Film-Tech Forum ARCHIVE: Christie AW-3 Platter photosensor replacement

This is topic Christie AW-3 Platter photosensor replacement in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Ethan Dutcher (Member # 8319) on 06-28-2014, 10:24 AM:

I have a 5 platter Christie AW-3 that has an issue. It looks like the photosensor "upgrade" kit was installed in this platter system, however one of the "discs" was not changed to the new type(the crescent discs, I'm sorry I don't know the name of them). The old discs have a lot of black and little white holes, the new disc just has numerous black lines. Right now the platter with the old disc has no differentiation between 0 and 50% on the payout assembly, then jumps to almost full speed(surprisingly it seems to take up without any issue). I know is isn't the timing, the platters with the new discs I can time perfectly. Does anyone have a copy of the instructions for changing these assemblies? I know the kit came with one but it isn't here. My current goal is to simply remove the top platter and use it's assembly to get the bottom four working. We only ever really have one 35mm print in house at a time, I'll never need all five platters.

Posted by Mark Gulbrandsen (Member # 72) on 06-28-2014, 10:33 AM:

I've seen the sensor disks for sale on Ebay... Item number 271328881104. He has both types of these available.

Posted by Jim Cassedy (Member # 4115) on 06-28-2014, 11:33 AM:

quote: Ethan Dutcher
Does anyone have a copy of the instructions for changing these assemblies?

It really 'isn't rocket science', as they say.

There are detailed 'exploded parts diagrams' in the manual for the AW3R, which you can
find in the "warehouse" section of this website.

That should be all the info you need to help you figure out how do do what you want to do.

Posted by Kerry Fleming (Member # 1657) on 06-28-2014, 11:47 AM:

You may want to check your LED & Photo Cell (192847-002) to be certain it will trim. Pull platter, take out hub, take off old filter, remount new filter, and have fun re-tensioning spring. Put it all back together. Wala your Done! (Calming music in the background helps too.)

Posted by Mark Gulbrandsen (Member # 72) on 06-28-2014, 12:00 PM:

And while it's apart check the single ball bearing to make sure it isn't bad... binding or sticking... they do have a bad habit of getting crud inside them because they are only shielded bearings... not sealed. And they should not be greased, just oiled! Clean the lower Teflon bearing as well and the shaft. Do not overtension the spring... use just enough tension to make it consistantly return slowly to the stop position. You can test it outside of the arm but be sure it is sitting level. Follow Brad's LED adjustment procedure and you're all set.

Mark

Posted by Ethan Dutcher (Member # 8319) on 06-28-2014, 12:17 PM:

I can take apart the hub no problem what-so-ever. Putting it back together with the correct orientation and the spring actually working is what I'm currently running into trouble with. I cannibalized the filter disc from the top platter and put an old disc in to try to figure out how to get it back all together properly. II had a TON of trouble with that spring trying to get it back to a point where it will actually pull the assembly, so I'm not certain how to get that done correctly. I got the hub back in to a point that looks correct, I can move the disc freely from underneath and it pulls back with the spring. It looks exactly like the other hubs. But if I put the payout assembly in, the control arm on the payout assembly immediately goes to the 100% mark and won't move backwards. Obviously I am missing something with the proper orientation of the components of the hub. The instruction manual has a picture of everything. However it has zero details on how to get it all aligned, I've just been going on how the other platters look from underneath.

Posted by Louis Bornwasser (Member # 3063) on 06-28-2014, 01:34 PM:

It sounds to me that the disc is not indexed correctly to the zero point. Either that or the payout assembly is misindexed.

Do you have the same problem with all of your payout assemblies?

Posted by Brad Miller (Member # 2) on 06-28-2014, 02:42 PM:

His problem is very simple and he said it in the first sentence. He has the new infared LED mated with the older filter. That simply won't work. He MUST have a new filter with the curved lines in it, not the little dots to use that LED.

Posted by Kerry Fleming (Member # 1657) on 06-28-2014, 06:20 PM:

Setting tension (Too much/Too little)on that spring is not fun. Pulling arm to 100% could mean spring is upside down or wound in opposite direction. Must be careful with hub plate orientation and spring stops on the filter assembly. I'll set it up & partially install it a few times making sure tension is right and, filter clears between LED & cell. Good cup of coffee & soothing music minimizes my frustrations when I need to work on that @#!! spring!

Posted by Mark Gulbrandsen (Member # 72) on 06-29-2014, 01:07 PM:

After you've practiced with that spring a few times you'll get the hang of it.