Film-Tech Cinema Systems
  Home     Products     Store     Forum     Warehouse     Contact Us    
Film-Tech Forum ARCHIVE


  
my profile | my password | search | faq & rules | forum home
  next oldest topic   next newest topic
» Film-Tech Forum ARCHIVE   » Operations   » Film Handlers' Forum   » Best/worst projector (Page 13)

 
This topic comprises 19 pages: 1  2  3  ...  10  11  12  13  14  15  16  17  18  19   
Author Topic: Best/worst projector
Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

- posted 12-19-2004 07:50 PM      Profile for Mark Gulbrandsen   Email Mark Gulbrandsen   Send New Private Message       Edit/Delete Post 
quote: Steve Guttag
No...it is fact. Gear drive is the most efficient.
Not that I also don't like gear drive... the DP-70 is probably the best example of how efficient gearing can be BUT..... ask any mechanical engineer which is more efficient.... and he will tell you that belts are. Discounting the intermittent which is a separate entity in itself the main reason for needing any oil bath at all is because the gears would wear out quickly without it. Put a belt in an oil bath and it really doesn't matter much, it will last just about as long without the oil. Without oil orthogonal gearing such as in the X-L and DP-70 create heat from the rubbing action... which is definate loss of efficiency by itself in a big way. Timing belts don't have this problem, there is almost zero rubbing action with timing belts and they can tolerate heat very well... they are even more efficient than chains... one of the main reasons that Harley Davidson now sells just about every bike with timing belt final drive.

I completely agree with you on the Century movement!! We make tons of money on both Simplex and Century movement failures over the course of a year. Its been over two years since an Ultramittent has failed.

Mark

 |  IP: Logged
Monte L Fullmer
Film God

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

- posted 12-19-2004 07:55 PM      Profile for Monte L Fullmer   Email Monte L Fullmer   Send New Private Message       Edit/Delete Post 
Being the projection field too many years, and have seen both -the belts and the oil/wet gear drives, I can see why lately the desire for oil bath types are more desireable-less site maintenance, thus the need for less service calls, since the new way of running cinemas with the useage of high-school/unprofessional employees who don't give a hoot about their job, just do the job and no skills taught in maintenance, and management don't want to worry on such technical matters only when needed to call the area "tekkie" to come and fix their problems. In otherwords, a "machine" operation-no skills, no training, no logical understanding of the operation, just "robots"-being told what to do.

Can you imagine on showing "robots" on how to do belt changes in the Christie 35/P35GPS/CineX-35 units, let alone the manager, who doesn't even want to open up the back of one of these machines and to try to figure out how to do it, and being taught how, for he figures that he's more important than doing "tekkie" work?

Oil changes are actually nothing. And even then, some of these cinemas will let their Simplexes run dry, burn up intermittent assemblies, trash gears, etc, and they wonder why it crashed on them since they were never shown in the first place, or took over the cinema without a clue on what to do.

I know where Marko is coming from - from the quality standpoint of the "trade"-where there were actual, professional projectionists taking care of all of this equipment.

And I see where the others are coming from as well for the oil bath machinery - some for the employee/personnel part: they're in the KISS format (Keeping It Simple, STUPID..) that the machine will run forever with very little effort in maintenance. These kind of compainies expect the "tekkie" to do all the work needed and come in a holler's notice, and if the service work is completed when they leave, and something breaks down, who do the managers/owner blame?...they blame the "tekkies", since the "tekkies" know everything and know how to make things work correctly.

A somewhat sad trend in the presentation department of this industry. - thx Monte

 |  IP: Logged
Steve Guttag
We forgot the crackers Gromit!!!

Posts: 12814
From: Annapolis, MD
Registered: Dec 1999

- posted 12-19-2004 08:16 PM      Profile for Steve Guttag   Email Steve Guttag   Send New Private Message       Edit/Delete Post 
Its not like I haven't had some Mechanical Engineering training, ya know. Yes, the gear does need lubricant (just like bearings and such)...that is part of the system...if properly lubricated, and the gear system is well designed...their life span is quite long.

As to belts they introduce elasticity to the system, which takes away from efficentcy. Part of the energy goes into stretching the belt and then you set up a harmonic. The system is a bit more controllable with just two points...typically in a projector a belt that drive sprockets is hitting 3 or more pullies that each have their harmonics. Take a strobe to the belt and you can see the thing moving forward and back...take a look at the sprockets driven by a belt...they often are not turning smoothly with respect to each other. I don't doubt the new Christie got a big improvement by using the same sprocket on either side of the sound head. With two sprockets driven off the same belt they are going to beat against each other and set up a jitter.

Listen to most any belt drive machine without the film threaded...you can hear the period of the belt as it works its way around. Then you throw the bearings into the mix...depending on environment...typical bearings will rust out on you in the Mid Atlantic area with the cycle of humid/dry seasons. How many projectors that run on ball bearings for their various shafts have them last very long? Compare that to a bronze bearing with oil delivery.

BTW Monte, my preference for oil bath machines are not just on the decrease in maintenence...I like the Simplex machine. Not that it is perfect but on the whole...it has done me and many others well over the years. Call it a preference if you want, but I prefer the Simplex over the Century or Christie. I've NEVER been a fan of the 5-star soundhead though...it has a poor belt path design that improperly loads the sprocket shaft outboard of bearing support (66-tooth pulley should not be the last thing on that shaft...another bearing to support the shaft would have save many many shaft and bearing failures. I prefer the gearbox soundheads. The Apogee does that one better in that now it is just one big happy oil sump rather than two with different oil grades. Too bad they don't plan to make it in a single lens version to suppor the types of theatres we typically install (screening rooms with 4-5 picture formats).

Steve

 |  IP: Logged
Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

- posted 12-19-2004 08:47 PM      Profile for Mark Gulbrandsen   Email Mark Gulbrandsen   Send New Private Message       Edit/Delete Post 
Steve,

Elasticity is not much of a factor in a properly designed belt driven system, but in an overloaded system it can be a huge factor. Some elasticity could also be a good thing and take up unwanted shock. Modern Kevlar timing belts really don't stretch at all!!

The harmonic problem is more true of square tooth belts but not really a factor with round tooth belts. But it is even more of a factor with double sided belts which is where the 35GP flitter problem lays!! Harmonics are also a factor in gearing but to a lessser degree. The harmonic problem is one reason they changed(as Strong did)to the round tooth belts. Although I can't exactly remember I also believe that each sprocket has its own belt now but I would have to look at one of the new machines again to see. The proof that it works and works well is in the SRD error rate which is now in the 1's and 2's with the basement reader.... thats dam low error rate for any basement reader

Mark

 |  IP: Logged
Monte L Fullmer
Film God

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

- posted 12-19-2004 09:11 PM      Profile for Monte L Fullmer   Email Monte L Fullmer   Send New Private Message       Edit/Delete Post 
True. I DO miss the old SH-1000,"4-star" head. These heads would neve die, but as always, have to keep an eye on the oil level and oil changing frequency in that transmission due to the brass sprocket gears being driven by the steel worm motor gear.

The "5-star", to me, was a letdown from Simplex, even though of the more simplicity and compactness in design. Just too bad that they didn't find a way to gear drive that head as well, just to keep the quality at the highest.

I also miss Motiographs "AA's" - built like a tank. Just that the Mirrorphonic soundhead needed that flywheel on the motor so the machine didn't start up so jack-rabbit quick-to start up smoothly as of the SH-1000.

One can say comparing "Apples to Oranges", "Chevys and Cadillacs", "Blondes and Brunettes", et.al. .. who gonna win and who's gonna lose? NOBODY! ALL are winners in each of the individual's eyes.

Then, we all must be winners in this facinating world of the presentation trade to stay in it this long. Otherwise, we all wouldn't be here. We'd be off doing something else.

thx-Monte

 |  IP: Logged
Sam D. Chavez
Film God

Posts: 2153
From: Martinez, CA USA
Registered: Aug 2003

- posted 12-19-2004 11:21 PM      Profile for Sam D. Chavez   Author's Homepage     Send New Private Message       Edit/Delete Post 
I've been watching the banter between two very good friends about Christie vs. Simplex with some interest.

I'm a bit amazed at Mark's faith in the new Christie design after the continual changing of this machine since 1980.

It's Ultramittent is one of those ideas that looked good on paper but it has never proven to be any better than an ordinary movement.

Some healthy skepticism might be in order here.

When it comes to projectors, the proof of the pudding is in the eating. I've seen any number of XL's with over 30 years on them and nary a part change besides sprockets.

The intermittent parts are indeed small but this is a very happy projector that does not beat itself to death.

I agree they have a number of faults but the basic design is very sound, and Strong kept the best of it intact in the design of the Apogee.

To paraphrase Patrick Moynihan, we are all entitled to our own opinions, but not our own facts.

The Simplex has proven to be the industry work horse for longer than most of has been alive. The basic reason is you start with a good design and build on it.

A similar concept is the Chevy V8 engine that has been around since 1955. It has been developed, enhanced, reworked and improved constantly ever since. This is no accident. It was a great design and people keep finding ways to get a bit more performance out of this venerable work horse.

Meanwhile, you don't see that with any other engine of that era. Why?

 |  IP: Logged
Steve Kraus
Film God

Posts: 4094
From: Chicago, IL, USA
Registered: May 2000

- posted 12-20-2004 12:02 AM      Profile for Steve Kraus     Send New Private Message       Edit/Delete Post 
Refresh my memory what the great innovation of the Ultramittent was/is. An ordinary intermittent with seals?

 |  IP: Logged
Monte L Fullmer
Film God

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

- posted 12-20-2004 04:55 AM      Profile for Monte L Fullmer   Email Monte L Fullmer   Send New Private Message       Edit/Delete Post 
What's funny about the Ultramittent, is that this unit design reminds me of the way the old Simplex-Standard/Super/E-7 assemblies were designed, outside of the usage for the taper pins of the Super. -Monte

 |  IP: Logged
Steve Guttag
We forgot the crackers Gromit!!!

Posts: 12814
From: Annapolis, MD
Registered: Dec 1999

- posted 12-20-2004 06:57 AM      Profile for Steve Guttag   Email Steve Guttag   Send New Private Message       Edit/Delete Post 
Not that I'm a car buff or anything...but Sam...when did the Crysler Slant-6 come into existance? Oil is optional on that baby....but yes the Chevy 350 is one of those that seem to have had devine intervention.

Steve

 |  IP: Logged
Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

- posted 12-20-2004 07:28 PM      Profile for Mark Gulbrandsen   Email Mark Gulbrandsen   Send New Private Message       Edit/Delete Post 
quote: Sam D. Chavez
I'm a bit amazed at Mark's faith in the new Christie design after the continual changing of this machine since 1980.
Continual changes are not what bothers me. Its when there is a problem and its not dealt with. While the machine has gone through more changes than anyone in North America could remember the thing that I notice is that what ever version you run into they are still putting out dam good pictures. Even the straight gate machines performed admirable and had a very well designed pressure pad system.... much better then todays straight gate X-L pads that wear very unevenly. The Christies wear very even and in some ways the straight gate performs better than the curved gate does. I have alot of faith in the new projector because it went through considerable field testing before it was released.

quote: Sam D. Chavez
When it comes to projectors, the proof of the pudding is in the eating. I've seen any number of XL's with over 30 years on them and nary a part change besides sprockets.
Yes Sam you hit the nail on the head! You need to find a 30 year old machine to get one that has decent quality stars, cams and other important metal parts. Todays CNC manufacturing world does not allow the use of steel that is nearly as high of grade as was being used when those parts were all hand made. Better steel is harder on tooling and slows down production, just the inverse of why there is CNC in the first place. In fact today the only hand done step in those critical parts is done when the final grind is done on the slot. The metals used are no where near as hard nor are they hardened to the Rockewell spec that the old parts were. Believe me, I've measured them myself with a Rockwell hardmess tester and they are simply not the quality of yesteryears stuff. Personally I'd rather keep the good intermittent parts and keep the crappy main casting if there were a choice today

Another thing to consider is that LaVezzi rates the life span of the movement parts at 5 years assuming 8 hour days and so on. I was told this by Al himself. The thing that helps the Ultramittent outlive many other movements is the synthetic brew its filled with. The same long service can be had from the Century movement if you use the same oil... Its too heavy for the X-L but there are other good synthetics that can help extend the life span past 5 years.... but few use them. This is one thing Strong may ultimately change on the Apogee. I hope they do.

quote: Mark Gulbrandsen was the last to post
Meanwhile, you don't see that with any other engine of that era. Why?
Actually there were several other engines of the era that were also bullett proof. The 292 Chevy 6, 283, 327, and the Chrysler 318 were every bit as reliable as the 350 was, the 318 perhaps even more so then the 350! Ford... at least they were First On Race Day probably only because the 390 was also as great an engine.

quote: Steve Kraus
Refresh my memory what the great innovation of the Ultramittent was/is. An ordinary intermittent with seals?
A permanently sealed all ball bearing intermittent. Yes even its gone through changes for the better in which the star and cam inside ball bearings were replaced with bronze bushings. Both outer ball bearings were retained. While older movements may occasionally fail its very rare for the later style to actually fail. About the only thing that fails is one or both of the outer ball bearings. Slap in new bearings and keep on goin. Some of these movements have been running in excess of 10 years and thats darn good service if you base it on the 5 year average life that LaVezzi told me. Did it deserve an Oscar.... probably not because its internals are definately nothing at all new in the least. Motiograph used ball bearings for both outers in its movements as well. LAVezzi should have receivd an Oscar for the VKF sprocket design way before the Ultramittent was considered. The VKF stuff has greatly contributed to decreasing film damage more than almost any other thing I can think of.

Mark

 |  IP: Logged
Sam D. Chavez
Film God

Posts: 2153
From: Martinez, CA USA
Registered: Aug 2003

- posted 12-20-2004 09:00 PM      Profile for Sam D. Chavez   Author's Homepage     Send New Private Message       Edit/Delete Post 
Mark,

I would say you are missing my point on the Dodge and Ford engines. Bulletproof is not the order of the day, adaptability to future uses are the issues (The Ford engine you mentioned came from the 352 and was only competitive for one season). The Chevy 265, 283 and 327 ware all earlier adaptations of the 350.

I'll bet there is not even one interchangeable part from the first Christie to the present version apart from the sprockets and the screws.

While we are at this, why does every Christie sound head have a broken air pot?

 |  IP: Logged
Steve Guttag
We forgot the crackers Gromit!!!

Posts: 12814
From: Annapolis, MD
Registered: Dec 1999

- posted 12-21-2004 07:51 AM      Profile for Steve Guttag   Email Steve Guttag   Send New Private Message       Edit/Delete Post 
quote: Mark Gulbrandsen
Slap in new bearings and keep on goin. Some of these movements have been running in excess of 10 years and thats darn good service if you base it on the 5 year average life that LaVezzi told me.
That may be what Al told you but I can't verify that from the field...With reasonable oil changes...they are going way beyond 5 or 10-years.

When Poly first hit...we were getting an awful lot ot dusting into the outer bearing that would try to sieze them but that isn't much of an issue anymore (note we even put an oil hole on the outter bearing but that just allow the dust turn to goo.

The company I used to work for (back in the 80s) had Christie and Simplexes...the Simplexes consistantly were steadier, more reliable, better supported and MUCH MUCH more longer lasting to the point all of the Christies were eventually retired for Simplexes and I mean ZERO of them survive to this day. When Century moved to Strong...one prominate chain went to Christie to avoid the Strong connection...that didn't last either...they are back to Century.

When it comes to movie projectors...you show me belts and ball bearings...I'll show you more service calls, maintenence.

Then again, I'm not a fan of slapping grease onto spinning gears either...too many main-drive, shutter and intermittent drive gear changes. The fault there isn't the gear, persay...it is the lubrication delivery system (there isn't any) and the rather rough loading of the system.

About the only thing I costantly like about the Christie is their precision. Things line up, consistantly...the film path doesn't skew...their machining is top notch. Ya know, if they had an oil bath on the backside (and nix the belts) they'd have a nice machine.

Steve

 |  IP: Logged
Gordon McLeod
Film God

Posts: 9532
From: Toronto Ontario Canada
Registered: Jun 99

- posted 12-21-2004 10:05 AM      Profile for Gordon McLeod   Email Gordon McLeod   Send New Private Message       Edit/Delete Post 
I guess I should interject finally I actually agree with Mark on the belt issue We service lots of vic5's ernemanns and if the timeing belt is replaced yearly then there is no issues with them
Also the Vic5 has very low flutter or digital jitter
And I agree with steve (this is a red letter day) on the issue of the poor lubicration system on century gears

 |  IP: Logged
Richard Fowler
Film God

Posts: 2392
From: Ft. Lauderdale, FL, USA
Registered: Jun 2001

- posted 12-21-2004 12:06 PM      Profile for Richard Fowler   Email Richard Fowler   Send New Private Message       Edit/Delete Post 
Remember the grease pump for Century projector that Kelmar designed for U. A. Cinemas....the device looked like a refugee from a porno shop [Big Grin] ; it did address the issue of trapping grease around the main drive gear, which was always poorly lubricated. The belt idler does suck on the Ernemann; we made our own units with a flanged timing gear of a larger diameter....no problems so far.

 |  IP: Logged
John Hawkinson
Film God

Posts: 2273
From: Cambridge, MA, USA
Registered: Feb 2002

- posted 12-21-2004 01:44 PM      Profile for John Hawkinson   Email John Hawkinson   Send New Private Message       Edit/Delete Post 
You know, "just replace the belt yearly," seems like a lot to ask when there are other projectors that will just keep trucking with only lubrication-based maintenance.

--jhawk

 |  IP: Logged


All times are Central (GMT -6:00)
This topic comprises 19 pages: 1  2  3  ...  10  11  12  13  14  15  16  17  18  19   
   Close Topic    Move Topic    Delete Topic    next oldest topic   next newest topic
- Printer-friendly view of this topic
Hop To:



Powered by Infopop Corporation
UBB.classicTM 6.3.1.2

The Film-Tech Forums are designed for various members related to the cinema industry to express their opinions, viewpoints and testimonials on various products, services and events based upon speculation, personal knowledge and factual information through use, therefore all views represented here allow no liability upon the publishers of this web site and the owners of said views assume no liability for any ill will resulting from these postings. The posts made here are for educational as well as entertainment purposes and as such anyone viewing this portion of the website must accept these views as statements of the author of that opinion and agrees to release the authors from any and all liability.

© 1999-2020 Film-Tech Cinema Systems, LLC. All rights reserved.