33 replies to this topic

[Maff]

I'm not a fan of the original focuser and I think the primary mirror could use some locking bolts to hold collimation better. However, those are just my thoughts from seeing it since I haven't built on myself (yet). Maybe I will change my mind about that after I build one. I must also say that I wouldn't use the word "wrong" since if it works there really isn't a wrong way to make a scope.

I think that's totally fair. I encourage using nyloc nuts with hex bolts, or nyloc bolts alone to secure the collimation assembly.  

The focuser is a curious result of my push for accessibility. It's crude, but a tensioning screw removes any slop.  The point is to make it as simple as possible to make and assemble -- just a big screw.  Two prints, a screw and a nut.  Dead easy.  But not perfect, just the best balance between easy to make, and easy to use.  I myself use more complicated focusers -- I just couldn't encourage project adopters to saw a steel rod, buy a bunch of bearings etc.  The remixes have all manner of crazy focusers, most of which I haven't tried. A crayford, a rack and pinion, some friction bearing stuff.  My favorite is the non-rotating screw with collet. 

 

Honestly, the community feedback and crowdsourcing on derivatives and modifications has been amazing - my own planetary images have been improved by the use of crowdsourced focuser designs. The complicated one seen here is the work of no less than four individuals working separately 

 

 

 

          

[luxo II]

Looks very steam-punk.

 

NB I like your finder, I need something like that. 

Edited by luxo II, 02 December 2022 - 06:05 AM.

[Rayje1997]

I think that's totally fair. I encourage using nyloc nuts with hex bolts, or nyloc bolts alone to secure the collimation assembly.  

The focuser is a curious result of my push for accessibility. It's crude, but a tensioning screw removes any slop.  The point is to make it as simple as possible to make and assemble -- just a big screw.  Two prints, a screw and a nut.  Dead easy.  But not perfect, just the best balance between easy to make, and easy to use.  I myself use more complicated focusers -- I just couldn't encourage project adopters to saw a steel rod, buy a bunch of bearings etc.  The remixes have all manner of crazy focusers, most of which I haven't tried. A crayford, a rack and pinion, some friction bearing stuff.  My favorite is the non-rotating screw with collet. 

 

Honestly, the community feedback and crowdsourcing on derivatives and modifications has been amazing - my own planetary images have been improved by the use of crowdsourced focuser designs. The complicated one seen here is the work of no less than four individuals working separately 

 

 

 

          

Just to be clear, I think the focuser design in genius for the reasons you listed. When I first saw it I went “huh that’s cool” then I thought about using it lol. But I’m excited to get a printer and will try it if only to have something cool to print. You have built and awesome community and I’m glad I found it.

[Leia]

Just to be clear, I think the focuser design in genius for the reasons you listed. When I first saw it I went “huh that’s cool” then I thought about using it lol. But I’m excited to get a printer and will try it if only to have something cool to print. You have built and awesome community and I’m glad I found it.

Just thinking, maybe the people who like the scope, but not the focuser could use a different focuser? I haven't made any scopes, though, and haven't checked if the design could support that, however.

[Rayje1997]

Just thinking, maybe the people who like the scope, but not the focuser could use a different focuser? I haven't made any scopes, though, and haven't checked if the design could support that, however.

While looking at the remixes page it looks like people have used different focusers. That's probably what I will do. I will build the original design and play with it and then decide my preferences. The best part about open concepts like this in combination with a 3d printer is that it allows for experimentation without spending huge amounts of money. I really hope to start an astronomy club in my area one day, and if I could build a couple of these and have a few of the different parts printed as well, then I could teach people about scopes in a way that would be prohibitively expensive otherwise. 

[petertinkerer]

Hello! I will be getting a 3d printer in the near future and it has sparked an interest in 3d printing a telescope. I saw the Hadley telescope and thought it was really cool, but I had a few issues with the design and thought I could improve on it a bit. Then I began thinking that I really wish the project itself was open source. That's when I decided that I wanted to create open source projects for education and for those who just want to make a telescope as cheaply as possible. I also thought that I would like to have refractors as well as reflectors. This is when I began looking for optics, and also where I ran into issues.

 

There is a site called Surplus Shed that sells lenses for projects and education and I was able to find a 60mm f/5 set of those that would work for such a project. I would like to find a couple more sources for lenses in the 50-80mm range as well, but my biggest issue has been finding a reputable source of small spherical newtonian mirror sets. I'm looking for something in the 114-150mm range of spherical mirrors. I figure if people really want a parabolic mirror, they can source that themselves, but for the purposes of having a really cheap project I want to keep with spherical mirrors and achromatic refractors. 

 

If anybody knows of a good source for either achromatic lenses or spherical newtonian mirror sets (primary and secondary together) I would greatly appreciate you sharing. Again, I'm looking for achromatic lenses in the 50-80mm range and spherical newtonian mirror sets in the 114-150mm range that include a secondary mirror. These need to be reliable sources that can be listed with the project so that people can build their own.

 

Thanks in advace!

 I have very similar ambitions to you  with the difference that I specialize in using a 3D printer to make binocular telescopes rather than just telescopes.  I have used vendors from Ali-Express many times for 114mm 900 mm focal length mirrors.  These are spherical mirrors and are very inexpensive (<$30 for primary and secondary) but they perform remarkably well.  I have also tried out the $60 spherical 150mm F5 which in theory should not work well at all but actually work fine up to 25-35X which makes for a wonderfully large and bright exit pupil (or pair of exit pupils in a binoscope).  I have also bought numerous inexpensive achromats from Ali-Express in the range 50 to 80mm of varying focal lengths lengths and been very satisfied with them considering the price.  I was particularly happy with a pair of 80mm diameter 600mm focal length achromats for $30 each which when built up into a binoscope I was able to see half an Io peaking out from the side of Jupiter at 90X.

 

Please check out my website petertinkerer.com, you may find a few useful leads.

 

Peter

 

The photo is an Iphone snap shot of the moon through  one eyepiece of a 114mm F8 sperical mirror binoscope.  The real image as seen by both eyes at 130X is extremely crisp and unforgettable. 

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[Rayje1997]

 I have very similar ambitions to you  with the difference that I specialize in using a 3D printer to make binocular telescopes rather than just telescopes.  I have used vendors from Ali-Express many times for 114mm 900 mm focal length mirrors.  These are spherical mirrors and are very inexpensive (<$30 for primary and secondary) but they perform remarkably well.  I have also tried out the $60 spherical 150mm F5 which in theory should not work well at all but actually work fine up to 25-35X which makes for a wonderfully large and bright exit pupil (or pair of exit pupils in a binoscope).  I have also bought numerous inexpensive achromats from Ali-Express in the range 50 to 80mm of varying focal lengths lengths and been very satisfied with them considering the price.  I was particularly happy with a pair of 80mm diameter 600mm focal length achromats for $30 each which when built up into a binoscope I was able to see half an Io peaking out from the side of Jupiter at 90X.

 

Please check out my website petertinkerer.com, you may find a few useful leads.

 

Peter

 

The photo is an Iphone snap shot of the moon through  one eyepiece of a 114mm F8 sperical mirror binoscope.  The real image as seen by both eyes at 130X is extremely crisp and unforgettable. 

I will 100% take a look at your website! I have been curious about trying out a binoscope or binoviewers for my sketching projects to make it more comfortable to look at an object for a long period. I'm not saying that these would be perfect for it, but to be able to try it out without making my wallet cry and to learn, it could be worth it. Thanks for sharing!
 

[gordtulloch]

The lesson learned could be how to make a telescope that is hard to use and quickly disappointed in.

 

Yup. My first mirror 20 odd years ago was an 8" F/10. Never got put in a telescope because of the problems with such a long focal length. Sitting waiting to be reground to F/3.

Edited by gordtulloch, 03 December 2022 - 04:41 PM.

[Rayje1997]

Yup. My first mirror 20 odd years ago was an 8" F/10. Never got put in a telescope because of the problems with such a long focal length. Sitting waiting to be reground to F/3.

Fortunately the 114mm mirrors are f8 which should be long enough to deal with most of the issues, but at only 900mm focal length meaning that it shouldn't be super hard to use