Minnesota
The Minnesota panel's state seal had been cut out in order to move it over to cover a damaged part nearby, with hopes of painting in the missing green state outline. Whomever did this quickly found out that the material covering the panel beneath was stretched over the wood, not adhered, so the hole warped and the seal wouldn't fit back into place. The warped and stretched material made it impossible to try reattaching the seal to the material as it didn't line up any more, and a substantial section of material was missing. Patching and using the original Kalistron® therefore was not possible, so the panel would have to be re-created. Luckily, the cut-out seal survived, so it did not have to be re-create it from scratch.
The Minnesota panel was missing its state seal — it had been cut out many years ago with the idea that it could be moved over to cover a damaged section and the missing green repainted in. Luckily, the seal was saved and was used to create a new version digitally.
The material covering the panel is Kalistron®, a vinyl product made by U.S. Plywood Corporation that was popular for architectural wall covering and luggage (among other things). Upon closer inspection I could see that the leather grain-embossed outer layer was clear vinyl, with a layer below that was printed on a metallic gold background, which was on top of silver backing material — an asbestos impregnated fireproof material. Needless to say, they don't make this stuff any more.
The state outlines and lettering were screen printed in green on top of the gold background, and the state seals were hand-painted where there was color or white, and overprinted with the black line work. The background color was a gold metallic color that may have been sprayed on as a base layer, or was a paper substrate. It's likely that the whole thing was then heat pressed under rollers to meld the layers together.
Years of exposure to cigarette smoke (nicotine) has added a brownish patina to exposed areas, and the nicotine seems to have seeped through the vinyl to the decorated surface below, so it could not be cleaned, but mitigated a bit using a method described below for the Manitoba panel. The photo below shows the difference between exposed and unexposed areas of the material.
Kalistron® is incredibly durable because the clear vinyl layer on top protects the decorated surface below, but its layered structure makes it nearly impossible to recreate. We considered trying digital printing on vinyl, but it wouldn't have the same gold metallic coloring and the imagery would be on the surface, and susceptible to damage.
A scarp of Kalistron shows how the areas exposed to air - and cigarette smoke - darkened over the years. The portion of the Minnesota outline shows the previous attempt to paint in green over the original color.
A breakthrough came about when I found a source for leather-grain embossed clear vinyl with an adhesive backing that's used for automotive applications such as dashboards and detailing. The colors could be printed or painted on a substrate cloth-like material, or painted directly on the wood panel, then covered with the vinyl, in the same manner that Kalistron® was layered.
Since there was only had one panel to make, it was decided to paint the gold background directly on the wood, then cut a frisket stencil and spray on the green design. The state seal was scanned and digitally reproduced. The panel was sealed with polyurethane and polished smooth before the clear vinyl was applied using a J-roller. This approach made for a unified structure that didn't create the problems of stretching material over the board.
The first step was to sand, seal and prime the board.
Next, the stencil was cut and the green areas spray painted.
The seal was applied and the whole board coated with several layers of polyurethane.
The final step was applying the clear vinyl covering and pressing with a J-roller.
The re-created panel looks almost like the others - except that it's cleaner and brighter looking because it hadn't experienced decades of being bathed in a nicotine haze, and fading from light exposure. Hopefully it will last another 70 years!
Manitoba PANEL
The Manitoba panel has suffered years of water damage, and the wood support plywood panel had de-laminated, and had to be replaced. The Kalistron® was badly streaked with stains, but the priority was to try cleaning it up and keep the original material.
Replacing the board was straightforward, but the stains on the Kalistron were a problem since the structure of the material with its clear vinyl outer covering protected the stained decorated layer below. Adding to the problems was the addition of nicotine staining that had seeped through the clear vinyl layer and stained the layers below. So, how to clean layers you can't reach?
Many cleaners and solvents were tried, but the Kalistron® was doing its job well by protecting the layers below, and nothing worked. But when I was trying out Soft Scrub, a bathroom paste cleaner that contained chlorine bleach, I applied a bit on a test area and let it sit for awhile and rubbed it off, and the covered area was a bit brighter below. The chlorine gas seems to have been able to penetrate the clear vinyl and react to the stain below. I could never get it to remove stains entirely, but it would make a noticeable improvement. With further testing it seemed that the reaction would take place in the first minute or so of application and leaving it on longer didn't improve the results. I'm guessing the chlorine does its work and then neutralizes pretty quickly.
The difference Soft Scrub makes can be seen in the area above the curtain clips and where an application was made. The method worked best when applied in small areas and removed after a minute or so.
The spot below with a bit of Soft Scrub showing how it can remove some, but not all of the nicotine staining.
Part of the challenge of these type of projects is figuring out how the original piece was made, and what materials were used. These closeup images of the Manitoba seal reveal that the colored areas were hand-painted as they show relief in the areas of coloring. And there are areas where the white behind the mountains had been applied a bit too generously, so green was painted over it to bring it back to where it should be. The seal was masked off from the Soft Scrub applications to protect it from unknown reactions with the bleach.
The treatments brightened up the panel overall, and lightened some of the worst stains.
More information about restoration projects are on the GN cars restoration page>>
