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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