Wanted: Stray light cap for Leitz dry darkfield condenser

[ProtistAdmirer]

As it happens, I just learned that a friend of a friend recently got a 3D printer, so I can try this option out for low stakes. Interesting that the original part seems to be brass (thanks to Hobbyst for figuring that out). I wonder if the 3D printed resin material will become brittle over time. But I can try it and find out! So, um, Giorgio, would you want to update your CAD file with the dimensions so generously provided by Michael?

[MichaelG.]

I managed to pull a little more detail from my ‘profile’ photo

This shows the edge, and also the transition between the two curvatures :
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detail

46CCF349-502E-4F56-9B55-B886F7DD0073.jpeg (145.53 KiB) Viewed 4648 times

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Note: it is actually black-finished all over ... but there is cross-lighting, and I tweaked the levels.

Hope that helps
MichaelG.

[MichaelG.]

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... and here is edge detail from the ‘interior’ image :
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detail

8C15A138-98DE-4566-A0E8-314934B79DE4.jpeg (83.71 KiB) Viewed 4648 times

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MichaelG.

[patta]

Here we are
I've updated the design as per MichaelG measurements and photos; it was very similar than the Leitz illustration with the 18mm bottom opening. Small tweaks.

About making it,3D printed, cracking or other issues:
If 3D printed with normal pastic, think it won't crack (within 10 years). But I fear that under the light heat it will slowly melt and stick to the glass, maybe interfering or ruining the condenser . Should be fine for temperatures under 50 Celsius - 122 Farenheit. Give it a try.
From online services you can order it made of any heat-resistant plastic or metal*, 3D printed or CNC machined, probably still under 40$. If you order 1000 of them, will be 0.50$ each. Blackening, that's an extra.
May try for example https://app.craftcloud3d.com/


I've dumped the geometry files (.stl) and the program to generate them (.txt, open with OpenSCAD) on a google drive folder; the Thingiverse site still doesn't seem to work.
One design is full (recommended for 3D printing & machining) and the other is made as a shell 0,4mm thick( as original).
https://drive.google.com/drive/folders/ ... sp=sharing

* the original brass may be unavailable in some health-obsessed countries

[ProtistAdmirer]

Wow. THANK YOU GIORGIO!! That was a significant amount of work for you to do just to help out a fellow microbehunter! And thank you to Michael for providing the photos and dimensions of the mythical beast, and to all of y’all for the input and help. I can’t believe how you guys just made it happen and solved my problem for me. I will get it printed up and report back later on how it goes! I’m excited to see if this works.

[patta]

You're welvome, it was a good excuse to learn to use OpenSCAD! I look forward to see if the mystery plug works.

[ProtistAdmirer]

OK, the CAD-generated light cap is on order! It took me all of 5 minutes to install the SCAD viewer, download Giorgio's file, upload it to craftcloud3d.com, and place the order. I chose alumide as the material, polished and finished in black. Alumide is nylon reinforced with aluminum particles, which is supposed to be temperature-resistant to 130 degrees C / 265 degrees F, so that ought to do it. All this for only $16.34 including shipping! Turnaround time is 2-3 weeks, so I'll let you all know when I get it! Thanks again, guys. I'm excited.

[ProtistAdmirer]

Giorgio's SCAD file (L) vs. Michael's photo (R). A pretty good match, I think! If there are any small differences, I may be able to address them with sanding.

[ProtistAdmirer]

The 3D printed part came today! I know there are hundreds of you excitedly waiting to hear an update, ha ha. I’m attaching pics. I don’t know about the finish, it’s not really black, but I could paint it with a high temp flat black spray paint if I needed to. I’ll try it out tomorrow and post photos with it and without it in my dark field condenser.

[MichaelG.]

I wait with ‘bated breath

... exciting stuff !

MichaelG.

[Sabatini]

Good work.
You can show us pictures of their performance.

[patta]

Good to see it for real, hope it fits well.