Atlantic Illumination Entertainment Lighting

AIEL Shop Tips

PAR LIGHT OVERHAUL

(Image Left: PAR 46 Stage Light)

    Although somewhat supplanted by LED fixtures, the PAR remains a basic lighting instrument in the entertainment lighting world, especially for smaller productions. Its low cost, simplicity, light weight, variety of sizes, high light output, and its long life are appealing to many lighting personnel in the industry.

Instructions here will guide you through the
procedures to overhaul typical PAR fixtures.



INFORMATION BELOW MAY
NOT BE REPRODUCED
WITHOUT PERMISSION
FROM THE AUTHOR ©

Be aware neither Atlantic Illumination, nor its owner
and employees will be responsible for any problems
encountered as a result of following or not following
the procedures here. This is only a guideline. You
must decide the suitability of the steps given, and
be responsible for the results of your own work.


  Topics

PRELIMINARY


Disassembly


Inspection


Reconditioning


Washing


Electrical


Painting


Reassembly


  Electrical Testing


Alignment

Final Procedures



 

  Preliminary

PAR maintenance is the simplest of the lot, because this light
is simple by design. It typically consists of an outer shell with
a yoke, accessories holder, and lamp access. Internally are
the electrics and PAR (Parabolic Aluminized Reflector) lamp.
The fixture itself has no reflector or lenses because they are
part of the lamp, although models exist with each component
being separate. LED units in place of the lamp, have a plate
upon which red, green and blue LEDs are arranged in rows.

Instructions given will lean toward the PAR 46 and larger
models, although some text will reference other designs.
Modify the procedures as required to fit your fixture type.

Read through this article before starting so you'll have an idea of what is required and the tools needed. You may find that some procedures are better done out of order for your particular model.

    Regarding the refurbishment itself, this article assumes that the fixture is to be completely overhauled. However, you may require to do only a part of what is detailed here, so simply skip to the pertinent section(s). Read through them before starting so as to perceive what will be required. You may find that some steps are better done out of order for your particular light or way of doing things.

    If you are unfamiliar with the model you have, make notes or drawings, or have an assembled fixture available for reference. Otherwise, given the simplicity of the PAR fixture, these will likely be required only if you are completely new to stage lighting fixture maintenance.


Before starting the procedures, determine
which of these items to make available:

  • Replacement Parts
  • Alignment Cradle
  • Alignment Screen
  • Test Dimmer
  • Newspapers
  • Heat Shrink
  • Heat Gun
  • Small Parts Bottles
  • Large Muffin Pan or
    Parts Containers

  • Bench Vice
  • Bench Brush
  • Screw Drivers
  • Nut Drivers
  • Diagonal Cutters
  • Locking Pliers
  • Wrenches
  • Knife
  • Fine-Toothed Flat File
  • Narrow Scraper Tool

  • Rubber Mallet
  • Crimp Tool
    and Connectors
  • Electric Drill
    or Bench Buffer
  • Drill Bits
  • Rotary Mini-Tool
    (Optional)
  • Variety of Wire Brush
    Attachments (Brass)
  • Cut-Off Garden Hose
  • Plastic Soap Pads
  • Steel Soap Pads
  • Scrub Brush
  • Tooth Brush
  • Dish Detergent
  • Emery Cloth
  • Sanding Sponge
  • Fine Steel Wool
  • Spray Paint
    (Heat Resistant for Metal)
  • Paint Solvent

  • Masking Tape
  • Cardboard Mask
  • Rayon or Cotton Batting
  • Glass Cleaner
  • Methanol Alcohol
  • Distilled Water
  • Soft, Lint-Free Tissues
  • Penetrating Oil
  • Lubricating Oil
  • Oil Station Bin

  • Paper Towels
  • Silicone Lubricant
    (Industrial Grade)
  • High-Heat Wire Nuts
  • Rags
  • Permanent Marker
  • Electrical Tape
    (White and Black)

    Set up a work space with proper lighting and the tools required. Refer to our Work Area Setup article to help with this. Provide a muffin tray or containers into which the parts from each disassembly step wil go; number them. This will be a benefit when it comes time to reassemble the unit as the parts can be selected in reverse-numbered sequence. Lay clean newspapers on the bench to protect both it and the fixture, and to contrast with small parts that might get dropped during the processes that follow.



    Now begin the overhaul itself:  

(Image Left: Screwdriver)   DISASSEMBLY

    A reminder that if you are new to this to keep track of the
disassembly by making notes. Use the numbered containers
or muffin pan to hold the parts removed during each step,
and have an assembled fixture available for reference.
Now do the following:


  1. Position the Light:  With a room-temperature fixture, first place it on the newspapered bench in an upright, face-down position. Most have a lamp access door at the rear. Open this. Be cautious: Some poorly designed fixtures only secure the lamp via this door. Opening it may send the lamp crashing to the floor should the fixture be in any position other than face down.

       If the fixture is smaller than a PAR 46 or is an LED model, it will likely need to be placed horizontally on the bench so that there is access to the lamp or LED element plate.

  2. Socket and Lamp Procedures:  For the smaller PARs, unscrew the lamp, or remove/unlatch the retainer to access the lamp for removal. Some will have separate reflectors and lamps that are retained by clips or a ring. LED models will need to have the LED element plate removed, usually via screws around its perimeter.

       For most PAR 46, 56 and 64 units, carefully pull the socket free from the lamp's connectors. Hopefully, it won't be seized. If it is, you will need to turn the socket and lamp in such a way that penetrating oil can run down into the socket. Let this sit for a while and then attempt to disengage the socket again. If it's completely seized and the socket is one that is bolted together, unscrew these bolts and separate the socket halves. You will then have to work to release the contacts from the end prongs of the PAR lamp.

        If they have become welded together, be prepared to possibly have to destroy the lamp, the socket, or both. This is particularly so if the socket halves are riveted, although you could attempt to drill out the rivets. If you must purposely break something, try to save the more expensive lamp unless it is burnt out.

        Now take out the lamp. This is done either by holding back a release while the lamp is lifted, or a retainer ring must be squeezed and moved past nipples on the inside of the lamphouse. Then the lamp may be removed. LED plates and some lamps come out the front of the fixture after removing a clip or a series of perimeter screws. Place the lamp in your safe place, as discussed in the Work Space Design article.

       During this procedure, don't be worried about touching the bulb. You will be cleaning it later.

  3. Yoke Removal:  You may prefer to do this step before the lamp removal, which is fine. Just be sure to protect the lamp from damage. With some models, the removal of internal nuts may be required to get the yoke mounts free. In that case, the lamp may have to be removed first, anyway. Regardless, if not already done, detach the yoke along with any associated mounting hardware. Remove the clamp or stand adaptor and place them aside. Retain the date tag (if there is one) and place it with the lamp so it can be reattached or recreated upon reassembly.

  4. Electrical:  Remove the plug if possible, and loosen the electrical strain relief. Detach the ground lead from the fixture body, placing small hardware into a conatiner with a locking cap such as a pill bottle, and from there then into one of your parts containers. Most larger PARs allow removal of the socket and wiring by pulling the line cord back through the body, permitting the socket to be taken out with line cord intact.

       For those fixtures with moulded plugs, you will have to decide if you want to detach the electrics or tape them up for the fixture painting phase of this overhaul. It is generally best if the electrics can be completely removed, though. This will mean disconnecting the line cord from the socket usually by removing crimp connectors or wire nuts. Loosen the strain relief and pull the cord out through the body.

       PAR fixtures with mounted sockets will require some disassembly in order to get it out. Removing a rear cover might also be required beforehand -- in some cases having to drill out rivets to do so. It may be so difficult to remove some sockets of this type that they might have to be left in place.

       LED models will have to have their line cords disconnected from their internal circuit boards, along with any data lines going to fixture body XLR connectors.

  5. Final Disassembly:  Now remove the strain relief. Detach the lamphouse access cover (door) if possible. This step may be unnecessary if the fixture is in good shape. Otherwise, for straightening or for certain other maintenance purposes, it's better to not have to deal with an access cover flopping around. If its hinge is welded and the pin cannot be removed, the access door will have to stay with the main fixture body for the rest of the overhaul.

       Remove any remaining brackets, mounts, fittings, and hardware. You should now be left with just the body shell in one or more pieces.
 

(Image Left: Detective with Magnifying Glass) INSPECTION

  1. Body:  Look at the body to see if there are any dents or bent parts. Repair as necessary. To pound out dents, use a wooden form and rubber mallet to lessen metal damage as compared to a direct blow from a metal hammer. To protect finishes that are not to be painted, cover with a thick, soft cloth.

        Inspect the bolt mounts for the yoke; they should not be worn or damaged. If so, then it means a trip to the machine shop to have them re-threaded, unless you own a tap & die set. Note that some models use a "grab plate" locking mechanism, so the yoke mounts are free to pivot, thus stripped threads are less of a problem.

  2. Yoke:  Look at the yoke. Note any burrs that should be filed off, and if straightening will be needed. The latter can be done using a vice to squeeze ripples flat, and as a clamp to permit reshaping by hand.
 

(Image Left: Shop Tools within Oval Borders)
       RECONDITIONING

  1. Initial Restoration:  If the fixture is very dirty, you may wish to clean off the loose dirt with a bench brush, then skip ahead to the "Washing" topic. Return here while it is drying to study the next procedures.

       For severe corrosion on the body or yoke, employ a narrow scraper tool to remove the worst of it, then use a bench-mounted buffer with a brass wire brush to redress these areas. (A brass brush is preferred over steel so as to lessen the chance of gouging.) Because polished or natural aluminum finishes are easily scratched, precisely focus the brush on the bad spots if you plan to retain the aluminum look. Hold or secure electrics that might still be attached in order to keep them away from the rotating brush.

       Should no bench buffer be available, use an electric drill with a lockable trigger, and attach a suitably sized wire brush accessory. Clamp the drill into a vise so that the brush sticks well out into the open. You will find that clamping the drill and moving the parts against the rotating brush works better than clamping the parts. It saves having to clamp and unclamp each part, and having to put the drill down to do this clamping operation every time. Work gloves are recommended, as are hearing protection, and goggles or a face shield.

       Begin to buff the bad areas. Do not press too hard because the wire bristles can score the metal. Use the side of the bristles for finer work with less chance of marring your work. Use the scraper to dislodge flaking paint, then buff the area underneath.

  2. General Body Buffing:  Protect the electrics if they are still attached. Begin to gently buff any painted areas so as to prepare the finish for its repainting. The goal is to remove grime, surface rust, and any patina that has accumulated while the unit was in service.

       For those natural or polished finishes, buff with fine steel wool, or you might try a commercial anti-tarnish product. Some surfaces will also respond to a very fine sanding sponge -- you will have to test to see which method works best without compromising the finish. Set aside prepared items for washing.

  3. Hardware Refurbishing:  Replace any severely rusted parts that cannot be restored. Clean and buff the remaining metal hardware including the pipe clamp or stand adaptor back to being shiny. Take them apart to do this. Use a pair of pliers, preferably a locking type, to hold smaller items. This will give you more control, and it will also distance your skin from the rotating brush.

       Be cautious not to distort these smaller parts by over-tightening the plier locking mechanism. If locking pliers are unavailable, use snub-nose pliers and grip them tightly as you manipulate the item being buffed. Too loose a grip will see parts go flying due to the speed and torque of the rotating brush.

  4. Hardware Protection and Lubrication:  After buffing, protect metal hardware with a thin coating of light machine oil, but use a medium oil for threaded parts.

       Keep oil from soaking into your work bench. A greasy bench is not a good environment for lighting fixtures because oil will work its way into areas where it is not wanted. As such, it is suggested to buy a medium-sized plastic bin such as a dish pan to employ as an oil station. To soak up excess lubricant, cover the bottom with one layer of an old towel. Oil all metal components in the pan, turning them to assure full coverage. Leave parts there until needed for reassembly, being sure to keep the parts clustered into the same divisions as were in the individual containers. If the bin is too small to do this, then only buff and oil each section of parts just before reassembly.

For parts that do not have dust or built-up grime and so
don't need washing, you might now wish to skip to the
"Painting" procedures so that these first items will be
drying while you continue with the steps below.

 

(Image Left: Hand Washing an Object) WASHING

  1. Main Parts:  Place non-oiled items such as the yoke and body into a plastic set tub, or use rubber mats to protect an enamel one. Scrub the unit using hot water and dish soap. Use a tooth brush to get into small areas. Dislodge remaining rust with a soapy scouring pad. For stubborn rust, use a sanding sponge or emery cloth with water. Rinse well. (A cut-off, one-metre length of garden hose is good for this because the end can be squeezed to exert higher water pressure.) Dry with an old towel. Don't use a new one as rusty water will likely stain it. Hang the unit up to air dry its inaccessible areas.

  2. Lamp:  If there is a date tag written on the back, before washing, record the information so it can be restored later. PAR lamps may be washed in the sink with soap and water. If the lamp is very grimy, use a steel soap pad to remove it. Rinse well. Place the lamp in your safe place. If the electrical prongs are tarnished, use the bench buffer to restore them.

  3. Metal Reflectors:  If lens, lamp, and metal reflector are separate, wash the reflector. Plastic soap pads can likely be used on metal reflectors, but test on the back of the reflector to confirm it won't scratch the surface. Keeping the pad well soaped, use a motion that follows the curvature of the metal. If it polishes with no scratches, do the same on the reflecting side. Otherwise, clean with a soft cloth and soap. Rinse and dry.

       For tarnished reflectors, you will have to decide if it's better to have a smooth but tarnished reflector versus a shiny, scratched one. In most cases, the plastic soap pad will produce a better surface, even though there will be some scratching. I vote for the latter if it reflects more light without too much scatter, rather than leaving it tarnished.

       If severely tarnished to the point that it may not be usable, you can attempt to polish it with actual steel wool soap pads, or with automotive rubbing compound. The worst ones will have to be taken to a professional metal refinisher or be replaced.

  4. Glass Components:  Handle non-coated glass lenses and reflectors by their edges. Feel for rough sections that might cause cuts so you'll be cautious around them while cleaning. Blow off loose dust using a can of compressed gas or a large air bulb as used by photographers. With a clean towel in the sink on which to rest glass components for protection, rinse under warm water until no grit is left. You may apply moderate pressure from the hose. Rinse the towel from time to time to keep it grit free. Be careful that your slippery hands don't lose their grip and drop the item. Glass components are expensive, so it is best to only have one at a time in the sink to preclude breakage. Have a thick, clean towel on the counter beside the sink to hold washed items while they air dry.

       To remove film build-up, mix a small squirt of dish detergent and water, and with clean, wet hands gently wash the reflector. Carefully feel for rough edges that might cause cuts so you'll be cautious around them while cleaning. If you feel grit, stop rubbing and rinse; then resume.

       If the grime is particularly stuck, full-strength alcohol can be employed if there is no coating. (See the "coated optics" warning, next.) When finished, rinse and air dry. If you find some streaks are left, you might repeat the process, but use distilled water as a final rinse. Once completed, place glass reflectors into your safe place with soft cloths or paper towels protecting them.

       WARNING! Some glass reflectors and lenses have coatings that increase their efficiency. These can be dulled or destroyed if glass cleaner or undiluted alcohol are used on them. Use only soap and warm water, or 10% alcohol and warm water, for cleaning.

       Even though many glass components can handle glass cleaner and full-strength alcohol, as a caution, use only soap and warm water, or the 10% alcohol solution even if the manufacturer of the fixture states otherwise. It's possible that someone could have replaced a lens or reflector with one which coating cannot handle certain cleaners. If you suspect this, follow the coated-optics cleaning instructions father back.

       Whatever the material, when finished cleaning, rinse and air dry. Place the lenses back into your safe place with cloths or paper towels protecting them.

While components are drying, you may move on to
restoring the electrical parts you removed earlier.


 

(Image Left: U-Ground Plug) ELECTRICAL

  1. Socket Assembly:  Inspect the socket contacts. For side- and end-prong versions, this can often be done by removing the screws and separating the socket halves, unless rivets were used, which will have to be drilled out. If you can get it apart, the contacts will be completely exposed. Burnish off any corrosion there and inside the socket halves. If the contacts remain severely discoloured, you probably should replace the socket. Retain the porcelain halves as replacement stock for future broken ones. Should wires detach from the contacts, they will need to be brazed back on -- soldering often lets go because of the heat generated by these lamps.

       For screw-base versions as would be seen in a PAR 38 fixture, use a very small, wire-brush drill attachment to allow access completely into the socket. Buff the threads and button back to shiny. A rotary mini-tool as used by hobbyists may be required to access sockets that could not be removed.

       Low-voltage PAR 36 and 46 models usually have slip-on connectors or ring terminals at the lamp end of the line cord. If these are tarnished, the latter can be buffed with the electric wire brush. Slip-on terminal contacts are harder to access, but given their low cost, they can be replaced using a crimp tool. Be sure to buy the right connector size and type to fit the lamp's contacts, and use ones with heat-resistant insulators.

  2. Line Cord and Covering:  If the line cord is melted, frayed, or brittle, it will require replacement. Some cords may be covered with a fibreglass sheath. Replace or repair as necessary. If the damage to this is external to the fixture body, you may use electrical tape or heat shrink. If it's internal, cut off the bad part and slide a good section inside. (Tape or heat shrink may not last in there if the temperature becomes too high.) If the amount to be cut off will be excessive, make up the shortfall with an appropriate length of sheathing coupled via heat shrink or electrical tape. If using tape, wind at a 45-degree angle while pulling the tape taut. Reverse direction and wind back over top of the first layer, again at a 45-degree angle.

  3. Connector:  Inspect the connector. Replace if cracked, has heat damage to the plastic or rubber, or has badly discoloured pins that cannot be restored. Otherwise, open the body to see if the wiring is tightly connected and that there are no errant copper strands. When it comes time to reassemble, make sure that the strain relief grips both the cable's insulation and any outer sheathing. Buff the blades back to shiny.

  4. Asbestos:  Should the fixture be an old one with asbestos wiring, it is generally best to replace with a new line cord. Asbestos conducts electricity when wet and is hazardous to breathe if it is shedding. Put the removed wiring into a plastic grocery bag and send to your local Hazardous Waste Facility. Some later fixtures used a better-quality asbestos covering that does not shed; if the fixture will be used indoors in a permanent installation, and if the asbestos has not been compromised, you may reuse it unless local electrical codes forbid it. More electrical work will be covered in the "Reassembly" phase, farther on.
 

(Image Left: Spray Can) PAINTING

    Paint Choices:  If there are parts that are rusted or discoloured (other than electrical or the reflector), painting will be required. The usual colour would be flat black. This is recommended for all interior body surfaces in order to minimize unwanted reflections. The paint chosen should be able to handle directly radiated heat. Barbeque paint is a good choice. Buy a test can first! Some barbeque paints have a flat black cap, but actually dry with some degree of shine.

    For the exterior, you may want a different colour. This might be to dress up the light, to better identify your lights from those belonging to others, or to give your show a uniqueness if you like to have visible fixtures. Even so, endeavour to stay with a darker colour to minimize external reflections. A satin (semi-gloss) finish is recommended regardless of the colour chosen.

Now gather your paint materials as given
in the preliminary list near the start
of this article and do the following:

  1. Preparation:  Fixtures with a polished or natural finish that are to be painted must have their surfaces roughed. Use a coarse sanding sponge to dull all the areas that have never been painted. If not already done, scour all painted areas with the bench buffer. You need not take off all the old paint -- only that which is loose, and of course, surface rust should be removed as previously discussed. Dust off the parts with a bench brush. You may need to also wash them again.

  2. Segregate Areas:  Being sure items are dry, begin by placing masking tape over any areas to be protected from paint such as electrical stickers, or screw threads. To facilitate tape removal, leave a tab on the tape by folding a small bit of the sticky side back on to itself. If the socket and line cord have not been removed, tape these, too. For screw-base sockets that are still mounted, insert rayon batting to protect the threads. Place tape over any other items that you do not want to receive paint.

  3. Painting Procedure:  Put the items onto newspaper in your booth or ventilated area, as discussed in the Work Area Setup. Follow the instructions on the can regarding optimal temperature and for re-coating. Shake the can well and begin to make a base coat in even strokes. Stop the spray at the end of each pass and then restart as the stroke returns. Blend each line of paint with the previous in a manner that does not leave gaps of excessively thin coats or ones that are too thick. Keep the overall coating thin. Allow it to dry, then do a second coat, and a third one if necessary. Since fresh paint can still be soft underneath, leave items to dry over night so that the paint will cure. Repeat the process for the yoke and other parts requiring paint.

       After the base coats have dried, if the exterior is to be a different colour, coat it using the technique above. Keep overspray out of the interior. Partly to keep that different-colour paint outside, but also to limit stray light reflections, it is suggested that the front of the accessory holder and its inside runners be left flat black. This is easily accomplished by leaving the fixture in a nose-down position for all of the exterior paint work. Of course, if the holder has been removed, it makes it much easier to paint it whatever colour you want without employing masking techniques.

       If the nose-down fixture position is not to your liking, a hand-held cardboard mask may be used to keep spray from where you don't want it. Even so, you might still have to touch up the inside after the exterior has been completed. Allow the final coat to dry over night to achieve a harder, more robust surface.

  4. After Each Painting Session:  When completed painting for the day, blow out the paint can nozzle by turning it upside down and spraying until only propellant comes out. To lessen waste, I always do this onto one of the lights just as I am in the process of finishing a coat. When the can is empty, keep the nozzle in case future ones get clogged, and send the can itself to Hazardous Waste.
 

(Image Left: Screwdriver)   REASSEMBLY

  1. Cautious Handling:  There should now be a number of sections and parts that are clean, non-damaged and possibly repainted. Being careful of your new paint work, start to reassemble the fixture in reverse order of the disassembly, beginning with any internal sections. Regarding paint which is dry, but fresh, it may take a day or so for it to harden completely, hence the caution when handling.

  2. Body Assembly:  Restore the lamp access cap along with the hinge and its closure catch or fitting, if any of these had been removed. The same goes for the accessory holder and/or its retainer. Check to be sure that the rear cap aligns with the body when it closes, and that it aligns with its closure strike. It may need to be gently warped one way or the other to accomplish this.

  3. Restoring the Electrics:  Do any remaining line cord work not done before. This might include buffing and oiling the plug blades, taping the cord and/or sheathing, and replacing terminals.

  4. Reinstalling the Electrics:  For LED or separate-component models, mount the circuit board and required brackets. For all models, install the strain relief and route the line cord through the body. Then for detachable plugs, connect the hot and neutral leads of the line cord to the circuit board, or to the socket and using an insulating wafer, if required. Thread the line cord out through the strain relief and attach the ground lead to the ground terminal. If fibreglass sheathing is to be used, slide it on to the line cord and position it. Reinstall the socket assembly and pull excess line cord out through the body, leaving a bit of slack. Connect the line cord leads to the plug and slip the outer sheathing into the plug's strain relief. Tighten all.

       For line cords with plugs attached, slip heat shrink onto the cord followed by the outer sheathing, after which secure the sheathing at the plug body by taking the heat gun to the shrink. Draw the line cord through the strain relief and into the body. Trim sheathing to remove slack.

       Attach the hot and neutral leads to the socket, or attach to its leads with wire nuts or crimp connectors. Be sure to observe electrical polarity when rewiring: In Canada, the hot (black) lead goes from the center contact of the socket, down the line cord and onward to the brass screw of the plug. The neutral (white) lead is connected to the silver screws, the ground lead to the ground post on the body of the fixture and to the connector's green screw. Symmetrical PAR sockets, such as the Mogul End Prong and Medium Side Prong ones, do not observe polarity. The hot and neutral leads may go to either side, but should still go to the correct terminals in the connector. Silicone the socket's contacts if this has not already been done.

       Remove any slack in the sheathing and tighten the body strain relief. When the light is fully assembled, the sheathing should run from the socket assembly (allowing for the splay of individual leads), along the line cord and into the plug's strain relief at the other end. If the plug is the moulded type, the sheathing should go up to it and be secured with tape or heat shrink.

  5. Brackets and Hardware:  Replace any remaining brackets or fittings, and lubricate/protect any hardware that had been not done before this point. Keep oil from affecting non-hardware surfaces. For separate-component models, mount the reflector and socket, and then, if used, the lens-turning mechanism. Use silicone in the socket and on the lens turner.
 

(Image Left: Multimeter)   ELECTRICAL TESTING

  1. Continuity Test:  Use the `ohms' setting of your multimeter to confirm a continuous electrical path from plug to socket. Check the neutral and ground paths, as well. `Zero' ohms should be the reading. Diagnose and fix any problems.

  2. Shorts Test:  Test for shorts between hot and neutral, and from each conductor to the metal fixture housing. If the meter reads anything but "infinity", there are problems. Diagnose and fix before moving on.

  3. Lamp Test:  You may elect at this point to install the lamp as an additional test, but can wait if more parts have yet to be placed. Do a lamp continuity test before putting it in. If all is well, move on to the alignment.
 

(Image Left: Chart with Arrows)
     ALIGNMENT

Install any remaining parts, but you may choose
to leave the yoke and pipe clamp until after
the next procedure has concluded. Install
the lamp, if you have not already done so.


  1. Alignment?  No adjustment is required for PAR fixtures because the lamp/reflector/lens is a pre-aligned unit. Regardless, the lamp and/or its retainer could be out of place, as could the components of models using separate lamp, reflector and lens. Therefore:

  2. Lamp:  Test the lamp with your ohm meter, and if not already done clean the bulb. If the reflector, lens and lamp are separate components, use methanol alcohol to remove finger oils from the bulb. PAR lamps may be cleaned with soap and water or glass cleaner, as discussed earlier. (Silicone may be necessary for the PAR bulb. See the "Final Procedures" section farther on.)

  3. Support the Fixture:  Begin by setting the light in the alignment cradle so that it is level, and the center of the fixture opening aligns to the screen's center point. Plug the fixture into a dimmer and reduce light output to the lowest setting that still produces a bright oval or circle. Lowering the voltage is done to lessen the chance of lamp burnout during possible rough movement as its alignment is adjusted

       The area of light should be directly opposite the front of the fixture. If it is not, look to see that the lamp is seated properly and that its retainer clip or ring is in the correct position. Adjust as necessary.

       For PAR 36 and 38 models, ensure that the socket and/or lamp is seated properly to allow the light to exit the fixture in a straight line without shining directly onto the fixture's interior on the way out.

       For separate components, check to see that the reflector is seated and retained properly, and that the socket and lamp are aligned within the reflector. Look to see that the lens is not canted to one side. Adjust as necessary.
 

(Image Left: Roll of Tape and a Marker) FINAL PROCEDURES

  1. PAR 46, 56, 64 Lamp:  Because the larger PAR lamps project an oval beam pattern, they must be able to rotate to position the pattern onto what is being lighted. Confirm that the lamp can rotate freely. If not, use a paper towel to apply silicone to the edge of the bulb where it contacts the fixture so as to allow smooth turning. If the lamp binds, you may have to bend the metal "shelf" on which the lamp rests, or may have to gently squeeze the fixture to bring it back to round.

  2. Separate Components:  For those models that have a rotating lens or lens holder, make sure it can turn freely. Silicone the lens edge or rotation mechanism for smooth operation.

  3. Date Tagging:  This is an important step because the tag will give an indication of lamp service life. If the time period is less than expected, there may be a problem with the fixture, its location, or its input voltage.

       Date tag the lamp by writing on the back with a permanent marker. Write near the edge of the reflector where heat is lowest. Allow for the retainer ring or mechanism to not block the tag. Do this twice, 180-degrees opposite one another. This is so that the date tag can be read easily regardless of the lamp's rotation.

       For separate-component models, write the date on white electrical tape and stick it to the inside of the yoke on one of its vertical surfaces -- usually the one opposite the tilt-lock knob. Be consistent so that you and your crew will know exactly where to look. Don't use the underside of the top of the yoke because heat here will be greater than along the sides when the fixture is hung in its typical orientation. Make the tape long enough to have space for two dates. This way, it only needs to be renewed every second lamp replacement.

You now have a refurbished PAR fixture
of which to be proud. ENJOY!

(Now do the rest of them...)



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