Getting Started in Wax

[Indigo]

Hi!

I've recently been given a whole load of casting supplies, Resin, silicone, vacuum, etc. And what I really want to do now is move towards wax carving/sculpting, and casting. I make figurines from a few inches to sometimes 15 inches or more. I've been researching different kinds of wax, and have found that the microcrystalline wax is the kind often used for my purposes.
I have a 1lb block of amaco carving wax, but online I have seen the option to buy large packs of microcrystalline wax for just 1.50/lb. Is there something different in the way these waxes are made? is the more pricier (amaco) wax just more highly refined?

Also, I'm rather clueless about the whole process. I had originally planned to melt my wax and cast it into a cylindrical shape, and then just carve away like it was a block of wood. However, after reading through the forums, I have seen that armature is required for some of the larger pieces. As far as armature is concerned, would I place a metal skeleton into the cylindrical wax cast, or somehow apply the wax to to the armature in a greater amount than needed, and then carve away the excess?

Sorry for all the questions and my obvious cluelessness when it comes to this medium! I'd really appriciate it if anyone could reccomend any books or websites which detail figurative wax sculpting.

Thanks in advance!

Indigo

[fritchie]

Indigo - Here are a few facts or opinions, hopefully somewhat educated. Microcrystalline wax is a generic term for wax that tends to form in very small particles, and is a nearly smooth, continuous material when it solidifies. It comes in all colors from white (candle wax) through various browns and nearly pure black. For sculpture, you want a hard, high-melting variety, and color is more or less immaterial.

Smallish sculpture (up to say, 15 inches in max dimension) probably won’t require an armature in reasonablely cool locations, but if you feel the sculpture needs strengthening, small pieces of wood or bamboo, such as ice-cream or barbeque sticks, can be inserted and built upon. They will burn with the wax when a cast is made.

Larger sculptures also go through a wax stage. The original typically is formed in a clay of some sort, and then a mold is made and filled with wax. The wax is encased in a plaster-like material; the wax is melted out, and bronze, aluminum, or other material is poured into the hollows of the mold. This is the “lost wax process”.

Hope this gets you started!

[Jamo]

Here are a few tips I have learned from wax. Keeping a light pointed on a block of wax at a medium setting will turn it into a modelling consistency that is malleable. You can model it only so far until it cools. After that you can use a blow torch or heat gun to soften it again. For small figures I wouldn't use armature. For smaller figures I would set them firmly on a rigid surface so that you can avoid handling it. I find the warmth of your hands will significantly deform the wax through handling. The rigid surface allows you to manipulate the piece without causing any malformations to it. getting into larger pieces you can use styfoam carved to a general shape then lay the wax on top of it in liquid form, built up with a paintbrush. For medium sized sculptures you can use metal armature keeping in mind that it does not burn like styrofoam. It may be a task to section it off into smaller pieces for mold making if it is a complicated piece. Make sure that on the armature there is something for the wax to grab onto so it doesnt slip a fall off the armature. Paraffin sucks dont use it. If you like carving wax is great. If you are a strict modeller then wax leaves something to be desired but is still manageable. Its a personal prefference thing.

[fritchie]

Jamo - I've wanted to say something about your making that large piece in wax since you first posted, but I didn’t get to it right away, and then it slipped into the background.

People in climates warmer than Newfoundland might want to be careful if they choose to sculpt directly in wax. What kind of wax is it that you use? I typically sculpt in oil-based clay, make a mold, cast the piece in a relatively hard, high-melting sculptural wax, clean that up and give the wax to a foundry for casting.

I usually transport the finished wax in a large plastic garbage can, wrapped in a smaller plastic garbage bag and surrounded with plastic-wrapped foam pads to cushion it for the journey. Despite my using a high-melting wax, here in the southern U. S., I find that the wax is easily deformed at any stage.

[Jamo]

thats a very good point. Us Newfies are used to shoveling snow in may and breaking out the shorts in 5 degree weather. Shipping wax/working with it in the summer can be a pure nightmare. In climates like florida you have to pretty much keep the wax in an air conditioned room in the shade. you wouldnt need a lamp to keep it malleable. Thats a tough one to deal with and requires special shipping needs where it is 25 degrees all the time. Unless you could arrange something with a shipping company in a controled temperature environment and while you are working the wax keep it in a cool area. I have no other ideas towards this. Its not a problem where I live. I use microcrystalline foundry blend or victory brown.

[Jamo]

Also, hollow cast waxes from molds dont have the benefit of having a combustable armature that usually limits deformation. The sculptor that I apprenticed from used to add bamboo sticks while casting the wax in the mold
supported with burlap. Both combustable materials and perfectly fine to use at a foundry for lost wax casting.

[fritchie]

Also, hollow cast waxes from molds dont have the benefit of having a combustable armature that usually limits deformation. The sculptor that I apprenticed from used to add bamboo sticks while casting the wax in the mold
supported with burlap. Both combustable materials and perfectly fine to use at a foundry for lost wax casting.

(From earlier post)...I use microcrystalline foundry blend or victory brown. ...

Are you saying he painted wax into parts of an open mold, and reinforced the wax with sticks, burlap and so on, then closed the mold and sealed the joints? I have used that painting technique on large molds, but never added internal agents as you describe.

As for “Victory Brown”, the local art departments use that, but I gave it up long ago as much too soft for this environment. My studio is air-conditioned, and so are the schools, but I still found it too sticky and messy.

[Jamo]

I'm not saying I would recommend it but that is what this one sculptor did. It does limit warping to some degree but wax unsupported by a complete structure still moves in mysterious ways. Also he wasn't using this added material in the sculpting stage but for foundry purposes afater the mold was taken. On that note wax with a styrofoam armature underneath doesn't move at all. If it is the same victory brown we are talking about I didn't find it sticky at all. maybe it's preferrence but I have found in the past that warm wax can be a pain to keep detail while handling.

[fritchie]

I'm not saying I would recommend it but that is what this one sculptor did. It does limit warping to some degree but wax unsupported by a complete structure still moves in mysterious ways. Also he wasn't using this added material in the sculpting stage but for foundry purposes afater the mold was taken. On that note wax with a styrofoam armature underneath doesn't move at all. If it is the same victory brown we are talking about I didn't find it sticky at all. maybe it's preferrence but I have found in the past that warm wax can be a pain to keep detail while handling.

I suspect we are talking about the same “victory brown” wax. When I first started, I did some Internet research, probably after becoming unhappy with this wax. I could be way off the mark, but my impression is that it was marketed under that name during World War II, and possibly earlier. I believe local sculptors said the same thing.

Certainly, it is a microcrystalline wax, and so are several others I tried before settling on my current one. I believe all of these are petroleum derivatives, just different “fractions” removed from a distillation process during refining, at different temperatures.

I also forgot to say that local sculptors may add up to ten percent paraffin, the normal white stuff used in food canning. Paraffin makes the mixture a bit harder and gives the surface a higher luster. More than ten percent is said to make it too brittle. I think paraffin also is considered microcrystalline, and that it simply is a very highly purified form of the same thing.

[grayem]

I beleive you can buy summer wax and winter wax from wax suppliers, like Remet.com
I saw a video of a foundry on a tropical island and they mxed red sprue wax with the brown to get a stiffer wax that wouldnt melt too fast. I ahve working the summer with what must have been winter wax outside in the sun, and it jsut didnt work. It was like silly putty after 2 hours.

[fritchie]

Yes, obviously direct experience with the wax you have is necessary. These waxes often are mixed by the sculptor, and until you try, you won’t know the properties.

You might buy a small amount of wax from a local sculpture supplier or art school, if you can, or ask them to look at a small sample of the wax you have, for comparison. Then you can get an idea of whether you need to mix a harder (higher-melting) wax with what you have, or try a harder wax overall. Just remember, always get microcrystalline wax. That can come from different sources, such as petroleum or bee honeycombss.

[Bford]

It this is the wrong forum for this, I apologize in advance...please advise if so. I am going to be up front - I work in the wax industry - I sell wax. Regarding Brown Micro wax - VB wax is longer being produced. We have formulated a very good replacement. I know this product has been a mainstay to sculptors for many years...and I want you to know someone is out there interested in keeping the tradition alive. In reverence to this post not becoming any more of a commerical, i am not listing my company name or products. Feel free to contact me directly with any questions or if i can be of assistance. Thank you for your time.

[sdg77]

indigo- hi! i am also just getting started in wax in a foundry class at my local university. i really hated the stuff at first- found it hard to work with- but i am learning- and i am really beginning to enjoy it. i use the victory brown wax.

i work the wax like clay- i keep a bucket of hot water to soften the wax and a bucket of cold water to freeze it when i get something i like. i also keep a hot plate to heat some basic tools and a cheap soldering iron. You could also use an alcohol lamp. The tools i use the most are my fingers and the skin is getting worn off in some places! :D i model the wax like clay, but once it is frozen i also can carve away at it.

i think you just need to play with it- it may be frustrating at first but keep at it!

also for stiffening the wax- my prof. recommends 1lb parafin to 10lb victory brown- and absolutely nor more than 2lbs per 10lbs.

hope this helps!

[F.C. White]

BFORD,

I would very much like to have more information in what you offer of a wax product. Thanks.

[BMBourgoyne]

I would strongly recommend this book:
Figure Sculpture in Wax and Plaster (Paperback)
by Richard McDermott Miller
ISBN: 0486253546
its about $10.00 at Amazon.com, as it is a old Dover book, but I've yet to see one better-- it is very straight forward and very useful for modeling wax sculpture.

good luck

[realsculpt]

check out" Ross wax" company in new jersey i dont know thier number but they make some great waxes, also darby dental, sells yellow bite wax, its what i use, you can also get "castaline" thats really cool stuff. i would get a crockpot, melt wax in it a tthe 200 degree setting or less, this can keep it liquid, then pour it in to bricks or plastic cups as it cools it can become pliable. Darby sells wax pens too, they are for dental and jewelry making, that are pricey though. you can also smooth wax with mineral spirits and a stencil brush. I know some withh get those cheap clipon spotlights, tape a metal pie pan to it and heat the wax with a low watt light bulb, to keep it pliable.

for figures, i know people in the toy industry sculpt un supersculpty, then mold it and then pour wax into it to do final details.

anyway hope that helps a bit.

[Bford]

Looking for a Victory Brown type wax? I am the manufacturer of this wax...if you need less than pallet quantities, I am happy to direct you to one of our distributors.

Test Description Test Method Min. Max. Typical
MELT POINT °F(°C) ASTM D-127 150 (65.6) 170 (76.7) 162 (72.2)
PENETRATION @ 77°F ASTM D-1321 20 35
PENETRATION @ 110°F ASTM D-1321 90 200
VISC @ 210°F (SUS) ASTM D-2161 70 100
COLOR ASTM D-1500 DARK BROWN

[dondougan]

Getting started in wax

Ancient waxes for lostwax casting were usually combinations of beeswax, crushed and sifted lump rosin, and charcoal dust for color - all materials mixed when the wax was at liquid.

Softer waxes have more beeswax, harder ones have more rosin. Softer waxes allow for greater ease in modelling work, harder waxes allow for greater ease in carving work. The color is to allow easier perception and modelling of form by reducing or eliminating the visual distortions caused by the natural translucency of the wax.

Commercially-prepared and colored waxes are much less trouble for the contemporary modeller/founder than compounding ancient wax formulas (I've tried it the old way), but knowing the methods can only help your understanding of the processes.

For working in non-air-conditioned Italian foundry studios the common means of dealing with Mediterranean summer heat and its effect on the wax model is to keep a tub of water (in a shaded area) in which the wax models are placed/stored between working sessions.

Anything combustible can be used in the lostwax process as either a form, texture, or as a reinforcing armature -- though the required time to burn-out the mold completely (usually about 24 hours at full burn-out temperature [550-degrees Centigrade] for a 100% wax model investment) will be increased with usage of anything in the model harder and denser than the wax itself. Bamboo skewers and toothpicks are commonly employed as reinforcing armatures, and thin enough that they will not increase the burnout time if used.

Blocks of expanded styrene foam can be used as a core for more massive forms, though as a general rule-of-thumb solid bronze castings should be no more than 1-1/2-inches thick maximum -- anything thicker will tend to deform as the molten bronze cools and shrinks in the mold.

In practical terms the thinnest areas of the model for casting should be no less than 1/8-inch, and twice that thickness would be preferred for the wall of a hollow casting. Small surface details can be made thinner, but only if in sufficient contact with substantially larger masses that will prevent premature freezing or 'cold shuts' when the molten metal is being poured into the mold.

Shrinkage is not an issue with cast iron.

[Mimiche]

thank you to direct me to a distributor for victory brown wax I'm in Louisiana
Michele

[joaopedro]

Hi!
I've recently melted some wax from candles into cylindrical molds, and got some nice wax cylinders in which i'm planning to sculpt 1:32 figurines. I was thinking about using the figurines to make a mold out of plaster and then melt the wax out of the mold. Afterwards, I would melt lead and poor it into the mold to make 1:32 lead figurines. My question is: will the lead fill all the parts of the mold without creating any bubbles? Will the lead be liquid enough to fill the mold so that all the details are clearly perceptible? Have you got any suggestions to improve this method? Or do you know another method?
Best regards,
João Pedro

[VRMMotion]

Hi Bford,
I read the thread where you described yourself as a distributer of victory brown type wax. I need to buy a bulk ammount. What is the name of your company?
Thanks!

[dilida]

VRM,

Hi, this is an old thread you are replying to, so I don't know if Bford is still around. There has been some discussion of Victory Brown here, try searching it for all the responses. The bad news is they don't manufacture it anymore, and the best replacement, Optimus 3, is not quite the same. But good luck, maybe you can find some.

lisa

[VRMMotion]

Thanks,
Fortunetly, I have just bought a large slab of Victory Brown from a company in NYC. They call it victory brown sculpture wax, and so far its just what I was looking for! This mysterious wax is obviously making a comeback . . .

[dilida]

Would you be willing to share the name of this company?

lisa

[Indigo]

Hello!
I know this is an old thread but I wanted to thank (only 4 years late :) ) everyone who posted. It helped a LOT! I ended up getting 10lbs of a very dark and medium wax, I believe it was from eBay.
The only problem with it is that, like I mentioned, it's toooo dark! very hard to see any detail!
I will probably be buying some new wax here soon that is a lot lighter, perhaps a medium tan.
Thanks again for the input guys! I consider myself experienced in wax casting now

[GlennT]

Does anyone know of a non-toxic sculpting wax that performs like victory wax? My body is doing a serious detox from handling all of the petroleum based wax.

[WillPaq]

This stuff is nice-

http://pic80.picturetrail.com/VOL966/3964388/8262812/366202909.jpg

This guy Gary creates and sells a variety of waxes, but the one I am using on this piece is called STEAM. It melts smoothly and is easily workable when cool. The beard was manipulated like Chavant, but I will go back in with loop tools when it is cooler to fine tune the details.

Willow products- http://www.willowproducts.com/index.php

I don't know if you will find it cost effective for large pieces. Most of my work is smaller.

[GlennT]

Thanks Willpaq, I looked at their safety data and it did not look to be non-toxic, but I have sent an inquiry to them. I rarely model directly in wax. I sculpt in clay and then pur waxes from molds, but then do a lot of finish work in the wax.

[WillPaq]

Thanks Willpaq, I looked at their safety data and it did not look to be non-toxic, but I have sent an inquiry to them. I rarely model directly in wax. I sculpt in clay and then pur waxes from molds, but then do a lot of finish work in the wax.

The guy who sells the stuff is very helpful generally. This wax is also very castable. I often create a loose master in clay then mold as well and cast wax.

You might just be getting allergic to victory and maybe you'll find a different formulation has no ill effects. As far as toxicity of this stuff, I honestly don't know but it doesn't smell funky when hot, nor have I yet to get any reactions myself.

[Andrew Werby]

Does anyone know of a non-toxic sculpting wax that performs like victory wax? My body is doing a serious detox from handling all of the petroleum based wax.

[It's usually the fumes from overheating wax that cause adverse reactions, but I suppose you could get sensitized to anything. Have you tried pure beeswax? At least it doesn't contain petroleum...]

Andrew Werby
www.unitedartworks.com

[Lady Fingers]

Another little trick i've learnt to help with hand modeling in wax...I use a tiny bit of vaseline, enough to just coat my fingers and it prevents the wax sticking to me. Great for clean up, rub vas liberally on and wipe hands and tools clean with cloth.

I've even used that little bit more when smoothing the surface of the sculpture. Too much will eat into the wax and weaken it, so you've got to be careful and practice a bit.

And I only ever use a microwave to heat my wax, never use hot water any more as I can't stand the trapped water that sometimes occurs.

I also use a candle to warm my tools, even roll wax across the flame to soften it, great for softening small amounts at a time.

[SPRINGFIELD]

Indigo

I would recomend you get that book that BMBourgoyne sugested
"Figure Sculpting in Wax and Plaster".
Also there are two kinds of wax Carving Wax such as the Amaco Wax you mentioned and Modeling Wax such as Victory Brown { a microcrystaline wax]
So it helps to decide if you want to carve your sculpture or model your sculpture.

I have tried many times to use wax but it's to much trouble and too slow working for me.

The wax you mentioned Amaco is a carving wax or you can try Victory Brown {a microcrystiline modeling wax]

As mentioned Willow makes some great waxes and they have a new Wax called FUZE wich is good for both carving and modeling. To model with it you need to warm it up.
My own opinion is that wax is best for small sculptures of a couple inches or less. The only exception is using your model directly in the Lost Wax Bronze Casting process.

Even professional toy model makers first model in some other medium and make a silicone mold to finally cast a wax model in a hard carving wax to put in detail.

Chavant makes some great modeling clays some which work a lot like wax. I like Chavant NSP Medium Gray but they make a NSP Hard Gray which is a lot like wax. Also their Y-2 Clay works much like wax and like the NSP Clays {Non - Sulphur-Plastilina] Contains no Sulphur so you can make silicone rubber molds from you sculpture.

[ibmainer]

[QUOTE=Indigo;9713]Hi!

I've recently been given a whole load of casting supplies, Resin, silicone, ...

I have to say that Don Dougan is right on the money as to what he had to say (3/25) on all aspects of handling wax and casting.

I have only a few things I would suggest, having cast both bronze and alluminum. When I worked in wax I sometimes put my pieces in a refrigerator between work time. I also melted wax in a pot over an electric one unit burner, as well as using a heat gun or hair dryer (for desired affects). Wax also makes nice thin sheets if you pour it out on aluminum foil with the ends curled up.
As for armatures the only limitations were that the stuff burned out with the wax, so I have used wood, cloth, styrofoam, and even pinecones....basically anything that will burn out. You can achieve a myriad of textures in this manner as well.

[obseq]

[QUOTE=Indigo;9713]Hi!

I've recently been given a whole load of casting supplies, Resin, silicone, ...

I have to say that Don Dougan is right on the money as to what he had to say (3/25) on all aspects of handling wax and casting.

I have only a few things I would suggest, having cast both bronze and alluminum. When I worked in wax I sometimes put my pieces in a refrigerator between work time. I also melted wax in a pot over an electric one unit burner, as well as using a heat gun or hair dryer (for desired affects). Wax also makes nice thin sheets if you pour it out on aluminum foil with the ends curled up.
As for armatures the only limitations were that the stuff burned out with the wax, so I have used wood, cloth, styrofoam, and even pinecones....basically anything that will burn out. You can achieve a myriad of textures in this manner as well.

(Bold is mine)

Welcome, ibmainer,

These are certainly possibilities... I, too, went the aluminum foil route, but was recently turned on to parchment paper as a 100% superior alternative--
Foil becomes pretty tedious to remove from the wax, becoming a really annoying task when all you want is a bloody sheet of wax. Parchment paper removes from the wax immediately and is reusable. You'll never go back.

Refrigeration does work, but I prefer leaving my pieces in a container of water-- You aren't leaving your wax with food, and you are better able to ameliorate any tension on the joints of your work, (all obviously depending on the size and complexity of your piece).

[racine]

or pour [not too hot] onto a fresh damp plaster former. if glass is used to form the surface of the plaster ittl be right smoothe for a while especially if it is dampened from underneath and not immersed when rehydrating.

i imagine Glen that u have solved your problem by now? i think the beeswax idea is interesting, its been casting for thousands of years. if its headaches u r getting then its the fumes, a lot of modern foundry waxes include plastics... and those carbons arnt very nice. if so i can only reccommend better airflow.

[chris 71]

i just ordered some wax from the nearest art foundry to were i live should have it tommorrow. its my first time to try sculpting in wax . well last week i tried some jewlers wax but other then that.
ok so wondering if i can ask some of you guys that work in wax for lost wax proscess a couple questions.
i am wanting to make some works directly in the wax with hopes of sending to the foundry to be cast in bronze.
if i am making small things like the size of the piece that will showed can they be just burnt out of the ceramic shell and then the bronze poured right in solid?
what kind of limitations are there before things are to thick and then you are having to make a mold to pour the wax into in order to regulate the thickness? im wanting to avoid this. and go strat from the wax piece to the bronze. thanks for any tips you care to share chris..

[dondougan]

Hey Chris,
You can cast bronze solid up to about an inch-and-a-half thick maximum (about the thickness of the narrowest part of my wrist) -- anything thicker starts to deform as it cools from the molten state.
Working wax directly saves that technical detour of making molds for the hollow castings, so it is much more immediate. The down side is that you don't have any back-up if something should go wrong -- it is a one shot deal. For me that is part of the attraction of directly-working wax -- living on the edge. <grin>
Seriously -- I don't do editions, and even when I use molds each wax casting is further worked to unique pieces by altering the textures and forms from the original casting.

If you want to work the wax as a modeling medium break then cut it up into small nut-sized chunks and put the chunks into a container of warm water. Use the wax to build up your form while it is warm and pliable in hour hands, and it will harden as it cools to room temperature. As Ladyfingers mentions above, this method sometimes traps a little bit of moisture in the wax which can be a problem if you are trying to remelt and reuse the wax later -- but if you are only using the wax to achieve a ceramic-shell waste mold it should not cause a problem. After the modeled form has cooled you may smooth surfaces or add textures with hot tools, or further sculpt the cold wax by carving with wax-working files. Petroleum jelly, kerosene, mineral spirits, turpentine all can be used to soften the surface to aid in further smoothing, or to facilitate the carving of the form by appling to the surface of the metal tools to prevent the tool sticking to the wax. Again, as Ladyfingers said a little goes a long way and so should be applied sparingly to prevent a gummy mess. I sometimes use dampened cotton rag to wipe the surface and do some gentle surface contouring, constantly folding the rag over to expose fresh surfaces free of the gummy wax build-up that develops. When the wax is cold (in the winter in my unheated studio) I sometimes use scraping actions with edge-tools to smooth surface contours.

As ibmainer said, you can incorporate things that will easily burn-out in the wax form to achive specific textures and effects. For instance, in your faces/heads with the flowing hair perhaps instead of modeling the hair you could use strips of torn paper or string dipped in wax, or a wax-coated fabric drapery for a hood or cowl. As long as you keep the material both thin and combustible this should not cause problems for the burn-out at the foundry. Thick materials can be used (i.e., solid wood), but might significantly increase the required burn-out time and so the foundry would need to charge you more money for fuel, etc. Let the foundry folks know if you incorporate anything as it can affect how they would need to work with your models.

The bronzes from a foundry class pictured here << http://www.dondougan.com/finishedbronzes.html >> were all directly-worked in wax without intermediate molds except for Lindsey Mitchell's hand (which was hollow). Jon Pellitteri's and Dusty Emerick's forms were both built from slabs and have openings to the interior so they are not solid. Lisa used rope coated in wax to make her bronze knot-pieces. Joseph, Dustin, Sarah, Diantha, Katya, and Laura all worked the wax directly and cast solid forms in bronze. Jon and Sarah were the only two students who had ever worked in cast bronze prior to this class, and Joseph had worked in clay in previous sculpture classes, but everyone else was a first-time sculpture student.

Don
www.dondougan.com

[chris 71]

thanks very much don you are always very helpful:) and i enjoyed the pictures too.
i think this is a really good thread. cant wait to have my first lost wax:)

[Andrew Werby]

I basically agree with Don's comments above, but I've never had very good luck when getting wax involved with water or solvents. If all you're trying to do is soften it, use a heat gun to change its state from bendable to soft to sticky to liquid.

Yes, you can cast things solid, but it's not good practice. Bronze really doesn't like being cast more than about 1/4" thick. Heavier sections than that tend to incur shrinkage porosity. This happens when the metal cools - as it cools, it shrinks. Since it's a big lump of semi-solid metal at that point, the parts that cool first (the extremities, if this is a figure) draw liquid metal from the areas that are still hot (the torso). This caves it in, and also causes cavities to form from capillary action. The solution is to provide a reservoir of hot metal for the shrinkage to draw from that isn't part of your piece. In some cases the pour cup can work that way, if its volume is larger than that of the area it's attached to, and it's kept from cooling too fast. In other cases, you'll need to attach special shrinkage risers to accomplish this - it really depends on the exact configuration of your piece.

I'd also advise making a simple mold of anything you're attached to, and casting a replacement wax, in case the original doesn't work. Somehow it's always the favorites that don't survive...

Andrew Werby
www.computersculpture.com

[mctc]

just bought "Figure Sculpting in Wax and Plaster" today. Amazing book and perfect level of information for me. I am excited to switch from lost foam to working with wax soon.

[SPRINGFIELD]

just bought "Figure Sculpting in Wax and Plaster" today. Amazing book and perfect level of information for me. I am excited to switch from lost foam to working with wax soon.

Lost Foam? Are you going to be casting metal yourself? If so please be careful. Lost wax as I hope you know is much different than lost foam.
I once made a mold using plaster and sand over a wax model. Baked that mold all day at 450 degrees F. Anyway the aluminum sputtered like crazy and the only thing that saved me from being injured was that it was a very small mold.
What I've read about lost foam is that you make a foam model than make a sand mold around it and pour the metal. The lost wax method of metal casting involves a whole lot more.

[Andrew Werby]

Lost Foam? Are you going to be casting metal yourself? If so please be careful. Lost wax as I hope you know is much different than lost foam.
I once made a mold using plaster and sand over a wax model. Baked that mold all day at 450 degrees F. Anyway the aluminum sputtered like crazy and the only thing that saved me from being injured was that it was a very small mold.

[That happens when there is residual wax left in the mold. It volatilizes quickly when the hot metal hits it, and forces molten metal back out the top, like a volcanic eruption. You don't want to be standing around when that happens. Your mistake was in the temperature - it sounds like you used a home oven for the burn-out, which doesn't get hot enough. In order to get rid of all traces of wax, you need a kiln that will achieve at least 1100F, and some people go as high as 1250F (Higher than that and you start to deteriorate plaster-based investment, although ceramic shell can handle it). Inspect the inlet to the mold before pouring - if you see any discoloration or soot, it's not completely burned out - put it back in the kiln and try cooking it some more.]

What I've read about lost foam is that you make a foam model than make a sand mold around it and pour the metal. The lost wax method of metal casting involves a whole lot more.

[Right - the loose sand makes this possible; it is porous enough to vent the fumes caused by pouring metal directly on the foam. Don't use bonded foundry sand for this, since it doesn't have enough porosity. And this method only works for styrene-based foam (Styrofoam, beadboard, or EPS). Urethane foams produce extremely toxic fumes when burned that can kill you.]

Andrew Werby
www.computersculpture.com

[mctc]

Lost Foam? Are you going to be casting metal yourself? If so please be careful. Lost wax as I hope you know is much different than lost foam.
I once made a mold using plaster and sand over a wax model. Baked that mold all day at 450 degrees F. Anyway the aluminum sputtered like crazy and the only thing that saved me from being injured was that it was a very small mold.
What I've read about lost foam is that you make a foam model than make a sand mold around it and pour the metal. The lost wax method of metal casting involves a whole lot more.

Yeah I will be doing the casting. Thanks for the concern. I will be very careful to get full burnout of the wax. I have had opportunity to see what even a tiny amount of moisture can do with molten metal and i don't want any volcanos.