Carbon Arc ,4k Xenon and Motiograph projector base Issues

[Bobby Hodge]

Hello !

I'm Bobby Hodge, the senior projectionist at the Capitol Theater in Rome NY. Got started at the Riviera Theater in Syracuse NY in 1964.Super Simplex, RCA soundheads and Brenkert Enarc lamps.

I am trying to gather enough correct information relative to the arc lamps at the Capitol theater in Rome NY. Not a simple situation, either so please bear with me.
Bob Throop installed a pair of Ashcraft Cinex lamps that were donated by Avery Fisher Hall in NYC. They burn 11 mm positives. 5/8 ( I think ) negatives.
One lamp has the original design silver water cooled contacts. The other uses a block of stainless steel with a brass insert in each half. There was also another set of well used solid silver contacts that probably came from the lamp with the new stainless.
The problem is with the silver contacts- not with the stainless. There isn't enough adjustment left- eve when using the best combination of silver contacts- to allow the use of the UCAR 11 mm carbons. The manufacturing tolerances are just too sloppy. Yet the SS/Brass contacts work perfectly. No idea who made them. Not that it makes any difference anymore. .
If possible, I'd like to retain the carbon arc lamps which means trying to find several sets of silver or better yet the stainless steel/brass versions.
Another consideration relative to the projector bases and the lamps. They are Motiograph bases and they have a projection / soundhead knuckle that has a vertical positioning adjustment on it which I've never seen on a Simplex base. I tried to adjust this knuckle so that the bolt would clear the bottom of the Cinex, but the knuckle wouldn't budge- it has probably been frozen in that position since the day it was installed. When Bob installed the Cinex lamps, he could only get the lamp house to go as far forward as a bolt that protrudes from this adjustable knuckle, which meant that the lamp probably was not in the correct optical position for our Simplex XL projectors. Since I run variable speed 14- 20 FPS- I know that there is no film damage caused by excessive aperture temp (embossing of print) with the setup I presently have. Even though it is out of alignment, the light is still reasonably acceptable.
The lamps have cutouts for the XL shutters. What worries me is that if I cannot find another set of good contacts and have to go with a 4k Zenon, how much aperture temperature can I expect if I adjust the knuckle so that the lamp houses are in correct optical alignment ? Both Cinexes have dichroic reflectors. The 4k zenon has been recommended for our throw and screen size.

I know I'm asking a great deal, but if I can't find an answer here, then there is no other place to find an answer to it.

[Sam Chavez]

Welcome to our group Bobby. Lot's of questions here. The first thing is to do some research on what the proper working distance actually is between the reflector and the projector aperture. Otherwise you are just guessing. Not all Ashcrafts have the same distance. Core Lite's are different to Cinex or Super Cinex, for one example. As to lamp alignment, there are many ways to get there, washers, metal shims between the lamp table and the bottom of the lamp. There is no one proper way to accomplish this and there was always a lack of precision in our American projector industry.

I'm not the expert on any of this, just was around when these were in use I do know that Boston Light and Sound has made replacement jaws for Strong Excelite and Futura lamps. I saw them in use at the Stanford Theatre in Palo Alto. They were pricey as expected, casting sliver jaws around a copper tube in small quantities.

[Jim Cassedy]

I miss running big carbon arc lamps & motor-generator power supplies. It really separated "the men from the boys", to use a somewhat dated and misogynous phrase.
I remember those water cooled silver-jawed carbon holders. I had a guy ruin one when he was working at the theater on my night off. "The Boss" wasn't too happy having to replace them. I wasn't too happy with The Union for sending someone who should have known better. I've got just one question for you:
☞ Where do you find carbons these days? Is anybody in the US still making them?

Last time was trying to find some, the only sources I found were in China & the USSR, and you had to buy almost a whole pallet-full. Fortunately, I was able to find a guy on e-bay who had a wholebunch of the size I needed that had been sitting in a store-room for years at a recently closed theater. Although they were old, they were still sealed in the factory plastic wrap, so I didn't have any moisture problems.

Good luck with getting your lamphouses aligned & running

[Mark Gulbrandsen]

Charlie Wolk used to keep the silver jaws in a big safe next to his desk. He sold a lot of them!

[Mitchell Dvoskin]

Back when I was involved with the Landmark Loews Jersey we were buying carbons for the Ashcroft Super Cor-Lites from https://www.cinemacarbons.com/index.html .

[Bobby Hodge]

Welcome to our group Bobby. Lot's of questions here. The first thing is to do some research on what the proper working distance actually is between the reflector and the projector aperture. Otherwise you are just guessing. Not all Ashcrafts have the same distance. Core Lite's are different to Cinex or Super Cinex, for one example. As to lamp alignment, there are many ways to get there, washers, metal shims between the lamp table and the bottom of the lamp. There is no one proper way to accomplish this and there was always a lack of precision in our American projector industry.

I'm not the expert on any of this, just was around when these were in use I do know that Boston Light and Sound has made replacement jaws for Strong Excelite and Futura lamps. I saw them in use at the Stanford Theatre in Palo Alto. They were pricey as expected, casting sliver jaws around a copper tube in small quantities.

Thank You, Sam !! I genuinely appreciate your answer. I guess that explains why Motiograph provided that means of adjusting the vertical plane of the projector/ soundhead mount. No shims or washers.But why those darned bolts to impede the positioning of the lamphouse ?
I just sent off a email to Chapin Cutler asking about contacts. I had all but forgotten about BL&S.
A little ancient history. When we premiered Able Gances' " Napoleon" at the Landmark Theatre ( formerly Loews State) in Syracuse, I set up the 3 existing Simplex XL projectors with selsyn motors for the 3 screen finale, Chapin provided the other 2 projectors fof the other single reel projections with changeovers and Xenon lamps. The old Peerless Hy Candescent lamps were replaced with Excelite 135's that were salvaged from the Eckel Theatre- leftovers from the 3 projector Cinerama equipment.
THOSE were the days !!!

I don't recall having to do anything special when aligning those except sliding the lamp forward and back until there reflector met the measurement and cutting a cone for the snout. They fell in alignment like a fine glove. I had the lens plug and string to check it. No Fuss, No Muss Just lucky, I guess.

Very Cordially Yours, Of Course !!

Bobby Hodge

[Bobby Hodge]

Back when I was involved with the Landmark Loews Jersey we were buying carbons for the Ashcroft Super Cor-Lites from https://www.cinemacarbons.com/index.html .

Thank You, Mitchell !! That is well worth keeping track of !
We've been getting NOS UCAR carbons from where ever we could find them Problem with one batch- even though the plastic bags were still sealed - was that a large quantity of another size- larger- packed with the 11 mm. Probably 13 mm and useless as they would not fit in the rotating positive collet.

[Bobby Hodge]

I miss running big carbon arc lamps & motor-generator power supplies. It really separated "the men from the boys", to use a somewhat dated and misogynous phrase.
I remember those water cooled silver-jawed carbon holders. I had a guy ruin one when he was working at the theater on my night off. "The Boss" wasn't too happy having to replace them. I wasn't too happy with The Union for sending someone who should have known better. I've got just one question for you:
☞ Where do you find carbons these days? Is anybody in the US still making them?

Last time was trying to find some, the only sources I found were in China & the USSR, and you had to buy almost a whole pallet-full. Fortunately, I was able to find a guy on e-bay who had a wholebunch of the size I needed that had been sitting in a store-room for years at a recently closed theater. Although they were old, they were still sealed in the factory plastic wrap, so I didn't have any moisture problems.

Good luck with getting your lamphouses aligned & running

I think that if I can find just one more set of stainless steel / brass contacts then the booth will be good to go for a long time. Lord ,and if there is a patron saint for projectionists ,willing !

[John Eickhof]

the trashcan lamps came in several configurations...the s-85 model (ashcraft super high and rca dynarc ) were 80-95a using 10 or 11mm pos with 3/8 neg. working distance was 29 to 30"depending on projector. the core lite was same as s-85 except 35mm only, wd was the same. and was set up for 11mm pos and 5/16 neg for 85-90 amps, and 11/32 for 90-100 amps, the super cinex was a 35/70 lamp wd 31 1/2-32" set up for 13.6 pos and 7/16 neg only operating at 135-165 amps. the super core lite was a 35/70 lamp operating at 135-165 amps with 13.6 pos 7/16 neg. wd 291/2 to 29 3/4". All trashcans had a removeable panel on the front casting to clear the xl shutter housing, all other makes would fit normally, they were not commonly used with motiograph heads as the working distance to clear the barrel shutter was longer, a special reflector for the super core lite was available for motios. as was a special housing for the aa-2 projector.the s-85 and core lite models used a 16" reflector, the super core lite and super cinex used an 18" dia. reflector. have fun!

[Sam Chavez]

John,

Happy to see you are in good form. I knew this thread would smoke you out.

You never call, you never write! What do you know about the adjustable base mount Bobby Hodge mentions?

[Gordon McLeod]

Motiograph had the bull nose mounted on a slide that was locked by 4 bolts that went back towards the base and a large bolt ran downwards that allowed a very accurate lifting of the entire projector and soundhead up and down to align with the lamp. They were a very good base

[Mark Gulbrandsen]

John,

Happy to see you are in good form. I knew this thread would smoke you out.

You never call, you never write! What do you know about the adjustable base mount Bobby Hodge mentions?

Phil Housch said John has been waiting for ink and feathers for going on months now. The next wagon train though Idaho is supposed to deliver them to John....

[John Eickhof]

hi Sam and Mark! Gordon is correct, from the early motio deluxe base (for the H , K, etc), right up through the AA medium deluxe base and the AAA heavy duty base, they kept the same hangar design for the soundhead and retained the original ERPI 'over and under bolt pattern on their soundheads. Somewhere in my RCA service bulletins, there is a section on modifying the trashcan lamphouse to clear the elevation bolt, if I remember correctly, it was only necessary in certain installations where working distance culd not be met, motio lamphouses were made by Strong and the 1kw and the larger 150 amp lamp were designed with mirrors to extend the working distance thus clearing the elevation bolt on motio bases, even the brenkert enarc was available in several working duistances.