Kneisley xenon conversion/Strong Trouper help

Gage

Member
I recently picked up a carbon arc trouper that had been converted to xenon at some point, mid-80s if I were to guess. Everything is functional and the whole setup is pretty interesting, but someone along the line made a few questionable choices, which I'm slowly working on rectifying (Example: someone wired the fan on a separate switch that allows it to be freely turned on and off with the spot still on). I'm mainly after documentation on the Kni-Tron rectifier side of things, anything more than an advertisement that would allow me to double-check the previous owner's work. Everything from a safety standpoint is already fixed, I just want to attempt to bring it back to a "by the book" conversion. I emailed the company (or at least what's left of it) and got no response, so this is my next option. It seems a similar, if not identical rectifier is still sold by Kneisley, for a specialty application. The specific model I have is no.M65RAX1C1, but I'm sure they have the same thing under several model numbers as well.
 

ship

Senior Team Emeritus
Premium Member
Try again at strong for a start at Ginger Dorn' <[email protected]> for a start for a contact. After that if she isn't helpful I can contact to the big boss. I manage the factory service for many Live Nation, and our spots from that brand and the Lycian brand for factory service of the fixtures in our area. We never have a problem with either company including up to search lights worked on once related to the strong company years ago de-linked.
Your fixtures are different than we normally do, but strong still has the knowledge base intact inspite of moving and changing owners over the years.. to provide advice better than anyone on the fixtures.
 

Gage

Member
Try again at strong for a start at Ginger Dorn' <ginger[email protected]> for a start for a contact. After that if she isn't helpful I can contact to the big boss. I manage the factory service for many Live Nation, and our spots from that brand and the Lycian brand for factory service of the fixtures in our area. We never have a problem with either company including up to search lights worked on once related to the strong company years ago de-linked.
Your fixtures are different than we normally do, but strong still has the knowledge base intact inspite of moving and changing owners over the years.. to provide advice better than anyone on the fixtures.
Sounds Great! I'll send out an email tomorrow and let you know how it goes from there. Thanks. (I had actually emailed Kneisley which I was referring to in my original post, hoping they had info on their own arc rectifiers, but they never answered me back)
 
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STEVETERRY

Well-Known Member
I recently picked up a carbon arc trouper that had been converted to xenon at some point, mid-80s if I were to guess. Everything is functional and the whole setup is pretty interesting, but someone along the line made a few questionable choices, which I'm slowly working on rectifying (Example: someone wired the fan on a separate switch that allows it to be freely turned on and off with the spot still on). I'm mainly after documentation on the Kni-Tron rectifier side of things, anything more than an advertisement that would allow me to double-check the previous owner's work. Everything from a safety standpoint is already fixed, I just want to attempt to bring it back to a "by the book" conversion. I emailed the company (or at least what's left of it) and got no response, so this is my next option. It seems a similar, if not identical rectifier is still sold by Kneisley, for a specialty application. The specific model I have is no.M65RAX1C1, but I'm sure they have the same thing under several model numbers as well.
IMHO, the big question is whether that conversion would still be considered safe in terms of the original Trouper housing being able to contain the results of an exploding Xenon lamp.

ST
 

Gage

Member
IMHO, the big question is whether that conversion would still be considered safe in terms of the original Trouper housing being able to contain the results of an exploding Xenon lamp.

ST
It does appear that a lamp has exploded in it before, with no major physical damage other than some slight internal scratching. I'm not worried about the thickness of the housing being an issue, its built well enough in that regard, and the red window for viewing the carbon arc already has some thick mesh over it to keep it from turning into shrapnel. The original hinged door on the lamp housing has no latch and is held closed by gravity, which concerns me slightly. I'm working on some sort of latch to keep it closed, but this is more of a "private collection" item and won't be used around others much if at all anyway.
 

derekleffew

Resident Curmudgeon
Senior Team
Premium Member
IMHO, the big question is whether that conversion would still be considered safe in terms of the original Trouper housing being able to contain the results of an exploding Xenon lamp.
If I remember from Strong class correctly, at room temperature a xenon lamp is pressurized to about 7 atmospheres; at operating temp, that climbs to about 14 atmospheres. Maybe @DELO72 can eluvidate.

I may be totally making this up, but ISTR conversion kits coming with a special screw to "lock" the carbon-rod access door(s). Even in the 1980s we knew that xenon lamps could explode violently. The term "devitrification" was on my lighting final. I think @SteveB has worked with conversions.

and the red window for viewing the carbon arc already has some thick mesh over it to keep it from turning into shrapnel.
I can't recall ever seeing a window that wasn't blue/Wood's Glass. Maybe it was replaced.

@Gage: two names for you, experts who used to be with Strong, one still may be. Jack Schmidt of Special Lighting Solutions. Paul Rabinovitz, president and one-time owner. Sorry I've lost contact info for both.
 

SteveB

Well-Known Member
Ah jeez Derek. I have to dig up long buried memories.

I never did conversions for the carbon arc Super Troopers I had at Brooklyn, we were fortunate to ditch them for 2 Lycian 1293 xenons. I have a very vague memory of using a Kneisley conversion when I was on a bus and truck, no idea where, it was 1979. As I was still a bit of a novice back then, I was unaware of the explosion issue with xenon, thus paid zero attention to the potential and whether or not the retrofitted spotlight was capable of containing the boom. I do not recall that Kneisley did anything special in the modification to upgrade a unit in the event the lamp went boom.

I will search CB to see if I posted a better memory of these units way back.
 

Gage

Member
Well, I went out and unearthed the spot to take a closer look at a few things. As @derekleffew mentioned, the sight glass on the lamphouse is actually blue, just my memory playing tricks on me. There are also two screw holes that were drilled and tapped to hold the door closed, both of which aren't being used (I'm definitely planning on throwing some screws in there as soon as possible). @SteveB, the housing appears to be completely unmodified from what it would have been in the carbon arc trouper, although everything that holds the lamp and reflector is aftermarket (see photo below). Please excuse the "messy" lamp house. It's the only thing I haven't touched yet as Id rather not have a lamp explode on me this early in the project. Overall build quality feels good enough not to have me worried about lamp explosions being an issue, that being said, I haven't been next to a xenon lamp this big when it's in explosion mode. Haven't heard back from Strong yet either, going to give it another day or two though.
IMG_20220512_164630__01.jpg
 

ship

Senior Team Emeritus
Premium Member
Where are you would be a start in authorized tech people to see what you have. I personally have not worked on a fixture like it, but could advise if local. PM me if further from Strong is not helping. They are normally great for help, I in PM ask can forward your problem.
Not something I have worked on before, but could figure out if the local service center.
 

Gage

Member
Where are you would be a start in authorized tech people to see what you have. I personally have not worked on a fixture like it, but could advise if local. PM me if further from Strong is not helping. They are normally great for help, I in PM ask can forward your problem.
Not something I have worked on before, but could figure out if the local service center.
Sounds good. I'll give it a few more days and if I don't hear back ill go ahead and PM you. Thanks.
 

Gage

Member
Thought I would post a small update. I ended up getting an email from strong, Paul Rabinovitz specifically. Unfortunately, he said everything they have on the trouper is already online, and that strong doesn't have any info on the Kneisley conversion. Good news though, I have checked everything over and fixed anything electrically questionable. The lamp strikes and everything runs as expected, I'm just not looking forward to swallowing the price of a new lamp when the time arises, it will cost more than the whole spot is worth for sure. If anyone knows a tech in the Orange County California area that would be willing to give the thing a quick look over and tell me if the lamp house is remotely safe, please send their info my way.
 

derekleffew

Resident Curmudgeon
Senior Team
Premium Member
I'm pretty sure Sun Valley CA is not near Orange County, but I'd venture to say no one on the west coast knows more about xenon lamps than the folks at semi-defunct http://www.arclightefx.com/ . Someone may take a purely historical interest in your project.
 

Gage

Member
I'm pretty sure Sun Valley CA is not near Orange County, but I'd venture to say no one on the west coast knows more about xenon lamps than the folks at semi-defunct http://www.arclightefx.com/ . Someone may take a purely historical interest in your project.
Sun valley is quite a ways away, especially when you have to haul a few hundred lbs of followspot. I'll shoot them an email via one of the addresses listed on their site though, if nothing else they might get a bit of a kick out of it.
 

Mac Hosehead

Well-Known Member
I used to service Stromg Carbon Arc spots and then Strong Xenon spots when they came out. I don't remember exploding lamps being much of an issue with them. The Strong Xenon spots had an air pressure switch in the lamphouse that would extinguish the lamp if air flow was compromised. I don't know if the arc conversions have anything similar to it. They also had switches mounted to sense any panel that could be removed while operating.
 
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Gage

Member
I used to service Stromg Carbon Arc spots and then Strong Xenon spots when they came out. I don't remember exploding lamps being much of an issue with them. The Strong Xenon spots had an air pressure switch in the lamphouse that would extinguish the lamp if air flow was compromised. I don't know if the arc conversions have anything similar to it. They also had switches mounted to sense any panel that could be removed while operating.
This conversion does have a safety switch on the door, however, no airflow switch was ever provided to my knowledge. In fact, on mine, there is (well "was" until I got finished with it) a toggle switch in place that allows you to turn the fan off... with the lamp struck.
 

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