So in fact it's nothing more then a shell. To speed up things even more I'm using a 1.5mm nozzle.

My goal is to print that rocket as high as 2 meter, no gantry.
Tried printing at 60mm/s but that was a bit to fast for my 1.5mm nozzle. At layer 5 (in the picture) there kind of a rim, that suppose to be there. A bit higher up is another one , that's were I changed speed, so I need to print that again.
Instead of 1.1 hour(as my slicer said) the part in the picture took me about 1 h 25 m for this part.

Size of the part in the picture = 195mm diameter, hight of that first section(not stage) 100mm.
My guess : continuous printing,  it'll take about two days to print this rocket using that 1.5mm nozzle .
Going to print the very small and delicate parts with a smaller nozzle. The most upper thrusters(outside the LEM section, if I'm not mistaken) are VERY small indeed. If I let the 1.5mm do that thruster, well it'll be just a blob of filament imo  ...

To assemble this thing I drew and printed inside skirts. In these skirts are a few holes(close to the perimeter). During assembly I'll insert threaded rods through these holes. Every part is supported by nuts and washers. Printed as SpiralVase without that support that thing will  collapse in a minute.

Finished that second section, just to test the quality of the perimeter, and it looks very nice.

Gina,

I surely hope you took some notes because I'm going to ask you a 'question or two' about this project in a few weeks...😁
 

While assembling the scopes, drawing the fork and mount. I'll be using OnStep software.
Between these two (blue)forks the(altitude)stepper, together with worm and wormwheel, will be installed.

Busy installing these 36 ball bearings.
I should not have use these LMUU in the first place, I only wanted to use them because it is far less work to install them.
Anyway, these 'selfmade' bearings are far better, especially because I can completely rule out all play in that system.

New parts with selfmade linear bearings.
In all(36) 5mm holes sits a axis + ball bearing 5x8x2.5. All these 5mm holes are reamed to the correct size, so the axis are press-fitted in the units.

On the right the old system with these LMUU8 linear bearings and on the left the new system, with adjustable bearings. I use this system also in all my printers btw. Works perfect.

Didn’t wait until second test-setup, abandoned the LMUU linear bearings and drew new IPD blocks were every third ball bearing in each hole is adjustable. Meaning there are 12 fixed ball bearings + 6 adjustable,  in each IPD unit. No play is allowed here. Its btw the exact same setup as I use in my 3D-printers I've built so far. All 5mm axis are removable(in case of ball bearing failure. But until now, in all the 3D-printers I've used this system not one ball bearing got broke.

Anyway, this is how it looks like now.
A 9 hour print using a .7mm nozzle - 60mm/s. After that all 5mm holes needs to be reamed to have a very tight fit.
Ball bearings I'll be using : 5x8x2.5mm(x36)

Even the long 40mm tube, coming out of the big top-hole, is adjustable. I press that 40mm tube(about 125mm deep) firmly into the IPD unit until it's stuck. Then I can tilt these tubes(at the top) about 1° in all directions. That's where 3 grubscrews are needed for. And that's why the 3 hexagonal holes inside. In these 3 holes : M6 nuts.

First temporary assembly. Just to see how it will look like... All will be painted pristine white.
It all fits very nicely. One thing I've got to change I think. These LMUU linear bearings I did use for the IPD units to run on, do not work very smoothly. So I will replace that system and use my own selfmade bearings.
But I will wait to decide that, until second test-assembly when all is firmly bolted together.

As it it now, completely 'empty', its weight : 7.4 kg
So a carrying belt will not suffice imho, I'll need a chain...

Cutting the primary tubes (160x200mm).
I did use the exact same setup as I did to cut the SS secondary tubes. Only in this case I used a saw instead of  a grinding disk.

This tube was a leftover and was not cut straight then.

So I had to guide that PVC tube against a large board that was fixed at exactly 90° to the cutting direction in two directions

.

Tuning that focuser to have a smooth 'ride'.
In this order :

1- Aligning the dual speed focusing knob(hight)
2- Adjust tension on the focusing rod.
3- Adjusting tension on the gears
4- Adjust belt tension

Done, this is the left focuser. Works incredibly well. To be honest I had some doubts(just a little bit) myself when I was drawing that thing in Inventor. There are lots of parts adding friction. But to reduce it I installed as many ball bearings as possible. + also four additional units to remove possible play.

Notice the angled position of that eyepiece.

Time for the focusers to assemble.
These are the parts for the left focuser.
As  said before, it is kinda 'reversed' Crayford focuser. The complete focuser rides on a 40mm tube. So here too 5 ball bearings and one 6mm focusing-rod.
The eyepieces are inserted at an angle, that's part of the concept. Every Schief or Kutter telescope is a bit different. So every system has its eyepieces at another angle.
The uppermost(centre) part in the picture is a 2" to 1"1/4  adapter. It is kinda springloaded at both the inner and outer perimeter, so the eyepiece is always at the very centre of the optical train.

Assembling the green laserpointer.
Sits between the two primary tubes.
Laser is heated and stays at 18°C in winter.

The top layer of the largest part looks a bit weird. It is angled that's why. That is because the laser is at an angle to the primary tubes.

There's a big hole in the side of the unit. That hole is to allow the laser's wires to get through.
All electronics wiring will be hidden in the telescope's parts btw. Not one wire shall be visible.
To achieve this all parts have inside 'canals' to allow passage.

IPD adjustment unit done..!
Wiring will be done later.

Oops forgot to remove that nut and washer

Had no idea how much it all will weigh, I'm in fact a bit surprised. This is going to be a heavy bino...

This is just one wedge + secondary tube.

Thanks..!

Ready to assemble the IPD adjusting unit.

At the bottom of the unit is a 10 rev. potentiometer. Every revolution of that pot-meter is 2x1.25mm movement of the two eyepieces toward or away from each other.
Arduino Nano will do the math and make it visible on a display how far they’re separated.

Assembling has begun,

Cutting the secondary tubes to it's correct length. It all needs to be very precise. Every mm counts. A difference of just 1mm between primary and secondary mirror will throw the focal point 3mm away from its original location.
Made a temporary 'device' to do that cutting. Used a few wooden blocks (leftovers) to hold grinder and tube

After that I cut a 50mm hole sideways in that same tube.

very

Oops missed this one, sorry Gina...🤨

All parts do fit on a 200x300mm bed. Except for the primary mirror'ring'. That ring will be printed in two parts and bolted together.
holes for these bolts not present in the drawing yet.

200x300 bed

Meanwhile drawing the IPD adjusting-parts. This is how it will look like.
Integrated is a ten revolution potentiometer. While adjusting the IPD that built-in potmeter runs along with it so I can read what the value is.

My pal Marc(MDL) is busy making himself a Gregorian. Busy drawing that thing.
It'll be 250mm(10") f/24. He almost finished the optics, still only the secondary to polish.
We discussed how to proceed and decided to use as many printed parts as possible.
Ok we know, a FL that long requires a very sturdy construction. To begin with all is 'attached' to 3 aluminium poles. These poles are not 'in line' but interconnected in a shallow angled, so doing the construction should be very stiff.

This is how V1 looks like :

Maybe, just maybe there will be a very thin connecting rod(3mm or so) to support/connect that secondary ''far point" with that central pole. But before we decide to do that we need to find out what the result will be in the diffraction pattern. That circular shaped spider btw is chosen because it 'nulls out' diffraction in the image compared to a regular spider with 3 or 4 arms. Well, in fact the diffraction of that circular shaped spider is not completely gone of course. That circular shaped spider produces a residual pattern in the image, but that pattern is no longer visible because it is evenly redistributed all over the field of view, so in fact 'invisible'.

This is how the spot of that Gregorian looks like in Winspot. Rather good looking spot, In fact far better result compared to a  Dahll-Kirkham or a Newt. The black circle is the Airydisk. Field of view is 0.5°. It looks like the edge rays are not good at all, but in fact the end result is very good. The size of these patterns (at the edge) can be twice the size of the Airydisk without any problem.

Need to decide whether I'm going for a EQ or a AZ  to mount that bino. Whatever path I follow it'll be driven by OnStep software.
It'll be a wooden mount and tracking system. Don't know yet if I would leave that wood as is or finish it with my lathe. The wood as is looks very rough, but I like it this way, very much as  matter of fact. The outside looks very old and is covered with a bit of moss. The centre of the tree and branches are in good condition(no rot).
It was a old tree that had to go. Not because it was old but it was in the way of a new house planned at that spot. The owner wanted to get rid of it, and I happened to be at the right spot at the right time, lucky me.
The thickest piece is  about 150mm(6") diameter and would be a good base for that mount. It's apple, there is some walnut too.

That wood-lathe(in the background) is already working, restored it a while ago(still need a bit of paint). I found a1.1hp motor on a shelve in my workshop and bought a frequency Inverter, very handy that inverter. Cost 54€. Anyway it works very well and I can go as slow as 20 rpm and up to 2100 rpm. Had lots of fun working with that thing already.

Printing the Kutter's-wedges.
Although I use a .7mm nozzle it'll take almost 19hours to finish. This will be the first time I print a part with a printing-time that long.
The two secondary tubes should stay absolutely perfectly aligned(parallel), that's why in the first place these wedges need to be that big/strong, no play is allowed here. And second, I'll add some extra connections(not yet in the drawing) between these two tubes, just to be on the save side.

Finished cutting and grinding the oblong holes in the secondary tubes.

Looking good from the primary's position.

I'm not 100% shure here, but could it be that the ring is to thin and by screwing the O-ring to tight you accidentally introduced leaks because of bending the ring a tiny bit..?

Printing the baffles for the secondary tube.
I never use black, but for these baffles I made an exception.  The only thing to do is make the interior matt black with paint.
These baffles are printed using a 1.5mm nozzle(no not 0.15mm?) on my printer (special hotend - selfmade - Volcano-ish). Slicer is set to spiral vase, so the thickness of the baffles is just over 1.5mm.
I need about 20 of these 100mm long baffle-tubes. So doing the 2 secondary tubes are completely filled with these baffles.
I know I could have painted the interior of that tube. But these stainless steel tubes are very glossy at the inside. There's no way I could have blackened these long tubes perfectly using paint.
Anyway, because of the thickness of the used nozzle(resulting in a rough perimeter) I have lots of tiny baffles...
There's a bump in these baffles. That's no error. I drew that bump to allow passage to the wire connected to a fan that is mounted in the top of the scope. So looking into the secondary tube(through that oblong hole) there's no wiring visible. That thin wire will be installed between the tubes inner perimeter and these baffles.
There are btw 6 fans installed in that scope.