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As a new crafter I am wading into PM and open to trial and error (hopefully not too many of those). I ran into a couple of problems on embarking on my first couple of projects. Hopefully they will be avoided as I become more experienced, so I look to this community's advice.
* Using Jonni Good’s paper clay recipe, the pulp proved to be too sticky, maybe due to too much glue. What could be done to remedy such a situation? Do I add more paper, flour or dry wall mud, and is there a risk in offsetting the ratios of the mixture that could result in a finished project crumbling, cracking or some other horror?
* I would wet my hands from time to time as I molded my bowls which handled some of the stickiness. I'm concerned (not to much since it was so little water) that I could affect the recipe's ratios with the added moisture. Could I have done so and what could be the result?
* Should my measurements be in dry or wet ounces? That might have been the issue of too much glue causing the above.
* I had a lot of difficulty using cling wrap (store brand) to cover a bowl I was using as a mold. It proved difficult to get it to cling to the interior of the bowl. It became even more exasperating when I tried to use a low profile bowl that had scallops shapes around its curved sides. I wanted the wrap to conform to the shape but I couldn't get it to work. Could some of this be remedied by using a major brand like Saran Wrap (would it cling better than a generic brand)?
* What’s better in terms of a release on a mold – cling wrap, petroleum jelly, wet (non-glued) paper, tin foil or some other material/technique? What are the relative merits or faults?
I did work around some of problems I encountered (like my second note above) but I don't know if bowls will turn out properly; I have five pieces drying. I plan on making some more paper clay tomorrow and hope to avoid the issues cited above
Thanx - irv
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Mixing a dry, fluffy material and a liquid can be tricky due to variances in the dry material, such as how packed (or not) it is, or how well it absorbs. The best thing seems to be to start with about half of the liquid (adhesive) that you think you'll need for the amount of dry material. Work it in well, take your time. Then let it sit for a few minutes to absorb. If it needs more adhesive, add just a little more and mix it well, then repeat in small amounts until you reach what consistency you want. If you make it too soupy, you'll have to add the dry ingredients in the same ratio as you started with. One trick I was slow to discover was to mix all the dry ingredients together well, then set some aside as a reserve to 'fix' a too-moist mixture.
Wetting your hands won't cause any trouble unless you over-do it. Keep in mind that moisture is evaporating as you work.
Using wet or dry ounces is usually determined by the individual material, dry ounces for dry materials, wet for wet. But when you're dealing with an individual's recipe, you'll never know for sure unless they specify.
Keep in mind that recipes are just estimations with PM.
Cling film or plastic wrap can be frustrating because it is designed to stick to itself, not most objects. Try another product called Glad Press 'n' Seal food wrap. This is a heavier plastic film with a tacky adhesive on one side. Keep a small pair of scissors handy to slit the material so you can overlap excess material on curves smoothly, or apply it in multiple overlapping pieces (like strips of PM).
But keep in mind that PM doesn't really stick firmly to some plastics, depending upon your adhesive. Mix up your PM and then take a small piece (fingertip-sized) and press it directly onto your plastic mold (or try a strip w/adhesive) and let it dry. When dry, does it come off easily? If it does, you probably won't have to use either plastic film or a release agent. Note: this only applies to plastics, not glass, ceramics, wood or metal.
Release agents differ mainly in how they are used, and how they will relate to the finished project:
1. Petroleum jelly or oily materials: Your main consideration in using these depends on if that surface is going to be a visible surface when the project is finished. For instance, if you put a light film of petroleum jelly or oil on the inside of a bowl, and pressed your PM onto it, that surface may have a problem accepting more PM onto it, and it may interfere with the finish of the surface if you're using paint, stain or sealer. Those may fail to stick in random patches.
But if you use an oily agent on the outside of a form, you will cut off the form and reattach it so the oil-affected surface remains inside your project and out of sight, it shouldn't be an issue.
But when you do use an oily release agent, only use a VERY thin coating, the thinnest you can manage. More is definitely not better!
2. Cling film/plastic wrap will almost always release quite easily from both the mold and the form you make. But it can be a nuisance to handle and won't stick to most surfaces. Tape may be the most effective way to hold it in place. Try the adhesive-backed Glad (brand) Press 'n' Seal food wrap.
3. Wet, non-glued paper is often the quickest and easiest of all. Damp paper sticks to most hard surfaces. But without adhesive, it releases easily when dry. Damp or dry, PM adhesives stick to it. As long as you keep it damp, you can apply it in pieces as overlapping layers, but they will fall off if it dries out. Keep a spray bottle handy as you work to apply your first adhesive layer. Immediately cover the plain paper with another layer of adhesive-coated strips just to get the mold covered. If it is your intention to form the main project from pulp PM, just stick it to the first layer of adhesive-coated strips. If you try to apply pulp PM to the plain unglued strips, the work is likely to fall apart if gravity is involved.
4. Tin (aluminum) foil will mold around many shapes without any (or much) adhesive (a bit of tape in strategic places can help). Some of the adhesives (esp. the organic ones) won't stick to it much when dry, so it can be removed fairly easily. It can be formed into firm lumps and even specific shapes to create lightweight bulk. It can be attached and left inside the project forever without any damaging effects. White (PVA) glue tends to stick to it rather tightly, so keep that in mind.
5. Another material that might be useful for certain things is baking parchment. This stuff resists anything sticking to it, wet or dry. It is only good for forming flat decorations on a table, like decorative tiles. If you try to use it vertically (even approximately), your PM will slide off. I mean NOTHING STICKS!
6. Lightweight cardboard (cereal box weight) can be cut and taped together into simple shapes to form a permanent base that remains inside the project. Cover it completely with masking tape to protect it from moisture enough so it doesn't sag or collapse while you are applying the PM to the outside.
Practicing on small projects and shapes will show you what is best for what type of shapes and materials. Whenever you have some leftover material, try it with something new and expand your repertoire of tricks and methods. Keep them simple: less than 6"/150 mm, and in simple shapes.
Sue
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Sue is totally amazing. (Seriously Sue, I think you've already written at least one book with your posts on this site.) ...
Here's my take:
re Jonni's recipe: I added more dry ingredients when it was too wet. (Initially I added more chalk and flour. Now, as I mentioned before, I leave me shredded paper dry, and mix it in by the cupful until the clay is the consistency I like. If you end up with more filler (chalk, plaster) than paper your clay will be a bit more likely to crumble ... but play with it and see what you think.
re releases: I concur with Sue's info above. I tend to use no release on plastic forms like bowls (but then use the inside of the bowl, as mache tends to tighten a bit when drying -- this way it pops out easily. Also, I often use 4-6 layers or so strip mache to copy the form (bowl, sculpture, etc.) then remove this from the mold. 4 layers will typically be strong enough to hold it's shape so I can add a detail/firming layer of clay. With the combination of the strip mache underneath, even slightly 'crumbly' clay will be strong once it dries.
Again, experiment.
I tried using plastic wrap as my release on a mask mold once. I was really frustrated that I couldn't get it smooth, and the mask ended up having all these crevices and grooves from the plastic. I saved it, of course. Came back to it 6 months later and loved it ... loved the creases, etc. My point being each release has it's own strengths and even the mistakes may show you something you weren't expecting.
On my plaster molds, I rub in a thin coat of paste wax before adding in my paper mache. I do this each time I cast. It's possible it's overkill now (after 10-12 casts), but I'm not willing to ruin my mold discovering I'm wrong. : )
-- b
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A big MEOW!!!!!! to Sue (a/k/a Catperson) and ditto to 'b' for ALL the GREAT advice.
Today was my second day of crafting/experimenting. I did add a bit less glue to my pulp and it proved less sticky and more manageable.
I also tried a light coating of petroleum jelly on the outside of a small glass bowl that I used as a mold. Yesterday (day 1) I used a similar bowl with cling wrap. I decided that I would try to free the bowl from the PM since I was concerned that it would shrink making it hard to free. The PM was slightly pliable and I used a wet butter knife to lightly pry the edge of the glass bowl from the PM before it hardened entirely.
Though I would like to go for the gold, creating an exemplary piece of art, I'm being patient and using this time to study. PM is simple from one perspective and appears that it could get complex at the same time. For instance I have plans to incorporate small objects (twigs, metal. petals. grasses etc.) into the pulp and gesso, so I plan to create a series of experiments to see what works and what might not (at least at first - try, try again). For instance, I was nibbling on some pistachio nuts in the shell and rolled out a small flat sheet of PM and embedded some of the 1/2 shells to see how they stick or not as the PM dries. That gave me the idea to keep a little collection of such experiments as a reference file. Hopefully that might be an idea others might want to adopt (I truly want to contribute to others here, especially since I have quite a bit of advice myself).
I'm headed to the store to pick up the Glad product and will continue experimenting, learning and creating.
Thanx! You "rock"
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Thanks, people!
I forgot about paste wax. And I totally agree that if it's been working, don't mess with success.
"That gave me the idea to keep a little collection of such experiments as a reference file."
That is such a good idea! Memory is a funny thing, and often faulty. Nothing is as good as a 3D example that you can hold in your hand with some comments attached to it.
For a long time (many years ago), I held onto a small cat (supposed to be a leopard) where I had pressed small stones into the surface to represent the spots. After some period of time, all the stones fell out. I assume that the PM shrank as it dried, leaving the holes larger than the stones, and the simple adhesive wasn't enough to hold them. I kept it around to remind myself to embed objects deeply enough (often more than halfway) so the PM would hold the object like a jewelry stone setting. AND to keep the object in a container so I could retrieve the rejected 'spots' so they could be glued back into place. But when I looked at the small leopard in a different light, I realized that the holes could also be viewed as another form of spots. Or they could be filled with a colored PM pulp and sanded smooth.
I've discovered that sometimes some passage of time helps to ferment ideas, giving my brain time to rethink the original plan.
Sue
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As always, great info and reflections on the "PM Path".
I just Arnold Grummer's book 'Complete Guide To Paper Casting' and he mentions paste wax. He also notes that glycerin, non-stick vegetable spray (Pam) and silicon spray can be used as release agents. He notes that the petroleum (Vaseline) jelly should be diluted with mineral spirits (white spirits in the UK) but not the ratio.
As part of my "experiments", I plan on trying each of these on the same molds (glass, metal & plastic) to compare.
I did get the "Glad" cling wrap and found it superior to the generic store brand. I clings to the glass bowl I tried with the other brand and it conforms to its much better and it seems stronger, less likely to tear.
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Koko,
While experimenting, try one with no release. Because glass and metal (in addition to plastic) aren't porous you may not need releases for those either. If you're casting the outside, you'll still need a removal strategy -- ie, shims to create separate sections, or a cut it off with a razor knife, or embed string/wire and pull to create removal sections. Oh, and I'm assuming the surface is smooth. If the surface has some texture detail, or any undercuts -- you'll likely need a release agent.
Glad the glad press and seal works. : )
-- b
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On petroleum jelly as a release agent:
I've just taken to using jelly when laminating over a positive mold with strips; after releasing, the part is cleaned with acetone- and will then welcome glue or pigment without issue. Only use acetone with gasketted eye protection, gloves, and ventilation.
Coloured jelly aids in removal.
---
I've also moistened the mold to receive powdered marble dust; the appropriatness of this technique is totally dependent on mold/model material and how the paper is applied (rough application may disturb the release).
-Christopher
Last edited by mavigogun (2012-11-26 21:11:37)
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Christopher,
I principally have used cling wrap as a release and pulp as my material on hard molds. I did try jelly twice and got mixed results with one mold releasing OK and another project where I had to cut the PM off. I know that its suggested that jelly be applied with only a light coat on your mold, but what constitutes light? I wonder if that was a factor in my failure. Even with that, I intend to try jelly as a release agent again in the future and any suggestions are welcomed.
You mention colored jelly, but I am only aware of petroleum jelly that is an off white, slightly yellow version. What is it bout the colored jelly that is better/different and why do you prefer it?
Is the acetone used to remove any residual jelly from your project? I assume that you dip and wipe the PM and the acetone evaporates the residue.
Can you explain (or point to a source) of how you use marble dust in your PM? I assume that the dust is either commercially available or perhaps from a shop that cuts stone (i.e. counters, tiles, tabletops etc.)
Thanx - Irv
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'Round here (Turkey), 'rose water' is commonly associated with medicine- and petroleum jelly may be had with a dark pink colour. The colouring aids in checking release coverage before molding, cleaning after, and serves as warning when excessive jelly collects after being displaced by mache- the colour polluting the glue.
Cleaning, acetone is applied with a tooth brush, wiped off with tissue. Don't use your regular brush- I favour my spouse's. 
Marble dust or calcium carbonate is a commonly used to augment soil for cultivation, and can be had from sculpting/casting material distributors, or on the cheep from gardening/farming suppliers. Don't confuse it with diatomaceous earth- which poses a lung hazard. I use it for stability/shrinkage control, to impart a porcelain like finish, and as a release agent in flexible molds.
My use of calcium carbonate and stippling developed from a struggle to retain detail from molds; I failed a lot. With that in mind, don't limit yourself to what others are satisfied with. When reviewing recipes for pulp, I oft wonder why one ingredient is favoured over another- or what impact to what part of the process results from the presence or absence. Like much of what we do, successful technique is a nuance thing- when and how much can't really be separated from context. Education only goes so far- experimenting is essential. Ever wondered what alum might do to pulp? I wish you would- it might save me material development time!
Last edited by mavigogun (2012-11-27 09:00:18)
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Calcium carbonate is called whiting or chalk in the US and Britain.
I've always wondered what effect alum was supposed to have, since you're only supposed to add a spoonful, So I broke down and looked it up: it's antibacterial, is included in the pickling of foods as a preservative, it's acidic (a negative in PM), a flame retardant, and as a whitener under some conditions.
Another use may prove it to be useful for papermaking: "Alum is used to clarify water by neutralizing the electrical double layer surrounding very fine suspended particles, allowing them to flocculate (stick together). After flocculation, the particles will be large enough to settle and can be removed."
When you do add extra ingredients, it's best to know why you're adding it and what the effect is likely to be. Don't just add it to be adding something. Keep in mind that some ingredients could affect the surface treatments.
Simplify, don't complicate.
Sue
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After reading a few patents, I wondered about what seemed, in my ignorance, extraneous ingredients. What is that doing in the clay? Some recipes favour tradition over relative benefit- no surprise that, considering that many ingredients require comprehensive apprehension of chemistry to judge contribution. Others don't. Take talc as an example of the later. From my ingredients notebook:
Talc: Mg3Si4O10(OH)2; soft, organophilic, hydrophobic
Talc is reputed to be the softest of minerals; its stratified platelets dislodge easily, imparting a soft, slippery feel- and, more importantly, fill minor voids. Water insoluble; partly soluble in dilute mineral acids. Naturally occurring as soapstone with related colouring.
Talc-carbonate: ore bodies are mainly composed of talc carbonate and traces of chlorite. Carbonate is typically magnesite (magnesium carbonate) or dolomite (magnesium and calcium carbonate).
Talc-chlorite: ore bodies consist mainly of talc (sometimes 100%) and chlorite, which is hydrated magnesium and aluminium silicate. Chlorite is lamellar, soft and organophilic like talc. However, it is more hydrophylic.
In a clay body:
may react as a cement
contribute to water resistance
fill minor voids
absorb excess of moisture from clay body, generally or from isolated pockets
changes general character of moist clay
Content in clay formulas:
Skratch, no more than 10% of non-paper portion (cement/clay/minerals)
References:
http://en.wikipedia.org/wiki/Talc
http://geology.com/minerals/talc.shtml
http://www.ima-na.org/talc
http://www.google.com/patents?id=-MrHAA … mp;f=false
Last edited by mavigogun (2012-11-28 05:36:19)
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Koko, getting back to one of your questions that I overlooked:
"Should my measurements be in dry or wet ounces? That might have been the issue of too much glue causing the above."
Jonni's recipe is all in cups and tablespoons, using volume, just like cooking. Don't try to complicate it. Use regular kitchen measuring utensils (preferably reserved for PM purposes). When you're going to measure out something sticky, like the joint compound or the Elmer's Glue-all, you can smear a tiny bit of oil inside the measuring cup so the contents doesn't stick to the inside.
How did the bowls you were working on turn out?
Sue
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That is a great tip about the oil Cat! I use linseed oil in my recipe, and I never measure it. I simply swirl it around my cups and spoons before I measure my other ingredients. I gt a small amount added and keep my instruments from getting sticky. To be honest, I don't measure much anymore. I use my measuring devices for scoops LOL. Most of my stuff is eyeballed and squish tested. Not very scientific I know 
Joey
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Joey, when it's new you use measurements, when you know what you're doing and what to expect, you can go by eye and 'feel'. It's called 'experience', a good thing. But there is a gap between the first and the second, isn't there? *laughs*
Sue
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(hand smacks head) Oil in the measuring cups! That's wonderful. I admit to having dedicated measuring cups/scoops for joint compound, that I wipe out with a paper towel, and then periodically have to chip out the rest. *Sheesh*
Mavio ... when you refer to stippling, are you referring to a technique you use with the marble dust / calcium carb? Do you pounce it with a brush (which is what I think of stippling as) ... or are you creating a texture on your finished piece?
I'm curious, you've got my mind whirling. : )
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CatPerson wrote:
Joey, when it's new you use measurements, when you know what you're doing and what to expect, you can go by eye and 'feel'.
I cast a series of rods to measure the impact of water content on shrinkage, strength, and density; significant differences were afforded within a granularity smaller than my ability to perceive reliably by feel.
The need to measure seems to me dependent on the application- what qualities are critical, and quantity. As with chemistry such as cooking, great things may be had intuitively and by precise measurement- or, often as not, with both.
I ain't contesting the Cat just to be contrary: sometimes results depend on very minor differences. If outcomes seem capricious, it may be time to break out the scale and measures. Just say'n.
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bmaskmaker wrote:
... when you refer to stippling, are you referring to a technique you use with the marble dust / calcium carb? Do you pounce it with a brush (which is what I think of stippling as) ... or are you creating a texture on your finished piece?
Marble dust may be pounced on, but only if the surface is no more than tacky- otherwise, the brush loads with binder instead of depositing dust.
Unlike Nives, I don't apply the tissue wet; I use the stippling brush primarily to set a single ply of dry tissue, and a separate brush to apply binder, layering. Binder, tissue; still damp? another layer of tissue; dry? more binder, then follow with more stippled in tissue. My binder is a mix of PVA, H2O, and marble dust for the first few layers. Nives wets out a glassy work surface with 3 parts methyl cellulose to 1 part PVA, lays in tissue, builds up several layers, wetting as necessary with fresh binder, and lifts off and applies the wet tissue with knives/razors/spatula.
An aside: I recently purchased Nives' PDF book to see what her technique offered; sadly, the book is bare bones, with only a single sparse paragraph on her use of tissue paper- and includes no nuance. If anybody wants it for half price, it's yours!
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"If outcomes seem capricious, it may be time to break out the scale and measures."
Of course!
It's like cooking. I don't use measurements for meat loaf, but I do for cake. Some you can play by ear, some you can't. But when you're making something for the first time, it's usually best to follow directions. Then you gradually learn what you can get away with, and what you can't. The hot pepper flakes that I used in the last meat loaf wouldn't have worked too well in the cake, I don't think.
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CatPerson wrote:
The hot pepper flakes that I used in the last meat loaf wouldn't have worked too well in the cake, I don't think.
LOL Depends on where your from! Besides, after watching some of these "master cooking" reality shows, I don't think any combination of ingredients is off limits as long as it looks pretty on the plate.
I agree that recipes should be followed closely at the beginning, and honestly they do allow for a more consistent mix. I have had trouble at times when I need a bit more clay to finish a product or make a patch and had a hard time getting the new clay to blend with the original.
Try as I may I can't keep my measurement precise. I start out measuring and leveling, then add another odd handful of this or a dollop of that to make it feel right, so all my efforts at precision are usually lost. 
Mav
I am fascinated by your tissue/chalk technique. I haven't played with tissue much but would love to experiment. If I should know this, I apologize, but do you have a gallery here so that i could see examples of your technique? It's always hard for me to match up the 'handles' used here on the board to names used in the gallery.
Joey
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kokopellime wrote:
* Using Jonni Good’s paper clay recipe, the pulp proved to be too sticky, maybe due to too much glue. What could be done to remedy such a situation? Do I add more paper, flour or dry wall mud, and is there a risk in offsetting the ratios of the mixture that could result in a finished project crumbling, cracking or some other horror?
* I would wet my hands from time to time as I molded my bowls which handled some of the stickiness. I'm concerned (not to much since it was so little water) that I could affect the recipe's ratios with the added moisture. Could I have done so and what could be the result?
Rereading your post, I can understand you frustration. I tried Jonni' recipe, and while I adore her results, I could never get past to the stickiness myself. I always ended up adding more calcium carbonate to remove it. I work with a very very dry mixture, and the drywall compound has too much moisture for my preference. I keep 3 small bowls on the bench next to me as I sculpt,One with just water, one with PVA and one with a soupy mixture of clay and glue. I dip my tools, usually a spoon or small sculpting tools, in one or the other to fill in or smooth as needed.
To me it's easier to add moisture than try to remove it.
I don't know if it is due to variances in brands or types of joint compound, or just my own habit, but it never had the right feel to me.
Joey
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paper soup wrote:
Mav
I am fascinated by your tissue/chalk technique. I haven't played with tissue much but would love to experiment. If I should know this, I apologize, but do you have a gallery here so that i could see examples of your technique? It's always hard for me to match up the 'handles' used here on the board to names used in the gallery.
No gallery, haven't posted work- much in progress, though. I'll share when complete.
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CatPerson
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It's hard to believe that you could mix gelatin, glucose (sugar), glycerin and a bit of alcohol and get a kind of rubber. And the rubber, while moderately flexible, is very tough. I've tried and I can't tear it. And it's reusable by melting!
Sue
I tried this mold material and it is quite good, although it is sensitive to heat. In fact, you can melt it down and re-use and reform it. It feels like a very dense, foamy rubber, flexible, but quite sturdy. I tried to tear a simple mold and couldn't do it. It appears infinitely reusable.
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rahul12 wrote:
It's hard to believe that you could mix gelatin, glucose (sugar), glycerin and a bit of alcohol and get a kind of rubber. And the rubber, while moderately flexible, is very tough. I've tried and I can't tear it. And it's reusable by melting!
Sue
Nice idea, i had been searching for a solution to my problem with mold for a few days now, and this is by far the best solution i've come across yet
Just thought id say thanks anyway, since i can get back to my project now
Sarah
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