Home  1: Introduction and research  2: Basic parts and materials 
3: Initial test box  4: Framework mockup  5: Designing lens and aperture mount 
6: Designing camera back and film holder  7: Design tweaks  8: Film holder construction 
9: Camera back construction  10: Camera aperture failure  11: Camera aperture success 
12: Camera back framework  13: Camera shutter  14: Ground glass 
15: Camera front framework  16: Bellow test 

CHAPTER 10: CAMERA APERTURE FAILURE

This thing proved to be harder than I thought to build, and Iīm thinking of admitting defeat and go for a more simple solution for the aperture, that with switchable cards with a hole in them, to not ground the project to a halt which is the last thing I want, I do have a day job and some kind of life beside that and this project... at least I have to cook some food for me and my girlfiend every other day. Although my research and plans for this little mechanical thing is all correct I found that itīs very hard to create the parts with enough precision by hand. This thing works, but the ring gets hard to turn and the reliabilty will be very low, the blades tend to get stuck here and there and if too much force is applied things will start to bend and flex, thus making the whole thing very inexact. Maybe this is the reason why people donīt build their own apertures in paper and cardboard all the time :) The white parts seen in the image below are stryrene plastic I bought at the hobby store. Another problem here was the circle cutter I bought, which was rubbish to say the least, the whole thing is in plastic and bends and flexes all over the place when trying to cut stuff with it, which means the circles sometimes get far from circular, and in many places it doesnīt matter, but here it definitely does. I guess I could go into building a proper circle cutter as well :D but Iīm not really interested in more than one project at a time so I wonīt bother doing that. I guess that one positive thing with going for the simpler aperture design will be that the camera front will get thinner.

Camera aperture parts.

Below you can see one of the aperture blades. The small pins I is made from small brass screws that I bough from the hobby store. What I have done is just cut of the part with the threads. The white thing is a small plastic strip I added to add strength to the blade between the pins where the force from the outer ring will be applied, as noted above they didnīt work as good as I thought they would.

Aperture blade.

Continue to chapter 11: Camera aperture success

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