Exterior Light Refinish

Our exterior lights were looking pretty shabby. The original antique / brushed brass was tarnished and dull. 26 years of UV damage had destroyed the original clear coat. There were house paint splatters on them as well.

This is one of the smaller lights, by my shop patio.

image of light before
refurbished light

This was also the first major powder coating project after the test pieces. I figured that getting a home improvement project done before tackling the workshop powder coating projects would help win some brownie points and help justify the equipment investment.

The lights are made of thin brass stock. The knurled balls on the corners and for the removable top (for light bulb change) were about 50% frozen on due to rust. They are screwed onto about 1.5″ pieces of threaded rod which were crimped into the corners of the lights. So in the cases where they were stuck the threaded rod came out as well. This allowed fo disassembly of the class panels and removing of the top. From then on it was a matter of starting at the finials and working my way in. Each rounded section had its own nuts and / or coupling.

Some parts, notably the threaded rod pieces needed an electrolysis treatment to remove the rust or corrosion. The parts were then bead blasted to remove all of the old finish and corrosion. Bead blasting for each lamp took about an hour. The small parts were mounted to a piece of masonite so they could be held while blasting. A wire was zig-zagged on the back side to connect all of the parts for grounding while powder coating.

small hardware on board after powder coating
Back side of the small hardware board showing the grounding wire and retaining screws or nuts

This board was simply placed on the bottom of the oven for baking or on the lowest rack. The other parts were hung via stainless wire from oven racks for powder coating and backing. Please remember to wear a dust mask / respirator while powder coating and blasting. The dust is a really nasty lung irritant. I neglected this at first (like you see in many of the youtube videos), and my lungs hurt for 3 days. Now I use my Miller Eclipse P100 respirator religiously when doing the blasting and powder coating.

The many other flat and domed pieces were hung prior to coating and there are a few important tips:

  • Only load 1 or 2 parts at a time prior to spraying the powder. Having a rack full of parts limits your ability to maneuver the gun and get even coverage. Load 1 or 2, spray, load a couple more, etc. Besides the overspray will help finish build on the previous parts.
  • Add a ground clip to each part rather than relying on the hanging wire and rack for grounding. With the lamp parts the center hole is an ideal point to add a clip lead ground. It wont show later, it is easy to coat after clip removal and you can get some leverage from the insides of the domes when removing the clip. I bought a new batch of alligator clip leads for just this purpose.
  • Hang the bigger parts with 2 wires. They WILL swing as you load them into the oven and this will lead to bare spots where the powder is knocked off.
  • Don’t be greedy and overload the rack with lots of parts. They will swing and bang together leading to bare spots and other defects. 4-6 at a time seems to be the limit. 8-10 is just asking for trouble. The bake time on these thin parts with the powder I was using – Eastwood Architectural Bronze is only 23-35 min (20 min after the part hits 400F). So you can still do over 2 batches per hour and have a nice break in between.
  • It is better to transfer full racks of parts in and out of the oven rather than singles and trying to hook them on and off individually (or maybe I am just a superb klutz with limited motor skills).
  • If possible hang the parts with >3″ and preferably 4+” gap from the rack (another variant of “don’t get greedy”). You need the space and don’t want to be spraying downwards through the rack if at all possible.
  • The corollary to this is don’t push your air compressor too hard with long bead blasting sessions. My DeVilbiss “6 HP” 60 gal unit gets really hot after 30 min of continuous run time (which happens while bead blasting even at 50 PSI reduced pressure to not cause the beads to disintegrate). At that point, the air is hot going into and out of the tank. Then the moisture (and oil) make it past the moisture separators and start showing up as discoloration on the parts while blasting. That is the signal to stop and let things cool down. The blast cabinet requires 9-12 CFM @ 50PSI for glass beads continuously while blasting (far more than a spray gun). I don’t have a chiller / condenser for the air lines (another $700+ investment) which would eliminate the condensation issue but not the overheating compressor .
Oven before I switched to a special rack for the panel dividers which are laying on the non-stick foil

Lamp parts hanging after initial fusion of the powder coat
First 2 domes attached Note the spacer bracket between the pipe sections
Base attached to wall bracket
Cushioned pliers to attach nut and threaded rod. Blue tape or electrical tape work well to avoid scratching the parts.
Glass in, ready for the top

I used a variety of textured clear “stained glass” to replaced the old beveled glass panels. I like the look of the textured glass better than the clear. Plus I did damage a few of the beveled glass pieces slightly during disassembly. The glass cuts are simple straight line snaps. However the seedy glass often deviates a bit from straight if the cut is near the bubbles. So a glass grinder or coarse grit diamond stone is a big help. I had not done any stained glass work for a few years. The internet supplier I had used previously used, was out of business and Milwaukee Art Glass is currently only open by appointment (as I found out on arrival). Some of the glass came from Hobby Lobby (which I detest, but is the only other local alternative I could find). Aside from the philosophical and general quality aversions, the small sheets they sell, would only yield 3 panels (and I need 6) per light (and there were 5 lights) with a lot of waste. However, some may be usable as I do the upcoming path light project.

“Large” light completed

Overall, this was a very satisfying project while building a variety of new skills. Replacing these lights with new ones would have cost much more than the powder coating equipment investment. There were 5 lights in all. Next up will be new scratch built path lights for the front sidewalk.

Aside from new tools, material cost for the 5 lights was:

  • Glass bead blast media ~$20 for about 10 lbs consumed
  • 1 lb of Architectural bronze powder coat powder $12.95
  • Glass ~$50 – mixed sources
  • New LED lamps from Menards (FEIT 100w equivalent) $25