Film-Tech Forum ARCHIVE: Speco LP-270 Platter Trouble

This is topic Speco LP-270 Platter Trouble in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Michael J. Barr (Member # 976) on 01-29-2002, 10:48 PM:

The bottom platter keeps on locking up (refusing to budge) every once in a while. I am new to these platters since I just transferred here, so I would like some suggestions on what to look for. Currently, we are not using the platter in fear that it will lock up again sometime mid-show. Anyone have suggestions?

Posted by Wes Hughes (Member # 981) on 01-29-2002, 11:34 PM:

The deck bearings might be damaged. I have seen this happen if someone trys to lift the platter deck off the spindle improperly...ie they lift the top bearing off the spindle and then lean the deck to the side. That will break the bearing race and could cause your seizing problem.

These bearings are easy enough to replace...first check to make sure its actually the deck bearings though....when it seizes up, pull the motor away from the disk and see if it is the disk that is stuck, or the drive motor shaft.

Posted by Darryl Spicer (Member # 711) on 01-30-2002, 10:00 AM:

Never remove a platter deck from a speco and think you can put it on another shaft. The older specos had the platter decks matched to the shaft and were numbered for instalation. If a deck has bee swapped with another deck someplace else the shafts may not be matched causing it to bind up. I have never encountered this problem before with a speco and I have been working with them for 10 years now.

Posted by Adam Martin (Member # 641) on 01-30-2002, 10:47 AM:

By "refuses to budge" do you mean you physically cannot turn the platter or do you mean that no matter what you do with the feed arm in the brain, the platter won't motor?

Posted by Randy Stankey (Member # 64) on 01-30-2002, 12:14 PM:

Mike;

To make a long story short, the deck you are talking about. (#7) is damaged. I sent you an e-mail about it. Get back to me on my personal e-mail account and I'll tell you all the details.

Posted by Paul G. Thompson (Member # 655) on 01-30-2002, 07:21 PM:

Possible problem. A screw coming up from the bottom of the pay-out head could have loosened up, and dropped down a little to foul the outriggers. This happens once in a while to CFS and Strong A-3's....

Been a while since I worked with a LP-270, but it is just a possibility.

Posted by Bill Langfield (Member # 818) on 12-31-2002, 11:30 AM:

Hi all, Its been a long, I was kind of gagged (to THINK before I post, get the FACTS) just got to behave.

Speco Platter

What exactly does the BLUE 'Breakdown' button do, I thought it might release the 'brake' on that motor, that is to open circuit to the motor, to let it free run rather than trying to turn into a generator. That could be all completely wrong.

The reason I ask is, because the blue button seems to have no effect whether it’s selected or not.

I was hoping it was the lower the ‘holdback’ tension of the plate while breaking down.

Cool taking 6-5-4 down to 6000’s. Cool taking 3-2 to the next 6000, but when it gets down to reel 1 and the
head program, the poor old MUT is going very slow and slipping, and starting to smell, so I know it’s not doing
that giant roller in it any good. (The old wood-grain MUTs didn’t care, they just went 1 million miles an hour!)

My solution to this day been to jam a paint brush handle between the motor shaft and where it slots threw to arm completely remove tension, however this often makes the film ‘bounce’ as it is taken up to the 6000 and
I need to stay and hand tension it.

So what does that blue button do and what do you when down to that tension load last 2-3 thousand foot?

Have used versions of Speco 3 tier double take-up elev-roller, 4 tier single take-up elev-roller (the best one)
And…
What’s this SPECO?
A 5 tier with some weird digital control that worked out which plate had a brain in it and which plate had
a take-up roller plugged in, from there it knew what to do, it had LEDS all over the place where buttons normally are
Thing was a mess, it got sent back, in months. That was about 5 years ago, heard of that model? Anyone, using one?

Regards BILL!

My next question will be ‘What the heck size are they using the hex/allen keys, Metric Nope, Imperial Nope.

Funny Dumb Thing
I was going to take photos of the take-up elevator for above question, however I forgot because I was more
Interested, in watching the Sydney Harbour Bridge 9pm New Years fireworks from the roof of the theatre.
Couldn’t see anything so got higher and was hanging on to an air condition plant thing in gusting winds,
at 9.07 I thought this is nuts and got down. Turns out the reason I couldn’t see anything was because they
cancelled, due to the high winds!! No wonder I was bit worried up on the roof, in the dark.
Got to see the Midnight Fireworks at home on TV though. So there ya go.

I will supply more accurate info next message (re: Speco thing, not about being on the roof thing)
Just thought I get this out now, while it’s in my mind.

EDIT: Just thought, I BET Allen keys come in AF (American Fine) Doh!
Just got to find a set now!

Posted by Steve Guttag (Member # 268) on 12-31-2002, 12:49 PM:

The Blue breakdown button on the platter allows the "BRAKE" switch on the MUT to put tension on the platter to bring the film to a smooth halt from high-speed...almost no one uses this feature and some specifically recommend not to use it.

Steve

Posted by Bill Langfield (Member # 818) on 01-01-2003, 04:04 AM:

Steve,

Thanks for that, that explains the blue button then. Yes I never use as I couldn't figure what it does, that would because when I'm slowing the MUT waiting for the join, I slow the platter plate gently by hand.

What do others do about my other problem, where the MUT is struggling pulling the last few thousand feet off?

Bill.

Posted by John Eickhof (Member # 323) on 01-04-2003, 12:34 AM:

Actually, the 'blue' button also applies a minor voltage across the motor to help the breakdown of the print,it allows the brake option to work. I have had no problem with these in 20 years! These motors are a field wound type, there is a set of field windings (120 Vac) and the variable speed windings that are controlled by the variac. Thus, the 'blue' button activates the field, and will produce LESS drag on breakdown!!

Posted by Bob Peticolas (Member # 328) on 01-04-2003, 07:29 PM:

On the LP-270 the weakest link seems to be the button switches. Your problem, assuming it's electrical and not mechanical, is familar. You didn't say if the stoppage was during takeup or payout. If it's in one mode and not the other, then it's definitely one of the switch contacts. In fifteen years of regular usage, I've had to replace two of the three switch assemblies (I don't know how old our platters are, they may have had many years of hard usage before I got them).

If wiggling the button for the mode you are having trouble in fixes it (if even for a short time) then you are in for a replacement job. Replacing one of these assemblies is about an hour job, the new ones from SPECO have a PC board with all of the wire holes labeled. If you can solder, you can replace it. [thumbsup]