Chriske

I think you should try a combination of wood and this focuser. I used printed wheels and O-rings to do the friction on that printed eyepiece-barrel. If you have no lathe, printers or other machines at your disposal you could make the main body out of wood. The rubber wheels, you can cannibalise them from old copier(zerox) or printers. You also could make a Crayford. The ball bearings can be replaced by small, thin strips of teflon. In both cases you could use a PVC pipe as eyepiece-barrel. So many possibilities, I'd ask Mr Google, just type 'Wooden focusers' or 'Homemade focusers'. Tons of homemade stuff.

Beside the printed parts you need a aluminium barrel. It has no plane, there's no need to. The diameter of the barrel needs to be precise. Also a few 6x10x2.5mm ball bearings, and an axis that fits inside the bell bearings. If you do not use the dual speed device, you need to redraw just a little bit. The big hole on the right side must be made smaller to allow a ball bearing That big hole on the right side is in fact to make room for that dual speed device. Pressure on the alu barrel is done with a very small bolt at the left(front)

Your life will never be the same again...😁

Just do it...!!!😁

ipt files OK..?(Autodesk Inventor)

I'm busy doing exactly the same, together with my son. Also a Darkstar 12" f/6. Think we're going to dump the tube and the(to) heavy Dob and make a truss instead.

Of course there's a gap now. After tensioning the springs you need to adjust the Z-homing screw.

Maybe the springs are not strong enough for the task. You might try this : Tighten all screws to close the springs completely - do not overdo-. 'Relax' the springs by turning all knobs one revolution(loosening). Now you have maximum force on the bed. Then level the bed again by only loosening the knobs.

Me too.. My beds are spring-loaded at four corners.

Meanwhile all external HST's parts, that needs to be printed, are drawn. Most of them by Michel, he just started learning 3D drawing btw. He becomes rather good at it. One of these days, when weather allows it, I'll start building HST's outer perimeters.The hardboard panels needs to be soaking wet to bend over a plastic(or other) tube.

Frustrated...? How so..?

That's what he's planning to do with that 300mm 'beast'. Astrophotography..! We need to make a very sturdy mount for that thing. He'll probably be using a Box-mount.

As a matter of fact, my son just started grinding his own optics. So that makes him old fashion too...?😁 Just kidding, I'm very glad he did, he's almost 40...

I do have very good ear buds btw...BOSE...😁

So Andrew, I'm just been nostalgic or old fashion...??😉

Well about these questions... A few days ago I was busy restoring (and recovering optics out of) a few telescopes. Reason : Got a phone-call from another member of our local observatory. He told me been busy cleaning/making room in one of our lumber rooms. His plan was to dump a few telescopes(literal : throwing away) One of these scopes was a 300mm Dob. It is a very good scope. Bought in the '80 from DarkStar (UK) Another four 250 mm Dobs aren't used anymore. One 200mm + a few other smaller scopes. Amongst them a 70mm Maksutov. Mind-boggling decision not..?..😳 Asking questions our manager told me that our youngsters don't seem to enjoy observing anymore. Lots of these younger members are 'stuck' behind their laptop he added. 40 years ago a 300mm telescope, to us it was a un-reachable goal..! Way to expensive in those days..!

Are our youngsters less interested using real telescopes these days...? ...or is there a new generation 'laptop amateur astronomers' in the making..? I need to explain a thing or two about these questions, but I wonder how many youngsters are still at it, not just building, but also observing the night sky.

One of the 'parts' hanging around HST is this little guy. Not top quality, but that has all to do with the speed I'm printing(100+mm/s) Need to paint the helmet 'glossy-gold'. Actually there will be a few of these 'astronauts' holding on to the metal handles. I wonder, do they always grab the handles to 'float' from one point to another or are they secured by a 'rope'..? I might add a cordless drill or a hammer to put in their hands(or a hacksaw...😁)

Awesome project..!! I'm drooling here...

The manager of our observatory asked me to make an even bigger SaturnV rocket. This next (last?) one will be 3.6meter high, Crawler and launching platform included. Adding the umbilical tower on the launching platform the complete structure will be almost 4 meter high. For this job I need to build a bigger printer first. Deadline mid-Sept 2020. Some smaller parts I'm already printing now, like the Caterpillar shoes for the Crawler. I need about 450(!) of these.

This is what we have drawn so far, more to come. Need to decide now what colour to use for these printed parts(pale blue in the drawing).

Meanwhile another member of our observatory (Michel) joined me drawing HST parts. I'm very happy with him helping me of course. We already did lots of preliminary drawing.

Nice looking indeed and nicely done too.. But there are far simpler startrackers that can be printed. Two printed arms, a hinge, a threaded rod and a stepper. That hinge is the polar axis.

The 'tube' of this scope will be made out of 18mm plywood. The odd shaped side-panels will be made with a Maslow. These panels will be made very accurately. I expect their shape will be well within a millimetre correct. So when the mirror cells are all mounted in the tube, the mirrors to be almost at the correct location, requiring only a minimum of collimation.

Thanks to you all for the support and the kind words..😉