Film-Tech Forum ARCHIVE: Potts Platter (W/Microswitch) Problem With Thrown Print

This is topic Potts Platter (W/Microswitch) Problem With Thrown Print in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Patrick Matthews (Member # 2705) on 12-17-2005, 05:57 PM:

I am running the Potts Platter with the microswitch model brain and a Pro-35 Projector. Today I noticed that the payout from the brain was lagging a bit. The brain was letting the film wrap about halfway around and then it would catch up. While I know this wasn't right it wasn't huring anything at the moment. I then ran a show from my bottom platter deck with the same brain, same problems. This time however when it got about 3 minutes from the end of the print the platter was going so fast it through the remaining part of the print off the platter. Is there an adjustment I need to make on the brain/microswitch or is the thing going bad? BTW, it was working fine yesterday.

Posted by Mark Gulbrandsen (Member # 72) on 12-17-2005, 07:08 PM:

Sounds to me like you have the older micro switches. If it takes a half a turn or more of film wrap to get the switch to click on that itself is the clue. You need to get three new micros that have .5 oz bat tennsion on them. These .5 oz micros will make the Potts, or Strong platters run incredibly smooth. Be sure to get them from a dealer that KNOWS about these switches, or order new ones from Potts, but they are generally less expensive from a dealer. We buy them in bulk at least 100 at a time.....

ACHTUNG!... IMPORTANT!!! Replace them every two years no matter what for trouble free operation. Be sure the switch clicks in the middle of its travel annd.....they have also been known to stick in the on position. Sometimes the contacts will weld themselves together..... [Eek!]

Mark

Posted by Aaron Mehocic (Member # 15) on 12-17-2005, 09:19 PM:

By older microswitch do you mean the kind with the little wheel on the end of them? Few years ago I was told they don't even make those anymore.

Posted by Patrick Matthews (Member # 2705) on 12-18-2005, 12:08 AM:

if that is what an "old" microswitch is then I don't have one (unless you are talking about a wheel that isn't obvious)

Posted by Monte L Fullmer (Member # 2797) on 12-18-2005, 02:22 AM:

..check your motor brushes while you're at it. Tired brushes could cause platter rotation to lag and eventually stop.

I thought it was my switches (on a Balco platter, which is like the Potts..and which I converted the brain to the newer blade type as what the newer STRONG brains uses..with a bit of modification and this conversion that I did makes the brain run TONS better than those roller type switches), and found out that one of the motor brushes have seen better days. Sudden changeout of brushes got this deck up to normal operation (in as well as the switch conversion..)

-Monte

Posted by Dominic Espinosa (Member # 2122) on 12-18-2005, 10:25 AM:

I'd check and see what the microswitch is and get the next one down.
I.e. one that needs less force to opperate the deck. I think I saw something about that on here a while back.

Posted by Monte L Fullmer (Member # 2797) on 12-18-2005, 01:50 PM:

quote: Aaron Mehocic
Few years ago I was told they don't even make those anymore.

Oh, no. They are still being made from numerous manufacturers that would charge less than STRONG.

Posted by Patrick Matthews (Member # 2705) on 12-19-2005, 09:23 AM:

Are these microswitches hard to change out? I am fairly new to projection and was kind of forced in without much training (I run a single screen so I have little help around).

Posted by Brad Allen (Member # 470) on 12-19-2005, 01:11 PM:

No not hard at all. Two wires, and two nuts. After you install the new one, adjust the micro switch so you hear it click at mid travel of the arm. Then tighten the hardware down.

Posted by Monte L Fullmer (Member # 2797) on 12-19-2005, 01:16 PM:

You might have to check this a few times before tightening down the hardware for the proper travel.

[ 12-19-2005, 05:08 PM: Message edited by: Monte L Fullmer ]

Posted by Louis Bornwasser (Member # 3063) on 12-19-2005, 03:46 PM:

Tension is pretty tricky. I use gravity to find the exact place where the least tension is found then lock down the hardware. Louis

Posted by Mark Gulbrandsen (Member # 72) on 12-19-2005, 10:59 PM:

quote: Monte L Fullmer
Oh, no. They are still being made from numerous manufacturers that would charge less than STRONG.

Monte,

There is really only one manufacturer of this switch I have found over the years that actually works reliably over a several year span and thats the one made by Microswitch. I like the old saying....There may be others that fit but there is only one that really works [thumbsup]

.

Mark

Posted by Monte L Fullmer (Member # 2797) on 12-20-2005, 01:05 AM:

Hey Mark, Is Microswitch the one that you stock there at Claco?

Posted by Gordon McLeod (Member # 33) on 12-20-2005, 08:44 AM:

I have been using the equivelent from Omron for years and it has proven stable and reliable

Posted by Monte L Fullmer (Member # 2797) on 12-20-2005, 12:29 PM:

That is what I use now are the Omron switches is pleased with them. I've heard that Honeywell switches are good as well.

Posted by Jon Miller (Member # 163) on 12-20-2005, 01:13 PM:

Microswitch has been a division of Honeywell for at least two decades, but AFAIK Honeywell phased out the name a few years ago. Whether the logo says "Honeywell" or "Microswitch", the quality should be the same.

Posted by Lance C. McFetridge (Member # 95) on 12-20-2005, 05:08 PM:

Be sure to take the spring out from behind the tang.

Posted by Patrick Matthews (Member # 2705) on 12-22-2005, 01:56 PM:

Ok, I ordered a new brain (we only had 2 so I though always good to have a back up) mostly because it would then give me some time to fix the others that we had. Took it out of the box and put it on the platter and started running a show and it is doing the exact same thing, wrapping around twice and then catching up. I doubt this brand new brain could be bad so what else could be doing this?

Could this be a problem with my take-up plate?

Monte: Are the brushes hard to change out and you can you tell if they are bad and need to be replaced?

[ 12-22-2005, 03:34 PM: Message edited by: Patrick Matthews ]