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Other Vintage Household Electrical or Electromechanical Items For discussions about other vintage (over 25 years old) electrical and electromechanical household items. See the sticky thread for details. |
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14th Nov 2013, 9:41 pm | #1 |
Dekatron
Join Date: Apr 2005
Location: Bewdley, Worcestershire, UK.
Posts: 4,748
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16mm Projector Repair
The museum where I work as a volunteer needs a 16mm Bell & Howell cine projector repaired. The problem is in the lamp housing, and the lamp contacts have been overheating and burning out. This is a bit outside my own areas of expertise, and they have been trying to find a local repairer, without success.
Would any member in the Dudley or West Midlands area be able to offer such a commercial repair service, or provide me with some detailed advice or service data? Many thanks,
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Phil Optimist [n]: One who is not in possession of the full facts |
15th Nov 2013, 9:24 am | #2 |
Hexode
Join Date: Oct 2011
Location: Portsmouth, Hampshire, UK.
Posts: 354
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Re: 16mm Projector Repair
We used to have the same problem on Blakell loading machines' top lights. A photo of the contacts might be helpful.
Regards, Robin. |
17th Nov 2013, 11:41 am | #3 |
Dekatron
Join Date: Jun 2013
Location: East Sussex, UK.
Posts: 3,326
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Re: 16mm Projector Repair
Have you found someone? I'm a bit too far away to help.
If not, what is the lamp type. Many used lamps similar to halogen downlighters and are 2 pin sockets on wires with the lamp fixed to the projector. Check the wattage/voltage, I think many were 24 volt @ 250 watts, about 10 amps. That is above the normal downlighter ratings of 12 volts @ 50 watts about 4 amps, but a heavy duty version might work. Original types are available, I've seen them if you do a search. They are not difficult to replace - just follow the original wires. Remember that you can't solder directly to the base, there must be welded or crimped wire to allow for heat from the lamp. |
17th Nov 2013, 1:47 pm | #4 |
Octode
Join Date: Jan 2013
Location: Barnsley, South Yorkshire, UK.
Posts: 1,517
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Re: 16mm Projector Repair
Phil, in my experience it is usually contact resistance in the lampholder which causes the trouble; with these high current high temperature lamps the contact burning can not only further damage the holder but shorten the lamp life. I have to say that once an holder has been badly overheated it is very difficult to burnish up the contacts sufficiently to cure the problem, metal gets oxidised too deep down and the contact resistance can't be lowered far enough. You could give it a try though - very fine 'wet & dry' and keep going until you get to very shiny metal - polish up with cotton bud soaked in 'brasso' - then clean up all debris with a cloth moistened in 'meths' let it dry off and see how you go. I have to say though that a new lampholder may be the only permanent solution.
By the way check the airflow over the lamp if it has a fan is it running and are the grilles dusted up. And finally, because this sometimes happens, has it got the correctly rated lamp in place?, it's not unknown for someone of little knowledge to think they can get a brighter picture by 'upping' the wattage then, years later, someone else replaces the lamp unknowingley with one that's the same - perpetuating the problem. |
22nd Nov 2013, 9:52 pm | #5 |
Dekatron
Join Date: Apr 2005
Location: Bewdley, Worcestershire, UK.
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Re: 16mm Projector Repair
Thanks for all the advice, chaps. No, I've not found a local repairer yet, so I'll probably have a look at it myself next visit. I've been told that a previous repairer replaced the original lamp connector, possibly with inadequately-rated components. We will see!
As a related question, are there any recommended suppliers of Bell & Howell spare parts in the UK? There must be thousands of vintage projectors in existence.
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Phil Optimist [n]: One who is not in possession of the full facts |
23rd Nov 2013, 12:12 am | #6 |
Hexode
Join Date: Nov 2006
Location: Near Lincoln, UK.
Posts: 483
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Re: 16mm Projector Repair
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23rd Nov 2013, 10:38 am | #7 |
Dekatron
Join Date: Apr 2005
Location: Bewdley, Worcestershire, UK.
Posts: 4,748
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Re: 16mm Projector Repair
Thanks Paul, I've e-mailed them.
Cheers!
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Phil Optimist [n]: One who is not in possession of the full facts |
23rd Nov 2013, 12:38 pm | #8 |
Octode
Join Date: Jan 2013
Location: Barnsley, South Yorkshire, UK.
Posts: 1,517
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Re: 16mm Projector Repair
Another 'port of call' may be the Projected Picture Trust www.ppttrust.org
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27th Nov 2013, 10:35 pm | #9 |
Dekatron
Join Date: Apr 2005
Location: Bewdley, Worcestershire, UK.
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Re: 16mm Projector Repair
Thanks for the suggestions, chaps. I'm going to have a close look at the machine in question tomorrow. Once I know the model number, and with a bit of luck found the handbook or service manual, things may become clearer.
I have actually visited the Projected Picture Trust at Bletchley Park (many years ago) but from their website it appears that they only restore their own equipment, and are mainly concerned with 35mm projectors. Classic Home Cinema don't do repairs either, but they tell me they may be able to supply spare parts, so I'm going to follow that route. I have also found a good source of information at Paul Ivester's American website.
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Phil Optimist [n]: One who is not in possession of the full facts |
28th Nov 2013, 9:54 pm | #10 |
Dekatron
Join Date: Apr 2005
Location: Bewdley, Worcestershire, UK.
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Re: 16mm Projector Repair
Hi again,
After a close inspection today, it's patently obvious what has happened to this projector, a 16mm Bell & Howell TQ1 'Filmosound 652'. The metal parts inside the lamp connector have burnt away internally, and no longer make contact with the pins on the halogen bulb. I did confirm that 24 volts AC is present on the ends of the wires. I am not convinced that the fitted lamp connector is the original type, and to me it just doesn't look man enough for the job of reliably carrying 10 amps in close proximity to a 250 watt lamp. The connector has a ceramic body and mica front, and has indeed been replaced by a previous repairer. If anyone can confirm what the correct lamp connector should look like, it would be much appreciated! Many thanks, Phil
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Phil Optimist [n]: One who is not in possession of the full facts |
28th Nov 2013, 11:27 pm | #11 |
Dekatron
Join Date: Jun 2013
Location: East Sussex, UK.
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Re: 16mm Projector Repair
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28th Nov 2013, 11:45 pm | #12 |
Dekatron
Join Date: Apr 2005
Location: Bewdley, Worcestershire, UK.
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Re: 16mm Projector Repair
Aha! The lamp connector in your photo is much more substantial than the one in mine.
Thanks for the lamp info too.
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Phil Optimist [n]: One who is not in possession of the full facts |
29th Nov 2013, 10:29 am | #13 |
Dekatron
Join Date: Jun 2013
Location: East Sussex, UK.
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Re: 16mm Projector Repair
Looking at a picture of the lamp (via go oggle)- it appears to have 2 same sized pins. The holder in your picture shows 2 different sized holes in the mica cover. Perhaps that is the problem, with the larger hole having a larger contact and not connecting properly with the pin. Especially as it's carrying about 10 amps.
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29th Nov 2013, 11:17 am | #14 |
Dekatron
Join Date: Jan 2012
Location: Brentwood, Essex, UK.
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Re: 16mm Projector Repair
I had a similar problem with a Eumig 8mm projector, which uses a 12v 100w lamp with a G6.3 2 pin base. I got a G6.3 ceramic lampholder from Maplin. It was slightly too big, and I had to cut away a non-critical part of an internal wall of the lamp housing to fit it in.
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29th Nov 2013, 10:31 pm | #15 | |
Dekatron
Join Date: Apr 2005
Location: Bewdley, Worcestershire, UK.
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Re: 16mm Projector Repair
Quote:
There is no doubt that your lamp connector is a much more substantial affair than the one fitted to our projector. The good news is that Classic Home Cinema are able to supply the correct connectors and bulbs at a reasonable cost. I'm pleased to report that my problem is now resolved, thanks to the Forum (yet again!) and this thread can now be closed. Many thanks to all contributors, I'm very grateful.
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Phil Optimist [n]: One who is not in possession of the full facts |
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30th Nov 2013, 1:18 am | #16 |
Dekatron
Join Date: Nov 2003
Location: Heckmondwike, West Yorkshire, UK.
Posts: 9,642
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Re: 16mm Projector Repair
We don't normally close threads, except parts offered or wanted. However as this is not one of our core subjects, and is satisfied, I will. It can be re-opened if requested.
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