Film-Tech Forum ARCHIVE: OK, here we go again...

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Posted by Aaron Sisemore (Member # 145) on 03-16-2000, 11:55 PM:

As reliable and trouble-free Simplex machines are.... I have a problem with one that defies detection of whats causing it...

its a 1989 vintage Simplex 1050.. problem is there is about 1/2" of play in the vertical shaft. To be more precise, you can rotate either of the feed sprockets which are usually solid, about 1/8 turn in one direction. When this happens, the vertical shaft moves upwards about 1/2 inch, as the sprocket shaft gears are engaged with the gears on the vert shaft. I release the sprocket(s), and gravity returns the shaft to its original position. I have looked EVERYWHERE on the vertical shaft, and cannot see where there is any kind of lock-down or setscrew, collar, or anything else that would prevent the shaft from moving up or down.

This has been going on for about a week and a half with NO interference with picture or sound, and it does not make any abnormal noise from the gear train (when the machine is running the shafts pretty much stay put)

However I got a call today saying that now the shutter timing is beginning to stray during the course of a film's run requiring the shutter knob to be adjusted one or more times during the film, still no abnormal noises or picture unsteadiness. I need some advice or suggestions before this causes this machine to do something very unpretty on its gear side taking a screen down and causing me to have to make an almost four hour trek to Angel's Camp to fix it.. HELP!

Aaron

Posted by Pat Moore (Member # 380) on 03-17-2000, 11:23 PM:

Hiya;
The lower bearing of that vertical shaft assembly is clamped in place -- sounds like it's loose. Problem is that you have to remove the vertical shaft assembly, as I remember, to get to the allen screw that clamps on it. Can you do it? I'll be glad to describe the procedure, but the vertical is a very critical piece to reinstall correctly. Be sure...

Pat Moore

Posted by John Eickhof (Member # 323) on 03-17-2000, 11:42 PM:

Yes, thats probably it! Remember, to remove the lower sprocket assy first, and the intermittent flywheel! Take care when re-tightening the collar on the lower
bearing as they have been known to fracture
the housing if too tight! Proper tension is when the upper sprocket drive gear is against the top bearing with the spring washer slightly compressed. You better do this soon! If the baering comes out of the casting, disaster will strike! The damage will be severe! Good luck!

Posted by Pat Moore (Member # 380) on 03-18-2000, 07:11 AM:

Hi all;
This is one reason we made a change in design of the Simplex Vertical Shaft late last year. Rather than clamping that bearing, we now locate it with a snap ring to "load" the wave washers at the top of the shaft. This eliminates loosening of the assembly and potential cracking of the casting if you're too enthusiastic.
It is a challenge, not to reset the bearing tighten the screw correctly, but to remove and properly reinstall the vertical. Let m eknow how capable you are, be glad to help.

Pat

Posted by Aaron Sisemore (Member # 145) on 03-18-2000, 02:42 PM:

The vertical shaft *MUST* come out to reach the setscrew? then how does it get tightened once the bearing and shaft are in the proper place?

Or does the shaft come out, the bearing get clamped in place, then the shaft gets reinstalled into the now-immobile bearing, thus requiring the more critical adjustments?

I hope the thing stays in one piece over the weekend, as I may not be able to get there until Monday afternoon.

Thanks again.
Aaron

Posted by Steve Guttag (Member # 268) on 03-18-2000, 03:53 PM:

>>"Or does the shaft come out, the bearing get clamped in place, then the
shaft gets reinstalled into the now-immobile bearing, thus requiring the
more critical adjustments?"<<

Pat wasn't kidding about the Vertical shaft being critial in the alignment of the machine and it requiring proper reassembly...so proceed with absolute caution if you haven't done it before.

To properly do it (this presumes you have the time), you will end up having to pull both constant feed assy, the shutter assy and the intermittent assy (DO NOT PULL THE FLYWHEEL AS OTHERS HAVE STATED, this isn't a Century!, the flywheel is an integral part of the intermittent alignment).

Do not be surprised to find the "harp" cracked (aka vertial shaft bracket) where the lower bearing is mounted, the metal gets REAL thin around there and overtighting it WILL crack it and it will be worthless at that point.

Presuming all goes well with tightning the bearing in place, you should be able to properly load the vertical shaft (and bearings before putting it back in the head). Unlike a Century, the Simplex vertical shaft position is only dictated by two parts, the main drive (the one thing you didn't have to remove) and the intermittent. Therefore the intermittent will have to be in place before you tighten the Vertical shaft bracket in place but after you loosley place the bracket. Once you establish the vertical shaft position, the rest of the previously removed components are aligned to it for proper gear mesh.

It would be wise to have a spare set of gaskets for the assemblies you remove to keep everything sealed up tight.

Next week....the proper calibration of FIRE SHUTTERS ;-)

Steve

------------------
"Old projectionists never die, they just changeover!"

Posted by John Pytlak (Member # 331) on 03-20-2000, 09:42 AM:

Pat Moore:

Welcome to Film-Tech Forum! Thanks for following up on my invitation to participate in the FT Forum at ShoWest.

John Pytlak