Pi Stand and Slide Holder for the v7 alpha

Hi everyone,

I recently discovered Tinkercad and really enjoy how easy it is to design and edit 3D models. I printed the v7 alpha and noticed a few things that could be altered, and so using Tinkercad I made some custom modifications that I would like to share.

I split the Pi Stand with the arduino and smaller stepper motor boards (which came with the stepper motors):

and the bottom with the raspberry pi:

It slides into the microscope stand, but a little notch was needed since the Dupont jumper wires stick out too much:

There is ample space to connect the LED to the GPIO:

Completed wiring:

Assembled front and back with slide holder:

The slide holder is similar to one I saw in this forum, except I removed edges to allow focusing on the edge of the slide, which is mainly important for blood and bone smears.

I printed the microscope and it’s parts with PETG and PLA+, depending on what’s already loaded in my Ender 3. Both filaments work great, take about the same time to print, and are the same price here.

Below are the stl files exported from Tinkercad:
OpenFlexure Pi Stand bottom.stl (101.7 KB)
OpenFlexure Pi Stand top.stl (69.7 KB)
OpenFlexure Microscope Glass Slide Stage Holder.stl (167.0 KB)

I really enjoy making and using the OpenFlexure microscope, many thanks to everyone involved in this project!


Hi @Noli, thank you for sharing. It is really useful to have a version for that different type of motor controller board. Do you print the OpenFlexure Pi Stand top.stl with supports? You have split the wall with the ports on which makes it stick out below the upper part, but that will make it easier to get the Pi board in with the taller pillars.

Are you using the microscope in the Upright configuration? (it looks like that in the last two pictures) Just as a note for other users who are looking at the standard Inverted configuration, the slide holder is about 5mm thick, which is fine in Upright as there are different sizes for the upright_z_actuator_mount for different sample thicknesses. In Inverted mode it is likely to be difficult or impossible to get the lens high enough to focus. With V7.0-Alpha-1 and Alpha-2 we find that you cannot get in to tighten the optics module even at the design height. The next version beyond V7.0-Alpha-2 is planned to improve the Allen key access and reduce the keyhole length so that design position is easy to get to, and the top of keyhole slot is at the design position. See the merged changes Objective mount improvements (!290) · GitLab. This is intended to make the microscope easier to assemble, but does limit stage sample/slide holders to less than 1mm thickness in Inverted operation.

Yes, for the OpenFlexure Pi Stand top.stl I printed it with supports but oriented it’s side:
It takes about 4 hours at a 0.28mm line height, and the supports are easy to pop off.

Yes I’ve also been trying to get the upright version to align and focus, but it is quite a challenge and gives me more reason to play around with Tinkercad.

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The illumination is likely to be a little too low, but the objective should focus fine. Aligning the objective is a bit fiddly by hand, getting the bolts loose enough to move carefully into position, but tight enough that there is not a big change when you do them up. All being well you only need to do it once :smile:. Have you got the spacer for 5mm samples ( accessories/upright_z_actuator_mount_5mm_sample.stl,
from [ OpenFlexure Microscope - Assembly Instructions]( OpenFlexure Microscope - Assembly Instructions)?

I tried the upright setup with both spacers, but I gave up too quickly… and was inspired to try to make a vertical moving stage similar to the one I have sitting on my desk:

I’m really not sure if it will work at all, but I enjoy trying:

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