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Decals By Gerry Cole Version 10/6/08
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Decal Development• Traditional Silk Screen Decals• Dry Transfer• Letraset INT Process
– Intermediate Transfer Process
• ALPS Printers– MD-1000– MD-5000
• Kodak First Check Printer• Digital Silk Printing• Ink Jet Printers• Laser Printers
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Silk Screen Decal• Paper with water-based adhesive• Print inks through silk screen
– Print lighter colors first– Registration problems
• Paper expands with humidity• Second and following colors don’t match first one
across the entire sheet, some sheets are “bad”
• Apply lacquer clear coat– Plasticizer in lacquer
• Too brittle - cracks• Too flexible - stretches
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Silk Screen Decal Summary• Decal clear coat
– Too thick or too thin (fragile) – Proper amount of plasticizer for modeling uses
• Exposure to humidity changes during storage– Paper expands and contracts, while…– Clear coat doesn’t, therefore…– Clear coat cracks during water immersion
• Adhesive changes color – brown or yellow– Chemical reaction in the adhesive layer– Exposure to UV helps restore
• To trim or not to trim?– Even split within the club
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Dry Transfer• Dry Transfer is a term used to describe
decals which can be applied without the use of water or other solvent – Zip-A-Tone, Chart-Pak, Letratone, Letraset
• Flexible transparent backing• Printed decal• Wax adhesive layer• Apply pressure to release
– Push into model surface
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Letraset INT Process
• Uses solid color Dry Transfer sheet– Yellow, red, blue, silver, gold, black, white,
green plus custom colors matched to PMS #– White background under lighter colors
• Need photo negative of desired artwork– Expose Dry Transfer sheet under negative– Develop Dry Transfer– “Wash away” all but desired image
• Use as normal Dry Transfer– High quality, 300 dpi possible
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Letraset INT Process• Custom providers available
– Stamford Type & Color “STC”• Example, for single color per sheet
– Process 8” by 10” sheet, one of 16 colors, $49.75
– Negative from your artwork $20.00
– Custom mix color, 8” by 10”, $79.75
» Matched to PMS standard colors
• Provides 24 hour turnaround
– Suggest you use decals within 30 days– Check web for other vendors
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Letraset “Intermediate Transfer”• Since the Dry Transfer decal is “under” the
flexible transparent backing, you can’t “color” the image or modify it before application
• Intermediate Transfer lets you apply the decal to a special “transfer medium”– Decal may be colored with ink pen or spray
– Transfer decal back to a flexible transparent backing
• Apply colored decal as any Dry Transfer• Outdated today, but it did work!
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Dry Transfer Summary• No “silvering” problems – no clear coat!• Wax adhesive dries out, decal won’t release
– “Renewal” spray only partially effective– Try Microwave for a few seconds – heats wax
• Alignment difficult – Transparent plastic backing sheet stretches with use of
adjacent decals
• Hard to apply to curved parts• May not adhere well to rough surfaces• Apply Dry Transfer to clear decal film
– Probably the simplest solution for alignment problems
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Alps Printers• MD-1000
– Micro-Dry technology
• 300 or 600 dpi
• Prints well on regular decal papers
• 8” by 10” print area
• Ink colors– Cyan, Magenta, Yellow,
Black (CMYK), White
– Metallic Silver, Gold, Cyan, Magenta
– Finishing - Clear GlossMD-5000
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Alps Printer• MD-5000
– Added bright silver and gold foil print capability
– Update kit for Thermal Dye Sublimation printing
• Both versions have a variety of print modes– Business Graphics
– Graphic Art
– Photographs
– Monochrome• Photo
• Text
– Spot Color
– Metallic
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Alps Printer• Color printing – MD-1000
– Holds up to 4 ink cartridges, CMYK (K=black)• ALPS reads the bar codes on the cartridge to identify color
– CMYK inks are transparent, need white background
• Overlay Mode– Print spot color first (usually white)– Print second color with CMYK or Black– Seal colors with Finishing Clear
• Halftone or “Dither”– Amount of offset of colored dots – not visible to the
eye• Superfine, fine, standard, course, or no halftone• Photo Realistic print mode uses superfine dither
• Consider all the preceding as only a “Guide”
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ALPS Printer Summary• Horizontal “Banding” a problem
– Very common on MD-1000, less so on MD-5000– Factory alignment no longer an easy option
• Prints very well on decal paper• Need to cut out image without cracking decal paper at
the cut edge• Apply protective layer to decal?
• Adds to thickness and reduces flexibility• Reduces chance for scratches in the colors• Use only same base as original decal clear coat
– Microscale Decal Film usually very safe
• However, some colors still just don’t reproduce well at all (greens, yellow, orange)
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Kodak First Check• Up to 9 ink cartridges• Micro-Dry ALPS inks
– CMYK– New Orange, Green– Bright foil silver and
gold– Dull silver and gold– White– Black– Finish coat gloss
• Dithering like ALPS
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Kodak First Check• Since ALPS printers read cartridge bar code
– Can swap ALPS and First Check ink cartridges• Replace bar code strip• Why? ALPS cartridges getting very hard to find
• Good oranges and greens now possible• Banding less a problem than with ALPS• Expensive >> $2,500• BUT,
– Actually printing a decal with ALPS of First Check still a VERY time consuming process
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Digital Silk• Outsource decal printing
• Prints an opaque white
• Wide range of colors available– But selecting exact colors largely trial and error
• No metallic films can be printed
• Less labor-intensive for decal developer– Concentrate more on new decal designs
• DRAWDecals, Two Six, (UK), Model RR + others converting to Digital Silk
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Laser Printers• No white toner available
• Color Laser printers very expensive
• Prints on clear or white decal sheet
• Elevated temperature of toner “fixer” roller can melt the decal sheet and cause a messy (and costly) jam
• Image can “flake off” the clear decal sheet
• Attractive for Black decals
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Ink Jet Printers• White ink not available• Relatively inexpensive• Prints on special clear decal sheet
– Ink Jet inks are normally absorbed by paper • won’t work well on conventional decal papers without
modifications to the printer
• Decal papers available in clear and white
– A final clear coating required to protect the ink• Even when using special decal paper
– Inks are translucent, apply over white paint or decal
• Some club members have had good success
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The End