GS 1200. The rear arm is very slow.

[Graham Ritchie]

Sorry to hear this Melvin, so what can we do? well I doubt the motor will run on a single brush, so that's out, find some new brushes? well that's ideal but where? I don't no. Thomas might be able to help here. A new motor, well that's the ideal situation, but where do you find one these days?.

In the past Melvin, folk just replaced the motor, fine back then when there were still parts around but after 40 odd years where do you find them the thing is Melvin at least you tried to fix it. Its been years since I did mine and to date the take up is still running fine.

Now the only thing I would change in regard to fixing the motor, is to remove the motor totally from the projector, doing so would mean removing the armature along with the brushes as a complete unit moving it forward through the outer casing, doing so, making access to those brushes for removal a lot easier.

All of this does not help you and I do understand that, just thought I would say this while its on my mind, as others might be watching and thinking of giving it a go.

The fix for you Melvin, I am not sure what to do here, except trying to find brushes, but better still another motor, even in this case some have different voltages. One last attempt might be a motor swap using the forward rewind. I think they are the same, however that would mean no rewind

To be honest Melvin I really cant think of anything else, hopefully Thomas will come up with better ideas than what I have floated, but I will say this, without new parts Melvin at least you tried to fix it and that's something, just got to come up with a plan "B"

[Brian Fretwell]

I would say that without the second brush the circuit couldn't be complete so the motor wouldn't work but nothing unpleasant would happen if you tried as no current would flow!

[Matthieu van der Sluis]

The old racingcars have brushes onderneed.

I used to make the brushes myself for those cars, by bundling the inside of electric cable and solder a bit on one side, keeping it it flat, and cut it to the right length
they just function for contact.

The reason I'm bringing my GS1200 to a repairman soon, is because my projector was behaving strange, running a bit in a various speed.
Not sure the motor was causing that.

[Graham Sinden]

Melvin, I would do as Graham suggested and swap with the rewind motor then you can at least watch films on it (hopefully) and just rewind elsewhere. It's a temporary fix until you can get both working.

Graham S

[Melvin England]

Graham - That is probably what I will do as I have a separate rewind system elsewhere. I think you and another person have both suggested this and is a very sensible idea.

Also, John Burgess sent me some advice through a PM which I have thanked him for, which I could follow through with after your quick fix to the problem.

.

[Thomas Knappstein]

I have used this ones from China. Bought them on Ebay and they are working very good.
You have to cut them into the right Length from 6mm. Then bring the Radius from the Colector onto the Front Side of each Brush.
They must stay perfectly in Contact with the Colector. Then let the Motor himself without any Gears run on a 12V Power Supply for 5 or 6 Hours.

[Melvin England]

The state of play at the moment is this......

I tried to remove the remaining brush from its socket to try and measure it. I find it is attached to a tiny piece of wire that probably provides the "spring" pressure on the brush to keep it in contact with the motor. Therefore, what I intended to do which was to remove a brush from the front arm to put in the vacant slot on the rear is just not possible. I did find a way to measure the brush which is 3mm x 3mm x 5mm. I have scrawled through all the Ebay sites to find this specification but to no avail. I have found something VERY similar, so I will buy it (£5) and try to grind it down to the required length, although I am not certain how I am going to deal with the "spring" effect.

Thomas - Thank you for the information. I think I looked at that site and couldn't see anything similar.

Graham's R & S - You suggest moving the complete front rewind motor to the back and vice versa. Are you referring to the electronics attached to the round disc that needs to be unscrewed in the first place ? This would also mean snipping the red and blue leads and re-attaching I assume.

I will invest my £5 and order the brush and see what happens when it arrives.

I will keep you posted. Any more comments are welcome.

Thank you.

[Melvin England]

Well, the brushes arrived.

Opened the projector / rear take up spool motor. The brushes were a sliver too big. So, assuming it was a big job to file them down, I headed for the garage and some metal tools. Not needed. I was astounded to find that the brushes could be ground down using...... sandpaper! It was that easy! Pity the rest of the day wasn't.

To cut a long story short, I faffed, fiddled, cursed, re tried and retried and retried. Eventually the brush did go in the slot. Success. BUT it was stuck. After what seemed forever, I managed to get the existing brush to grab the shaft and eventually after many attempts, managed to close up the motor unit as it should be.

Now.... the big turn on.

Did the arm work?

Like hell it did.

So I am feeling oh so frustrated at the moment. I need to calm down, walk away from it and return some other day when I am recharged.
I think my next attack will be to file down the new brush even further so it just slips in and out of its bracket. Maybe that will work.

I am reluctant to swap motors with the front arm. I assume if I did, it would be okay to snip the thin red and blue cables and re attach using masking tape ? The connection of these leads to the rear board is totally inaccessible. Could anyone confirm whether or not this would be acceptable?

Oh well, my opticals, and 1200's are going to have one mighty rest if I can't sort this out.

.

[Matthieu van der Sluis]

Have you tried a new brush?