Priming laser printed models

[John Wagenseil]

I recently bought a color laser printer, and am very satisfied with its print quality, the colors come out nicely and small detail is reproduced accurately.
However, the first laser printed paper model I tried to build was awful. The printing was fragile and easily scratched or flaked off the page, and the pigment layer broke off along folds.
I spray painted the sheets with Krylon clear spray, the printing held up much better, the pigment did not flake off the paper, but the surface of the paper was left slightly glossy and did not accept glue or water colour paints. (I was able to glue up the model using organic solvent based tube glue. White glue would not stick to the varnished side of the paper.)
Then I tried Aleen's Matte Decoupage. I brushed on a thin coat over the laser printed parts using a broad soft brush. I let the page dry, sandwiched between two weighted sheets of Corian to keep the sheets from curling. The Laser print pigment did not flake or scratch off when handled, was resistant to cracking at folds, and the coated sheets glued easily with white glue, CA and contact cements and could be over painted with water based paints .
I used Aleens, but Modge Podge or Deco Art would probably work just as well. Thinned gesso medium for acrylic paints might also work as a primer for a laser printed paper model.

[richkat]

Check and see if there is a setting for thick paper, that will slow down the fuser and stick the toner to the paper a little better. Most laser printers have this setting. Also when I coat printed pages i always cut off the glue tabs and make new ones with uncoated paper....Rich

[mbauer]

Hi John,

You just discovered the major flaw with "most" laser printers.

The "ink" is nothing more than "toner" made from plastic. The laser's job is to super heat the toner and then it gets sprayed onto the paper. It bonds to the paper as it cools. It doesn't enter into the paper layers like ink does, but lays on top.

Not sure how you can seal it to the paper for bends etc...

I use ink, so the following suggestion hasn't been tried...Maybe if you heat the printed paper before bending it might stick. A steam iron and a layer of paper/cardstock on top might be enough to trick the toner into making the bends.

Some builders here have had great luck with different brands of laser printers. Hopefully someone will answer your questions with what works for them.

Good luck with your projects!

Mike

[cfuruti]

Originally Posted by mbauer

Hi John,

You just discovered the major flaw with "most" laser printers.

The "ink" is nothing more than "toner" made from plastic. The laser's job is to super heat the toner and then it gets sprayed onto the paper. It bonds to the paper as it cools. It doesn't enter into the paper layers like ink does, but lays on top.

Mike

Actually the toner is usually a dry powder which clings to paper in areas charged with static electricity. Only then the paper is heated causing the toner to fuse and stick to the paper - in other words, much like Xerox except the static charge is cleared in white areas by a raster-based laser instead of light reflected from an original.

Otherwise you're correct, the toner does not penetrate and easily cracks and flakes off the paper where creased or overhandled.

I thought laser printers were rather useless for all but the simplest paper models; that's unfortunate, because the output of color lasers is usually brighter than that of inkjets, and large dark areas don't curl thin papers. John's tip could be a blessing.

BTW just the other day I was erasing an old laser-printed slider - the acetate-like plastic sheet has the right thickness for a project. The sheet is coated with a kind of varnish (I guess toner, even melted, does not stick directly to plastic) which is fogged then removed by alcohol, leaving the plastic completely clear.

[John Wagenseil]

Originally Posted by richkat

Check and see if there is a setting for thick paper, that will slow down the fuser and stick the toner to the paper a little better. Most laser printers have this setting. Also when I coat printed pages i always cut off the glue tabs and make new ones with uncoated paper....Rich

Thanks,
I did try the thick paper setting and the "improve toner adhesion setting" but flaking still did not completely go away and printing still was suseptible to being scratched. The decoupage liquid seems to glue the laser pigment to the paper surface. Once I had applied decoupage liquid and let it dry, I was able to carefully rub off glue smears without damaging printed surface.

[ashevilleangler]

John,

How did you prevent the corian sheets from sticking to the wet decoupage?

Curt

[John Wagenseil]

Originally Posted by ashevilleangler

John,

How did you prevent the corian sheets from sticking to the wet decoupage?

Curt

Funny you should bring that up.
I did another few laser printed sheets and just found out the hard way Corian seems to have a smoother side which will sometimes (but not always) peel off cleanly from the paper, and a rougher side which the paper usually sticks sticks to. I was using Corian because I had a couple of pieces in the kitchen that I was using as trivets and it was heavy and I was hoping it was going to be non stick.
Next time I will try either a very clean sheet of glass, or experiment with wax paper, or try using the underside of a flat shiny stainless steel baking pan as a paper weight.

[clif52]

If you have a local sign shop that prints on vinyl, the backing sheet they peal off when installing it is great for putting on each side after coating. It will not stick, and peals right off. The thin plastic backing from sign laminate is great too, but very thin. I've used both even coating jigsaw puzzles it peals off. I reuse it over and over.
Clif

[John Wagenseil]

A trip to a kitchen store yielded:
2 pack of flexible cutting sheets. These are good non stick surfaces to do glue ups on.
A flexible vinyl icing spreader. A non stick squeegee for spreading glue, or as tool to smooth paper sheets after they have been glued up.

And from the school supply aisle at the supermarket:
Elmer's Clear School Glue
I put a laser printed page on one of the cutting sheets, squeezed a blob of Elmer's Clear School Glue onto it, and used the icing spreader to smooth the glue over the entire page. After the glue dried the page peeled off the cutting sheet without any difficulty. Elmer's Clear Glue dried to a semi gloss, gives the page a plasticky feel, prevents cracking and flaking of the laser print pigment from the paper. The glue treated page is glueable, there is a brief time where excess glue can be wiped off. If you don't mind a glossy surface, Elmer's Clear School Glue, appears to be a good material for priming laser printed models to strengthen the paper and prevent the printing from flaking off.