It’s called finger
[email protected]&ing. Where the oil from one’s skin touches the lamp and it caused the
halogen effect to improperly cool by way of heat reflected off the oil coated surface. Bad thing to see, once did in an entire theater’s inventory this way myself early on no doubt in a similar era of understanding what the heck I was doing beyond functioning. Still have some of them bubbled lamps, at times the
filament would stretch as if blown towards the
bubble to the
point that the
filament itself would encase itself within the glass. It would still work even if surrounded by the glass outer
bulb. This until at least it finally had a blow out.
This all as opposed to real blow outs where the
filament possibly due to a
voltage spike while already operating at times will shoot
thru the outside wall of the glass in the glass having like a bullet
effect worth of hole frozen in it, and the opposing side of the lamp having a puckered like appearance due to the gasses sucked out of the lamp.
This also as opposed to the bloated lamp where someone did a really good job of touching the lamp and there is a huge
bubble blown up all over the
globe as if balloon. Such lamps often have a silver coloring to them due to the deposits from the
filament finding the outer
globe of the lamp hotter than the
filament at some
point before it also fails.
Love lamp failure science, at times at work, it’s as if I am the CSI of lamps - who did what. This especially for metal hallide type lamps. This past weekend I had a HSR 575/72 lamp that had something like 4,950 hours on a lamp rated for 750. Sent the “looks brown” lamp back for another
play test, why stop now, let’s at least take it up to 5,000 hours before replacing it. Next lamp by chance had over 9,500 hours on it... Took a look at the amount of bubbling and wear to the electrodes, yep, this lamp has been in service for about 40 hours in reality, but we have a new world’s record in a lamp I now have no chance of returning to the manufacturer due to also being “brown” in look to it but our not re-setting the lamp life counter on lamps changed in this
fixture. Hmm, over 9,000 hours... that means at least the last 12 lamps installed in this
fixture have not had the lamp counter on the moving light reset. I tack the
fixture serial number and know who the idiots “professional lighting technicians” are that don’t know how to re-set a lamp counter...
Anyway, lamps doing odd looking things like getting bubbles are often from people touching the lamp. Sections of the
filament that fall off a hanger or in having a broken hanger kind of fall off and go off free hanging or at an angle in also at times touching the
globe often comes from rough handling of the
fixture.
Be sure and examine the lamps and
fixture sockets each time a lamp is changed - look for arching and corrosion as a tell tale sign of something that needs either re-surfacing - an advanced technique or replacement. Short of having a look at what went bad, you will burn
thru what’s good in making it arch it’s way into being bad.
Get the gear including and especially beyond the lights also in need, specifically the dimmers and board in for a yearly service
call like yesterday if you want to depend upon such things working tomorrow. Budget for doing this professionally yearly or you need to start budgeting for new equipment instead at a higher cost immediately.
Start studying for your new trade. Lots of good books out there and good past posts here and say on Stagecraft to read. You are responsible now for the gear it would seem, time for you to be responsible for it and not rely on anyone other than
leg work for assisting you. This much less maintaining it to your new acquired studies in standards for the gear. Could be this technology coordinator is doing a perfectly fine job, could be and often is otherwise. You need to know the difference. Perhaps take a course at the local college or junior college in
stage lighting to supplement other studies of it. Gotta master beyond being able to function as it’s your responsibility this lineage and supervision.
Each
fixture if produced after like 1960 will have as if your coffee pot a stamp on it that lists it’s rated wattage,
voltage, manufacturer and model. That’s a good start. Take a list, heck,
pull down all the gear do a cleaning and service
call, figure out what needs attention and do a good inventory. When is for instance the last time the bolts on the C-Clamps have been oiled?
IN knowing what’s the right bulbs (Lamps - bulbs grow in the
ground or describe the shape of the glass on a lamp), you have to know what fixtures you have. AT times, a lamp will be larger, at other times say a hole in a
reflector is not sized for the lamp installed and say if closer than 1/16" to the
reflector, it’s not the correct lamp or you need to modify the
reflector. Another factor is
bench focus - that state when the lamp is correctly centered optically within the
reflector and
lens system. A lamp too close to a
reflector could also not cool properly and cause a
bubble or blow out if not explosion if torqued against the
reflector. Gotta do a
bench focus where possible each time with older fixtures, this if not at least a rough sighting of where the lamp is sitting in the
fixture by way of inspection after installed.
Lots of causes for what you have observed so far, you are the person on site. It’s going to take some
leg work and lots of study to
gain control of what you now are responsible for. Enjoy and live this time where you will learn ever so much. Ask lots of questions also.