I have been noticing this lately as I re-ballast my track in spots.
The original ballast Woodland Scenics, around 10 years old, is discolored.
Instead of the original gray/light gray blend, it now has a brownish cast to it.
Is the fluorescent light causing this?
Is it the matte medium?
What is the cause?
Rich
Most likely the matte medium. I´ve had that with the glue I used, which became discolored after a few years, turning into a yellowish something.
Most likely the fluorescents. Also of note is the color of WS is different sometimes in different batches.
This may be interesting to note, but shouldn’t be a problem on the layout. Prototype roads may have different colored ballast when it comes from differnet locations. Repairs may look quite different from the “normal” balast on the mainline. I have even planned to have some repaired spots, which will use differenet colors.
I have heard that some flourescent lighting can cause fading.
Have fun,
Richard
Hmm, matte medium, fluorescent lights, different dye lots.
All of the above?
Rich
I wouldn’t mind the difference being attributable to repaired locations, but what bothers me is the dull appearance of this discolored ballast.
Rich
[2c] For what it’s worth…I would be inclined to believe it’s the matte medium, rather than the lights.
Got a lot of stuff, in my garage which has a bunch of fluorescent lights since the 80’s and nothing is discolored…if that mean’s anything.
Take Care! [:D]
Frank
Frank, that is my inclination as well. I am anxious to hear what others think about this discoloration.
Rich
When my club reballasted some of our older modules for the NTS in 2014, we noticed that the new light gray ballast was slightly lighter than the old ballast (we had a sample from the previously used ballast still in container).
Not sure if when people refer to the tubes whether you’re talking the color temp/CRI or a more likely culprit, UV. Some tubes give off considerable UV. You can buy tubes that slip over the glass to filter it. Museums use them even with low UV tubes, because they think really long term.
That said, the UV could be reacting with either the matte medium or other bonding agent or with whatever dye is used. So it could be a combination of the two factors.
I’ve never had this issue with the WS ballast I have. Until a couple of years ago, I used Chroma 50 equivalent tubes (the Sylvania version). They are often used in store displays and may be low UV emitters because of that. I’ll do some checking around, see what I can come up with re UV levels from tubes.
I don’t mean to be rude, but would vacuuming restore the appearance? It’s surprising how much dust can accumulate in what we think is a clean environment.
Wayne
Apparently at one time, there was a theory that UV from tubes was causing skin cancer. This 1999 short paper from an industry group argues against that, saying 8 hours under the tubes gives about the same UV as a minute in full sun. Still, that’s enough that UV sensitive materials can be affected. in my experience. Doubt any skin cancer link, as it’s usually those out on the sun that get it, not working in the office: https://www.nema.org/Policy/Environmental-Stewardship/Lamps/Documents/LSD%207%20UV%20Radiation %20Fluor%20Lamps%20C7.pdf
From 2012, continuing concerns about the UV/cancer link, says the FDA recommends buying UV-protective coated bulbs (??): http://losangeles.cbslocal.com/2012/10/18/study-fluorescent-light-bulbs-emit-high-levels-of-uv-radiation/
FDA fact sheet on UV in CFLs: http://www.fda.gov/Radiation-EmittingProducts/RadiationEmittingProductsandProcedures/HomeBusinessandEntertainment/ucm116400.htm
However, there is good UV:
“…skin exposure to a fairly narrow band of UV radiation, UVB between 290 and 315 nm, can promote the synthesis of vitamin D, which is necessary for proper bone development and maintenance…”
http://www.lrc.rpi.edu/programs/nlpip/lightinganswers/fullspectrum/production.asp
A study of Iranian-market CFLs show things are pretty safe with them a 10cm in almost all cases: http://www.hindawi.com/journals/ijp/2015/504674/
What people who want to sell
With all the info that Mike posted…I think I’ll not concern myself, if mine does change colors…I don’t use fluorescent’s in the layout room, so I guess I’m stuck with what I have, but I don’t use matte medium…just use plain ole’ WS/Alcohol mix.
All this for ballast??? [:-^] [swg]
Take care! [:D]
Frank
Frank, what do you mean by WS in W/S Alcohol mix?
Rich
Wayne, it can get plenty dusty down in the basement, but I tried vacumming the ballast and that is not the answer. It has definitely discolored. I can try to take some quality photos and, hopefully, the discoloration will clearly show up.
Rich
Mike, when my cat gets off my lap, I will go downstairs and check the brand of fluorescent bulbs. I have 11 fixtures with 2 tubes in each. They are all the same brand.
Rich
I’m sorry… Woodland scenic’s ballast cement and denatured alcohol mix. Dries pretty quick, compared to other ways and is solid. Can be removed very quickly with plain denatured alcohol. I use the denatured alcohol a lot, use it on all the Tamiya acrylic’s that I air brush with so I get it by the gal. sizes, which are cheaper.
Take Care! [:D]
Frank
Frank, has any discoloring occurred on your ballast?
Rich
Humph…
Ballast on railroads DOES discolor with age. The reddish tint is perfectly natural and appropriate for railway ballast. Railroads are filled with iron dust from the brakes, from the couplers, from rust particles sheading from the cars, and all of this ends up on the roadbed and RUSTS there. The Ballast turns a dull red-brown.
Ergo your ballast is PURRFECT. Worry about it not at all!
Hey, Railroads live outdoors. Colors fade. And modelers are looking for the perfect color. The very idea!
ROAR
That’s it. I am now at peace. Unless you’re LION !
Rich