Hi, I have been using kraft paper for all my large pieces(check out my gallery) .I find it can enable less layers,and it shrinks when dry which is good for flatning out,and the last coat is plain white newsprint paper to give painting surface. you are very lucky  from my angle, the mateial is purfect for large dramatic pieces

I have never used kraft paper for pulping, but it certainly is ideal for strip layering.  It is a strong paper, and appears to be the material of choice for commercial papier mache (PM) forms, the ready-made bases that are sold in the large craft chains here.  I have never seen pulp made from it.

The best way to use it would probably be to tear strips, lay them in a container, then pour water over them until they are wet.  They don't need to be anything more than wet.

Commercial low-tech operations use plaster, carved wood, or clay (air-dried or low-fired) as a form to wrap the PM over. Most people think of molds as interior molds, where the casting material is poured into the mold.  Papier mache molds are forms are that are made in the form you want them, although they may be simplified in design.

For a commercial operation of the type you indicate, having the people make an entire piece from scratch is not time- or cost-effective. Molds and forms are the only way to go.

For instance, a 30cm representation of a crouching rabbit could be made, possibly excluding features that would be better (and more easily) applied afterwards. A groove is scored along its back, down the center of its face, down its throat, belly and meets the original starting point on the back.

With practice, more complicated molds could be made, that are separated into more than two pieces, for ease of removal from the mold.

An appropriate number of layers for the project are applied and the object is left to dry.  Once dry, the PM form is slit with a blade, following the groove in the mold. Separated, the mold is removed and the two halves are joined together with more paper strips. 

Many 3-dimensional shapes can be used as molds with this method, and the first that comes to mind are narrow-necked jars. Any of these that included handles in the design should be built in, not merely attached.

Small, more delicate shapes can be attached with a good-quality glue. Ears, some tails, and other finer details would be included here.

Once fully dry (damp PM will mold, even under paint or sealer), the object should be sanded if necessary, then sealed with some sort of primer coat, to prevent any decorative painting from bleeding randomly into the paper. The primer coat will also help to avoid insect attack, esp if you are using a flour-based adhesive.

Most paints should be suitable, although acrylic and latex types dry faster than oil-based ones, helping to eliminate getting insects and wind-blown debris stuck to them.

All exposed surfaces should be sealed:  the interiors of jars, both sides of masks, etc.  While the interiors of jars needn't be decorated, they should be sealed against moisture and insect attack.

I haven't been involved in mass-production of this sort of thing, but I do have some suggestions.

1. Figure out the whole process yourself, from mold to PM to priming to paint to sealing. Write it down so you don't forget.  Make samples of every stage of the work. Nothing gets the message across like handing someone the piece and saying, "Do it so it looks like this".

2.  If possible, make an attempt to keep the different stages of manufacture at least somewhat separate: applying the paper strips, drying, painting, sealing, finished.  This should help prevent damage during the various stages, such as slopping adhesive on sanded or painted surfaces.

3. Emphasize the importance of firmly smoothing down the layers of paper to prevent or reduce lumps and ridges. Smaller curves require smaller or narrow pieces of paper, as pieces that are too large will create folds to allow for the extra material.

4. Sanding is the most time-consuming and laborious part of PM. The more folds/ridges/lumps on the piece, the more sanding will be required.

5. Make copies of your molds.  This way, you could have duplicates for use, and not have a money-making design lost if a single mold  was broken.  If low-fire clay is more available than plaster, you might be able to make duplicate clay castings from clay molds. Talk to your local potters, as clay is trickier than plaster, as it shrinks when it dries.

6. Encourage the people to come up with original designs.  If they could come up with original clay or wood designs, these designs could be multiplied using interior mold castings.  Seeing their own designs selling can create a stronger bond to the operation.

7. Don't limit their finishing creativity unless it's required. Some people who have never held a paintbrush have come up with extremely striking designs, but much of it evolves through mental fermentation. Design tends to evolve, so LET IT. Small cash prizes might be a good incentive for superior designs, maybe one each month for a new mold design, and one for a painted design.

8. This is papier mache, not the finest grade porcelain. Allow mistakes.  If you could find a good type of primer, bad paint jobs might just be wiped out with it, and they can start again. A white primer coat (whatever the material) produces the clearest colors.

* The advantage with plaster over clay for making molds is that it doesn't shrink like clay does when dries. But you might be able to coat a design (use a mold release of some type) with a thick layer of clay (each half separately). Let the clay dry, and remove the form, let dry until it can be fired, then fire it.

For designs, it might be feasible to stir up a batch of homemade oil-based clay. It can be reformed indefinitely, and it can be used to make molds from (digging or peeling out the clay after the mold is set or dry).  ALL OIL-BASED CLAY RECIPES REQUIRE HEAT AND OIL OR WAX, AND IT IS FLAMMABLE. Making it requires low heat and constant attention.  Don't give the job to someone who doesn't understand the dangers, or who will walk off and leave it.

Making your own oil-based clay (about 2/3 down the page):
http://users.lmi.net/drewid/oilclay_faq.html

If you don't know about UNDERCUTS, read up on them so you  can avoid them. Undercuts will trap a casting in a mold, and you'll have to destroy the mold to get it out.

If your idea works out, we would love to hear about it.  Good luck!

Sue

Lisa, I just noticed that you are in Mombasa. I am assuming that the humidity is high there.  I have spent very little time in high-heat, high-humidity places, but you might have a problem drying the pieces thoroughly.  A simple solar drying oven might be of help.  Once the piece has mostly dried, it could be put in the solar oven and dried more thoroughly, then the primer applied immediately, before the paper absorbs more moisture from the air.

Here is a site that has multiple designs for solar ovens, mainly for drying wet firewood, but drying is drying, whether it is wood, fruit or papier mache: http://www.woodweb.com/knowledge_base/S … gns_4.html

I think a design similar to #23 or #29 might be suitable, although I   don't think the fans and some of the other things are necessary for your purposes.

All you need is a simple box (walk-in size for what you are attempting) with a window pointed at the sun, and holes for air movement.  You will be using the principle of thermal convection, which is simple and free.

For instance, a large scrounged wooden shipping container would probably do very nicely.  Remove one long side wall (or most of it) and replace it with plastic or recycled windows.  Aim the window toward the sun.

You will need air intake vents low on the long wooden side, and air exhaust vents high (near the top) on the window side.  The air will come in through the low vents, be heated by the sun coming through the window, and automatically rise and vent through the holes near the top.  As the air passes over the PM pieces, it will carry off moisture. Just make sure that your top vents on still on the vertical side, not actually on the top -- you don't want to collect rainfall.

If you happened to have access to a solar-powered fan, it could be installed near the ceiling. If you had removed the whole sidewall for the window, the fan could be installed on one of the end walls, near the front window.  You want the air to cross the box, so you wouldn't want to install the exhaust fan on the same side as the intake vents.

Too-fast drying of papier mache can cause the pieces to warp when drying, so you'll want to experiment with how soon you can put the pieces in the solar dryer.  Should they be left on shelves in the workroom until they're nearly dry, and then transferred to the solar dryer?  Is the solar dryer 'cool' enough to put the wet PM in the dryer right from the beginning?  You'll have to experiment and see.

But I can't stress enough that the PM absolutely MUST be dry before it is primered and sealed. Mold will grow inside the PM and eventually it will discolor the paint or finish.

Keep track of which designs sell best, and which don't.  Drop the ones that don't, or revise them somehow.  If you're selling locally, keep an ear out for people who ask for certain things, which could be new things to design and sell.  Keep notes.

There are matte finishes and glossy finishes, and which you use them on will vary.  All glossy is often not appropriate.

And if you're selling to tourists, PM representations of African animals and masks could be big sellers if nicely done. If possible, you might want to consider offering shipping their purchases (include shipping costs, packing materials and labor), and be sure they are packaged properly. Even rubbing in transit can abrade part of the finish.

Please let us know if this all works out.

Sue

Here is the leaf photo. They have more character in person . . . .

Office paper is a hard, hot-pressed paper.  It makes a stiffer, firmer form than the softer papers like paper towels or newspaper.  I think kraft paper is similar to the office paper, just not bleached into whiteness.  One thing to consider is using the kraft paper for the main body of the pieces, and if you have access to office paper, apply that as the final layer(s).  If you have a problem being able to tell where one layer ends and the next begins, adding a light tint of paint or something to the glue may help:  complete layer (plain), then the next with the color, the next plain, the next with color. A spoonful of tempera in your glue may be enough. It just needs to be enough to see.

Glue -- are you trying the rather thick 'plastic' types of glues, like the white PVA craft glue (aka polyvinyl acetate) and the yellow PVA wood glues?

Try this for your moisture problem:  Dilute the glue half and half with water.  Don't soak the paper at all.  Brush the glue onto one side of the paper and apply to the project, smooth firmly in place. Repeat.  Thinner glue, drier paper? 

The main thing to remember here would be sizing the pieces or strips of paper to the curves of the piece to reduce/eliminate wrinkles.  This alone is going to make a big difference in the final surface, and how much sanding it will need (the less, the better).

"How can we tell that something is REALLY dry through and through?"

I can usually tell best by feeling:  a combination of temperature and weight.  A dry piece is light and warmer; a damp piece is heavier and cooler.  Developing an 'ear' for how it sounds when you tap it may also prove useful, esp if you use the same materials all the time.

If you're using plastic as a form, try it without any mold release whatsoever, even without plastic film.  Plastic items tend to be 'special' in that respect. Most PM will release from plastic when it is dry or mostly dry, especially when the paper in inside a curve (like a bowl).  PM shrinks when it dries, and tends to pull loose from the plastic mold.  Try it and see if it works with the plastics you're using.  This does NOT apply to any other form material -- it sticks to everything else.

If you use a mold release like Vasoline (or anything else), you will usually only need a thin film of it.  Try the plain paper method I mentioned above, if it seems appropriate.  You can even use wet/damp paper so it will stick to the form, and then start applying paper with glue on top of that first plain layer.  It won't work for everything, though.

Your pendent idea sounds good.  Maybe you could have some clay molds made, using actual leaves.  The ones with the most texture might be the most useful, and maybe making the veins deeper in the molds would produce a more appealing piece.  If it's easier to make the PM leaves on protruding veins, maybe your moldmaker could make a mold of the mold: Impress a leaf onto clay, then make the veins deeper manually; fire the mold, then make another mold from THAT mold, and you would have a positive mold to make a negative impression.

If you want really flat pieces for pendants, you'll probably need some kind of pressure to keep them flat while they dry. This may take some experimentation.  If you have any experience in papermaking, some of those techniques may help.  Otherwise, layering and gluing (maybe with no glue on the outside of the layers), then set a bunch of them on a mat of newspapers, cover with more newspapers, lay a board on top, and weight with anything heavy, even rocks or bricks.

Another idea for jewelry might be shallow clay molds -- press the paper into the mold and produce a rounded form (oval, elipse, heart, etc).

Sue

For leaves and jewelry, light dabs and brushes of gold or silver paint adds a really nice effect.

Thanks Sue and David for your additional suggestions. I haven't checked the forum for a while because we have been making papier mache! I had begun to wonder about adding some sort of colour to the glue to keep track of the layers, good idea. Also glad for the tip about release from plastic molds, will give that a try right away as I find the Vaseline really annoying, perhaps because of the high temperature here. it just seems to get all over everything and soaks right into the paper. And I will try the thinned glue to see what difference that makes to our drying times. The air is practically liquid here at the moment, though it is less humid at some parts of the year. I did try the layer of wet, plain paper first to aid with release but found that it peeled off in sheets and spoiled the shapes in most cases.

We've been experimenting with different thicknesses for vessels and small trays. I've noticed that some of the pieces have a spongy feel even when dry. Not all turn out this way. Some are very solid, practically like wood reconstituted. What are we doing/not doing to produce the sponges? We have been trying different brands of glue and parquet adhesive vs. regular wood glue but the sponginess doesn't seem to relate to the glue.

We've tried a few larger trays but I find that these pieces curve upward at the center as they dry, so the bottom of the tray is not flat. Any suggestions here?

We have not had a chance to build a solar drier yet but that seems to be a must for a project like this.

Will have a go with the other suggestions on the pendants.

I read with interest another post about cloth mache. Another of our projects leaves us with a lot of fabric scraps that I would like to incorporate into the pieces as decoration. Can we just treat these like the paper strips for the final layer? Any suggestions about how to apply glue to cloth with the least mess or how to deal with fraying. I will send off for the book you recommended on this subject eventually but am eager to experiment a little now.

Thanks again for all the great support!

Lisa

The first plain layer of paper (with no adhesive) should not be peeling off. When the next layer of paper (with adhesive) is applied, it should be sticking to the plain paper.  This problem and the sponginess makes me wonder of if the paper is not being pressed down firmly. There must be good contact. Air between the layers, and layers coming apart tend to be signs of poor contact.  Make sure that everyone understands that the layers must be pressed firmly and smoothly together.

The trays curving upward in the center:  This may be due to  uneven drying. The solution may be as simple as pressing down on the pieces firmly several times a day with a flat board, 'reminding' it to lay flat. 

If you do have access to several (or many) flat boards (untreated, just raw wood), you may find it necessary when the trays are partly dry, to lay a board on each one, press it down, and weight it for a day.  Then turn the board over and repeat.  The board should be absorbing a small amount of moisture from the PM (helping it dry), and flipping it over should produce a new drier (relatively) surface, and the weight should be keeping it flat.  This is a problem even with laminated plywood -- when one side is glued or painted, it warps into a curve.  With PM, esp when you're working on a plastic form, the side exposed to the air dries more quickly than the side against the plastic.  On the trays, it may help when the pieces are partly dry, to remove them from the plastic form and weight them down.

If you are wanting to use the fabric as a decoupage decoration, try a small piece 30x30cm:  lay it face down on a flat surface and paint or roller a clear adhesive all over the back, and let dry thoroughly.  Then use scissors to cut out appropriate shapes.  Now glue the pieces to a PM surface (an imperfect or damaged piece is fine), and when that is thoroughly dry, cover with a sealer. The application of the adhesive should curb the fraying.

Warning:  you've probably already thought of this, but since *I* have been known to overlook the totally obvious.... Don't try to use too many different types of adhesives.  Do your experimenting, then settle down to the best for your particular purposes.  If there are some things that require something different, make sure that everyone understands that those adhesives are to be used just for named items, that the adhesives are not interchangeable.

Using too many types of adhesives can cause problems due to conflict of chemicals (not drying completely, staying sticky, etc), or layers coming apart (delaminating) due to chemical reactions. Some of these last may not be obvious for some time. 

One example is when certain types of adhesives are used with certain types of plastics.  At first, it looks fine, but then the two dissimilar products eventually react with each other, and they separate.  NOT good advertising!

Specifically, what is the parquet floor adhesive that you are using?  If it is a type I've seen, it may be a source of trouble if it is the type that is rubbery when dry. If you're not sure, drop a spoonful onto cling film and let it dry. Does it flex or feel spongy?

Sue