8mm Forum: ELMO projector problem

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Posted by Gary P Cohen (Member # 4417) on November 21, 2017, 02:23 PM:

I recently bought a used ELMO Hi ViSion SC 18M 2-TracK 8mm Sound PROJECTOR, the one with the preview screen attached. Interstingly enough, the projector works fine in the forward mode, and projects properly in forward with the lamp lit BUT it continues in forward when the knob is turned to OFF, and the projector turns off ONLY when in the knob is in the rewind position! Anyone ever come across this or can offer a solution? Thank you! Gary

Posted by Steve Klare (Member # 12) on November 21, 2017, 03:16 PM:

This is an interesting one!

If this is anything like my machines (and the odds are very good) your motor control is done by a set of switches which are pushed by the lobes of a cam on the control knob shaft.

-something like this: when the machine is supposed to be going "forward", one switch is pushed so that that motor terminal is connected to (+) and the other not pushed so that terminal is connected to (-). For "reverse" the opposite happens. For "stop", neither of them is pushed so both terminals are connected to (-) and there is no voltage to drive the motor.

There is also a lobe and switch to turn the lamp on and off.

I wonder if maybe one of your switches is stuck always connected to one side of the power supply, so that when the other switch is connected to other side in "stop" there is still voltage driving the motor. (One time my lamp wouldn't turn off in "stop" because I had a switch that was stuck.)

When you go into rewind, your stuck switch is connected to the same terminal as your working switch, there is no voltage across it, so now the motor stops.

PS: Did you know you live in a state that has a film collectors' convention twice per year?

Posted by Gary P Cohen (Member # 4417) on November 21, 2017, 03:59 PM:

Thank you for your comments. I grasp what your saying, but I think I'll need to get someone more mechanically inclined involved to help. I have bud I can ask. How do I get info on the gathering g- is it the one down the Jersey shore?

Posted by Steve Klare (Member # 12) on November 21, 2017, 07:30 PM:

This is the one in Wildwood: milepost 4 on the Garden State Parkway. (-not too much further south you start to see Penguins!)

If you go into search in this forum and look for "CineSea", you will find enough reading material to last you days!

This is what I call a Two Beer repair: challenging enough you will deserve both of them (pays to wait until you finish the job...)

What you have is a stack of switches and insulators held in place around the control shaft by steel plates and a couple of long screws.

Replacement switches should be easy enough to find, but they need to be soldered to their wires at the correct terminals.

I did one of these once. I only did that one switch for the lamp. In hindsight I would have been wiser to replace all three while I was at it: it may come back to haunt me some other time.

Where it gets sticky is getting it all back together. I found the best way was to stack all the stuff up on the screws and then flip them over as a unit, put it in place and snug the screws down.

(Take pictures every step of the way and keep the parts organized as they come out.)

-by the way, everything so far is just theory. It's smart to go in with a voltmeter and see if I'm actually right before anybody digs into this.

Posted by Gary P Cohen (Member # 4417) on November 24, 2017, 10:04 AM:

Thanks for all the tips - Cinesea and on the projector. I grabbed the beers so far [Smile]

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