1946 Ampro Premier 10 Projector - UK Vintage Radio Repair and Restoration Discussion Forum

PJL · 1st Oct 2008, 10:39 am

I was given this projector along with a collection of 16mm films. This is not really my thing but the forty or so largely Castle b/w short films had me curious. The projector had not been stored too well and had an over-powering smell of mildew. Externally the cabinet fixings and screws were showing some rust and inside there were white mildew deposits but fortunately the projector itself still looked OK. As well as the films, it came complete with the instruction manual, warranty card and service kit but did have a missing photocell for which a replacement was ordered from the USA via Ebay.

The Premier 10 was not sold in the UK and this one was imported and came with a large vintage auto-transformer to supply 115V from 230V. I opted to run the autotransformer on the opposite split to reduce the 240V to 110V as a 1% overvoltage on the lamp can reduce the 25hr life by 12%

.

I tackled the 6V6GT PP amplifier first. It had been professionally maintained in the past and had a fair number of TCC replacement capacitors and what I suspect is an official replacement PP driver transformer. I replaced all paper capacitors, powered it up on a lamp limiter and variac and it slowly came back to life. At about 90V AC the exciter lamp kicked in and checking against the user manual, all voltages seemed about right (if you can call 400V anode potential on a 6V6GT ‘right’).

A rare sunny day had me washing out the cabinets to remove the stench. The speaker metal grill had been painted with a mottled brown flock finish which was falling off revealing some surface rust. Taking it apart revealed further problems as the cloth was stuck to the finish and had either been painted or had absorbed the black stain applied to the internal wood surface. Only option was to paint the grill with a primer and a dark brown finish.

Mechanical condition was quite good with nothing obviously missing or badly worn. However, the entire mechanism was covered in oil, dust and debris and needed a spring clean so I stripped it down and washed it in white spirit. A couple of points worth noting, I had to prize out compressed deposits between the paxolin gear teeth to get the action completely free and I took particular care to flush out the oil ways as the projector runs hot and relies on a regular supply of oil from a central reservoir. Otherwise it was just a case of fresh oil and grease to the motor bearings.

The installed lamp was a 1000W type and close inspection revealed a hairline crack so I didn’t fancy trying it but Ebay USA came up trumps again. Running it up was a bit scary as the hefty mechanics whistle round at a fair pace and I was half expecting the delicate film to be shredded. Once I was confident it was OK I ran through a couple of the films including ‘Chimps last chance’, a silent with piano sound track in which a chimp rolls and smokes a cigarette

…great fun. One or two of the films have got vinegar disease but most look OK.

It took a fair few hours to get this into reasonable working condition and I still have some tidying to do on the cabinets but it’s a great piece of nostalgia and should give a few hours non-PC family entertainment. If I get the time I'll post a video on YouTube.

PS: I hope this isn't OT for a vintage wireless forum but I thought it might be of interest.

kalee20 · 1st Oct 2008, 12:59 pm

Projectors like this are really triumphs of miniaturisation over good design practice - the idea of 6V6's generating their own heat, cramped in a small cabinet, together with to a 1000W lamp, with steady vibration from the motor, really doesn't fill me with nthusiasm!Having said that, the Ampro designers really didn't have much other choice if the brief was to produce a self-contained 16mm portable unit. So, credit where it lies. Good on you for getting it running!

I'm interested in the 'vinegar disease' you mention in a couple of the films. Generally this is decomposition of the cellulose nitrate base material of film, during which process the film turns from highly inflammable, to spontaneously combustible. However, to my (fairly certain) kinowledge, 16mm film was never made with a nitrate base - it was always 'safety' film (originally cellulose acetate and these days polyester or polypropylene). Do you have any small scraps you could test for flammability? I'd be really interested in the result!

Optical sound recording, if well stored, has amazing longevity - much better than magnetic tape as there's no susceptibility to magnetic fields, print-through etc. As long as the film isn't scratched, it's capable of sounding as good as it did when new.

batterymaker1 · 1st Oct 2008, 1:05 pm

Great restoration. Reminds me when I restored my wife's grandfather's Revere 16mm projector. It was a treat to play films she and her brother hadn't seen in over twenty years.

ppppenguin · 1st Oct 2008, 2:00 pm

Vinegar syndrome can definitely occur with safety film. It's not hard to imagine cellulose acetate being converted into acetic acid.

http://www.brucecowellphotographer.c...%20Feature.htm

AFAIK, all sub-standard film (ie below 35mm) used a safety base.

PJL · 1st Oct 2008, 3:42 pm

This is built and weighs like a tank so no rattling! The fan is the main noise contributer and the turret would make a good hair dryer. The amp is compact and it is interesting the switching prevents the lamp on without the fan but does allow the amp.

After an initial panic I also read on wikepedia that 16mm films were all safety film. The disease appears to be confined to a set of copies of a play made in germany which are stored in cans. They have a distinct acetic acid smell and are shrivelled - I might try setting a match to a (very) small piece before I dispose of it.

I am running a 120-125V lamp at 105-110V to preserve it but because it has a long throw lens the image across a normal room isn't that big and is more than bright enough.

Without the films I really wouldn't have bothered with this restoration but I am now very pleased with the results. Although the films date from the late 40's to the early 50's many are copies of early pre-war films and as they would fail broadcasting standards I guess this is about the only way you are ever likely to see them.

chipp1968 · 1st Oct 2008, 5:53 pm

Very nice machine .
I was given two prjectors without sound recently . same make. one from 59/60 other was 70s . the older machine is very attractive and well made .

PJL · 1st Oct 2008, 9:07 pm

Tried burning the vinegar film and it will not sustain a flame no matter how hard you try...so no fun there.

Chipp1968 - did you get any films with yours?

ppppenguin · 1st Oct 2008, 9:10 pm

Just make sure you keep the vinegar film well away from any others. Apparently vinegar syndrome is contagious.

chipp1968 · 2nd Oct 2008, 8:53 am

Quote:

Originally Posted by PJL

Tried burning the vinegar film and it will not sustain a flame no matter how hard you try...so no fun there.

Chipp1968 - did you get any films with yours?

Yes but cant say what they were

very dated I have to say.
I have some old family ones that should work on them though
Mine are Eumig , just in case that wasnt clear . The 70s one is working ,I actually lent it to Drwho for something he wanted to see ,but the nicer one i havnt tred as its missing the power lead

kalee20 · 2nd Oct 2008, 12:47 pm

Jeffrey ppppenguin wrote:

Quote:

Vinegar syndrome can definitely occur with safety film. It's not hard to imagine cellulose acetate being converted into acetic acid.

I agree - I didn't know it actually happened though. I've learned something, thanks! Does it also happen with the acetate recording tapes I wonder?

Thanks also PJL for the flame test. That's behaving as it should for safety film.

Back to the projector - as it allows the amplifier on without the motor and lamp, does it have an auxiliary input for microphone or record deck (non-sync in projectionist-speak)? If so, what's the quality like?

ppppenguin · 2nd Oct 2008, 1:45 pm

Acetate tape ought to be equally vulnerable to vinegar syndrome though I've not heard about it.

Nitrate film doesn't produce acetic acid but can produce nitric acid. Still a nasty smell but rather different to vinegar.

PJL: Congratulations on an excellent restoration.

PJL · 2nd Oct 2008, 8:15 pm

Audio quality is not exactly hi-fi at the moment but maybe it never was. I've fiddled around to refocus the audio optics and realigned the film and managed to get more HF but it remains quite distorted.

Kalee20, it does have a mic input with seperate volume so I think I'll try a CD player next as it's possible the output valves are badly matched. The PM speaker is a bit of an antique too and at the mo its out of the cabinet as I'm still sorting out the grill.

Think I best order a few spare lamps as I'm getting addicted...

1st Oct 2008, 10:39 am	#1
PJL Dekatron Join Date: Sep 2005 Location: Seaford, East Sussex, UK. Posts: 5,997	1946 Ampro Premier 10 Projector I was given this projector along with a collection of 16mm films. This is not really my thing but the forty or so largely Castle b/w short films had me curious. The projector had not been stored too well and had an over-powering smell of mildew. Externally the cabinet fixings and screws were showing some rust and inside there were white mildew deposits but fortunately the projector itself still looked OK. As well as the films, it came complete with the instruction manual, warranty card and service kit but did have a missing photocell for which a replacement was ordered from the USA via Ebay. The Premier 10 was not sold in the UK and this one was imported and came with a large vintage auto-transformer to supply 115V from 230V. I opted to run the autotransformer on the opposite split to reduce the 240V to 110V as a 1% overvoltage on the lamp can reduce the 25hr life by 12% . I tackled the 6V6GT PP amplifier first. It had been professionally maintained in the past and had a fair number of TCC replacement capacitors and what I suspect is an official replacement PP driver transformer. I replaced all paper capacitors, powered it up on a lamp limiter and variac and it slowly came back to life. At about 90V AC the exciter lamp kicked in and checking against the user manual, all voltages seemed about right (if you can call 400V anode potential on a 6V6GT ‘right’). A rare sunny day had me washing out the cabinets to remove the stench. The speaker metal grill had been painted with a mottled brown flock finish which was falling off revealing some surface rust. Taking it apart revealed further problems as the cloth was stuck to the finish and had either been painted or had absorbed the black stain applied to the internal wood surface. Only option was to paint the grill with a primer and a dark brown finish. Mechanical condition was quite good with nothing obviously missing or badly worn. However, the entire mechanism was covered in oil, dust and debris and needed a spring clean so I stripped it down and washed it in white spirit. A couple of points worth noting, I had to prize out compressed deposits between the paxolin gear teeth to get the action completely free and I took particular care to flush out the oil ways as the projector runs hot and relies on a regular supply of oil from a central reservoir. Otherwise it was just a case of fresh oil and grease to the motor bearings. The installed lamp was a 1000W type and close inspection revealed a hairline crack so I didn’t fancy trying it but Ebay USA came up trumps again. Running it up was a bit scary as the hefty mechanics whistle round at a fair pace and I was half expecting the delicate film to be shredded. Once I was confident it was OK I ran through a couple of the films including ‘Chimps last chance’, a silent with piano sound track in which a chimp rolls and smokes a cigarette …great fun. One or two of the films have got vinegar disease but most look OK. It took a fair few hours to get this into reasonable working condition and I still have some tidying to do on the cabinets but it’s a great piece of nostalgia and should give a few hours non-PC family entertainment. If I get the time I'll post a video on YouTube. PS: I hope this isn't OT for a vintage wireless forum but I thought it might be of interest. Attached Thumbnails Last edited by PJL; 1st Oct 2008 at 10:52 am.

1st Oct 2008, 12:59 pm	#2
kalee20 Dekatron Join Date: Feb 2007 Location: Lynton, N. Devon, UK. Posts: 7,078	Re: 1946 Ampro Premier 10 Projector Projectors like this are really triumphs of miniaturisation over good design practice - the idea of 6V6's generating their own heat, cramped in a small cabinet, together with to a 1000W lamp, with steady vibration from the motor, really doesn't fill me with nthusiasm!Having said that, the Ampro designers really didn't have much other choice if the brief was to produce a self-contained 16mm portable unit. So, credit where it lies. Good on you for getting it running! I'm interested in the 'vinegar disease' you mention in a couple of the films. Generally this is decomposition of the cellulose nitrate base material of film, during which process the film turns from highly inflammable, to spontaneously combustible. However, to my (fairly certain) kinowledge, 16mm film was never made with a nitrate base - it was always 'safety' film (originally cellulose acetate and these days polyester or polypropylene). Do you have any small scraps you could test for flammability? I'd be really interested in the result! Optical sound recording, if well stored, has amazing longevity - much better than magnetic tape as there's no susceptibility to magnetic fields, print-through etc. As long as the film isn't scratched, it's capable of sounding as good as it did when new.

1st Oct 2008, 1:05 pm	#3
batterymaker1 Heptode Join Date: Apr 2006 Location: Indianapolis, Indiana, USA. Posts: 674	Re: 1946 Ampro Premier 10 Projector Great restoration. Reminds me when I restored my wife's grandfather's Revere 16mm projector. It was a treat to play films she and her brother hadn't seen in over twenty years. __________________ Just playing with high voltage....

1st Oct 2008, 2:00 pm	#4
ppppenguin Retired Dormant Member Join Date: Dec 2003 Location: North London, UK. Posts: 6,168	Re: 1946 Ampro Premier 10 Projector Vinegar syndrome can definitely occur with safety film. It's not hard to imagine cellulose acetate being converted into acetic acid. http://www.brucecowellphotographer.c...%20Feature.htm AFAIK, all sub-standard film (ie below 35mm) used a safety base.

1st Oct 2008, 3:42 pm	#5
PJL Dekatron Join Date: Sep 2005 Location: Seaford, East Sussex, UK. Posts: 5,997	Re: 1946 Ampro Premier 10 Projector This is built and weighs like a tank so no rattling! The fan is the main noise contributer and the turret would make a good hair dryer. The amp is compact and it is interesting the switching prevents the lamp on without the fan but does allow the amp. After an initial panic I also read on wikepedia that 16mm films were all safety film. The disease appears to be confined to a set of copies of a play made in germany which are stored in cans. They have a distinct acetic acid smell and are shrivelled - I might try setting a match to a (very) small piece before I dispose of it. I am running a 120-125V lamp at 105-110V to preserve it but because it has a long throw lens the image across a normal room isn't that big and is more than bright enough. Without the films I really wouldn't have bothered with this restoration but I am now very pleased with the results. Although the films date from the late 40's to the early 50's many are copies of early pre-war films and as they would fail broadcasting standards I guess this is about the only way you are ever likely to see them.

1st Oct 2008, 5:53 pm	#6
chipp1968 Rest in Peace Join Date: Jul 2006 Location: Somerset, UK. Posts: 2,356	Re: 1946 Ampro Premier 10 Projector Very nice machine . I was given two prjectors without sound recently . same make. one from 59/60 other was 70s . the older machine is very attractive and well made .

1st Oct 2008, 9:07 pm	#7
PJL Dekatron Join Date: Sep 2005 Location: Seaford, East Sussex, UK. Posts: 5,997	Re: 1946 Ampro Premier 10 Projector Tried burning the vinegar film and it will not sustain a flame no matter how hard you try...so no fun there. Chipp1968 - did you get any films with yours? Last edited by PJL; 1st Oct 2008 at 9:12 pm.

1st Oct 2008, 9:10 pm	#8
ppppenguin Retired Dormant Member Join Date: Dec 2003 Location: North London, UK. Posts: 6,168	Re: 1946 Ampro Premier 10 Projector Just make sure you keep the vinegar film well away from any others. Apparently vinegar syndrome is contagious.

2nd Oct 2008, 1:45 pm	#11
ppppenguin Retired Dormant Member Join Date: Dec 2003 Location: North London, UK. Posts: 6,168	Re: 1946 Ampro Premier 10 Projector Acetate tape ought to be equally vulnerable to vinegar syndrome though I've not heard about it. Nitrate film doesn't produce acetic acid but can produce nitric acid. Still a nasty smell but rather different to vinegar. PJL: Congratulations on an excellent restoration.

2nd Oct 2008, 8:15 pm	#12
PJL Dekatron Join Date: Sep 2005 Location: Seaford, East Sussex, UK. Posts: 5,997	Re: 1946 Ampro Premier 10 Projector Audio quality is not exactly hi-fi at the moment but maybe it never was. I've fiddled around to refocus the audio optics and realigned the film and managed to get more HF but it remains quite distorted. Kalee20, it does have a mic input with seperate volume so I think I'll try a CD player next as it's possible the output valves are badly matched. The PM speaker is a bit of an antique too and at the mo its out of the cabinet as I'm still sorting out the grill. Think I best order a few spare lamps as I'm getting addicted...