(and can i say how sore my hands are from pushing that clay through?)
There are various ways to keep that from happening that you should check out (I have problems with my hands/arms so I've had to use some of them).
The cheapest and easiest solution IMO is to make a wood "bellows" pusher for the gun by screwing a hinge to 2 boards, then putting a hole in one board (little larger than the cap on the clay gun). That allows me to squirt out a barrelful (about 12") of (properly prepared) Premo for example, in 2-3 seconds. Here's a photo:
There's a lesson on making one of these on the Clay Guns page of my site -- as well as ways to make the clay softer for extruding, and also other kinds of helpers and clay guns which can make the extruding easier: http://www.glassattic.com/polymer/claygun.htm (... for the bellows pusher, click on Bellows... for other things, check the rest of the category list)
(Mine too... actually, I have several, all cheapies.)
.. . I would spend the next hour or so with my long sewing needles scraping it off of sides. >smacking my head<, why didn't I think of paper?
LOL... you're in good company. Most clayers are still doing some version of that (...or rather they end up not using their clay guns because cleaning them between colors is just too much trouble). I only came up with the paper method out of sheer desperation... I was due to give a clay gun class to my guild and felt like cleaning would be a real sticking point (no pun intended) that would end up keeping them from trying all the neat things I hoped to show. I'd also tried just about every way imaginable myself to clean them out more easily, but none were nearly good enough. So I did a lot of experimenting and trying things till I happened on a good combination. (Do read the instructions for the "clean barrel extruding" though on my site because there are some details about length, revolutions, types of paper, etc., that can be important.) Maybe I'll go upload a photo of the basic technique, then post it here. ....okay, here's one shot (ooh, that's big):
Btw, the one time you shouldn't use the paper method or a some similar method is when you want the clay to drag on the sides of the barrel, as with the "automatically wrapped canes" technique for making what I call "dot slice" canes, etc.
I seen other clayers on tv rig some wood scraps with barrel hole and hinges, so that more leverage is used to extrude. I like using the stiffer Kato clays for quilt caning. . . . I use my wood tv tray for leverage, and have nicks in it from the handle of clay gun. I keep one hand around barrel to keep clay warm as I push..
The "bellows" type of clay gun helper or "pusher" is another things I came to out of desperation. I had seen the original wood bellows pusher (2 boards hinged together, one with a hole in it) that was sold by WeeFolks, but so many people reported that it bent their guns or stripped off the paint that I never got one. However, I have problems with my hands/arms/chest so eventually I HAD to have something that would help. My DH is a physicist, so I asked him about modifying the bellows type or if we could think of something else that would work*. He said there was no reason the bellows shouldn't work, but when he saw the photo of theirs, he said that just a few changes would avoid the problems that people had been having (moving the hole to the other end of the board, and making sure it was a little larger). We made one, and it worked like a charm... I can extrude a barrelful of properly warmed Premo, for example, in 2-3 seconds with it YAY!
I have some photos of that original one here (until Yahoophotos goes belly-up anyway) showing the clay I've extruded with it in that one push -- actually there's one photo at least at Photobucket, so here it is:
I also wrote up a lesson on how to make them on my Clay Guns page which a lot of people have found useful. (I ended up making about 15 of them to sell just for cost at that clay gun class... for those later ones, we decided to make the boards a tad longer for even more torque.)
There are also hints on that page about how to prepare the clay (and the clay gun) so that the clay is soft enough to extrude, if you haven't read that already.
*lots of clayer were using a caulking gun with some extra bits added to hold the clay gun in the cauling gun, but that whole apparatus is too big for me to have sitting around handy, and it would still be too hard on my fingers and hands... all I have to do with mine is lean on it, and my whole body acts like a pusher ... other clay gun "helpers" have been created too, but they mostly have one disadvantage or another ... many require the gun to be removed from the helper for every refill (no thanks), or are much more expensive, etc.
Well, I helped my son do a clay brain for one of his projects (maybe bigger than what you need), and it wasn't easy. It certainly wasn't easy to figure out how to do it well, and accurately, and also wasn't easy to make it. His ended up with the brain stem parts removable as a unit, but no other parts were removable... it was one hemisphere only btw, with the cross-section showing on one side. Here's a photo of that hemisphere from the outside:
In this next photo, the hemisphere was lying down (with the cross-section on the table... oh, and the removable brain stem wasn't in place for the shot, and the cerebellum hadn't been added to the cortex yet)
OOPS... just reread your message and see that only the lobes needed to be removable. That would be considerably easier! In that case you could make the cross-section actually flat (like the inner ear described below)... bake that, then add 3-dimensional lobes for the one hemisphere (maybe with scrunched aluminum foil armatures inside each to keep them from being thick enough to crack while baking) to the back side of the flat cross-section...separate each lobe from the other and from the cross-section with a tissue or a bit of ArmorAll to keep them from sticking together while baking. Guess you could hold them together after completion with velcro or wall-poster putty or something, which would allow them to be easily separated . .
So if you can avoid the removable-parts option, I would definitely do that! (if you decide on it anyway, I can give you some things to think about and some suggestions). You didn't say your age or the level of the class, so that could make a difference in how hard it would be re getting things more or less exact, or having fewer parts.
The easiest way would be to do it like a "puzzle-piece" painting or bas relief. For that you'd make a flat base of clay (maybe skin colored) in the shape of the final model you want. Then you'd make each anatomical part in a different clay color, and press each firmly onto the base clay. It would be helpful to lightly scribe a pattern on the clay to follow for placement... or you could do at least a pale "transfer" to the clay by firmly pressing a photocopy to the clay and leaving it for awhile before removing (remember to reverse image first, if you want it the original orientation on the clay) ...or you could just put the photocopy or drawing under a sheet of glass onto which you place the parts directly --no base clay--then bake on the clay and remove after cooling. For that last method, make sure all the parts are well connected to each other so they'll stay together when removed or handled.
After you do the basic puzzle-piece illustration and bake it probably, you could add clay to its back side if you wanted and baked again to give it some sort of 3-D shape. And/or you could make the middle ear just a bit thicker by adding a thick sheet of clay, then also make yourself an outer ear more like a sculpt to add to it, as in many of the ear illustrations.
There's more info on the basic puzzle-piece "painting" technique on this page, if you want to look at it: http://www.glassattic.com/polymer/paints.htm (... click on Bas Relief and/or Puzzle-Pieced, under "Polymer Paintings"...) (you'd be making your pieces thicker, and even slightly bas relief perhaps, but the basic technique would be the same)
And here's the brain my son and I did, mentioned before -- it's actually half a brain, one hemisphere; the photos are from each side but for the cortex shot, the removable brain stem and cerebellum piece was missing (...oooo, those images turned out BIG):
RecycleMicol, this is for you --to show some of the ways you could embed a needle or multiple needles into polymer clay if you wanted. (Sounds like buying those cheapest felting needles would be easier, but just wanted you to see these if you wanted to try.)
The tools in this first photo (gifts to me from Cecelia Determan) are double-ended, as well as being multipurpose.
The bottom tool has 3 needle tips embedded in a triangle shape very close together which is used as a furring tool like the one Katherine Dewey uses on the mice in her Sculpting Lifelike Animals book. It's dragged along the surface in short strokes.
At the other end, 20 or so straight pins (cut really short) are embedded randomly (end is 3/4" x 1.5") ...some pins have sharp points, and some have rougher points since they were cut with wire cutters. Can be dragged or pressed.
The top tool has a needle embedded in it which has had the top part of the eye cut off... it's used to embed bits of "hair" like mohair, etc., into a raw polymer clay head (for most realism).
Its other end is a circle made from wire, bent, then embedded, so that it can be used to impress multiple small circles on raw clay to simulate a curly beard or some kinds of fur or wool ... Cecelia wrote about these in her HOTP book Merry Christmas Faces; she wraps a 1 1/2" length of (20-gauge) wire around a bamboo skewer or pencil tip to form a 1/8" wide circle, bends both tails back to insert into a handle of clay, leaving a flat circle for stamping ...(or the circle end of a safety pin could be used)
The next ones are a few of the other things I've embedded in polymer handles for better grip and longer length.
These are single pins, ball-headed pins, and needles (including a tapestry needle):
And these last ones are a drill bit, a V-type linoleum cutter bit, and some "smile" tools for simple figures. The smile tools are made by bending down the U end of a paperclip, then cutting that off past the bend and embedding in clay.... when pressed onto a blank clay face, they make a cute smile indention (or a frown if upside down). (Yellow one shows tool from the side.) The last one on the left is one-legged and the same idea, but can also be used in other ways.
Some of these stay in best if they're pulled out after baking (sometimes pliers are necessary, but sometimes they can't be removed!), then glued back in with superglue. A few like some of the paperclips, are actually still whole, just covered with clay in the middle.
actually, if you choose what album you want them in from the drop down menu at the top of the widget, and then upload the pictures, they'll be in the correct album.
Thanks, Kiwimonkey! That makes a big difference... not sure how I missed that, but the order in which things need to be done are a little confusing.
So, for Craftster... it looks like the album (actually "sub-album" according to PB) must be selected first ...then Browse and select image ...then Upload Image.
Hmmm... I should try adding to PB a new image which I already have a suitable sub-album for, then put it here just to make sure it works for me:
Seems to work... yay!
Some of my problems are trying to figure out basic Photobucket at the same time as the widget here... for example, I don't seem to be able to easily add new sub-albums at PB --sometimes they show up, and sometimes they don't.
1. Can you tell me exactly what order things need to be done in to create a new sub-album at PB?
2. And does one need to put a photo into the new sub-album at the same time to be able to create a new sub-album, etc., also at PB?
The first set of color samples I posted a while back was made with only 3 colors (of Premo) by someone in my clay guild years ago: http://www.craftster.org/forum/index.php?topic=101494.0 Before that though, I had made some samples of my own color mixes from more colors, including fluorescents (primarily Premo, I think) to get familiar with what happens when polymer clays are mixed.
I also wanted to mark the chip samples somehow with their exact formulas so I could use them later when previewing a few colors together, etc., and be able to duplicate them, so I tried variuos methods. ....markers (permanent-on-plastic type), stamping into raw clay leaving impresions, "writing" in raw clay with pin or stylus, stamping after baking on surface with various inks ...I also cut some of the shapes with a wavy square cutter, and used a heart-shaped cutter for the hole, etc. I never really finished the whole project, but here's a close-up showing some of the marking systems I used:.
I recently decided to find them, then lay out in spectral "order" just to see what I had. (Note that these are all plain mixes though... with no white added to get "tints" (pink, peach, lavendar, etc.), and no black added for "shades," but a few "tones" did result just from mixing complementary colors (not by mixing in grey or brown though) ... also almost no mixes were made with mica-containing metallic clays, and none with translucents). The photos don't really show all the differences in color, of course, and some of the colors look kind of blotchy or something probably because of increasing the contrast.
closeup of chip colors ...yellow-orange-red end of the spectrum
closeup of chip colors ...red-magenta-purple-blue-turquoise-aqua-green-yellowgreen end of spectrum ....the five single colors bottom right are a random brown(?), silver, glow-in-the-dark, Sculpey III translucent, SuperSculpey (last two showing up a bit too pink though)
. Okay... I found some of the photos from that color exercise class. Here are most of the color choices laid out on the tables (there were a lot more "tones" there than really show up in the photo though):
This was one of my color palette choices (we were supposed to pick at least 5 colors... I hadn't decided which I'd want to remove when I took the photo but I thought I had too many)
Another of my palettes... I was obviously in a particular color mood that day!
These were made as magnets for my son's teacher's brand new white board (they'd used chalkboards previously).
Some of them had to do with the subjects they were studying that year or with things they had in the classroom (kids included... I modeled the brown haired one after my son). The background for the 3 faces was one of the old wonderful Fimo "faux stone" clay colors which are no longer sold.
Most magnets were all-polymer as I remember, sometimes adding the cane slices over a core of scrap clay... they had small magnets embedded their backs which were removed for baking, then glued back in with E6000 (now I'd probably use an epoxy glue though they're still working 9 years later according to the teacher --unless she doesn't want to tell me they aren't).
There are various polymer techniques represented in the items, especially: ... canes, "covering," simple sculpting, "aquarium bead" with fish & seaweed, transfers, discrete blends (from the days before "Skinner" blends), etc.
(each horizontal row shows the range of mixtures created by mixing the color in its left column with the color in its right column)
This sampler of polymer clay color chips was created by my guild to show just 4 simple combinations of colors that can be created by mixing only the 6 "primaries" of Premo with each other, two at a time (those are the colors the ends of each row).
Premo actually has a warm and cool version of each of their red, blue and yellow primaries (for a total of 6): ...Cobalt (warm blue)...Ultramarine (cool blue) ...Cadmium Red (warm red)... Alizarin Crimson (cool red) ...Cadmium Yellow (warm yellow)... Zinc Yellow (cool yellow) (Most other brands have only one version of their purest version of red, blue, and yellow.)
A lot of the true color variations can't be seen from the photo (especially in the darker colors), but at least it gives a general idea of what can happen when just a few colors of clay are mixed!
Keep in mind though that only a few of the polymer colors that can be purchased were used for this sampler, so there could be many more simple combinations --including for example, each of these colors with a secondary color (turquoise, green, purple), etc., or even these colors with a metallic colored clay or with translucent clay.
Also, each of these colors (or any other clay color) could be further changed into many-many other colors by adding white (to create a series of "tints"), adding black (to create a series of "shades"), or adding gray, brown, or the complement of the color (to create a series of "tones"). The combinations possible are limited only by what the eye can discern and which colors one uses.... kinda overwhelming actually.
OTHER WAYS to create various colors of raw polymer clay yourself have to do with mixing other things besides clay into the clay (...usually white or translucent clay is used as the base).
The two main colorants are oil paints and alcohol inks like Pinata and Ranger (for inks, apply to clay sheet, then let alcohol evaporate off before mixing color in). You can use acrylic paints too, but since those contain water (which can expand during heating and cause bubbles, etc.), you wouldn't want to use much acrylic paint in a specific bit of raw clay (...or just leave the colored clay out overnight before baking to let most of the water evaporate out of the clay).
Many other colorants can be used to give a solid color or a speckled color, to the body of raw clay: ...ground spices, dry pigments, and dry tempera, fabric dyes, concentrated tea, crayon shavings, and metallic powders... as well as embossing powders, play sands, some glitters, herbs, even dirt, etc. (those are generally mixed into translucent clay, or into translucents which have been tinted with color, so they'll show up some distance "into" the clay after baking as well as on the surface ...then they're often called "inclusions", and some inclusions in translucent clay can look especially amazing if they're sanded and buffed or given a glossy sealer too).
LESSONS & RECIPES for mixing whole palettes of color (from just a 3 primaries plus black and white) as well as mixing many interesting individual colors can be found on the page linked to at top.