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Hey guys,maybe you can answer a couple simple questions.i work with resin a good amount and use super glue which works fine, but i've seen something called ca glue.what is that? Also on some of the new kits that come with whitewall tires or white lettered ones they call it pad printed tires.what does that mean and why don't they do it more often?they look real good.

thanks

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The concept behind pad printing is exactly the same as an ink pad and a rubber stamp.

Not quite that simple, Harry! In pad printing (AKA Tampo Printing) the soft rubber pad picks up ink (pigmented rather than dye oriented) from a plate which is photo-etched with whatever design is needed, and then transfers that "design" to the surface being printed. Usually thought of when discussing finished diecast models, a graphic design might be one color, or it might be multi-colored, as in racecar graphics, flame patterns, or even say, the Vee and Crest for a Cadillac model. In the case of multi-colored graphics or emblems, each color requires a separate pad-printing operation.

By contrast, an ordinary rubber stamp itself carries the design, as raised detail on the rubber surface of the stamp, picks up ink from a solf pad saturated with the stuff, and then transfers that design to whatever surface is to be printed, in the same manner as oldfashioned type in a letter press printing press.

Pad printed templates are created from artwork, by photoetching each part of each design as slightly recessed from an otherwise very smooth, polished metal (usually copper) surface. The first step is to add the pad printing paint or ink (as thick in consistency as probably a fresh bottle of Testors enamel), and then a squeegee scrapes all the excess paint off that photoetched plate, leaving the ink or paint in the recessed portions that were photoetched down into the surrounding metal. Next, the pad is pressed onto the plate, and picks up the color remaining, and then transfers that to the surface being pad-printed. In production, particularly with diecast model cars, this process takes mere seconds, and the paint or ink dries within a couple of minutes. This is then repeated, at a different station for each color, and each portion of the design or emblem, until all the colors are applied.

That's how it's done on diecast miniature cars, and even on molded plastic promo's.

Pad printing has limitations however: On a compound curved surface, as most car bodies have, if the pad-printed graphics are to "wrap over" curves, then the pad-print artwork gets divided into however many sections are needed in order to get a graphic that appears to have been masked and sprayed, yet in practice, is printed.

This is not generally used for doing say, a 2-tone paintjob on a diecast, however. That gets done by "spray-masking" in which process a masking template is made by forming soft sheet copper to the contours of the body to be given a second color (say, a white roof on a red '58 Impala), which is then cut out to make the shape of the color separation line on that body. Once this is done, the copper is hardened, and mounted in a frame so that it can be locked to an enclosed spray painting nozzle or two (or more depending on the scale and correspondingly the size of the model), Each time the operator positions a diecast body shell (with it's principal color already sprayed on and baked dry and hard) up against that mask, and steps on a foot pedal, the machine puts out a short shot of spray enamel onto the exposed area of that body shell.

Having spent almost 3-years in product development at Johnny Lightning starting a little more than 10yrs ago, I got pretty familiar with pad printing, and pretty quickly at that.

Art

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Not quite that simple, Harry! In pad printing (AKA Tampo Printing) the soft rubber pad picks up ink (pigmented rather than dye oriented) from a plate which is photo-etched with whatever design is needed, and then transfers that "design" to the surface being printed. Usually thought of when discussing finished diecast models, a graphic design might be one color, or it might be multi-colored, as in racecar graphics, flame patterns, or even say, the Vee and Crest for a Cadillac model. In the case of multi-colored graphics or emblems, each color requires a separate pad-printing operation.

By contrast, an ordinary rubber stamp itself carries the design, as raised detail on the rubber surface of the stamp, picks up ink from a solf pad saturated with the stuff, and then transfers that design to whatever surface is to be printed, in the same manner as oldfashioned type in a letter press printing press.

Pad printed templates are created from artwork, by photoetching each part of each design as slightly recessed from an otherwise very smooth, polished metal (usually copper) surface. The first step is to add the pad printing paint or ink (as thick in consistency as probably a fresh bottle of Testors enamel), and then a squeegee scrapes all the excess paint off that photoetched plate, leaving the ink or paint in the recessed portions that were photoetched down into the surrounding metal. Next, the pad is pressed onto the plate, and picks up the color remaining, and then transfers that to the surface being pad-printed. In production, particularly with diecast model cars, this process takes mere seconds, and the paint or ink dries within a couple of minutes. This is then repeated, at a different station for each color, and each portion of the design or emblem, until all the colors are applied.

That's how it's done on diecast miniature cars, and even on molded plastic promo's.

Pad printing has limitations however: On a compound curved surface, as most car bodies have, if the pad-printed graphics are to "wrap over" curves, then the pad-print artwork gets divided into however many sections are needed in order to get a graphic that appears to have been masked and sprayed, yet in practice, is printed.

This is not generally used for doing say, a 2-tone paintjob on a diecast, however. That gets done by "spray-masking" in which process a masking template is made by forming soft sheet copper to the contours of the body to be given a second color (say, a white roof on a red '58 Impala), which is then cut out to make the shape of the color separation line on that body. Once this is done, the copper is hardened, and mounted in a frame so that it can be locked to an enclosed spray painting nozzle or two (or more depending on the scale and correspondingly the size of the model), Each time the operator positions a diecast body shell (with it's principal color already sprayed on and baked dry and hard) up against that mask, and steps on a foot pedal, the machine puts out a short shot of spray enamel onto the exposed area of that body shell.

Having spent almost 3-years in product development at Johnny Lightning starting a little more than 10yrs ago, I got pretty familiar with pad printing, and pretty quickly at that.

Art

Like I said, the concept is the same as a rubber stamp. The rubber stamp takes the inked design from one place and applies it to another place, just like the printing pad takes the inked design and transfers it to another place.

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Not quite that simple, Harry! In pad printing (AKA Tampo Printing) the soft rubber pad picks up ink (pigmented rather than dye oriented) from a plate which is photo-etched with whatever design is needed, and then transfers that "design" to the surface being printed. Usually thought of when discussing finished diecast models, a graphic design might be one color, or it might be multi-colored, as in racecar graphics, flame patterns, or even say, the Vee and Crest for a Cadillac model. In the case of multi-colored graphics or emblems, each color requires a separate pad-printing operation.

By contrast, an ordinary rubber stamp itself carries the design, as raised detail on the rubber surface of the stamp, picks up ink from a solf pad saturated with the stuff, and then transfers that design to whatever surface is to be printed, in the same manner as oldfashioned type in a letter press printing press.

Pad printed templates are created from artwork, by photoetching each part of each design as slightly recessed from an otherwise very smooth, polished metal (usually copper) surface. The first step is to add the pad printing paint or ink (as thick in consistency as probably a fresh bottle of Testors enamel), and then a squeegee scrapes all the excess paint off that photoetched plate, leaving the ink or paint in the recessed portions that were photoetched down into the surrounding metal. Next, the pad is pressed onto the plate, and picks up the color remaining, and then transfers that to the surface being pad-printed. In production, particularly with diecast model cars, this process takes mere seconds, and the paint or ink dries within a couple of minutes. This is then repeated, at a different station for each color, and each portion of the design or emblem, until all the colors are applied.

That's how it's done on diecast miniature cars, and even on molded plastic promo's.

Pad printing has limitations however: On a compound curved surface, as most car bodies have, if the pad-printed graphics are to "wrap over" curves, then the pad-print artwork gets divided into however many sections are needed in order to get a graphic that appears to have been masked and sprayed, yet in practice, is printed.

This is not generally used for doing say, a 2-tone paintjob on a diecast, however. That gets done by "spray-masking" in which process a masking template is made by forming soft sheet copper to the contours of the body to be given a second color (say, a white roof on a red '58 Impala), which is then cut out to make the shape of the color separation line on that body. Once this is done, the copper is hardened, and mounted in a frame so that it can be locked to an enclosed spray painting nozzle or two (or more depending on the scale and correspondingly the size of the model), Each time the operator positions a diecast body shell (with it's principal color already sprayed on and baked dry and hard) up against that mask, and steps on a foot pedal, the machine puts out a short shot of spray enamel onto the exposed area of that body shell.

Having spent almost 3-years in product development at Johnny Lightning starting a little more than 10yrs ago, I got pretty familiar with pad printing, and pretty quickly at that.

Art

Art,

You really need to write a book on the model car industry, history and the like. Your knowledge is incredible.

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I used to work/repair a type of pad printer.It used a heat sensitive foil,and little numbers or letters held in a block that was heated, would press on the foil and imprint a date code. It was made by a company named Kingsley. I see them sometimes on ebay in industrial sections.

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Art I couldn't of said it better myself. I was a plant manager of a pad printing shop here in MN for 7 years. It is quite a simple process and fun. one of the few jobs I loved. But the nice thing about pad printed products is if you use the right inks on styrene the part will wear out before the ink does. Because the ink will etch(burn in is the termed we used) itself into the styrene and the nice thing in working with it we didn't have to flame or electroflux the styrene

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