Discussion in 'Tools of the Trade' started by Darwin, Jul 30, 2004.
Acrylic Hard Modeling Paste...,
Who makes it and where can it be obtained?
Gil is trying to corner the market before he tells us all.....
I don't know, but am I missing something here? All this talk about what is best for a metal look and how to adapt it to paper models and all when there is this stuff? http://www.bare-metal.com/
Taking a break from further experiments. Still haven't made a full page, that's next.
The product I'm using currently is manufactured by Golden, Gel Mediums, Hard Molding Paste. Gel Medium Modeling Pastes are used in art for building up texture of paints and as a glue for paper mache. I use Golden as it's usually lower in price than Liquitex which offers comparable products. I use Liquitex Gloss Medium & Varnish as a thinner for the above product. Do not thin with water as it changes the shringkage coeffeicient yielding undesirable effects.
The aluminum foil needs to be prepared prior to bonding. Again, you need an adequately sized clean glass pane for rubbing or burnishing the foil to smooth out wrinkles. Use a chamois or cotton cloth and rub from the center in one direction toward the edge gently holding the edge to prevent movement. Rotate the piece to smoot out the other side. If a small bump appears it means that a piece of dirt is underneath. It must be cleaned off before gently burnishing out the defect. Keep a sharp single edged razor to run over the glass to insure that the surface is clear. The foil needs to have it's surface cleaned with alcohol removing any contaminant that will prevent bonding.
Spread the acrylic molding paste over the surface of the paper and roll out with a printers roller till a fairly even layer coats the paper. Small pieces can be simply done with a small spatula or squeegee. Place the pasted paper on top of the foil rolling it down from the middle to the outer edges to prevent trapping air. Turn the laminate over and burnish the foil from the center toward the outer edges with either a chamois or cotton cloth. Let dry overnight before coating with PVA for printing (which I haven't done yet...,).
I've thought about printing on the paper side of the laminate and then cutting out the sections and applying panel lines and rivet detail from that side. But this is another subject all together.
Bare Metal foil is geared toward plastic modelers and can probably be used for paper models. 3M Aluminum metal tape mentioned earlier is probably an easier substitute and is widely available at your local hardware dealer. This tape is delivered dead soft and forms well over complex shapes. One tip is to gently warm the surface of the roll with a heat gun or hair dryer to loosen the adhesive before removing a section. This prevents "chatter marks" from forming which would have to be removed through burnishing.
The quest is to find a card stock that looks real when "printed and assembled into a model". Letraset is only available in the EU and aluminum foil paper is not offered in the consumer space leaving little choice but to develop your own. Besides that it's been fun and I just go into the kitchen and simply pull out a couple of feet of whenever I need some (short order process). One other point is that this technique will work with any metal foil. I use K&S Metals foil for other projects but that isn't paper and you all must remember, "Did I tell you that's it made from paper?"....,
I also use Gloss Medium & Varnish to make my own magic modeling paste. I mix it with micro balloons to make a paste mixture which is light and adheres well to paper. It's good to seal the paper first with either acrylic matte spray or lacquer to keep it from "sogging out".
That's all for now....,
Best regards, Gil
P.S. Corner the market? Jeez....,
As luck would have it I just discovered a source of metallic card stock! It's not coated for inkjet printing but has the same appearence as the Lectraset. I rollered the aclcohol-water glue stick coating on it, put it in the drying oven at 125 degrees Fahrenheit to dry for 10 minutes. Put it in the Canon inkjet and printed the first page of FG's Dakota. The result was put back into the drying oven followed by a coating of matte acrylic sealer. The source has several varieties to choose from (I ordered a minimum of 250 sheets picking it up tomorrow).
Now the bad news, they're not going to carry it any longer and the replacement stock just isn't in the same class. They carry another manufacturers stock but need to order it. I'll probably do that tomorrow.
The source is Kelly Paper Inc. website: http://www.kellypaper.com and they accept online orders but limit it to North America. The paper type that I ordered is called Cadillac 2000 Silver Item No. 5676H. The site doesn't contain photographs unfortunately. If you want I'll post some photographs for your perusal.
Best regards, Gil
Still trying to improve my homebrew inkjet coating method.
Settled on a mixture of 3M glue stick (vinyl acetate), water and methyl cellulose (used in to strengthen paper fiber in production and as hair gel). I roll it on with a small fine texture roller and then dry in a drying oven set at 125 degrees Fahrenheit.
The inkjet ink does not surface bead but adheres well with dot growth now contained. Surface penetration is not what I would want it to be but is sufficient for now. The print is still delicate and must be handled with care in transport to the drying oven to dry the ink. It's then sprayed with a protective acrylic matte fillm. This method seems to work for just about any printable surface.
Research on this subject and has found that the item in question is called "polyester receptor coatings for inkjet printing". I'll be speaking with some local experts next week in an effort to see if there's a local jobber that is willing to coat small lots (<1000). If anyone knows of a source for the receptor coating please let us know. This would make a great spray can product beyond just the card modeling application.
Now to see if anyone wants metallic paper?
More as I make it, or as it comes in, which ever...,
Best regards, Gil
Interim results report...,
Don't use the vinyl acetate (glue stick) and methyl cellulose as an inkjet coating. The inkjet does print well on it but it doesn't hold up well enough for modeling puroposes. Still researching a good solution for this.
Will be getting some metallic card from the UK in a few days so I'll be able to do a side by side comparison of all those that have been collected during this investigation. I'll report on those after their received in the mail.
Best regards, Gil
A test using PVA based glues has provided interesting results. Simple white glue rolled onto the problem card stock seems to work well. Getting it to coat well without texturing is still a point of developing art. I printed out Nobi's Saab on test sheets and took some close-up photographs which are shown below. Note the speckle areas in the green fill where the print ink failed to adhere to the surface. The surface texture mottle needs to also be reduced. I believe both to be a coating application issue.
Direction now is to to investigate an addititve which keeps down the tendency of the coating to form bubbles during the rolling process. I tried thinning with water finding that this inhibited the adherence of not only the coating but also the ink. The PVA has to be rolled full strength to achieve fair results. I have some alcohols that might be compatible but haven't tried them yet. Isopropyl and denatured alcohols react with the PVA to form some sort of polyvinyl plastic that doesn't take the ink at all but acts as a varnish instead.
More to come...,
Best regards, Gil
Then you did find a new product? a varnish coat?
One alcohol worked as a thinner for the PVA. Mixture applied smoothly forming an adherent and conformal coating of the surface. Dried surface has a slight gloss.
Inkjet print applied smoothly and with high surface reflectivity. Some bleed of black lines into areas of green were noticed; printhead overdrive in high saturation areas are suspect. Finer control of the print output is needed to solve this problem. Printed sheet was dried for 15 minutes at 125 degrees Farhrenheit after which the ink was dry and stable. Print quality is on a par with photographic paper exhibiting a gloss reflective surface.
Topcoat protectors haven't as yet been applied but aren't expected to be a problem.
In summary this is as good as any inkjet receptor media that one could reasonably expect to make from readily available source materials. It remains to be used in the assembly of an actual model but again no problem is expected.
Best regards, Gil
P.S. It's not a varnish coat. Correct terminology is an "inkjet receptor coating media" and yes, it's a new product.
Nobi's Saab J-21 looks great printed on the new media coating. I printed on the Cadillac silver cover stock which reflects back through the ink layer giving the print a vividness that's just not achievable on paper. The surface is glossy like photogrphic paper and the ink is unbelievably stable.
Next step is an experiment with dry transfer decals...,
Metallized Paper: Try This
Gil: Try cutting the PVA with acrylic Matte Medium/Varnish, mixed with a few drops of Acrylic Flow Medium: I'd suggest a 2:1 ratio, diluted with a bit of distilled H2O. VERY thoroughly mix the medium with the PVA, then apply to the stock in a very thin layer (such as, with a squeegee) and allow to dry. Use plastic food wrap to separate sheets of stock, and press them while waiting for them to dry.
Stay away from alcohol as a drying agent when working with PVA. It is, as you have observed, NFG.
Flow Medium is nothing but high-class detergent: it breaks down the surface tension of whatever it is mixed with, allowing uniform penetration of the surface to which it is applied. Liquitex and Jo Sonja (Chroma Acrylics) are well-known brands: any good Art Supply store should have it.
One caveat about this coating..., it needs to be protected by a topcoat of crystal clear or matte spray finish. It is easily damaged by water in the same way as photographic inkjet paper.
I forgot to explain the application method! I use a foam mini-roller that's intended for applications where very smooth finishes are desired. Extra rollers are sold separately and it's a good idea to buy several packs as it comes in for the occasional touch-up around the house as well (another way of sneaking it into your hobby budget). I premix the approximately 80% PVA white glue and the 20% Polyvinyl Alcohol (PV Alcohol is used as a mold release for polyester and epoxy castings and can be found in shops that cater to those applications areas) . This is then added to a 2 quart flat bottomed pyrex cooking dish that I use as a rolling tray (easy cleanup). The roller is rolled in the mixture to coat and then rolled to even out the distribution on the roller. An old cardboard box is used to roll out the first strokes to even out and dry the amount the roller will apply to the card stock to be coated. The roller needs to be almost dry to achieve a nice even coating of the card surface otherwise you'll end up with a bumpy surface. The first pass will only partially coat the surface. After several passes the coating will be spread and evenly coat the surface. I use a piece of rubber gasket cloth underneath for ease of cleanup. Wipe this off between coatings otherwise the card will begin sticking to it (yes, you can use it to laminate with also). When the coating is nice and even and shows a nice even sheen against the light it is placed in a drying area for several hours until completely dry. The dry surface will have a nice
gloss/semi-gloss sheen and are ready to for the inkjet printer. Remember to let the ink dry after printing for several hours and then coat it with your choice of topcoat.
Tim sent me an email with an very interesting product which will be the next subject in this Topic series...,
Best regards, Gil
I tried mixing the acrylic varnish with the PVA and the results were disapointing. The ink failed to adhere to the surface which is a clear indicator that something is very wrong with the receptor chemistry.
Successful candidates for coating have to exhbiit -OH radical attachment points for compatibility with water based inkjet inks. Some of the base radical series of Polyamides and imides are used for coatings for this reason.
A product group with those attributes is next in this Topic Series.
Best regards, Gil
Jim, I had second thoughts about this and went back to my notes and realized that I had mistaken another mixture for a PVA-Acrylic combination. A mixture of half PVA and half acrylic gloss medium varnish was mixed well and then used to coat the problem surface using a roller.
Guess what? Your idea works extremely well! In fact better than using the PV Alcohol to reduce the viscosity of the rolling mixture. The print not only adheres to the surface but exhibits zero pinholes in filled areas! Thick black lines still exhibit a ragged bleeding into filled areas which I believe to be an overdrive issue related to the print driver. The surface texture is semi-gloss and has a texture mottle which is an artifact of the coating method (see first photo below). It's weatherability is still in question but will probably be much better than with the PVA alone.
I've also attached a photo of a wright cyclone R-1820-97...., sorry for the quality of the photograph but this was printed on a bulk piece of photocopier overhead film ($0.05 a sheet in bulk). It was placed on a sheet of metallized cover stock to take the photo. This formula seems to work well on a variety of surfaces that were impossible to print on before and the ingredients are available World Wide!
Thanks Jim, Gil
P.S. Anyone else try this yet? I am using a Canon i560 and would like to get feedback on whether HP and Epson inks are also compatible with the coating.
I was wondering if anyone in the U.K. is familiar with a product offered by Bright Ideas which used to be called Ultra Foil when it was offered by Reynolds (Alcoa) before the line was sold to Bright Ideas. This is aluminum foil paper with a plastic coating. It may be too "chrome" to do anything with but I want to chase it down just the same.
The other interesting discovery is that I had a roll of aluminum foil paper for the last several months and didn't realize it. It came in the form of silver wrapping paper. I finally took a test sample and simply burnt off the paper to see if the foil remained. It did. The paper has a shiney surface but is mottled by the varying paper thickness to which it is bonded. The foil thickness is very thin being under 0.01 mm which is probably too thin to serve well as a candidate for card modeling.
I am still waiting for Post from the U.K. containing sample stock. I'll report on the aluminum card stock surveyed so far then.
Best regards, Gil
Back again for an update,
The silver wrapping paper mentioned earlier takes on the appearence of aluminum sheet when buffed with a Super Fine #0000 steel wool pad. It passes the test of being put next to a sheet of similarly treated aluminum not being discernable as wrapping paper. The foil is less than 0.0005 inch thick and can't be worked like thicker foils.
Need to go back and pick up a few more rolls from Michael's tomorrow (it was fairly cheap). This is Aluminum Foil Paper and can easily be glued to card stock for models requiring an aluminum surface. This stuff was in my way all this time and it never occured to buff it with steel wool...,
P.S. I have visions of many of you being caught buffing wrapping paper with steel wool in the middle of the night...,
Printable Silver / Metallic / Aluminium paper?
See also the thread "Boeing 707-320 PanAm 1:120 scale finished!" under "Designer´s Corner" for a further discussion on this subject.
Here is a picture of my make of Kampflieger's Blohm and Voss Ha 137 in 1:32 scale and made from aluminum construction tape.
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