Light Maintanence

8/18/2019 Light Maintanence

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Get out the inspection mirror and fash light. The ollowing is hopeully a useul

guide to a service call in general. Much o it has already been covered in other

parts o the orum, this is the details otherwise. Long winded but in ollowing

what to look or and watch or does not in servicing the equipment does not take

long. rint it up, then print up a poster si!e type o sheet with what basic

principals you are looking or. "emember that you are looking or problemsbeore they ail as the goal in a good service call. #leaning and prepping a $%ture

is one thing, do a real service call or inspection such as the rest o the world in

theory is doing yearly and it&s a by ar di'erent thing.

(irst the simple ) what is easy to notice without much work or the good service

call. Look at the $%ture, it&s cord and plug and note anything that stands out.

*hake the plug, do you hear it&s terminals loose within it+ oes it work+

-Look at the plug/s strain relie, has it ailed to keep the $berglass or cord/s

sleeving in the strain relie+ Look or suspicious stu' about the plug and the wire

coming out o it. Look at the pins and general condition o the plug. 0 stage pin,

are the slots in the pins parallel, with any plug ) did someone over spray the pins

with paint, are they arched+ 1ll would need repair than. 2ou can service a plug

but that&s a di'erent discussion.

3 4pen up a sampling o the plugs o given lot numbers and ensure that screws

are tight 5-67 turn past $nger tight or the speci$ed torque o the plug and

conductors are not warn or breaking away at both the strain relie and terminal.

0 you don/t have a way o knowing when a $%ture was wired, or it would be

di8cult, error on the side o opening up all plugs when possible during a good

inspection.

9a Make sure that those installing the conductor into the terminal knew what

they were doing in the proper amount o wire stripped and inside the terminal.

2ou would not believe how many wires have the insulator also inside the terminal

in now making good tension to the insulation o the plug but not so good tension

on the conductors. Much less loose terminals, or over)stripped :acket removed

rom the conducts and thus rats nest o wire within a plug. 4n a -;amp plug you

should see -67< between outer :acket o cable and the plug&s ace, on a 3=amp

up to >< but no more. id they get all strands o wire into the terminal or most

with a ew hapha!ardly finging about inside the plug+ 5it happens.

9b ?hat do the crimps or errules look like i stage pin plug+ id someone use

the wrong crimp tool or a pair o pliers to smash down on a crimp that later will

let the wire pull loose+ 0s the wire even correct in 1?G or the errule or terminal

in use+ @mm, double up a -Aga wire and it equals three si!es smaller in number

or three si!es bigger in dia. 0n other words, two -Aga wires equal -91?G. @eat

wire don&t old as neatly as copper thus you might in olding it to $t within a -3)

-=ga terminal or -3ga errule old it and it&s now $ne. 4n the other hand, a -Aga

wire stuck into a -3ga or -3)-=ga opening is about useless. More oten than not,

even when using a -3ga errule, the screw will still cut into the conductor and not

support all strands equally. 0 you $nd un)sae crimps or errules in use, and theconductors are damaged it might be worth your tugging e'ort in replacing them


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should they ail. Most stage pin plugs use a BC)93 screw. 1s long as you get a

ring terminal with a BC stud, there is a variety o ring terminal i not fag terminal

si!es based upon the wire not only what comes with the plug. 1 -7)-Aga ring

terminal will than $t the conductors properly as opposed to a wire that&s the

wrong si!e in the wrong hole. 4n a errule, use say a -Aga insulated errule, and

sleeve the normal -3ga errule over it. 2ou than get twice as much tin over thewire and much less chance the screw will simply cut thru the errule. ?ere your

plugs even installed with the proper crimp or errule hardware, or were

conductors :ust shoved into holes or wrapped around terminals+ Tinned wire can

be ok at times, but other than that, that&s why you are inspecting. on&t accept

crap wiring.

7 Look at the strain relie. ?as it too tight in damaging the insulation around the

conductors+ @as time and wear at this fe% point damaged the insulation or

conductors in this area+ ?as too much wire stripped and the strain relie is now

bearing down directly onto conductors as opposed to the sleeving or outer :acket+ ?as it too loose in causing problems with conductors breaking or pulling

loose o terminals+ Look at how much e'ect clamping pressure o the strain relie

has had on the outer :acket and or conductors. o they have the happy medium

or one e%treme o no tension or another o too much pressure and insulation

squee!ed dangerously out o the way+

; Look at the cord. ?hat kind o condition is it in+ 1re there little snags to it&s

$berglass that might e%pand with usage that you can glue back down in

preventing raying+ lyobond and other multi)surace adhesives work well in

preventing a small nick in the $berglass rom opening up urther. Deyond this,

are there large holes in the sleeving necessitating replacement o the conductor

protection+ (iberglass sleeving is cheap, replace it when it can&t be glued tight.

1nything larger or similar in si!e to a -67< hole needs replacement or cutting the

whip down in length. E%amine the conductors themselves at such holes. 0 *()3

with a $berglass braid over it, it might be rayed some but sae, on the other

hand it can also hide a scratch that e%poses conductors under the silicone

insulation. 0 other than $berglass braided conductors under a $berglass outer

sleeve, e%amine them also or what condition they are in. 4n the cord oten non)

braided heat wire will last longer, in the $%ture and near heat source, the

$berglass braided heat wire will oten be superior in heat refection. Dalance your

usage o a heat wire by what&s provided verses what you $nd most easy to use. 2ou are not allowed to have a splice within a whip. 1ny $%tures having splices

within the whip need replacement. @igh Temperature (iberglass Electrical tape

can at times work wonders or quick repairs to whips or work well in strain relies,

but should only be used i absolutely necessary to do a repair to conductors as a

temporary $%. Electrical tape is not rated or high temperature use nor advised

or use on a $%ture either conductor or sleeve to it. 0n most cases the *i!e B=

sleeve is the proper one to be using. 0s the sleeving in place too big, or plastic+

0 other than $berglass sleeved cord, you have some that are heat rated and

some that are not. 0n the good stu' ) at least FE that&s somewhat heat rated 0think to -;=c, or better stu' that will have a 3== or 3;=c rating to it stamped on


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the cable, have a look at it&s :acket and condition o the cable in general. 1t the

moment 0&m having some suppliers con$rm that their heat wire such as Tempfe%

or "ockbestos is water, oil 5og fuid and F rated or e%terior use. 4ten you will

$nd that heat wire cables ) in a rubber6silicone sleeve especially Euro FE types

will break down due to oil. amage to the outer sleeved cable than should be

e%amined or cuts and punctures as above and replaced as above. @eat in thecord touching a $%ture and other water, oil, and F can break down a cable in

making it unsae. F, oil and water can also break down a $berglass outer

sleeve.

Thermoplastic *HT wire is especially bad where oil rom og gets concerned.

1ma!ing how a little ();= fuid will break down a *HT cable. Much less, even i

I=c instead o J;c, it does not like to touch a hot lighting $%ture without serious

danger rom now e%posed conductors now touching the $%ture. *tage and *tudio

much less movie lights don&t use such cable ) probably not in the L listing or

application ) it&s :ust the cheap H club lights and 1" cans used or rock showsthat use the wire. #hecking with your local building authority on the KE# use o

such $%tures when powered by such cords might be a good idea. Even i a

actory aluminum 1" can, you might not be able to use the normal cord eeding

it on stage i they put any thought into the code. *o as with other ma:or or minor

pro:ects you might need to replace all $%ture cords o one type or another. 0 0

touch a $%ture, it&s really rare 0 will re)install a *HT cable on it unless really low

wattage thus heat.

Kot all brands o heat $%ture cable 5having inner conductors and outer :acket as

one assembly is created equal. 1ll will work to replace $berglass sleeved

conductors as long as you can attach them within the $%ture. ?hile Euro cable )

Tempfe% and ro #able amongst others might be rated or 3==# also, but it&s

insulation is poured around the conductors. 4ten a cut or nick in the outer :acket

than once fe%ed will go all the way down to the conductor. This as opposed to a

more *H seeming 1merican type o cable such as "ockbestos that has a separate

outer :acket with $ller material surrounding the inner conductors. "ockbestos or

heat wire cables is by ar superior. 1ltman and electrical suppliers can get it.

General distributors or gear more sell the Euro cable heat wire 0 less recommend

or use even i cheap and rated or the same temperature.

There is 3;=c wire, -;=c wire and 3==c wire. -;=c wire or other than use as aground is not recommended in line other than 1" $%tures :ust as a I=c *H or *HT

cable oten won&t be o much use. De cautious about $%tures wired by way o

e%tension cords, oten they are going to need a lot o work. (or the most part,

stick to the 3==c rated conductors, be it *()3 silicone $berglass sleeved or not,

or a 3==c rated three conductor cable. 3;=c #able while rated or a higher

temperature also most oten has less fe%ibility to it&s conductors and individual

strands o wire. 0n other words, while you can stick it in an oven and it won&t

melt down, day to day use and fe%ing on the other hand might break down the

conductors. 0nside a $%ture ) especially a Mole Light or 1udience Dlinder type

$%ture and other $%tures o very high temperature, you can&t do better, but as a$%ture whip you can. 3;=c wire is most oten Tefon instead o silicone and when


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available as a cable it will have a sort o varnished $berglass sleeving over the

cable. Good stu' or permanent install, :ust don&t bend it with constant use.

o not be overly concerned i your heat wire seems less in 1?G rating than that

o a normal e%tension cord. ?hat are these 3,===w (resnels doing using -769

wire on them+ @eat wire by it&s nature will be a little less e'ected by heat inamperage rating due to it&s higher working temperature. 0 that&s what the

manuacturer speci$es to use, it&s use is correct. 4n the other hand, some

lighting $%tures such as the ;J;w version o the ET# $%ture came with -Cga

wire. 4nce they came out with the J;=w version, the -Cga wire was insu8cient

or the wattage. 2ou must in using a ET# $%ture at J;=w be using the proper

conductor si!e. ?hile or all other intensive purposes the $%ture is one in the

same and on the really old versions you can get rid o the alignment nubs

speci$c to the ;J; $%ture in installing a J;= cap on it, you must change the

conductors. *ome heat wire you can use or over it&s thought to be e%pected

amperage, others you don&t want to be using. "ead and ollow the $%tureinstruction manual and guides on them.

@ave 0 mentioned the use o an e%ploded pictorial o each $%ture you are to work

on in being useul+ Go to the website and pull up the assembly drawings. This

will both save time should you have to pull a $%ture apart in re)assembly, and

help you to know when someone did a other than actory improvement to it.

2ou should have a three ring binder in the service area o the instruction manual

and e%ploded pictorial on all $%tures in use.

A @ave a look at where the cord now enters the lighting $%ture. That&s another

fe% point that oten will wear out both or outer :acket6sleeve and inner

conductors. Deyond that what type o strain relie is in use+ 0s it a two screw

strain relie that oten cuts into the conductors, a nylon strain relie that becomes

brittle and has too small o a cross section in rubber water tight strain relie to

take heat well without becoming brittle or a metal one that&s more substantial in

taking heat better but can still slip or allow the cable to slide ree. 1 @eyco nylon

strain relie oten will need to be replaced. 1 two screw strain relie i cutting into

the conductors or sleeving might require you to replace the whip. (iberglass heat

tape will be a good abrasion and fe% resistant $% to such strain relies. 4therwiseproperly si!ed nylon tubing while it&s hot will oten last well in a $%ture in limiting

the fe% and clamping pressure. 4n a nylon strain relie you will oten $nd that i

the nylon shrunk, became brittle and cut or moved, the little nylon $ngers than

clamp directly onto the cable and it than is dangerous. The tape will also help in

this area.

J The strain relie itsel, is it loose+ Especially with plastic strain relies, they

come loose. 1 loose strain relie than will allow conductors to twist, move and

pull ree. That&s a bad thing, the conductors should not move about within the

$%ture other than where needed while ocusing the lamp. Get the strain relie

tight by hook or by crook 5rivet or other method, and when e%posed, add hightemperature Thread Locker to it to keep it there.


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C (ollow the wire rom strain relie to lamp base within the $%ture. ?here

e%posed such as in a lamp cap, have a good look at it to ensure the conductors

don&t stretch or overly touch anything such as screws or anything else that can

cause bad cooling around it or pull tighter as the $%ture gets ad:usted. 0t&s

common conductors will pull some with use, make sure that you both have slack,

yet they don&t touch what they should not in having too much slack. 0 you can&tget e%posed wire in direct sight, use the fash light and mirror as necessary.

0nspect every inch o the wire. This especially near the lamp base as it&s the

most concentrated source o heat and oten where the wire will start to ail. 4ten

in a $%ture you will see $berglass sleeving called spaghetti tubing over the

conductors. That&s a good thing both to protect rom wear on things it might rub

up against, and shield some against the heat. 0 nothing else, where cord enters

lamp base, a sleeved wire should it ail than has the e%tra layer o protection.

That&s also the general concept o $berglass outer sleeved silicone wire as

$%ture whip. *hould you be replacing whips or doing work in them, sleeving the

conductors i not the high temperature tape is oten useul.

I *ome $%tures such as a 1" can will oten have a splice inside the lamp cap

that goes rom heat wire o' the lamp base, to what ever type o cord is used.

4ther stage and studio cans will :ust use longer leads in a $berglass sleeve ) a

better idea. 4ther $%tures will have au%iliary gutters mounted to the $%ture that

are slightly cooler to house things like switches, circuit breakers or uses, i not

:ust patch the wires.

4ten the splice will be $ne, other times it can use improvement to it ) even i

actory. Hust opened up a 1ltman #M outdoor par today. 0t had 3==c wire coming

o' the lamp base, 3;=c cord o' the $%ture, and I=c household grade wire nuts

binding the conductors. The $%ture itsel in only being -;=w arc source can get

hot still in it being an arc source, but the wiring cavity where the wire nuts were

in use were separated rom the heat both by way o refector and secondary

plate covering this cavity. 0 was less concerned about heat ) though questioning

the use o vinyl wire nuts, and more worried about the wire nut coming loose as

oten wire nuts will due to vibration or :ust use.

o not allow standard wire nuts even in such a $%ture. Kylon, Finyl and F# all

have the same sae operating temperature so don&t be ooled by nylon splices

either in being better. rimary di'erence is the other two melt in e%posing theconductor, nylon :ust becomes brittle and as a secondary thing needs to break

away beore it also e%poses conductors. My choice in this instance where heat is

less a actor will have been to use something nylon.

*peci$cally 0 will have used nylon cap splices that are like a wire nut, but you use

a crimp tool to crimp the thing into place so it won&t come loose in e%posing the

conductors or letting them pull ree. 4therwise there is lots o high temperature

wire nut solutions that either can be hi)temp tapped so they can&t pull loose, or

have internal set screws over high temperature plastic outer coverings. epends

upon the application.


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?hile a splice within a $%ture is preerable to within the cord, it short o having it

&s own area is oten dangerous. Look at rock and roll par cans. There is a good

reason why the spin the bottle hole is oten capped o' or there is a knob to do so

now. Most o it comes rom the splice method and cable. 0n the past this was

made especially hard since oten you needed the same 1" can to run 1#L in

series, "ay Light with wire leads eeding it, and 1" #an lamp with it&s MogulE%tended End rong base. M4E or GN)-Ad. Given you had to switch, easy to

remove methods rom spade terminals to using the wire nuts has been done in

the past. Kow 0 high temperature splice and high temperature water proo heat

shrink tubing over the crimp terminal i not replace the whip. Ensure that

especially i *HT cable or lower rated cable, that the $%ture whip is not touching

the lamp or metal components within the $%ture. 1ir is the key.

0 you have a splice within the $%ture, note the conductors going into it to see i

e%posed conductors are alling out o the splice or i it all looks neat and trim

with the insulation stopping shortly beore the crimp or turned area but de$antlynot e%posed. 1re conductors able to pull out o the splice, are there strands o

wire not quite going all the way in, is the $berglass sleeving becoming loose+

Lots o other details you will note up to and including a strand o wire melting

thru the wire nut. o not use vinyl wire nuts within $%tures )replace them i you

see them or they will work loose and allow a short. Ko matter the conductors,

don&t use something that can come loose. 1nother type o splice is the push in

terminator6tap splice. *uch things work well with solid wire, but it&s oot grip

otherwise will cut thru stranded wire. 0 you have stranded wire going into a push

in to grip type o $tting such as used on some stereo equipment speakers,

replace it as it&s not dependable. ?here possible cable tie in a par can wherethere is a lot o cooling vents, or use $berglass E)tape to band the wire together.

This will take up most o the strain relie rom the splice, make or a neat splice

and prevent the conductors rom moving where they need to be spliced. Oeep

the tape6cable tie away rom the splice so you can see into the splice. 4therwise

when you hide the splice by way o tape, it makes those later seeing it suspicious

as to what shotty work you are trying to cover up such as too much stripped

insulation o' conductors e%posed.

1nother type o splice would be the butt splice. @igh temperature butt splices as

long as covered in at least three layers o high temperature tape, or in the case

o a par can ) high temperature heat shrink that&s water resistant is an option.1lways use the correct splicing tools and give a good tug on your wires ater

splicing them to ensure you have a good splice.

-= #heck the ground. Ground conductors can be using lower temperature wire

in that they don&t touch the heat source directly, and one would preer to note a

melted ground as a warning sign or the rest o the $%ture, than have something

else ail in melt down. They oten will also be a lower gauge o wire in some

belie that the current fow temporally in overload thru them will be su8ciently


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able. That&s a actory consideration. ?hen replacing a ground wire, use the same

gauge o wire as the conductors.

1 melted ground wire, or e%posed crimp to it is not a bad thing in all cases. 2ou

don&t want such a thing where it can touch terminals, but the idea o a ground is

that a hot will touch it or the rame $rst anyway so why insulate it+ 1rchitecturallighting $%tures oten won&t use a insulated ground wire. 0nsulate where possible

but don&t be overly interested in over insulation o it as opposed to a conductor.

#heck it&s crimp terminal. 0 it&s all burned up, use a high temperature crimp

terminal instead. 0n general, use high temperature crimps and splices anywhere

inside the lamp base area. "eplace where o%idi!ed and corroded ) you want a

good ground path.

-- #heck the mounting o the ground. That wire should not be able to move

about or twist because this also means a less than sae connection. 4n a 1"

can, that riveted ground will oten work it&s way loose. *ame story on a real$%ture. The ground will oten come loose no matter i rivited or screwed. 2ou

cannot use Lock Tight or Thread Locker on conducting screws thus it won&t work

here ) it needs to be all mechanical. 0n the same respect you also should not be

using nylock nuts. Think about nylon verses heat ) a nylock nut inside a lighting

$%ture oten won&t hold tight in the long run. 0 necessary you can re)pound a

rivet back to tight as a temporary $%, but otherwise need to replace it or better

yet go with a screw.

1lways a lock washer. Dut instead o the spring lock washer types, use a internal

or e%ternal lock washer or better gripping o the conductor. 2ou can use lockwashers with rivets. This especially i what you are grounding to is painted. aint

don&t conduct well thus some orm o displacement o material lock washer

between crimp terminal and paint surace can be useul in it both preventing the

terminal rom moving about and in digging into bare metal.

1 good lock washer and nut will work at times better than a nylock nut. Try to

avoid washers where your ring termials are concerned. They :ust act as a pivot

easing surace in urther loosening up the :oint. 1 e%ternal tooth lock washer will

both unction as a washer and prevent it rom coming loose. Deyond this, a

toplock nut will both take the heat in mechanically being hard to loosen and add

to the resistance o the nut coming loose.

-3 Look at the lamp base where the wire goes into it. 0s the wire showing heat

damage+ 1re the screws i used to mount wire to lamp base loose+ o they have

a lock washer+ 1re lock washer and screw brass or bron!e+ 1 belleville or cone

washer will otherwise be acceptable as long as the same metal. *teel tends to

corrode and stainless has at times problems with touching other metals such as

brass and bron!e in otherwise causing corrosion problems. Pinc plated steel once

in a lamp base will corrode very easily ) avoid it&s use. 4n a lamp base, a

brass6bron!e and perhaps only as one o the two in nickel plating will su8ce. 1re

the crimp terminals showing heat problems such as corroding+ "eplace in thatcase with high temperature terminals and insulate them as needed with high


8/14

temp. tape and tubing. Kothing other than the ring should be esposed. 0 (resnel

or Medium re)ocus 5)3Cs base, there should be an insulator between lamp

base and it&s mount. 0s it in good condition or all brittle and burned up+ @ave the

conductors ailed in getting too hot+ E%posed corroded conductors coming o' the

lamp base+ This can be because o loose screws or other arching sources, or :ust

heat in general. #ut and replace as needed. se spaghetti tubing and a smallamount o tape as necessary.

-9 Look at the lamp base mounts. 1re they tight+ 1s above in using lock

washers and i needed high temperature Thread Locker will also help. Most

important is the metal type. 1gain brass and bron!e in taking heat well,

otherwise stainless steel in also taking heat well i not better ) :ust not

conducting as well. Even on a 1" can lamp base, how about that screw holding

the plates together in it&s being tight+ *hould your wire eed into a hole in the

base mounting plate, what kind o condition is it in and is that hole a sharp edge+

Tape, a silicone panel washer or something to make it work better+ 4n otherlamp bases such as mogul screw or medium pre)ocus internally, be it rivet or

screw are they tight+ *ome are designed to have a bit o movement, study the

type o lamp base or what&s best but don&t accept loose where not appropriate.

-7 "emove the lamp and inspect its& contacts. 1re they actory or arched and

corroded+ 1re they nickel plated as per new or or the most part clean but

blue6black+ ?hat the lamp when it&s taken out as need be with a pry bar says

about itsel, it also says about the lamp base in contact with it. Gold plating is

great, but also melts down. 4therwise nickel plating is normal. E%amine any

center point contact plates also. ?hile a screw base to a 1)lamp6household lamp

might be nice and neat, oten that center contact ) that should be the hot will get

really unky. 0s it a smooth surace without bumps and divots rom welding+

Especially bad will be "*# 5")Js lamp base types that have a sort o cone

contact on each end o the lamp. They :ust don&t conduct well in tension and

surace area to conduct with. *urace area ) clean surace area is the key to

conduction. Dlackened and arched lamps in base will have less path o least

resistance to conduct with meaning lots o heat and e%tra heat at those points

that conduct better. 2ou can clean lamp base contacts but that&s a separate

discussion.

"e)install i in good shape the lamp. 4n a 1", can you physically lit the lamp byit&s base, or does it :ust all out+ 4ther lamps and bases will have similar

relationships rom bi)pin to "*#. 0 that lamp easily gets removed, one bounce

while installing or transporting it will also allow the lamp to become disengaged

rom the base. *uch loose contact will also be a source or e%tra heat as the

current tries to fow but has less than optimum tension. Take the lamp back out.

-; look at the lamp in general. *ome types will have porcelain around the pinch

area. *ome will even have a layer o silica sand between pinch and porcelain.

That silica sand with a crack allowing it to run right out o the lamp base than is a

bad thing. 0n other lamps, perhaps i the two part porcelain is loose such as in a


9/14

;Ow 2 or larger lamp, perhaps more support such as a stainless steel hose

clamp will be necessary to keep the two piece lamp base together.

Look at the lamp itsel. *ee any white $nger prints or buldges+ Much less look at

the lamp $lament and it&s supports. Lamps are another discussion as to what

you in inspection can live with or need to note in replacing. #lean the lamp withde)natured alcohol and a lint ree cloth ater looking at it. *uch alcohol will also

let you e%amine the $lament o a outside rost lamp such as in the case o a (#M

cyc light double ended "*# lamp. 1s long as you are able to look thru the

rosting to the glass, you might as well look at the $lament.

-A ?hile the pins o the lamp, and the lamp in the base tension is important to

note, during a real inspection you need to pull out the fashlight and inspection

mirror. 2ou are e%amining the $%ture, so why stop when it&s something you can&t

easily see+ Granted a G)7 up thru G)I.; base such as a (LO6(EL will use will be

hard to see the sockets, but give it a shot. *ome types o base are servicable

5again as a separate discussion others once they show wear such as blackening.

Lack o tension and pitting need replacement. 1lso throw out the lamp unless it

can be saved with work. *ome older versions o (resnel lamp bases allowed the

center contact to un)screw some. *hould it not provide correct tension, you could

screw out a little more to some e%tent in making it a tighter $t within the socket.

Most modern bases won&t do this. 1 edison lamp base on the other hand has a

center contact that i not providing su8cient contact can be bent outbound to

provide more spring to the contact point. @ave a look or arching or discoloring at

a speci$c place on the lamp base ) this will tell you where the lamp to base

either makes it&s only contact or no contact. ?here possible to service you lamp

bases it can be done, otherwise at very least a cleaning with perhaps a thinned

out cue tip and some carburetor cleaner will work wonders in removing carbon

build up and o%idation. 0mportant to note is that once you have a bu'ed and

serviced surace, or at least one that&s chemically clean, you need to coat the

now bare metal or it will o%idi!e worse than i you had not touched it. There is

various de)o%idants and coatings on the market discussed elsewhere also.

-J Electrically now your $%ture should be in sae condition. There are potential

other notes 0 orget in general or that the manuacturer might state. *peci$c

$%tures also have certain details about them. Mark your $%ture in some way with

the date and your name. erhaps grease pencil or marker inside the lamp cap orsomething. That&s a good tracking and quality control type o thing.

-C (i%ture itsel. (ollow the manuacturers instructions or how to clean the lens

and refector much less bench ocus it. There will be di'erences in style

dependant upon the brand and type. *uch things also have already been

discussed.

-I Dlow air into and all around your $%ture with the lamp removed beore you

clean refector6lens. #lean the $%ture with ?inde% or other non)residue

chemicals. 4therwise give it a second alcohol cleaning to remove the residue.

Kote that resh rags are a good thing. Look or rust. "eplacement o bolts,tapping and oiling with a oil rated or the temperature i not tightening them and


10/14

using thread locker will be needed now. aint as needed the $%ture now that it&s

disassembled or the most part. De careul with some o the screws that are

stuck. (or many o them they will break or strip beore coming loose. 0n cases like

that, you have to replace them to the best e%tent possible. (rom gel rame clip

that comes loose or un)welded to lamp base knob that does not screw in easily,

now is the time to check each part and $% them.

3= @ave a look at other pivot and working parts such as the yoke mount. 1re it

&s screws6rivets tight or loose+ 0s the locking dog or clutch in good shape and not

broken or loose+ "eplace especially the yoke mounts now as opposed to later.

Most will use ;6-A< grade 3 screws. These oten rust with heat and moisture.

Detter ones are availiable. The area o the yoke is oten what needs replacement.

2our $%ture should not slip out o it&s ocus even when locked into position

without dogging down. 0 it slips, there is a cause. #an be as simple as turning

the carriage bolt on the clutch mechanism I= degrees or it could be something

stripped, broken or loose. @ave a look at the non)clutch side o the $%ture. 0s itstripped+ 0 all such as on a par can that side is attached to is a aluminum plate,

it&s easy to strip this out. erhaps a longer screw with side lock nut to prevent it

rom coming loose ) but not so tight it gets in the way might be o value. *uch a

nut might also be o use on the knob side o the yoke. "emember the alling

ollow spot issue. 0 you can&t remove the screw, it won&t all. 4ten on a 1"

can, the screw will come with a nut on the inside o the can. 4ten given this a

nylon locking nylock nut. Great idea in preventing the screw rom coming loose,

bad idea on the nut type, much less given you can&t see the nylon not ailing

how do you know it&s still there+ 4n a 1" can, what i you were to eed the

screw rom the inside o the $%ture and put the nut ) even i nylock now that it&sless in the path o the light, on the outside o the $%ture+ 1t that point a missing

nut hopeully is noted.

3- @ave a look at the lens train or ocus operation. oes it&s rails or slot need

tefon oil, white lithium grease or spray on graphite ater removing any rust+ @ow

does the lens train move about+ 0s it easy and smooth, or do you have to kick it

to get moving+ (irst sand the lens train with say -== up to A== grit paper, than

as needed add the spray on graphite coating and wipe o' the e%tra. 2ou will be

surprised as to how well it works than.

33 #heck to ensure your lenses are clean and not chipped in any way that wille'ect the output. 1re they green or blue+ 1re they the same type o lens as the

other $%tures, much less in the correct mounting holes+ #lean the lenses say in a

dish washer amongst other debated solutions. 1lso make sure that the proper

lenses are both in the proper order in the lens train as there can be more than

one si!e in one lens train. Much less at times lenses while or the same $%ture

can have been upgraded to a wider but thinner lens. Make sure that i you are

buying new lenses that you state how old your equipment is.

39 2ou have drawings, look or the missing parts rom a cone washer replaced

by a lock washer to a $ber washer not used at all. #heck the condition o the

parts on the $%ture. Look also hard or loose and missing asteners i not cracks


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in the rame. 1 crack in the gel rame casting can be a bad thing. 1 crack

elsewhere might be acceptable.

37 *hould this $%ture have an iris, what kind o shape is it in+ erhaps crocus

cloth and graphite will help it, or do some o its leas need replacement+ There

are only a ew di'erent types o iris leas and they are interchangeable or themost part other than i one o the three. 1 Lycian M3 ollow spot lea is the same

lea as used on a 1ltman 9.;Q; $%ture. 4k, such a iris base $%ture does not e%ist

but 0 own one. *o i you have a bunch o burning up iris units, perhaps you can

buy one and change out what leas are needed, than clean the rest. 1 iris

burning up in one area more than another means a badly centered lamp but it&s

too late now.

3; *ame with the shutters, as long as they are not bending inward, you can to

some e%tent sand with very $ne sand paper, i not even grind a new smooth

edge on them that&s :ust slightly shorter in re)using them as long as they are fat

and smooth. This is a very speci$c technique 0 will inrequently use but or the

most part replacement shutters are not that e%pensive. 1s with the iris, what is

most important is a smooth fat edge to the surace. 0 it has even a ding in that

edge, that&s where heat will concentrate in making that shutter ail. *hould be a

given that i you have to have a shutter in more than say 7=R rom one side,

that perhaps you should re)ocus the instrument, but what ever the case, look or

heat damage because not everyone thinks. *ome you can save and graphite,

others you need to replace. Each brand has a di'erent means o getting at the

gate6shutter assembly. Much less or instance on the 1ltman 9A=q series, it&s one

o three types o round washer like handle and a speci$c rivet. se the wrong

rivet and you might wreck that washer.

3A #heck the refector, gate and other parts o the refector assembly or rust in

mounting or plate or rust on screws. *hould the $%ture get wet, that rust will

seep onto suraces and destroy them urther. These ater the lamp base and wire

will be ne%t to get hottest. 0 you blow out your $%ture and get a shower o

micron si!ed silver conetti, you know that you have a dichroic coating on the

refector that&s peeled up. 1s said, ollow directions in cleaning refector and

lenses. se the wrong cleaning method even on a 1l!ak aluminum refector and

you can destroy it. 4n a ; or -= degree Leko&s plastic lens, that glass cleaner

might :ust scratch it worse than :ust using alcohol on it to wipe o' the dust. 4nthe other hand or say the inside o a scoop, perhaps a resh coat o high)heat

refective or white paint will do it wonders when not so nice in $nish.

3J (i%ture or the most part is done in a thorough inspection. 2ou don&t have to

$eld strip the $%ture, but checking as much as possible even with one&s $ngers

to veriy tension is o use. 4bserve everything, than re)assemble, turn it on and

bench ocus. "emember that hot patching is a bad thing. 0nstall a in)line switch

instead when protected by a G(#0 outlet. i'erent methods or the bench ocus

and another debate.

3C #heck the saety cable. There should be no rust, much less that snap hookneeds to snap shut. 0 it does not perhaps a bit o oil will make it do so, but don&t


12/14

spend too much time in making it snap. #ut up and replace saety cables that

don&t snap closed. "eplace snap hooks also that don&t close properly or that

have broken teeth to them. There is a debate urther in i it&s permissible to bend

a saety cable&s loop to $t thru a >< hole in the $%ture. *uch a bend than

becomes a weak point in the wire rope, but given the distance o all, it&s

probably not un)sae enough. Hudge or yoursel and look or broken strands orseriously damaged bends or wire rope in general.

3I The clamp is oten neglected. ?hy do actory send a >)-9 grade 3 screw

that&s only 967< long with the $%ture+ @mm, loose -6C< worth o lock washer, and

another -6C< worth o yoke and that&s only >< worth o thread within the #)

#lamp. Kot enough nor a strong enough screw in my opinion. Even i J6C< or -


13/14

clamp to the pipe, they will deorm the tip o the bolt. ?hen you try to remove it

rom the clamp, the bolt oten is harder than the cast iron o the clamp and it&s

removal will destroy the threads o the clamp. That&s unsae. *hould you have a

damaged tip, re)tap, or cut it&s tip o' than re)tap. Then e%tract it. *hould it be a

bent bolt, cut it o' at the bend and remove what you can near where it e%its the

clamp. 1ttempting to remove a bent screw rom the clamp otherwise will alsostrip out the clamp. "eplace with the same brand o set screw.

0n assuming a #)#lamp, the technology o the casting has improved much over

past years. They still are not perect. 0 your clamp no matter i bent steel, cast

iron or stamped or cast aluminum shows any sign o bending, replace the clamp.

o not allow in service a bent clamp. ?hile more requent that it will bend

instead o break, you still don&t want to continue using it or it potentially will

break.

De watchul o stock looking cast #)#lamps that have a sort o pint6varnish

coating on them. They do not come rom any manuacturer and instead rom

china. *uch clamps that have this seeming varnish coating are using much

cheaper metal in the casting and need that e%tra coating to prevent the rust.

*uch clamps with the cheaper metal will break and strip -=% aster than anything

a name brand even 7= years ago was making. 0t&s also something that should it

get hit might ail instantly at any point. @ave a look at the clamp or hair line

cracks, but with these cheap #)clamps you might never see the hair line clamp.

o not use some o' shore other than name brand clamp. Ko name on the clamp,

varnish like coating to it, toss it in the trash.

*uch clamps came on the market say -= or -; years ago and only lasted a ewyears by way o the theater supply market looking or a cheap alternative. 0

doubt they are still available, but thousands have been sold over the years. De

watchul o such things.

9= #E verses L $%tures. De mindul o the world economy. 1t one point we had

a delivery o a hundred or more *)7 1" $%tures come in on a rush order. They

were all metric we ound out later. 4ver -,7== *)7 1" $%tures in stock, and

other than some sold o' and replaced over the years, the metric *)7 1" still

shows up in the inventory at a constant basis. *ubstitute a M )7 or a -=)93 screw

and you have serious problems. Take the clamp o' and try to install it on another$%ture and you now have a standard >< screw $tting into a metric clamp. "ock

and roll aluminum 1" cans and their clamps are phenomenal in having any

number o three ) yes three types o hardware in them. Metric, *tandard and old

English *tandard. Think back to the history o #hina and the orient. 0 industry

was set up during the turn o the century, they in being backwards but catching

up might still be using some say antiquated >< but -3 instead o -9 threads per

inch screws. Think about the possibilities o such hardware getting into your own

inventory. ?hile you can or the most part i you know your asteners tell the

di'erence oten between a metric and standard piece o hardware ) or instance

the black o%ide type asteners when metric will have a sort o gloss coating to

them, once you get something that is imperial but the wrong thread in being


14/14

very close into your system you are screwed. 4r or us the shop manager that

made the choice to not instantly toss out all that hardware screwed us. 1 bolt

might be a bolt in saving money, but once it&s mi%ed in with other bolts you are

screwed. Many metric asteners will be very close in threading to that o a

standard thread. Hust a wee bit loose or tighter than normal. De very careul

these days and get your theater to purchase screw thread plates to test themwith.

Deyond this, should you get a $%ture that is metric, take a engraving tool and

write metric across it&s body so those looking to SBC33=$%SBC33- it don&t

make it worse. De very careul about the hardware that is on the clamp or

$%ture. Fery easy to screw up and ruin your world.

1 simple, thirty step process anyone can do in his6her own theatre.

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Light Maintanence