Help with screen printing water slide decals

Hi guys,

I don't usually post here, but thought someone amongst you might be able to help me.

I've started making bicycle frames (full-size ones), and additionally am restoring a really old racing bicycle. Both tasks require me to make water slide decals to decorate the frames. In the case of my own frames, I have a lot of latitude as to what I do, but in the case of the restoration I'm trying to duplicate the original transfers as accurately as possible.

I read everything I could find on the net about making decals, and decided to go with a screen printing process, as I've never in my life seen an Alps printer, and need to be able to print white (not to mention being sceptical about the ability of inkjet inks and laser toners to survive in the sunlight for any appreciable time).

My first try is a four colour transfer for a track racing frame I've recently built. See

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for a few details. I designed the artwork in Corel Draw, and set about making screens.

The screens I'm using are all 77T, except for the last colour (black outlining) for which I bought a 100T screen. I bought sheets of decal paper from Bel Decal. I asked for decal paper suitable for silkscreening, and they sent ink-jet decal paper.

I coated the screens with emulsion (Ulano LX660 dual cure diazo photopolymer), left them for 24 dours to dry, and then exposed them with my artwork and washed out the unexposed emulsion. So far so good, though I did have a few areas on the screens where the emulsion was thicker which dried with a sort of wrinkled appearance.

I left them overnight to dry, then tried a test print, with just one colour and my finest screen. I used "artists acrylic", which I bought from the local artists supply shop, with "printing gell", as recommended by them for silk screening.

My first print, on paper, worked ok (though was fairly light). I tried a second print on the decal paper, and that's when the wheels fell off. The decal paper adhered itself to my screen with astonishing veracity. When I tried to remove it, the decal film seperated from the backing, and some of the emulsion came adrift from the screen. The print was terrible. there wasn't nearly enough ink where there was supposed to be ink, and fine lines didn't come out at all.

So what am I doing wrong? Is the water based paint causing the adhesive on the decals to go? Is it an issue with humidity (it's been very humid in Sydney the last couple of weeks)? Should I use enamels rather than acrylics?

Regards,

Suzy

Reply to
Suzy Jackson
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Reply to
David Calhoun

Suzy, For help with the silk screening process, check with your local community arts organisations or possibly local city council for specialist art print groups or workshops. They commonly use that method for limited edition printing. Having visited a local group myself on a similar quest I decided there was too much wet material around to go well with waterslide decal paper. You might also consider a clear peel- off / press- to- apply self adhesive vinyl film as a medium, which is what most UK bicycle manufacturers supply when I've requested new decals for restorations. Laser printing works really well, except for its lack of ability to deal with white. Often it's possible to cut out a white undercoating decal to overlay the colour layer onto. It's a good idea to increase the durability by overcoating with a clear varnish or lacquer to finish, but be sure to test for compatibility beforehand - I've had ink dissolve with one brand of acrylic lacquer spraycan. There are anti UV coatings available from your local autostore/carshop for vinyl and such like products which can be wiped on afterwards to protect the pigmentation. Alps printers are allegedly very good, though I've never seen the results in person, but close up photographs show impressive definition. Before buying one though, I'd suggest contacting Mike Grant at

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either request a sample or send your artwork file to him for appraisal - it may at least give you a precise and cleaner alternative to wet silk screening. Hope this helps Chek

Reply to
Chek

Wow Suzy ! You really dove into this decal making stuff all the way!

I can't help on the screen printing part (although I suspect that the water based paint might be the culprit). There are more decal paper manufacturers out there - might give them a try. You might also want to ask for decal paper with thicker clear coat. It might be less affected by the water based paint. Also, if your decals are large, thicker clear layer might be beneficial (it won't tear easily when being applied).

Try:

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can provide you with decal paper (with thin and thick clear coat).

Alps printers on the other hand are alive and well (even if they aren't sold retail anymore). Many decal makers do use them. Try:

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You might ask around there and if you provide the artwork, they might make you those decals for a reasonable price (on Alps printer of course).

Those decals shouldn't fade. They might be a little more fragile than silk screened ones though.

HTH, Peteski

Reply to
Peter W.

Suzy, There are a lot of variables to deal with to get success with waterslide decals. They need to be printed with lacquer based inks, humidity must be controlled to maintain proper registration between colors, etc. Having watched a good friend who owns a screen-printing business print them (both for models and for a local bicycle restorer,) I'm convinced that it's a job best left to the pros. Just my opinion, Jim

Reply to
Jim Hockett

An Alps isn't an ink jet, it's a thermal wax. The decals, if properly over coated, last for years without apprecable fading. Did some for my bike 3 years ago now and they're still good.

wrf rdec water slide decals WRF

"Nooooooo! Stop me before I build again."

Reply to
rfranklin

If you have CorelDraw artwork, why not give Alps decals a try? I recently had a Letter sheet full of decals printed by Tango Papa decals from CD8 artwork for a very decent price, and excellent quality.

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There are more small companies offering custom Alps printing. I've understood Alps decals are sun and weather proof.

Rob de Bie

My models:

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Me 163B site:
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Reply to
Rob de Bie

Hi guys,

Thanks for the suggestions. Although it's tempting to get the decals printed with an Alps printer, I'm keen on using the silkscreen process, and have already put a fair amount of money into screens, squeegees, emulsion etc.

Further tests have shown that the acrylic paint is no good for decals. I waited a few days until the humidity had dropped somewhat and had another try. This time the decal didn't stick to the screen, but the print quality was fairly poor, with sort of blotchy areas where the ink should be.

I've ordered ink designed specifically for for screen printing on decals, from Australian Specialty Inks, here in Sydney. These are relatively cheap, at around AU$55 per litre, though unfortunately the smallest conatiner they sell inks in is 1 litre. This ink isn't water based, so with luck will work much better.

Now I'll have a lifetime supply of black, white, blue, and orange ink.

Regards,

Suzy

Reply to
Suzy Jackson

[snipped]

I don't know what quantities that Sericol (UK) used to sell it in but we used to use it in BBC Engineering for front panels and for masking printed circuit panels. It was damned near bomb proof.

IIRC, they also used to make that red photoactive gel on large film for making silk screen masks so that might be another source.

Richard.

Reply to
Richard Brooks

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