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Topic: Loud Century Intermittent

Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 06-11-2005 03:01 PM

quote: Dominic Espinosa
Something I've been wondering about...
Is there anything recommended for flushing these besides oil?

We probably get three to four of these a week at CLACO. NO!... Don't flush a movement out. All you will do is loosen up more gunk and cause faster wear of the parts inside. Have the movement torn down, cleaned, and inspected to see whats really wrong.... it may only need a new cam pin or just a cam pin and star. BTW: Movements should really be dismantled, ultrasonically cleaned then then inspected.

I reccomend adding a tiny disk magnet inside a rebuilt movement to attract metal particles that will cause faster wear and switching to LAVezzi oil is also a great idea and will drastically extend a new or rebuilt movements life span. It may even quiet a noisy one down a bit but there is still wear in there that will need to be taken care of Sooner than Later.

Mark

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 06-11-2005 03:53 PM

Yo Mark - any buzz on that "loaner" SA intermittent that you had planned on sending me for the Terrace?

I looked in the sight glass on this thing and the oil is definite need of changing-pretty dark. Yet, interestingly that the movement had quieted down for some reason-doesn't "clunk-clunk-clunk" anymore on startup. Any clues?

thx-Monte

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 06-11-2005 05:52 PM

Its hard to say Monte, possibly dried oil in the oil spirals, running it a while will sometimes dissolve that. Will send the loaner movement out Monday if you think you still need it, thought you were going to be on vacation so didn't send it last week. Anyway call and let me know Monday morning. BTW: Using LaVezzi synthetic is a good idea as oil will not evaporate on the spirals.... synthetic oil does not evaporate.

Mark

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Randy Bowden
Expert Film Handler

Posts: 146
From: Portland, OR, USA
Registered: Aug 2000

posted 06-14-2005 05:28 PM

I do consider myself a bit of an expert of this subject(I've rebuilt well over a thousand intermittents)...So aside from the possibility that your flywheel came loose as mentioned previously. The ONLY way to quiet down that intermittent is to have it rebuilt, if it was run dry the cam pin does indeed have flat spots, the bushings are also likely worn down, that also adds to the noise factor. 9 times out of 10 I replace the bushings on a century rebuild and I don't bother with crappy mod that Strong made by adding oil seals to the intermittent. Talk about a stupid thing to do. Shortening the bushing to add an oil seal only shortens the life of the bushing, thus making the intermittent wear out faster. The long spiral non seal bushings that Lavezzi sells work the best, they last the longest and DO NOT LEAK! Sorry to get off track but it feels good to vent sometimes.

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 06-14-2005 07:04 PM

quote:
Shortening the bushing to add an oil seal only shortens the life of the bushing, thus making the intermittent wear out faster. The long spiral non seal bushings that Lavezzi sells work the best, they last the longest and DO NOT LEAK!

Er, ah Randy, Its actually desriable for a bushing to seep just a very teenie-tiny bit of oil. This is perfectly normal and is actually desriable. You can find info on this in any engineering type refrence book. Brand new Simplex movements always exhibit this as should any properly rebuilt movement. If it does not then the bushing was not lapped out correctly, clearance is too tight, and the shaft and bushing are not getting enough oil cushion along its full length. A bushings bore should ALWAYS be checked with a hole gauge to be sure that there is just enough clearance for the weight of oil being used. Lack of a tiny bit of seepage can lead to a seize up on a hot running machine or just plain premature wear. I somewhat agree with you on the bushing thing but if you do the calculations you'll find that the shorter bushings are only about 14.6% shy of the originals actual bearing surface.... not enough to matter much. I did these calculations years back when I built my VistaVision movements as I needed to use the seals to keep the oil inside the movement! The VV movement that has seen the most service still runs perfect almost 12 years later.

quote: Randy Bowden
I replace the bushings on a century rebuild and I don't bother with crappy mod that Strong made by adding oil seals to the intermittent.

Don't blame Strong for that, it was an ORC thing they inherited and works just fine and as designed over the life of the seals.

Todays pisser is the poor overall quality of intermittant parts that are made.... not even close to the quality of stuff made in years past, all because they need to be produced by CNC to turn a profit(maybe). Check them for your self some time with a Rockwell hardness tester... the older parts are generally pretty amazing quality compared to todays stuff, even todays cast iron is crap compared to stuff made years ago, thank the EPA for that change. You'll find the best made stars and cams are those that were made by Phillips back in the 50's and 60's, they just don't wear out if the oil is properly maintained. Sad that all the artists of yesteryear are all dead.

Mark @ CLACO

BTW: I'm well over 1000+ movements ahead of ya.....

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Randy Bowden
Expert Film Handler

Posts: 146
From: Portland, OR, USA
Registered: Aug 2000

posted 06-14-2005 07:22 PM

WOW...now I remember why I don't post on here anymore...you know everything.

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Marc Hansen
Film Handler

Posts: 93
From: Seattle, WA, USA
Registered: Dec 2000

posted 06-14-2005 09:04 PM

quote: Mark Gulbrandsen
A bushings bore should ALWAYS be checked with a hole gauge to be sure that there is just enough clearance for the weight of oil being used.

Mark - How much clearance would you run?

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 06-15-2005 12:36 AM

quote: Randy Bowden
WOW...now I remember why I don't post on here anymore...you know everything.

Hardly Randy, but I did at least do some research and talked to the folks that make the parts back when I built the VV movements as to the proper clearance rquired.

quote: Marc Hansen
Mark - How much clearance would you run?

Mark,

Now you're a machinist and you should know the basics..... The Bushings in the Vista movements have about .0005 oil clearance for 20 weight synthetic(LaVezzi Oil) to start with. This clearance was actually reccomended by none other than Al LaVezzi himself. I had arrived at just slightly less than that using formulas provided by friends that design machnery and also from Machinery's Handbook. After run in this of course increases again just slightly.

BTW: Yes, I do own a set of hole gauges just in the sizes I use in Movements and a full set of gauge blocks. No, I don't ALWAYS use the hole gauges in every day movement repair/rebuild...... they're too expensive. But its how I would teach someone to do it. I use the gauge blocks to double check calibration on my mics and calipers and for making other odd measurements. Also, through the use of the hole gauges it makes it alot easier for someone new to learn how to judge fit by how it feels. I've also been through LaVezzi's plant a number of times and have seen their people using hole gauges to check the specs of bores on new bushings. In the last trip they had switched to a more modern video tolerance checking system that was pretty cool.

Mark

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Michael Schaffer
"Where is the
Boardwalk Hotel?"

Posts: 4143
From: Boston, MA
Registered: Apr 2002

posted 06-15-2005 03:38 AM

quote: Mark Gulbrandsen
You'll find the best made stars and cams are those that were made by Phillips back in the 50's and 60's, they just don't wear out if the oil is properly maintained. Sad that all the artists of yesteryear are all dead.

Maybe not all of them. Kinoton intermittents are still built in-house by master craftsmen, and if you know what it takes to get a master craftsman's certification in Germany (where the equivalents of "bachelor" and "master" are not university degrees, but strictly controlled craftsman's titles) then it is easy to understand why there are so few problems with these intermittents. There may be the odd bad egg too, but generally, these intermittents give you very little trouble and a very steady picture for many, many years.

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 06-15-2005 09:02 AM

Michael,

I've never had to replace a Kinoton movement or a Phillips for that matter, just tear down, inspect, and clean up. I've only had to replace seals or couplings on FP-20 type movements. I've replaced a few old style fibre drunken cams in early portable Phillips 16's and FP-16's though. I was primarily referring to movement parts that I have actually measured the hardness on, mainly U.S. made parts and I happened to own a DP-70 at that time and the hardness of those parts surpassed everything else I had brought to measure, alot of it also has to do with the quality of the steel being used. So yes, it seems that all U.S. craftsman are long gone but its nice that Kinoton still have a few left.

Mark

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Marc Hansen
Film Handler

Posts: 93
From: Seattle, WA, USA
Registered: Dec 2000

posted 06-15-2005 10:00 AM

Thanks Mark Thats the area I was thinking (3-5 tenths). I have honing equipment & bore gauges so it's easy to hit a tenth.

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 06-15-2005 11:50 AM

Yea, Thats actually what the factory recommends. You can't generally hit that by just the hone and feel method but with alot of practice one can get pretty close to that. I wanted to keep the VV movement bushings tight and to spec so as much oil would stay in the star wheel sprial as was possible with the movement in the vertical position. This way when it would sit overnight the oil won't completely drain back down from the bushings and cause accelerated wear to those parts ever day it was re-started. I wanted to just have to make these movements one time and forget about them except for occasional oil changes.

P.S. I wish I had a real honning machine.... [thumbsup]

, I just work with regular barrel laps [Eek!]

.

Mark

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