Comparison of TWX-1 Folded Optics Microscopes from Different Production Years

[woyjwjl]

Okay, considering that I have been exposed to multiple TWX-1 microscopes in the past year. (From 1970 to 1984). I plan to compare the TWX-1 produced in different years (from structure to process) here.

I don't have much exposure to antique microscopes.

To satisfy my curiosity, I will ask questions. If everyone is interested, I will update this post.

Let me share my personal opinion first: the first generation (1970) products had the most extreme (complex) craftsmanship and materials.

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This picture may not explain the problem, but there will be more detailed comparison pictures in the future.

I will cite the relevant content of R. Jordan Kreindler (United States), Yuval Goren (Israel), from "TWX-1 Folding Optical Microscope - The Sovereign of the Kingdom of Folding Optics" in my post. If there is any infringement, please point out and I will immediately delete the relevant content.

English is not my native language. If the wording is not accurate, please forgive me and it would be best to correct it.

[woyjwjl]

The first thing I noticed was the fixing method of the body panels. The body number starts with 1970 and is fixed with bolts (red arrows) instead of riveting. Pay attention to the thread (green arrow).

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What's even more surprising is the "screw hole sealing process", “ a surprising composite of metals and lightweight materials”with almost no visible traces on the surface.
The first curiosity question: What process is this?

Unfortunately, after 1971, independent component design was gradually phased out, starting with the stage bracket and then the side panel(blue arrow), which means this process was abandoned.

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I think this is a compromise on cost and welcome discussion.
Second curiosity question: Are other brands doing the same?

[woyjwjl]

Okay, maybe everyone's not interested, I'll stick with it for a while

As I said:
The early(1970~1971) version of TWX-1 had metal elastic pressure plates around the prism, which were later replaced by cement in order to compromise costs.

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This solves the problem of prism looseness caused by the degradation of cement viscosity over time to the greatest extent, and this reduction is not appropriate

[woyjwjl]

The following is a bit complicated, I'm not sure if I can explain it clearly. Simply put, it's the difference between the "objective wheel bracket".

The top of the picture is from 1971, and the bottom is from 1970.

Arrows with different colors indicate different parts.

The first thing to say is that the objective lens turntable (orange) is an independent component.

Here are the differences:

In 1971, the bracket (red) and column (blue) were separated, and the bracket integrated the runner base.

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In 1970, the bracket and column (green) were integrated, and the runner base (yellow) was separated. It was connected to the bracket through a dovetail groove and two top screws.

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I think this is still a reduction in cost compromise, with adjustable nose wheels that make it easier to calibrate the optical axis.

By the way, the practice of separating nose wheels has not appeared again since 1970, at least so far as I understand it.

[dtsh]

I am interested and enjoying your images and descriptions, just don't feel have anything useful to contribute so have not commented to avoid polluting your thread.
With all of those prisms it looks like alignment issues could be quite the nightmare. I wonder how much degradation there is due to them as well. How is the resulting image?

[woyjwjl]

I am interested and enjoying your images and descriptions, just don't feel have anything useful to contribute so have not commented to avoid polluting your thread.
With all of those prisms it looks like alignment issues could be quite the nightmare. I wonder how much degradation there is due to them as well. How is the resulting image?

Yes, I have encountered prisms with loose cement, possibly due to system design (prism base calibration), which is not as bad as imagined. I just fixed it with glue again (electronic component fixing glue) and still got a good image.

This is a 1977 TWX-1, with images taken directly from a smartphone and only cropped without modification. 90X magnification without oil immersion.

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Thank you for your attention.

[Tom Jones]

How do I tell the year of manufacture on mine? The serial number on the back is 701716.
It does not have the complicated structure of your 1970 model.

[woyjwjl]

How do I tell the year of manufacture on mine? The serial number on the back is 701716.
It does not have the complicated structure of your 1970 model.

You can see the certificate of conformity, if any

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Usually, the first two digits of the serial number are the year of production, at least that's what I've encountered before.

The serial number of the model I am displaying is 700584, perhaps the 584th model from 1970.

As for the difference in serial number 701716, perhaps the manufacturer realizes that this process cannot meet the production requirements

Perhaps tomorrow, I will showcase the last two images, showcasing the other two more extreme structural designs.

[Tom Jones]

I had completely forgotten about the production certificate. I actually have it stuck in the case! The scope was in my display cabinet. I even had the seller translate the Chinese labelling for me after I bought it.

It is Product number 701716, Inspection date: 1971-1. The Inspector was #08. The full number is engraved on the microscope body, but the certificate appears to have only 01716 stamped on it.

Thanks for the reminder!

[deBult]

Interesting comparison, thanks for sharing!

[woyjwjl]

I will share two detailed designs here at the end.

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The red arrow represents two pits, while the green arrow represents a spring that lifts the ball (not shown) and then slides into the pit. Yes, this is to achieve a sense of paragraph when the filter is moved. Do you remember the sliding polarizer on the NIC?

If you don't have a deep impression of the previous design, the next one will definitely touch you.

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The red arrow represents the spring, while the green arrow represents the jbckscrew. They exist only to provide damping when positioning the nose wheel base. Okay, I think of the 'technological surplus' of German cars in the 1980s.

The additional fine adjustment knob is the outstanding feature of TWX-1, and the blue arrow represents the spring steel plate, which is the key and can be seen fixed by 8 bolts. This design was preserved until 1984......


Thank you for watching and welcome to comment.

[abednego1995]

Thank you, this is probably the best throughout review of the TWX-1 out there. I personally own one, but enjoyed comparing it to yours from different manufacturing dates.