By your hints, I’m guessing you have
Altman 360Q luminaries. I took some photos today that hopefully I will be able to post on my own.
First the easy on what needs replacement verses what to watch. The
Altman website like that of
ETC has exploded pictorial drawings in liking parts with photos.
The old reflectors are no longer available in having been upgraded. Rule of thumb is to use what you have until it burns up or is no longer able to become clean in reflecting well. At some
point there will be a seeming film on the older reflectors that just won’t come off. Stainless Steel/Aluminum Polish cleans reflectors well often beyond what glass cleaners can do, as long as it’s not a cream based pumas filled metal cleaning product that will scratch it. The new reflectors should take both heat and protect against what seems like ozone better.
Same with lamp bases. While you should inspect the lamp
base and lamp closely every time you change lamps to detect a problem, and have a spare
lamp cap/
socket assembly with
base and
plug readily available should one show signs of a problem, use the old lamp bases up as a cost effective solution than buy the upgraded 250c/1000w version. I don’t think that even the low heat normal bases will be a question of too small a
wire gauge for the wattage of a lamp as the case with a
ETC S-4
fixture that used 18ga
wire for the original ten year run of 575w fixtures before 750w upgrade. The
Altman bases should all be rated for a minimum of 750w. Such even original lamp bases/sockets if you don’t do much of any swapping of lamps between fixtures can often last years. I think it more a question of not well seated and swapping of lamps between fixtures that causes many to go bad. The old style
socket also needs to be watched in that it’s SF-2 silicone
wire conductors will often shrink/melt when over heated in leaving exposed conductors near the lamp
base assembly. The newest high temperature “TP-22" lamp
base in having 250c
wire, and rated for 1,000 Watts and with a added fiberglass spaghetti tubing over the conductors should have these problems solved and is worth the few more dollars more in investment. Got rid of the aluminum heat sinks and went with a engineered
porcelain to dissipate the heat instead on the high temp. premium sockets.
Other things to watch is the
yoke mount. If old style, keep a few replacement
yoke locks (die cast friction washers) in
stock if not possible to convert to the improved
yoke lock. The old
system is a bad design that easily breaks when people force the
fixture without adjusting the
thumb screw.
The below upgrade kit if afforded is a good solution.
[“The head assembly was modified for the 360Q in 1990. The old style was a straight yoke that used 2 die cast friction washers between the inside of the yoke and body, and two 5/16" T-Handles. The friction washers are available as #12-0012 and the T-handles are available as #37-0025. The yoke is no longer in production. Old style heads can be upgraded to the new style by ordering #95-0199 upgrade kit.
Included in the kit:
1) #95-0152 Yoke Assembly, 2) #20-0124 Locking Dog Discs, 6) Mounting Rivets, 1) Template, 1) Instruction Sheet.”]
Other things to look at is where the
lens train #70-0026 meets the
gel frame holding front #22-0129. I have seen a few instances where they have snapped this weld or the
bend that holds the
gel frame itself gets fatigued to the
point of breaking. Also look for stress fractures where the
pineapple / bell #12-0002
heat sink hinges to the
gate assembly #12-0132. Should it be cracked it won’t be safe for use in the inventory.
How to change the
shutter assemblies or if you need to at all.
Start by looking at the screws that retain the
gate assembly and testing to see if they show signs of rust or can easily be removed. If rusted or not easily moveable some “Liquid Wrench” on the hex head sheet metal or thread forming screws that hold the
gate assembly to the aluminum casting will be necessary. (Forget which type of screw is in use) This should be applied both to the inside and outside on the screws if stuck. Let it soak in to prevent the screw head from sheering off and leaving the screw body inside the
fixture.
Vise
Grip one at a time the fiber washer handles on the
shutter, and lock the Vise
Grip in a bench vise or have a friend hold it. Than drill out with a 5/32" or 1/8"#30 drill
bit all rivets that hold fiber washer to
shutter. Dependant upon the era of the
shutter. Start with either a #30 drill
bit or 1/8" and move up to the 5/32" to remove the fiber washers. Be careful in drilling because some times the drill
bit will either not stay centered on the
rivet, or can snag the fiber washer handle or
shutter itself in
whipping it around at high speed. Grinding away the rivets or breaking off the fiber washer than grinding away the
rivet is another option. Do not attempt to use sheet metal sheers to simply cut the
shutter blade, the steel is too hard for this.
Two of the four shutters won’t require removal of the fiber washer/handles to extract the
shutter, but it’s easier in general to just remove all fiber washers before taking apart the assembly. Some of these fiber washer handles if lucky when drilling them off might also be re-usable. On the other
hand there is about four different versions of this handle. The first has a 1/8" hole on it and fairly thin fiber washers. Second was 5/32" hole in the handle and thicker, a improved type similar to this and still available is a more thermoplastic type of washer for a handle with the
shutter sandwiched between. Finally I’m reading in the
fixture notes #14-0090 is a “single piece, molded finger
grip” - though I have never seen one. The original thin fiber washers might not work as well with more modern shutters. The purpose of saving old fiber washers would be for use as replacements to other fixtures. Either of the two more modern thermoplastic washer/handles will hold up better and should be used with new shutters.
Of note on these factory parts is that when you
purchase them is while the drawings imply it’s say a set of four, often you will only be purchasing individual parts - not a set. In other words, you not only need four shutters (verify this part is a set not individuals with the retailer) you also need eight thermoplastic washer handles or new style single piece ones and four 5/32" aluminum head & shank rivets from them also. I have gotten caught in the past by thinking I’m purchasing a set and only getting one piece.
General note on if the shutters need replacement or not. Discoloration of the metal in the
shutter is a first sign of heat, it than will loose it’s gloss like finish followed by the metal bending and burning away. If the
shutter is only discoloring, a fiber or even cotton buffing wheel can to some extent re-finish the surface of the steel to some extent that with a coating of graphite (below) can make the
shutter last a little longer. In changing colors it’s lost it’s temper and will not last a huge amount of extra time but will to some extent. In the other two cases, the
shutter is gone and needs replacement. All the pounding
flat and buffing in the world will not make it last significantly longer. At other times a
shutter will get a ding or
bend in it’s blade. It’s unfortunate and happens when someone attempts to force a stuck
shutter blade that has slipped between plates. Once the
shutter blade loses it’s
flat edge, that’s the
point heat will attack first in destroying the
shutter blade. It might be possible if a dinged blade to pound it
flat than grind a new
flat edge to the
shutter blade as long as doing this is before heat damage has been done to the
shutter and this grinding also does not cause heat damage to the
shutter. If doing so this new leading
edge of the
shutter blade needs to be perfectly smooth or those rough edges will retain heat or in melt faster.
Use a marker to designate a witness
mark for alignment of the ring for proper orientation upon re-assembly. Sometimes the screw holes otherwise won’t
line up. Now remove the #30-hsw0606-23 screws. Pull out one section of the
gate assembly at a time and replace the shutters with new shutters by pushing them into the center of the
fixture to remove. Any rusting of these parts should be sanded off than crocus clothed smooth. It’s a good idea to use a coating of spray graphite on warn pieces to coat the surface and provide a more frictionless surface. Be sure to let the graphite dry and wipe off the excess with a rag. Re-assemble possibly with new screws to mount the
gate. If your #20-0122
gate the screws thread into was aluminum, it’s easily stripped. If this is the case, turning it slightly and drilling than tapping new holes for it can be a good option.
Rivet the fiber washer or handles onto the
shutter blades using either 5/32" rivets provided by
Altman or aluminum shanked and body rivets. Steel rivets might provide too much clamping pressure upon riveting and cut
thru the handle.
The above Industrial Grade aerosol based High Temperature Spray Graphite or Military Spec. Dry Lube will also work well on
iris’s and
lens trains once both are polished with
crocus cloth which is a very fine sand paper. Again, the spray graphite needs to be applied in a heavy coating and needs to dry. The surplus than is wiped off.
Other notes on
fixture repairs:
Replace standard (McMaster Carr has most of them) screws such as sheet metal
and others if they show corrosion or it will get worse and destroy the metal
they touch. Re-tap holes in steel and add Teflon oil to them if meant to be
adjustable and to other working parts. (This might
smoke a little if the
vehicle in it has not dried sufficiently.) White Lithium Grease otherwise
works well for moving parts but once dirty needs replacement. Always use
Stainless Steel, brass or bronze in areas that it's going to get really hot
such as in mounting or holding up the lamp
base. Type 316 Stainless Steel while expensive is really useful as a screw grade for high temperature but
don't use it for lamp
base terminals. Don't forget the mica or fiber
insulators under the
base - they are important, if not also some form of
silicone or Teflon
insulator or pads under the screw heads mounting the
porcelain lamp bases to the
fixture. This will add a little
bit of soft
spring to the otherwise fragile
porcelain. Stainless Steel is not as good
for electrical
current - do not use it on contacts. Avoid Black Oxide screws
also - it's even worse for
current flow much less it does not take
heat/corrosion/moisture very well before rusting. As I found on the Mole
Lights, one would think that corrosion resistant Yellow Zinc Grade 8 bolts
will have done a good job in taking heat but they did not where they touched
aluminum. Plain steel if coated with either the
thread locker or Teflon oil
it would seem hold up better as a second choice to Stainless, Brass and
Bronze. For the lamp
base, as long as they clean up, the brass or bronze
screws are probably fine but otherwise are often easily replaced.
Purchase
of some Bronze external tooth lock washers to help keep terminals tight is
also a good idea. For other screws that need to stay tight but don't have
current, High Temperature
Thread Locker is useful.
Use High Temperature ring terminals on the end of the
wire and wrap it's
crimp barrel with high temperature fiberglass electrical tape to ensure it
can't short to something. If it otherwise has a set screw
terminal, use a
properly sized
ferrule on the
wire. This will prevent the set screw in
turning to apply pressure onto the
wire from cutting and un-even contact
with conductors. Where possible, if the lug the
wire is to go into is much
larger than the
wire, use more than one size of
ferrule. A 12ga
ferrule will
easily sleeve over that of a 14ga or 16 ga.
ferrule in not only better
sizing it for the hole, but adding a
bit more metal over the conductors to
distribute the pressure and further protect against the screw cutting into
them.
On the conductors themselves, 200c heat
wire such as SF-2 Silicone with or
without a fiberglass
braid over it should be used for anything over say
150w. For high output things without much cooling 250c TGGT teflon
wire with
a fiberglass
braid should be used. The primary difference between conductors
here to consider is that TGGT while it will take more heat is also less
flexible and might not be as good for use on a
whip. If looking at what your
fixture has inside of it and you see fiberglass
wire that's more tan than
colored white or black, it's probably TGGT in use. If the
wire is the same
as that of the
Luminaire cord than it probably is not unless on say a
cyc
light. There is also some 200c multi-conductor
fixture wire on the market
that dependant upon the brand will either be crappy and need fiberglass tape
reinforcement where it is touched by a
strain relief of if Rockbestos in
brand hold up really well and be much like a SJ cable. Adding a
bit of
fiberglass electrical tape at all strain reliefs in general no matter if fiberglass
conductor sleeving or multi-conductor cable will both prevent
much of the damage to the
cord because of the
strain relief and if say
1.1/2" extends beyond the
strain relief it will prevent flexing which will
also at the
strain relief cause cuts.
Fixture wire for large wattage
equipment often is and can be sized one size smaller than is normal for
amperage ratings on cable. Do not be shocked if you are working on a 2Kw
lighting
fixture and while 200c, it only has 14/3
wire feeding it for the
whip. Where possible in the
fixture use the proper
wire gauge however. For
750w rated fixtures it will normally be 16AWG, for 500w fixtures it can be
18AWG but I would also use 16AWG. (American
Wire Gauge.) Inside the
fixture
and on the way to the lamp
base, you will also frequently find some form of
fiberglass spaghetti tubing over the conductors. It can frequently be
re-used or is easily replaced especially with a silicone coated fiberglass
tubing. Good stuff in helping to keep the heat off the conductors. It also
where the cable is clamped to the frame helps prevent those clamps from
wearing into the wires. Where possible also in these areas some fiberglass
electrical tape will be useful in preventing this wear from inner
fixture
clamps.
Finally check them lamp
base contacts really well. At some
point it is
easier to just replace the lamp bases. In the Mole Light conversion project
you can see the difference between a good and bad lamp
base but they don't
have to even get that nasty to not give a good contact. Pitting once coated
when below the surface and not too extensive would be preferable to grinding
away at the oxidation which removes much more surface area than wise in that
entire area no longer coming into contact with the lamp's pins or
base. The
less surface area you have in contact with the lamp's pins the more heat
will
build up that could destroy pinch seals or even start arcing/melting
again on a lamp
base otherwise clean. In cleaning a lamp
base, want a smooth
mirror like surface as long as it's round or
flat sufficient to make good
contact with the pins. Should you need to clean oxidation or even material
left over from welded pins from the surface, and if you are able to get at
the contact area a Dremmel tool works well. Use a brass brush to clean the
base. Than various grits of abrasive wheels or tips to remove and hone than
polish the surface. Be careful not to remove too much material or most
especially too much material from only one area which will leave the contact
not touching the contacts on the lamp.
Crocus Cloth can also be useful to
refine either pins and contacts on a lamp or that of the lamp
base. It's
also good for working on
Iris and shutters. Some lamp bases and even pins on
lamps will have a nickel coating on them. It's not wise to remove too much
of it as it's there as a heat treatment.
Once you have a smooth mirror like surface without any scratches from
polishing visible (a small amount of pitting will be ok) you need to treat
the surface of the lamp
base or pins to make sure the freshly exposed metal does not oxidize. Some use normal de-oxidant and it works on lower than say
1Kw lamps, Some sware by Craig De-Oxit, others advise a copper based
De-oxidant, I use a McMaster Carr Electrical Contact Cleaner with Lubricant
that while not rated for the temperatures has been shown to work well and
without gumming up like normal de-oxidant will do on higher wattage lamps up
to and including 5Kw lamps. If using a
fixture with G-38 lamp bases (
Mogul
Bi-Post) and you have taken a lot of material off the lamp
base contacts it
might be necessary to use a thin copper foil wrap around the pin to make it
slightly larger.
When you lamp and test the
fixture, you should not hear any sparking or
arcing in the lamp
base, and both pins should have equal
grip on them. These
tips will in general work for most P-28s (Medium
Pre-Focus), E-26 (Medium
Screw), P-40s & E-39 (
Mogul of the two) ,
ferrule and R-7s (
RSC) based lamp
bases and lamps.
RSC lamps especially need lots of attention. Get out an
inspection mirror and flash light and have a good look at these pins when
servicing the equipment because the design in general is not that great.
Such a technique to inspect the wiring and bases of any
fixture in general
is a good idea to stop a problem before it becomes really bad. The earlier
you fix problems, the more chance you won't have to replace them.