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Remote Control Solenoid Question
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wiux
Joined: 04 Jun 2019
Posts: 43
PostPosted: Mon Mar 22, 2021 11:16 pm   Post subject: Remote Control Solenoid Question

Hello, I was wondering if there were any guides to using the solenoid (#2 in my case) as a remote control shutter release?

I saw an example in a video (https://www.youtube.com/watch?v=NCMVHarqnwc), but I'm not really that handy so I don't want to mess anything up. Consequently, I also have no idea what he's using for the plugs into the solenoid (they look a bit thinner than banana plugs to me). A quick search on this forum showed voltage is important, but I don't really know how to control for that either, as the one he's using seems to be pretty high at 12V DC (https://www.ebay.com/itm/315MHZ-DC12V-10A-1CH-Wireless-Relay-RF-Remote-Control-Switch-Receiver-Transmit/262971219001?hash=item3d3a4e5c39:g:pg4AAOSwwcFcerFu).

Any ideas/guides/other examples?
wiux
Joined: 04 Jun 2019
Posts: 43
PostPosted: Mon Mar 22, 2021 11:21 pm

Oh, also on the subject of shutter releases, is there a preferred auto timer for large format/Graflex? It doesn't have to be mechanical, even though I'm guessing the vast majority (if not the entirety) are.

I'm in the process of getting a Kodak self timer that clips onto a cable release (as opposed to the more common variant that screws directly into the lens/shutter like a release itself), but wasn't sure if that would harm the shutter over time or not as it seems to have a very deep push. I'm also unsure if it'll work with the cables I have or if it requires a vintage one.

I had a Knips knockoff that worked OK, until it died one day (I'm guessing the mainspring broke at last), so I thought I'd try a different kind after reading the Kodak ones were very tough.
45PSS
Joined: 28 Sep 2001
Posts: 4081
PostPosted: Tue Mar 23, 2021 2:00 am

It is my understating that solenoids are current dependent. The service manual says a 3 cell synchronizer handle is needed. The 3 cell synchronizer supplies 4.5V and up to 7 amps of current with fresh batteries.
In the video pins that just fit the electrical connections on the solenoid are in the solenoid and the power supply is connected with jumper wires with alligator clips on the solenoid end.
New batteries read .1V to .2V above label voltage on a volt meter and will need to be replaced when they reach label voltage in cameras and most other electronic devices.
A 6V power supply capable of producing up to 10 amps will work fine with the solenoid as the solenoid will only pull as much current as it needs provided the voltage is adequate.
The vintage self timers are mechanical. They will not damage a shutter. Most cable release throws are 5/8 inch but some were 3/4 inch and are rare. Some cable release have a flat tip while others are rounded. Some shutters have a .030 thick release lever that the cable release contacts and the rounded cable release will slip off the edge of the release lever, filing the end flat solves the problem. Other shutters use a pin with flat ends to contact the cable release, rounded and flat end cable releases both work on this type of shutter. Mechanical self timers have the same type of end as cable releases.

Paramount Cords tip #40 is for a Graflex Solenoid and should fit other makes of solenoids.
https://paramountcords.com/product/custom-cord/

http://www.southbristolviews.com/pics/Graphic/manual-pdf/GrafliteManual.pdf
says that 2 cell synchronizers can be used with the solenoid. A 2 cell synchronizer produces 3V nominal. Although not stated the solenoid probably requires 2 to 4 amps of current to operate.
wiux
Joined: 04 Jun 2019
Posts: 43
PostPosted: Tue Mar 23, 2021 2:51 am

So just to be clear, there's no risk of damaging the solenoid with a higher voltage/amperage then? You mentioned 6V10A, but the battery is rated at 12v10A. Am I understanding right that the solenoid unit won't be fried by too much power because it'll only draw what it needs?

I must confess I'm not terribly savvy when it comes to electronics--my only prior experience comes from soldering a lot of LED strips in parallel to make a UV lightbox for cyanotypes.

My plan now is to get the custom cord from Paramount with an unfinished end (thanks for the link! I'd only ever ordered the PC sync chord from them before & didn't think to check for solenoid cords), & screw it to the RC battery terminals, hopefully being able to correctly distinguish the positive wire from the negative one.
45PSS
Joined: 28 Sep 2001
Posts: 4081
PostPosted: Tue Mar 23, 2021 3:45 am

Quote:
So just to be clear, there's no risk of damaging the solenoid with a higher voltage/amperage then?
Yes there is but you would have to go to 24 or 48Volts or higher to do it.
Solenoid have two ratings, pull down current and hold current. If you are planning to do very long exposures then do some testing. Very long times at pull down current will shorten the solenoids life. The longer the solenoid is energized the hotter it will get, the hotter it gets the sooner it fails.
The Graflex solenoid manual does not state the pull down or hold currents or the time limit for long exposures.
wiux
Joined: 04 Jun 2019
Posts: 43
PostPosted: Tue Mar 23, 2021 4:34 am

Thanks! I probably won't do very long exposures (even if I did, I'd use T instead of B) so there's no worry about that. I appreciate your help/advice!
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