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Pfocus A | a 3D printable DIY single focus solution

Creation quality: 5.0/5 (2 votes)
Evaluation of members on the printability, utility, level of detail, etc.

3D model description

The Pfocus A is a DIY single focus solution based on a Zunow WCX-80 (or Fujinon WCV-82SC) wide-angle converter.
While this has some downsides like soft edges, CA and a widening effect, it also has some benefits like low weight, multiple mounting options, a good wide-angle coverage as well as a short close focus distance. You can find comparative tech specs here:
The widening effect can also be considered as a benefit: Pfocus A can deliver an image which is actually wider than what a scope might be able to cover on its own (in other words, wider than what the Rapido FVD-35a could deliver with the same scope).

A general overview about Pfocus units and its history can be found on my website:

I understand that charging money for these files is a sudden let down for many, but please also understand the countless hours, test prints, WA evaluations etc that do take a toll on me, not only of my spare time but also financially; I don't even expect to get even with the costs I put into these projects by selling the plans. But it would be cool if it could finance me a Pizza or two.
If you already made the Pfocus before, you can still benefit from the features this housing offers as the glass is compatible.

* Pfocus A can be calibrated for properly hitting infinity focus and features markings in either imperial or metric
* improved mechanics deliver a much better focus-experience
* a rudimentary dirt-preventation will help leaving your competition in the dust, but not your Pfocus
* rich hard-stops for infinity and close focus
* you can use two different wide-angle adapters with this housing: the Zunow WCX-80 as well as the good ol' Fujinon WCV-82SC (Fujinon will need some parts printed differently, which is explained in the manual)
* focus gears are sperate from the helicoid and light path, now you can use a dope contrast colour fitting your setup!

The Zunow WCX-80 can still be purchased today but is horribly expensive when bought new; however, getting good deals on them is not as hard as it seems. Optically, it's a tad worse than the Fujinon (I know right, I didnÄt thought so as well); to get a glimpse of what to expect from this glass, have a look at Titos review of the original Pfocus (which used the Fujinon glass):

  • this build consists of mostly printed parts and is easy to assemble, the pitfall is the needed precision for the print as well as the post-processing of the parts.
  • Pfocus A needs some additional hardware that you might need to order internationally
  • this build is meant to be somewhat modular, therefore it can be made with different front filter threads, markings in metric and imperial and two (and a half) different mounting options - M75 like a Rectilux Hardcore DNA or Rapido FVD-16a, universal mount with lock-screws in 75mm and (with an additional, provided sleeve) 70mm for native scope use
  • Pfocus A focusses internally, so it's non-protruding/non-rotating front for a consistent vignette as well as better mattebox use

Please mind the .pdf manual for detailed instructions on how to print, post-process and build this variable diopter. It also contains detailed lists of all additional parts and tools needed for this build.

NOTE: even if this project needs precision, it is still a 3D printed device based on a repurposed wide-angle converter and not a precisely machined, properly calculated variable diopter. Don't expect mechanical or optical performance of an e.g. a Rapido FVD-16a or even Rectilux Hardcore DNA.

3D printing settings

Please mind the supplied manual for detailed instructions

3D printer file information

  • 3D design format: PDF, STL, and ZIP Folder details Close
    • Bottom_M75_v03.stl
    • Bottom_universal_v02.stl
    • Dustguard_v02.stl
    • Focustube_noFilter_v06.stl
    • Focustube_v06.stl
    • Fronttray_v09_+0.2.stl
    • Fronttray_v09_+0.4.stl
    • Fronttray_v09_-0.2.stl
    • Fronttray_v09_-0.4.stl
    • Fronttray_v09_0.stl
    • Gears_135T_v02.stl
    • Gears_140T_v01.stl
    • Helicoid_imperial_v04.stl
    • Helicoid_metric_v04.stl
    • PfocusA_manual_v02.pdf
    • rearRetainer_v01.stl

    Learn more about the formats

  • Publication date: 2021-07-15 at 23:13





b | de

I try to create things that make my life easier. Sometimes, I try to make the life of others easier.
It's simple stuff, but it usually works

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