The enlarged aperture of the camera, proposed by Instructables under the nickname jwkooi, can serve as a visual aid in the physics classroom or at the courses of photographers, or it can simply be an adornment of the interior of a photo salon or an avid amateur photographer’s apartment. Homemade It contains an operating mechanism arranged and working similarly to a real diaphragm.
From a similar device proposed here the author of the same site under the nickname Sidneys1, the proposed design is characterized by the use of plywood instead of cardboard. This slightly increases labor costs, but strength increases with them.
The master begins work on the layout with the manufacture of two identical plywood disks with a diameter of 210 mm, each with a hole with a diameter of 120 mm in the center. Plywood thickness - 3 mm. Each of the disks is marked by the master, dividing into 8 identical sectors.
On the lines of dividing sectors on one of the disks, the master cuts through slits 3 mm thick and 35 mm long. If the screws moving along the slots have a diameter other than 2 mm, the width of the slots must be taken 1 mm larger than their diameter.
The master performs the petals of the diaphragm in a way that has proven itself in aircraft modeling. According to the sketch, he cuts out two identical patterns from the woodworking waste and drills holes in them. Using these holes, he collects a bag of both templates and eight rough blanks of petals from plywood. Processes until the blanks repeat the shape of the patterns. Parses the package.
On one of the disks in which there are no gaps, the master attaches the petals using the M2x10 screws and nuts as shown below. He separates all moving parts from stationary ones with plastic washers, but he believes that with metal he also works. Screws M2x25 screws into the holes at the opposite ends of the petals and fastens them with nuts.
Using two sets of petals compares in what positions they will be with a closed and open aperture:
From the old tabletop with a thickness of 18 mm (MDF coated on one side), the master cuts two rings with an outer diameter of 230 mm and an inner diameter of 185 mm. In each of the rings drills 16 holes with a depth of 10 mm for the pins.
Installs the pins in the holes in one of the rings (does not put two pins, so that you can then install the lever). Places a disk inside with no gaps and with petals.
It covers from above with a disk with slots so that M2x25 screws at the opposite ends of the petals pass through them, checks the operation of the diaphragm, removes this disk.
Saw in a bar from woodworking waste such a groove:
It cuts small holders from this strip, and with their help it fixes the disk with slots on the opposite ring so that it can rotate freely in the grooves.
Putting it all together, checking again, and the figure on the table is “posing”:
And finally, it makes and installs the lever as shown below, so that it rotates the disk with slots, and that, in turn, simultaneously moves all the petals, opening and closing the diaphragm.
The aperture layout is ready. The Instructables member under the nickname olathorsen repeated it, applying rings not from MDF, but from thick plywood:
If you prefer a similar aperture layout, but with copper petals, I recommend this design (author kommodore, translator pogranec).