Corroding S4 bases

Hey everyone, just curious if anyone has any solutions to this problem that has seemed to plague my theatre. Our Source Four ellipsoidal bases are constantly corroding/oxidizing and we've tried a thousand and a half ways to fix them. The only solution we've found that works is replacing the contacts, but unfortunately, this gets expensive fast. We've also just brushed out the contacts with wire brushes, but they only work briefly before going back to the original problem. We aren't sure why they keep dying, but it's killing our inventory.

Anyone else had this problem? Or a solution?
 
You can use a dremel on the bases to clean the contacts. They will still eventually wear out, but it's a quick, easy way to clean them.
 
Do you keep buying the same brand of lamps over and over? Have you contacted ETC about the problem? It just so happens we have a lamp expert here on CB, and he'll be along shortly, so I'll defer to him.
 
Here is another question, do you change the lamp base and then put the same lamp back in? Once the pins on a lamp start to oxidize they will continue to even in a new lamp base. Why? Because the oxidation and carbon deposits and any other gak that gets in there resists the flow of electricity. More resistance begets more heat, and more heat begets more destruction of the lamp base and pins.

So, even if the lamp is good it will still cause bad things to happen if you continue to use it. You can clean the contacts, but you have to be carful because if you scrape or grind and you change the shape of the contact you can cause arching when it doesn't seat properly in the lamp base. Also the oxidation/corrosion can cause the shape of the pins to change thus causing more arcing. Yet one more reason to to keep using the old lamp even if you clean it.
 
I should have remembered that, Alex. In the 80s I had a Strand-Century dealer tell me, "it's like VD: lamp causes bad socket, then bad socket causes different bad lamp, then lamp causes different bad socket....the gift that keeps on giving, and before you know it, your entire inventory is 'infected.' "
This was about TP-22s and FELs, but the same applies. S/C replaced about 30 of my sockets for free (some which had come out of Kliegl fixtures...shhh!) They suggested NOT to use emery cloth or Dremel tool on the lamp pins, as that would make them smaller and thus cause more arc-ing.

I'm pretty sure ship has addressed this issue before, I just can't find it.
 
Here is another question, do you change the lamp base and then put the same lamp back in? Once the pins on a lamp start to oxidize they will continue to even in a new lamp base. Why? Because the oxidation and carbon deposits and any other gak that gets in there resists the flow of electricity. More resistance begets more heat, and more heat begets more destruction of the lamp base and pins.
So, even if the lamp is good it will still cause bad things to happen if you continue to use it. You can clean the contacts, but you have to be carful because if you scrape or grind and you change the shape of the contact you can cause arching when it doesn't seat properly in the lamp base. Also the oxidation/corrosion can cause the shape of the pins to change thus causing more arcing. Yet one more reason to to keep using the old lamp even if you clean it.

Especially in older fixtures, I find that most physical notes tend to lend themselves to a bad base more often then a bad lamp.

Remember, these things have to pass 5-7 amps through them in extremly high heat situations. S4's don't have the best designed base cap, but at least swapping out the leads is quick to do and relativly cheap. I always find it interesting when people will spend 15 bux on a new lamp every time the base fries the contacts, but go nutz when people will run 6 lamps through without replacing the base.
 
Especially in older fixtures, I find that most physical notes tend to lend themselves to a bad base more often then a bad lamp.
Remember, these things have to pass 5-7 amps through them in extremly high heat situations. S4's don't have the best designed base cap, but at least swapping out the leads is quick to do and relativly cheap. I always find it interesting when people will spend 15 bux on a new lamp every time the base fries the contacts, but go nutz when people will run 6 lamps through without replacing the base.

Older caps or newer caps?
 
"it's like VD: lamp causes bad socket, then bad socket causes different bad lamp, then lamp causes different bad socket....the gift that keeps on giving, and before you know it, your entire inventory is 'infected.' "

I love it and gonna steal it. For the most part, I have nothing to add to the above wealth of comments. Also a good point about people complaining about the price of replacing the lamp socket yet they don't mind going thru lamps left and right - or don't bother inspecting the used ones for this condition so as to prevent a problem.

Small sockets under and possibly including G-12 in size don't take to cleaning very well or Dremmeling. - Add to this the thinness of the contacts once if even possible to properly clean them and you get around 6.x amps running thru a very small thickness of no longer even gold coated metal making up the lamp base with very high heat in the area.

Contact cleaner also won't work as with deoxident in not working, not rated for the temperature and first you would have to remove what is wrong before you can coat the surface and or clean out any residue left. These things are not rust/oxidation reformers, and even if they were what the oxidation / welding / melting / corrosion has been reformed to does not conduct very well. Other types of deoxident such as copper imbeded also would not work in such a small area given you have to first clean the contacts, and the chance of applying too much and shorting to the frame or other contact.

There is reports of copper filled deoxident working well (not tried by me) in the case of larger lamp sockets that have been properly resurfaced but have some pitting so as to fill in the holes as it were but not where the socket has not been already resurfaced.

Consider surface contact when looking at bad lamps/sockets. Current does not travel thru carbon buildup / burned and melted areas easily or thru areas that lack physically touching the lamp base with a good connection such as in the case of pitting or a loose fitting lamp socket. The wattage of the lamp has not changed and that means the amperage is traveling thru what little area is in contact with the lamp. This amperage due to resistances in the metal and heat given off by the lamp than gets really hot and both expands the bad area if not welds lamp base to the lamp, and creates new areas of heat. This in addition to given high resistance of the lamp base while current if flowing a lot of heat is given off in exchange - hot enough to weld metal such as the lamp base contact to the pins of the lamp in some cases. (This granted the amperage of a HPL lamp is not all that high and the gold contacts don't weld well to the nickel plating of the HPL lamp as easily as with other lamp / socket types.) Gold' has a fairly low melting temperature also - don't believe ETC switched materials for this but it is probably very low amount of gold in the socket contact. (Forget if it was fully gold contacts or just coated gold contacts.)

ETC recently upgraded their lamp base sockets recently as I remember also so it might be better now. Believe it's an Osram socket that I could verify the material making up the contact given some time and if it's of interest. The upgraded lamp bases that are now an all in one part with porcelain and mica insulator is a good thing. Once had a tech person replace a bunch of lamp bases on some fixtures but she forgot to install the mica inculator behind the contacts. There was a bug hunt in finding the fixtures now shorting to the frame of the fixture and there was a lot of fixtures she changed the lamp bases on.

While the upgraded lamp base is probably superior in being longer lasting than the older version (don't know, don't run that department) and the all in one lamp bases now are safer given a potential safety hazzard if someone forgets the mica behind the contacts, I'm kind of dissappointed ETC did not just offer the sockets all by themselves without wiring attached. This at least for the old style part was just a crimp terminal where it attaches to the wire with a lamp base socket on the end of it. Will have been not more than like a buck or two per crimp as opposed to like twenty dollars for the wire/crimp assembly. This granted it necessitates the end user able to properly crimp the wire to the crimp terminal part of the socket, but for high end users such as myself that has that ability it should have been an option. This will have saved hundreds of dollars if not more over the years were we just able to do or own crimping. This much less often the heat wire feeding the lamp socket contacts was in perfectly fine shape and did not need replacement.

Still the S-4 light fixture is what it is now - what fifteen years old now. I hear thru the grape vine that new lamps for them are under way and perhaps new sockets will also be TBA. In the mean time, Osram does make the ETC lamp base assembly, any theater or lamp supplier that can get an Osram lamp might be able to get it cheaper direct than thru the ETC route.
 
I don't physically deal much with HPL lamps in their demise other than collecting them up for a study at the moment (those that know who I am off line, send me your spent HPL lamps for the next month or three to help with this study - it could be really useful in advancing the lamp science and I might be able to swing some exchange). I do buy the lamp base replacement parts and save a good amount of money in getting them for a multitude of lamps thru my lamp distributer as opposed to direct from the fixture manufacturer. This is the case of the HPL and even Mac 2K lamp bases, but I buy such parts in bulk as a minder here in what saves me money does not at all times mean it will be cheaper on the onezees or even twentyzees amounts.

The following photos show examples however of some Mac 2K or Mac 700 lamps which also had bad lamp bases which caused lamp failure. Often those changing the lamps won't note the lamp socket or even condition of the lamp base on the lamp and they will just return the lamp as bad or "exploded" but won't consider on these $100.00 plus lamps each what caused that failure. AT times before I even get to inspecting and tracking the lamps on the computer, they will have already have had two or three lamp failures in the same lighting fixture due to a bad fixture lamp socket and still not have changed it. That means the price of lamps, plus man-hours at times in premium IA labor for the time to change the lamps each time all caused by a bad fixture lamp socket that is killing off lamps left and right. Do my best of course to warn the crew chiefs of the tours... pull VL3K SP 126 from service ASAP, it's on it's third lamp in six months now caused by the same bad lamp base, but often that is really hard to do in figuring out or remembering what fixture that was amongst a few hundred lights and won't be found until the next lamp fails thus costing upwards of well over $400+ per time it happens on each fixture before it has a hope of a problem solved. This given a lack of inspecting the lamp and understanding what caused the failure.

The following is some photos of bad lamp bases caused by bad fixture lamp bases. 034, note the lower one with it's darker color of lamp base and bent screw thread. 009 while not such a great photo shows a monofoil that escaped thru a pinch crack on the lamp. Question is what caused this failure, the bad fixture lamp base overheating the lamp or a fault in the lamp? Overheating of the fixture socket in this case caused overheating of the lamp and it's failure -another stage hand's day rate in one bad lamp means one less day someone is employeed - at least how I consider such things. Of the three lamps in photo 001, none show signs of overheating and all were lamp based failures.
 

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Hey, I may have touched those very lamps! Seriously, I don't mean to hi-jack, but the above post may help to illustrate some of the "hidden" costs of owning Moving Lights. A MAC2000 Profile retails at around $10,000. The lamps cost around $125. Why purchase when you can rent one for $150-250 per week? Then maintenance becomes ship's problem. I seriously cannot figure out the economics of anyone owning moving lights, other than the cheap disco types (you KNOW who you are, and that's fine).

How about those EHD/EHG/FEL lamps whose metal base was filled with sand and when the pinch seal epoxy broke you'd spill sand all over the stage. Might have been Westinghouse? brand. Then USHIO, an unknown Asian manufacturer came out with a truly superior product, a g9.5 with an all ceramic base. But Wiko? lamps were absolutely horrid. Vendors used to charge one price for Foreign: including Thorn (so-so, their FEL wouldn't fit thru holes in some reflectors), and a higher price for Domestic: GE or Sylvania. Yes, at one time I was almost as knowledgeable as ship about which brands of FELs I liked and didn't. And "pregnant" 750T12/9's! Downright obscene sometimes!

One more aside and then I'll return you to your program. I remember my boss at the lighting rental shop spending all week trying to source ceramic wire nuts so we could use TP-22 sockets with 6" tails inside 360Q lamp caps. For some reason, they had gotten a great deal on these sockets, but the time and effort we spent using them instead of more correct ones with 36" tails taught me a valuable lesson.

Back to topic: I suggest purchasing some extra lamp caps to have available to swap out at the first sign of corrosion/arc-ing. Then replace sockets at your leisure so always have some ready to go. As others have said, saving a $20 bad socket that ruins multiple $20 lamps is poor economics. The other important take-away is to inspect your failed lamps when replacing them. Check the pins and sockets also.

Happy Lamping.
 
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extra lamp caps no matter the fixture is always a good idea. Got a few lamp caps sitting in the garage for fixtures I don't even own any longer. But this is a really good idea - find a problem in changing a lamp, call for the new cap if not just swap out both lamp can cap automatically and inspect on the ground. At very least one extra lamp cap on hand means the difference between a working fixture and one that no longer works.

Economics... yep, it does kill me at times to see some stuff or even have to trash a perfectly good example of lamp that should be warranty and return simply because someone screwed up the lamp history or didn't take a minute to fill in the tag on the box denoting who what why. This much less in being the lamp buyer, and knowing the day rate of an average tech person doing the math - really kills me the cost of lamps over labor. Just had a rental lamp come back from a ISU rental specifically to the point of renting instead of owning. They didn't bother to fill in the tag and thus another, urr as he says in lamp cost down the hole the owner of the lamp/fixture eats. One can be sure however that TD at my alm. will get an E-Mail and the person that rented the gear to them will be CC'd that either they fill out the lamp tags on lamps they change or it should be required that one of our people is hired to operate the gear rented as part of the cost if they wish to rent from us. Just lost money on the rental not due to a bad lamp - such things happen, due to them not filling out an easily seen lamp tag with a few lines of info about the change to fill in. Short of this on a lamp that could have been sent back, this rental just lost money. At very least, their next fixture rental should be expected to be a bit more steep in price thus at times how much renting such fixtures cost if not such fixtures requiring shop staff to babysit the gear added to the cost. Those that don't at times also don't care for their gear and it possibly won't work for the production.

Just talking tonight with a designer that's been around the block a few years. He mentioned how another company does their lamps, they have a bucket of new / good lamps, and a bucket of brown ones. For good stuff they install the good lamps, for other stuff such as rentals especially, its' the brown ones. Might explain why when we rent gear from other places we tend to get brown lamps if not fixtures in need of service - given I'm told fixtures get turned on inside the road case .. yep it works but not as we do for all productions ours or a rental bench focused against the other fixtures on the show and color matched. Bucket of blue and a bucket of brown, kills me no lamp tracking done one lamp as good as another.... might explain why many lamp companies don't do individual serial numbers on their lamps any longer. As if the day rate of skilled labor for one lamp were a dime a dozen in lamp cost. Really kind of an insult beyond the "hand made" aspect of the lamps - on axis lamp twists to them and all, no serial number means disposable like the labor using them.

On the other hand, I did get a lamp changed by "Local #2" tonight. Thoroughly impressed me, they must be holding classes in reading and writing because while written in Sharpee that bled all over the label in making it hard to read, they did fill out all lines of the tag. Boy, that Local 2 person (who names their kid Local 2 anyway, as written on the "changed by" line?) for the first time ever that I can remember took the time to do such a thing and helped fill out a different lamp tag for a lamp which will be returned and that lamp's cost will be refunded in having a manufacturing problem before 2/3 of it's expexted lamp life was achieved.

These two lamps returned, or one of them returned, one in the trash. I normally average 10% return, 10% try again in a different fixture and 80% recycle and it's all very much about the lamp history and an average of five minutes time on each lamp in noting its problems, history and cause of failure on the computer that currently has about 14,000 individual lamps in its tracking. I'll worry about the micro cracks and pinch bleeds, you fill out the tag and describe why this fixture became suspect. Takes an average of five minutes per lamp in tracking and inspecting it on the computer than installing its replacement also into the computer now assigned to the lighting fixture. This as opposed to a minute or so to do the date, who, reason, lamp hours, fixture serial number and lamp serial number. From that info and what I can figure out in examining the lamp I can do a valid claim for return of the lamp if it qualifies or be able to track lamp type/brand problems in switching to other brands following a trend of problems with a brand.

This is a 55gal. drum and this is one years worth of bad moving light and other arc source lamps with another drum on the way and around 1,000 more from last year to inspect. A few xenon follow spot, strobe and Big Light lamps, a few Sportslighter lamps, a few shop lamps but mostly around 1,000 Mac 2K lamps, 500 or so Mac 700 lamps and lots of other lamps including the new to the market "Fast Fit" lamp types. This is really expensive to recycle also - about as much as a new mid-range moving light. I expect say 10% or much more of these lamps could have been sent back to the manufacturer for evaluation and possible refund due to lamp flaw if only the lamp history were sufficient and not in question such as said to be installed in one fixture, yet removed from another fixture. Another 5 to 10% of them probably came out of fixtures with bad lamp sockets thus destroying the lamp before the expected lamp life or even as above with the warranty lamps, at least 2/3 of that.

Back to the point is that 5 to10% of lamps or so above and in this drum that came from fixtures with bad lamp sockets. AT very least for half or more of these 10% lamps there is no excuse for given at times in tracking the lamp serial number to fixture assignments thus lamp history, I can tell how many lamps are installed in any fixture and even beyond lamp inspection of a overheated lamp base, how many times for any fixture this next perfectly good lamp into a bad socket has happened in a row. Each of these lamps have a serial number or I write if not even engrave one into the lamp in making it individual. That's for moving light lamps, go another drum for fluorescent lamps and a third for halogen/incandescent lamps. This given most halogen lamps are both less commonly used on shows and when they go bad they are thrown out. Still the halogen lamp drum is about 3/4's full - granted quite a few PAR 64 and other PAR lamps in it. Moving light lamps I can track and track down the fixtures with bad lamp bases, on halogen / conventional type fixtures it's all about the inspection and hopefully about the shop prep of them.
 

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...simply because someone screwed up the lamp history or didn't take a minute to fill in the tag on the box denoting who what why. Just had a rental lamp come back from a ISU rental. They didn't bother to fill in the tag and thus another, urr as he says in lamp cost down the hole the owner of the lamp/fixture eats. One can be sure however that TD at my alm. will get an E-Mail and the person that rented the gear to them will be CC'd that either they fill out the lamp tags on lamps they change or it should be required that one of our people is hired to operate the gear rented as part of the cost if they wish to rent from us....
Well ship, I'm hurting my little brain, but I believe yours is the only company that even HAS "lamp tags" and/or tracks lamps. I know the Borg doesn't, but if anyone should it would be them. I'm gonna try to change one of your lamps, whether it needs it or not, just to fill out the tag (maybe in Keno crayon) for you. How much does a 1.2Kw globe for a Lycian M2 cost?
 
There are a few companies following our lead and the lamp manufacturers do recognize this tag and the tracking sheet that goes with each lamp. Often it spells the difference between a lamp that needs to be inspected for possible refund and a lamp that given I have already inspected it and tossed out the not valid claims, just gets its refund with a quick turn around. I'm serious about this also, you want a warranty claim for a moving light lamp, best be able to show a valid reason for it's return. In some cases I will even have a lamp I know is bad but looks good that I will send out to try again one if not two more times after the first rejection. This just to verify that it is the lamp and will be a valid bad lamp claim. Five minutes per lamp however and you gotta know what you are looking for on them. One little pinch crack that gets a bit too deep means the difference between a lamp that goes back verses a lamp that just took out a fixture reflector, and fixture reflector warranty claims are much more difficult to show was a lamp problem. On the other hand, the reflector is often much more expensive in parts and labor than the lamp. Pinch crack forming, deep pinch crack forming, long pinch crack, pinch bubbles at the electrode, pinch crusties, inner globe pinch inlets, pinch crack due to lamp removal, pinch crack with lead in wire weld bleed, verses pinch failure are all amongst other lamp descriptions and things to watch for very much different things. Some spell the end to the lamp, others can be fine for hundreds if not thousands of hours but need to be watched. Each lamp has its own set of things to look for and things in common well beond the concept of simple snowball.

Not funny. My cost on the HMI 2500w/S lamp is discounted dealer and not public. Still not cheap. Though on follow spot lamps such as this I am not tracking them on the computer at this point. Near doing so but not quite yet as far as lamp/serial number/fixture assignments. Get a Gladiator IV and that lamp is tracked. On the other hand, filling out the tag on the box even for that lamp is very helpful - this granted lamp hour tracking is archane for them. As much info as possible and it means a possible return if appropriate though doubtful if I buy more than two dozen of this lamp type per year thus under my notice as far as tracking goes at this point.
 
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sorry about hijacking the thread a point is there somewhere as with the next PS thought.

Beyond lamp tracking I also got really tired of seeing Mac 700 lamps installed into Mac 2K fixtures. Yep it works and the lamp will last about 300+ hours. Even a Mac 550 lamp in theory will work for a wile - in theory at least. Recently I noted a Mac 2K lamp installed into a Mac 700 fixture and was astounded that it took a few hundred hours also in working to detect a difference sufficient to pull the fixture. Checked the lamp history and as near as I can tell this is fact that the 1.2Kw lamp struck an arc in a 700w fixture.

Screamed up a storm with Osram about them using the exact same lamp boxes for the two types of lamp without any progress in them even changing the font size of the lamp type writing. So I paid a local printing shop to print me up 1,000 each 1,200w and 700w labels in 1" x 3" size. Each lamp now gets a sticker and I'm yet to see problem repeated.

Following this and given Phillips with their crappy boxing and overly huge boxes often also uses the same boxes for different lamps and a smaller font than they used to, I am now printing up lamp type labels for those lamps also and sticking them on the box on one if not two sides. Hopefully problem solved though I would give credit to the person that can put a 1.2Kw fast fit lamp into a fixture using a MSR 575HR lamp type at least.

As a general theory, in preventing the HPL lamps of different wattages, if not preventing the long life and 120v lamps from getting stuck into the system - as does happen also, one can sticker the boxes so as to make it easier to read. This also saves money on lamps.
 
...Beyond lamp tracking I also got really tired of seeing Mac 700 lamps installed into Mac 2K fixtures. Yep it works and the lamp will last about 300+ hours. Even a Mac 550 lamp in theory will work for a wile - in theory at least. Recently I noted a Mac 2K lamp installed into a Mac 700 fixture and was astounded that it took a few hundred hours also in working to detect a difference sufficient to pull the fixture. Checked the lamp history and as near as I can tell this is fact that the 1.2Kw lamp struck an arc in a 700w fixture...
How can the Programmers/LDs/Techs NOT NOTICE this? "Hey that lamp is twice/half as bright as it's brother, what going on?" Sort of like I've had programmers tell me VL3000 lamps hold their color as they age better than the MAC2000 lamps, little do they know it's the exact same lamp!
 
The lamps in the mac 550 and 700's have different bases. I dont know about the lamp in a 2K, i figured it would be a different base also. I dont know why they would make the all the same base. I figured a mac 2k would take a regular MSR1200 or a MSR1200sa.
 
Man a lot of those lamps still look good. We usually run the 1200's till they explode or are to dim to do anything with, which ever happens first. (we only allow lamps to blow up in instruments that have metal reflectors, NOT GLASS) I know the msr700sa's will run till they get really big and turn green and keep on running... :D
 
....but the above post may help to illustrate some of the "hidden" costs of owning Moving Lights. A MAC2000 Profile retails at around $10,000. The lamps cost around $125. Why purchase when you can rent one for $150-250 per week? Then maintenance becomes ship's problem. I seriously cannot figure out the economics of anyone owning moving lights, other the the cheap disco types.

Do the math. If you're a producing theatre, then just having to pay trucking for said rentals would very quickly make those rental prices less attractive. Also, for non-profit organizations, it's often easier to BUY equipment than to rent it. Making "capital improvements" to the organization isn't accounted the same way as say buying gaff tape and gel.

If I use that one MAC2k for a year, based on your pricing above it would cost $7800-13000 in rental costs. Now I know it would be a bit less for a long rental, but that still isn't cost-effective for me, especially if it's a small number of units. Now, if we sent that unit back to the shop each time a show closed, then got another unit for the next production (for me that would be a 1-4 week window, depending on which of my venues and the time of year). Each trip to the shop costs me $300-600 EACH WAY (PRG/4Wall recent delivery quotes).

Also, by spending that money up front, then you always have that gear available.

Your mileage may vary.... ;)

--Sean
 

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