I have two headlight lenses that are purple in tint. I think I read some where on the forum that this is due to the sun's affect on the "early" glass with lead in it. I did searches but could not locate the information. I have one that is
McK 19 (McKesson?) and one that is Les 56. I have some with no tint and wonder if giving them a sun bath will tint them.
Does anyone know how to identify the lenses with lead content using these codes?
I don't know anything about them, but if you go to ebay, Model T, newly listed items, then there is a purple pair listed. I have nothing to do with them, just saw them.
yes I see them, they are nice. Thanks.
They are Les 90 & 106.
That adds two more id's.
I'm told it has to do with the amount of cobalt in the glass which reacts with UV light.(sunlight) Some had more than others. Max Edmonds used to darken them by putting them in a foil lined box with a powerful UV lamp. Said it took weeks or more and a lot of KW's.
Be advised you may not like to drive at night with dark purple lenses. I didn't. You lose effectiveness of alreadly marginal lights. Mine all go to ebay.
I had some old glass doorknobs I laid on our flat roof for a month or so. Darkened them right up.
Its not cobolt, its MANGANEESE. The true color of glass is green like a COKE BOTTLE. Manganeese was used to clear up the glass but it was found to eventualy turn the glass purple. Many, many bottles in antique bottle collections are purple.
Many Model T Owners pay higher prices to purchase purple head light lenses. The average selling price for purple headlight linses are double what the clear one sell for.
The problem with purple lenses is that they shut off some of the already dim lights of a Model T. if you are driving at night.
Easy fix. Have two sets of rims and lenses. One purple and the other clear. Then if you are going to drive at night you switch. I did that before the Kanab tour. My lenses were purple, and I switched with another of my T.s which had clear lenses. We needed the lights for the tunnel. It was still hard to see, because the tunnel had "windows" and every time one would pass one of the windows, the eyes would adjust and then had to re-adjust again to the dark. But we made it through in both directions.
The eye adapts to light quickly, and to dark slowly. If you are presented with bright light of short duration after being dark adapted, close one eye if possible.
That's what they taught us somewhere in the Army.
Thank you all for the feedback and help.
The Violet lenses look really great on my Plum and Black fendered runabout. I found some violet side llight lenses too. I don't get out much at night, but that is good insight.
Picture of my runabout