wombat2go,
Since the pulse will only be there when you fire the shutter do you need a storage type oscilloscope?
Now mind you, I'm rather early on in my shutter studies and work. But it's becoming more evident that spring replacement is the correct remedy for getting these shutters back to speed--the Betax. Rapax, Compur, etc. This of course is leading to the need to learn spring fabrication, since no parts I know of are available.
If regular users are going to do the naptha-related tricks to get a dead shutter at least working again, then fine. But if you are not following it up with a little tester, so you can make a conversion chart to stick on the back of the camera, then you still don't have much of nuttin'. You'll be all over the place on finding film speeds and development times. Banging your head against the wall.
Find out where your shutter really is, and the rest of procedure will start clicking into place. Voice of experience.
The three Graflex shutters I measured over weekend (above posts) are quite accurate.
This morning I measure a new-in-box Prontor SVS , box says 1957, the shutter is obviously never used.
{ speed, ideal, measured millisecond}
{1/1, 1000, 1600+}, {1/2, 500, 700}, {1/5, 200, 220}, {1/10, 100, 250},
{1/25, 40, 76}, {1/50, 20, 30~50}, {1/100, 10, 12~15}, {1/300, 3, 5~7}
This shutter is slow, and erratic on the 1/50th, note how the 1/10 speed is slower than 1/5
What should be done with it?
I might try - warm it up to 45 C for a few hours, fire it 100 times, then re-measure it ??
My 1913 Compur is more accurate than my modern Copals, Says a lot about German engineering and the strength of their springs
Most important thing to remember with leaf shutters is they need occasional use, that helps keep them running smoothly.
Ian
I sat the Prontor SVS on top of the computer overnight (about 38C) and then gave it a few operations.
It got progressively worse and now the lower speeds do not work at all, the shutter sticks open while the escapement fails to spin up.
The escapement can be made to complete by flicking the lever but it is sluggish.
I downloaded the Gauthier service manuals. It appears mine is an early model SVS (10 ap blades) and the manual notes a few design problems with that model in the first year and later came several versions of the synchronizer,
reduced number of ap blades, and a cosmetic change for identification.
For problem that my shutter has per above, the manual says "Rinse mechanism in pure petrol (gasoline)."
The shutter is not lubricated (strict note in manual)
Grease is only used on the outer time ring and the diaphagm mechanism.
I can see some grease starting to appear on one of the shutter blades.
I might send it to the guy who did my Nettar shutter.
He ultrasonically cleaned that one and it works OK now.
By that, they mean what used to be called "white gas" that is gas with no additives, straight distillate.
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