Atlantic Illumination Entertainment Lighting

(Image: Photographic Clamp Light)

AIEL Shop Tips

WORKLIGHT
MAINTENANCE

Here is a complete procedure describing
how to maintain the clamp lights described
in the Kits section of this website.


It may appear that worklight maintenance is intuitive or even
unnecessary. Yet, they are regularly used and often
abused, then frequently neglected until they must
be replaced. Despite their low price, anything
that keeps costs in check is a good thing.



INFORMATION HERE 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

Inspection

Disassembly

Repair

Reassembly

Final Testing

Adjustment


 

  Preliminary

Worklights are very basic and often taken for granted or
ignored compared to stage lights when it comes to maintenance
or overhaul. However, they are an important fixture for any backstage
worker or tech and should be maintained. Now yes, these fixtures are
cheap to replace, but appropriate ones can't always be easily located.
Besides, a Frugal Tech endeavours to make repairs, not buy replacements.


    You should make the following available:
  • Selection of Replacement Parts
  • Screw Drivers
  • Pliers
  • Multimeter
  • Crimp Tool and Connectors
  • Soldering Iron or Gun
  • Solder
  • Emery Cloth
  • Steel Wool
  • Electric Drill or Buffer
  • Brass Wire-Brush Attachments
    (Small and Large Diameter)
  • Tooth Brush
  • Electrical Tape
  • Heat Shrink
  • Heat Gun
  • Flat Black Spray Paint
  • Rayon or Cotton Batting
  • Light, Spray Oil
  • Silicone Spray
  • Methanol or Rubbing Alcohol
  • Lacquer Thinner
  • Rags
 

* INSPECTION

    Take a close look at your worklights; revealed may be distorted,
bent, or broken reflectors, and/or cracked sockets, missing or broken
clamp hardware, non-functioning switches, and/or stiffness of operation.
Choose the lights to be repaired or overhauled and move to the next section.


 

*   DISASSEMBLY

  1. Lamp:  Remove and store in a safe place. If it is broken, pliers may be required to grip the edge of the lamp's base if that is all that remains. Be sure to clean out any remnants from the socket and reflector.

  2. Reflector:  Unmounting the reflector usually requires that it be turned and pulled, but there may be a bracket that must be loosened so it can be taken off. Alternatively, some might have set- or mounting-screws that will have to be removed.

       Realise that reflectors on some models of these lights will not be able to be removed. This will be addressed farther on.

  3. Socket:  This is commonly attached to the spring clamp with a two-piece, semi-circular bracket. This bracket grips a ball fitting by using a bolt and wingnut to adjust tension. Remove all these, but leave the ball fitting attached to the spring clamp, unless it's broken and must be replaced.

 

*    REPAIR

  1. Socket:  Look at the internal threads and center contact (the button) of the socket. Buff off tarnish with a small wire brush attachment in an electric drill, being cautious not to catch the button's edge which might bend it. Lubricate the contacts with silicone.

       If the center contact is one of the "hinged" tab types, you may need to raise it slightly with a screw driver or hook tool after buffing. This will make for a better connection between it and the lamp base. Do not bend too far; it is possible to snap it off.

       Replace the socket if the metal contacts are damaged or so tarnished they cannot be brought back to a shiny finish. Replacement will also be required if the outer housing is split or chipped and shows exposed metal.

       Be sure to observe electrical polarity when rewiring: In Canada, the hot (black) lead goes from the center contact of the socket, through the switch, and onward to the brass screw of the plug. This is internally connected to the polarised plug's short-height prong.

  2. Switch:  Work the switch. If it's stiff, put light spray oil or a lubricated contact cleaner into it, and work it some more. This will usually result in smoother operation. Wipe off any excess product. If it remains difficult to operate and/or if electrical contact is intermittent, replace the switch. This is not always easily performed due to design -- you may have to replace the entire socket/switch unit.

       If replacement is not feasible or economical, consider bypassing the switch by bridging its wiring points with a short, soldered wire so that the light will always come on as soon as it's plugged in. This will be fine for one-nighter shows where the light will be unplugged after each gig. If using the lower wattage of recommended lamps as discussed in Worklight Kit, their service life is so long, power consumption so low, and the heat generated is so minimal, that they could be left on even for a few days. At 20 cents a kilowatt hour, the cost would be 5 cents per light per day.

       However, energy is a product not to be wasted in the 21st century. Using the 20-cent figure just given, one should realise that a dozen of these lights burning for a total of 50 days a year would cost $120. That money would buy boxes of replacement lamps for these fixtures. So unplugging these lights after each show is the better option. If this task sounds tedious to you, reserve these always-on lights for one-nighter gigs. Mark each bypassed version so they can be discerned from the switched ones.

  3. Electrical Cord:  Inspect the line cord, especially where it enters the socket and the plug. Because of stress at these points, this is where insulation becomes compromised. Repair any abrasions, frays or splits with electrical tape or preferably, heat shrink. Should you replace the cord use #18, flexible lamp cord in black colour. Think too, about extending its length from the manufacturers' typical 1.5 or so metres to 2 or 2.5 metres to better reach those out-of-the-way outlets backstage.

  4. Electrical Connector:  Buff the prongs of the plug with a wire brush. Coat with a light oil. If the plug is damaged or has loose prongs, put on a new one. When replacing, use a polarised plug and observe proper wiring polarity. (As stated earlier, the hot side of the circuit should run from the socket's center contact through the switch to the connector's brass screw.)

       If you find that the prongs slip too easily out of outlets, take two pairs of pliers, one needle nose, the other snub nose. Grab one prong at a right angle near the plug body with the needle nose pliers, and then use the snub-nosed pliers to grab the rest of the prong straight on about one third of the way from its end. Gently and slightly twist. Repeat with the other prong, being sure to twist in the same direction.

       Never do this operation with just one pair of pliers; that would stress the point where the prong enters the plug body and cause looseness. For the same reason, never splay the prongs apart from one another.

  5. Continuity Test:  Use the `ohms' setting of your multimeter to confirm a continuous electrical path from plug to socket while the switch is in the `on' position. `Zero' ohms should be the reading unless the switch is set to `off', whereby it will read "infinity". Check the neutral path, as well. Unless a double-pole switch has been used (unlikely), the reading will always be `Zero' regardless of switch setting. Diagnose and fix any problems.

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

  7. Reflector:  Reshape the reflector if required, and pound out any dents. A ballpeen hammer is good for the latter. Tap gently; these reflectors are usually made from fairly thin aluminum. Should the reflector have a bayonet (push & turn) mount, pay close attention to it. If its edges are not flat and regular, the reflector will be loose and easily dislodged. Re-form these with the hammer and snub-nose pliers as required.

       Clean the reflector using a toothbrush to get into small grooves. Spray both inside and out with flat black paint. Follow the instructions on the can regarding optimal temperature and for re-coating. The reason for painting the inside of the reflector is to better contain the light so backstage spill will be at a minimum.

       Consider using an aluminum primer if this is the first time the reflector has been painted. Use several thin coats, not just one thick one. Rushing to finish the paint job by applying only one thick coat will see it more easily scratched or worn off. Set aside to dry between coats.

       An alternative might be to do the outside with semigloss paint for a more professional look. However, when it gets scratched it seems to appear worse than a scratched flat-black finish.

       If the reflector has been unable to be removed, complete the remaining steps in this section except for lubrication and oil protection. When returning to paint the captive reflector, insert rayon batting into the socket to completely cover the button and threads. Mask other parts such as the socket and spring clamp, then paint as above.

  8. Bracket and Hardware:  Restore the curves to the semi-circular bracket halves if they have become bent. Remove any tarnish with a sanding sponge, emery cloth or steel wool. Replace damaged, broken or missing hardware, and buff the bolt, wingnut and any remaining hardware to a shiny finish. Wipe all metal with an oily rag to provide a thin coating of protection.

  9. Spring Clamp:  Buff the clamp to be shiny, and if the clamp has a coil spring located near the gripping end, clean and lubricate it. Tighten any hardware. If there are rivets, tighten them by placing one end on a hard surface such as an anvil and tapping the opposite end. A pin punch with a broad tip may be required to access those ends that are partially obscured. Tap until the rivet is tight enough to prevent movement, unless it is a pivot point. In the latter's case, snug the rivet enough to improve tolerances, but not so tight that movement is impeded.

  10. Grippers:  Repair the grip surfaces. These might be pads, or rubber/vinyl tubing. In some cases, one may be able to get away with rejuvenating them if they are not split. Use lacquer thinner on a lint-free rag to wipe the pads or tubing until dirt is removed and a new surface has been exposed. Do this in a ventilated area, and protect skin and eyes from the thinner.

       Severely damaged tubing-style grippers will need to be replaced. If none is available, consider using thick heat shrink as a replacement. It can be slipped over the remaining grippers to hold them in place and provide extra padding, or can be used by itself. Having proper grip surfaces makes for a better-working fixture -- a non-slip light stays focused.

  11. Gooseneck:  If your worklight has a gooseneck, lubricate it with a bit of light spray oil. Wipe off the excess. Flex the neck; listen for squeaks and check for stiffness of operation. Lubricate the offending section and recheck. Remove excess oil.

  12. Lamp:  Buff the base of the lamp with steel wool or a brass wire brush to remove tarnish or corrosion. Apply silicone to the threads and button. Clean the bulb using alcohol.

       It is suggested that the lamp employed be an 11- or 40-watt, non-coloured incandescent. Compact Fluorescents are too fragile and extend beyond the reflector. LEDs may be used if they are not too bright, can be contained wholly within the reflector, and have a 3000-degree, or lower, colour temperature. For more thoughts on this, see Backstage Blues.

 

*   REASSEMBLY

    If a captive reflector has not yet been painted, do so now following
the procedure in the Repair section. Set it aside over night so that the
paint will be both dry and cured. Then, start the reassembly process
below being careful to preserve your new paint work.

  1. Clamp and Bracket:  Loosely reassemble the spring clamp and its socket bracket. Note that there may be a square opening on one side of the latter into where the underside of the bolt head fits. Ensure the bolt comes through from that side. Consider adding split and flat washers against the wing nut. They will make for an easier and more secure head adjustment.

       Be consistent as to which side gets the wingnut so that all fixtures will be the same. Because it's a right-handed world, it is suggested that the wingnut be on the right as viewing the light from the front. The reason is that most backstage lights will be mounted and adjusted from this position.

  2. Socket:  Into the loose halves of the semi-circular bracket slip the socket and tighten the wingnut enough to hold it in place. A final positioning will come later.

  3. Reflector:  After the last coat of paint has dried and cured, restore the reflector to the socket if it had been removed earlier.

 

*   FINAL TESTING

  1. Electrical:  Replace the lamp. Test that it works by plugging into an outlet and that the plug seats firmly with no play. If there are issues, go back through the steps to determine what to do to complete the work.

  2. Hardware:  Inspect the light to be sure all hardware has been reinstalled, and that it is in the correct location and orientation.

 

* ADJUSTMENT

  1. Ball Fitting:  Position the ball's location by using a screw driver to widen the coil loop ahead of where you want to push the fitting. If the light is to be clamped to a wall, the best position is likely to be center, which is how these lights already come from the factory. If it is to be clamped to a table's edge, position the fitting toward one side of the coil down near its bottom. This allows the reflector to be angled down more on to the table.

  2. Tensioning:  Finally, adjust the firmness of the socket bracket on its ball fitting with the wing nut. It should be loose enough for one to be able to set the angle of the light as required, but tight enough to maintain that position during usage.

You now have a reliable, functioning worklight at
the ready to assist techs and your clients backstage.



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