No announcement yet.

'52 Commander clock black light not working - bulbs work

  • Filter
  • Time
  • Show
Clear All
new posts

  • #16
    Thanks for mentioning the side windows.
    I suppose I can see one of the rivets that you referred to in the fourth image here:
    (I'm not planning on drilling the rivets.)
    It just occurred to me that perhaps I could blow air up there to clear dirt away.
    And that I could try to do some more cleaning, not just on the inside of the filters but on the outside as well.
    I'll give that a try (another day).


    • #17
      I have a 50 Commander with very low miles and the instruments and speedo glow very nicely as they have never been sunburnt. The clock has the same symptoms as yours and a very careful cleaning made no difference. At night it is only just visible. Chalk it up to a design flaw.


      • #18
        52 Commander Thank ya for the update!

        I'm still learning here too... Had no idea about the solarization issue with Wood's glass, but have noted it in old sidewalk light prisms. Oddly enough, that's a reaction to the manganese dioxide that was added to glass to initially make it clearer. I doubt this would be an issue in your gauges with the relatively minor amount of ultraviolet that an incandescent produces; probably more so with gas discharge lamps like fluorescent and mercury vapor, as much of their output is shortwave UV. Also sounds like chemical reactivity of some components of Wood's glass to moisture and carbon dioxide might have a little effect on its stability. I am still betting that the phosphorescent paint is the weakest link
        Whirling dervish of misinformation.


        • #19
          I guarantee the weak link is the lack of ultra-violet light reaching the phosphorescent face. Every time someone tells the forum that they shine a UV light on the gauges, and they glow like never "clicks" with the rest of the commenters that hey, maybe we need more UV .
          Bez Auto Alchemy

          "Don't believe every internet quote" Abe Lincoln


          • #20
            Not trying to get in a urinating distance match with you, but I'm still wondering how these gauges managed to glow adequately with the weenie incandescent bulbs when they were new. No one shuffled the location of the lights or the light source over the last 70 years, so what's left?
            Whirling dervish of misinformation.


            • #21
              No peeing is needed! . What I'm not so succinctly trying to convey, is yes, the "glow" is now degraded over the years as the paint looses it's phosphorescence capabilities. But that it can be further enhanced to work better than new with upgraded UV. Yes, they are weaker now because of the filters degrade AND the paint oxidizes and looses it's ability to absorb energizing photons. Short of taking the gauges apart, and cleaning the faces (which I do) the average person CAN achieve good results with improved ultra violet lighting.
              What is left is go out and but some UV lights. Why not try it instead of arguing the point? There is NO way to have them work as new after 70+ years unless you find NOS that has been stored in a dark cave away from pollution, ozone, and sunlight.
              Take into account that, yes, that they are now 70 years old. Also, that the glass has darkened, and collected dirt. That the zinc phosphate paint has oxidized. That the "windows" on the side of the instrument has oxidized, and are not as transparent. And finally, that our eyes are not as good as they used to be! .

              Last edited by bezhawk; 05-07-2021, 05:08 AM.
              Bez Auto Alchemy

              "Don't believe every internet quote" Abe Lincoln


              • #22
                Ross thank you for your observation - I'll set my expectations low! (but still above zero) :-)

                Given that the clock paint glows brighter than the speedometer paint (using an external black light) I expect that something in the clock will light up if I can get the "light path" clear. Even dim lighting will be much better than what I have now.

                Lark Hunter You're welcome!

                ( bezhawk Brad - I'm nodding to your comment that our eyes aren't as good as the used to be...)

                I ordered a wireless endoscope today to (hopefully) enable me to see better what is up under the dash (while saving my back and neck some contorting too).

                (if it works well) I'll learn what is up with those "windows" and perhaps I can use it to better direct some WD40, and some air pressure at all related surfaces (in and out of the glass, and on the window) to clean up the light path.

                I looked for UV bulbs that would fit the ba9s socket here, didn't see any:
                Brad, have you found UV bulbs that fit the stock socket?
                Ah, how about this:

                Last edited by 52 Commander; 05-07-2021, 11:46 AM.


                • #23
                  Originally posted by 52 Commander View Post
                  This is the first that I noticed that the PNDLR indicator lights up (dimly) too.
                  If that Lens is not really dirty, THAT is making me wonder if some of your problem is Low Voltage, poor connections, weak grounds etc.
                  Does the Battery Voltage read over 6.0 and over 7.0 running?

                  Usually these small #51 and Larger #53, 6 Volt bayonet based Bulbs are reasonably Bright.
                  Second Generation Stude Driver,
                  Proud '54 Starliner Owner


                  • #24
                    52commander If you get UV bulbs from them, please report back on how well they work, good or bad.

                    The picture of the bulb that looks most intriguing is the side-projecting surface mount that they picture. Unfortunately they don't show that as a choice. I learned from soldering up my own UV LED bulbs, that we need the UV light going sideways. An LED's narrow beam doesn't seem to bounce around much within our instrument cluster.


                    • #25
                      Champ51 I just took a look at that site and the photos. I see what you mean.
                      To buy the side-projecting SMD (surface mount diode) version first pick the Bulb - Base = 44 Bayonet (BA9S). Then pick the Bulb Style = 5 SMD Tower.

                      StudeRich Excellent point. To support what you wrote:
                      a) IIRC the voltage at the trunk light was 4.72 volts (when I measured it months ago - the engine was not running).
                      hmm. although when debugging the convertible top not working there was a full 6V at the motor
                      b) when out driving two days ago in bright daylight the guy behind me told me that both brake lights were not working. At night in the garage, with the brake lights less than a foot from the garage door, I stepped on the brake pedal and only a very faint bit of red light illuminated the white glossy garage door.

                      I'll be out in the garage with a voltmeter at some point. This is my Uncle's car. He lent me it to have fun with. (Great guy!) I decided to try to fix some minor things (that I thought would be easy to fix!). (replacing the map light was quite challenging!)

                      If you have tips on finding the problem I'm all ears. I just plan to measure the voltage at different points, starting with the battery itself. And maybe take the battery cables off and wire brush 'em a bit. All of this is new to me - and I'm having a lot of fun with it! I didn't even know that it was a 6V system until a friend (who was a mechanic) told me about that. I did learn that the system has a positive ground reading this forum.

                      Last edited by 52 Commander; 05-08-2021, 06:47 AM.


                      • #26
                        There is a procedure for adjusting the voltage regulator. If it is not covered in the shop manual, I have seen it in older Motors manuals. I believe you want 7.4 volts running .
                        Bez Auto Alchemy

                        "Don't believe every internet quote" Abe Lincoln


                        • #27
                          Gents, sorry for my long delay. (I thought my back was up to some more contortions, but I already feel that I'll be paying for this. Anyway ... )

                          StudeRich ...
                          I measured 5.86 / 5.87 volts at the lead that comes out of the light switch that goes up to at least one of the light bulbs in the clock.
                          (There are two wires in the particular light switch connection - I followed one wire to the lower clock bulb.)
                          This is with the car not running.
                          So, it's not over 6 volts, but it's close to 6 volts.
                          Right at the battery the voltage is 6.27 volts.

                          For some reason I was sticking my hands up behind the clock to see what I'd feel. I felt something hot. It was the upper purple filter (Wood's glass).
                          I could see the bottom purple filter lit up, glowing purple! I got a cue tip (moistened with saliva) up there and rubbed that supposed window.
                          Some (not a ton of) dirt came off. I'll try again at night to see if any light comes through to the clock interior.

                          bezhawk Should that whole "window" be transparent? It does appear to be brown and opaque.
                          (it's similar to image 4 of 5 here: )
                          Do you have suggestions on how to clean it - while it's still attached to the clock, up in the dash?

                          I haven't tried the wireless endoscope yet.



                          • #28
                            I just had to check tonight ... I turned the lights off in the garage and went out with a flashlight to see my way.
                            I turned the instrument lights on. After my eyes had some time to adjust to the darkness I could see a tiny bit of illumination of the clock's hands and digits.
                            This inspires me to try more ways to clean the purple filters and the "windows".

                            Open to suggestions. Note that these are quite hard to reach.



                            • #29
                              I think you *might* be able to achieve slightly better results doing a little more cleaning in situ, but exactly how much I dunno... Truth is, as much as I sorta know about this setup, at the end of the day I'm still speculating. I still have never encountered a fully restored instrument cluster in one of these cars, and am going to try to nose around to see if there's enough interest between us and the '49-50 FoMoCo guys and gals to warrant spending the energy finding a solution. Can't say exactly when this will happen; but I do want to find at least a speedometer, and a clock that's equipped with the indirect lighting-through-windows like the one shown in this topic to experiment on first (pretty much the exact gauges I passed by for very reasonable prices at a couple of swap meets since I didn't have a use for them at the time)... I have a number of products I'd like to test out for functionality and durability.

                              Yes. Both of those windows should be transparent to mildly translucent. Your voltage of ~5.86-87v with engine off near the instrument panels sounds good--- 4.72v @ trunk light... not so much.
                              Whirling dervish of misinformation.


                              • #30
                                Lark Hunter thank you for your continued interest and enthusiasm around this.
                                A great friend recommended using WD-40 as a cleaner (for other purposes). I will use that - inside and out.
                                (but not soon - need to wait for back healing first)
                                If the results are still abysmal I will follow bezhawk 's advice and buy those UV LEDs.
                                My concern is that if that "window" is (nearly) opaque then the results would still be marginal.
                                Of course, I can only get to / clean one side of each window.
                                If the opacity is through and through (and not just dirt on the surface) (@bezhawk mentioned that they oxidize) or if the other side of the window is dirty, . . . well, it doesn't seem like this'll work out.