Home Lost Wax Casting On The Cheap: Step Five, Vacuum Plate

There are two kinds of casting people normally do at home in regards to lost wax.  They either use a centrifuge, or a vacuum plate.  In a centrifugal setup the hot metal is poured into a special crucible, and then spun madly to fling the hot metal out into the molded investment.  See below.

Or vacuum plate casting, where the hot metal is poured down into the molded investment and then a vacuum is used to suck the air out of the investment making sure that the hot metal gets into all the little nooks and crannies. See below.

I am going vacuum plate, because its slightly easier to fit into my current sized (aka: small) studio.

The basic idea is you have a flat metal surface with a high temp silicon rubber gasket, you somehow get a small hole in the base of that flat area for the vacuum hose to come up under the flask/gasket combo, turn on the vacuum pump, put the flask with hot investment on top, pour in molten metal.

I got almost all of the stuff for this project out of dumpsters, so I started by cleaning up an old nasty board I found.







I cut it roughly 10 inches along one side, with the assumption that the “business area” is about a 4x4in square centered around the center of the block, so this is plenty big.  Try to get the edges and tops as flat as possible, I used a rotary disk sander with some 120 grit on this for a couple minutes to clean it up nice and smooth.

Next I dry fit the “plumbing” I used 1/4 inch brass NPT (means they have air tight pipe thread on them, which you want) fitting. These included the following parts:

dixon valve ttb75 ptfe industrial sealant tap ($2)

Anderson Metals Brass NPT Pipe Fitting, Barstock street Tee 1/4″ female Pipe x 1/4″ Male pipe X 1/4″ female Pipe ($5)

a 4 inch piece of Red Brass Pipe Fitting Nipple Schedule 40 Seamless 1/4″ NPT male pipe ($4)

and a stainless steel (they were out of brass) 1/4″ NPT pipe mushroom style cap ($1)

A 1/4″ npt threaded ball valve to Barb ($3)





The top threaded part is “up” so that will be what sticks up through the plate to suck the air out of the flask.  You will notice that I have placed a large section of pipe that goes “down.”  The reason I did that is because if there is a catastrophic flask failure and molten metal pours down into the hole it will flow straight down into the pipe instead of down the hose into the vacuum pump jacking it all up.  The square sides on the valve make it fit really well later in the process, so if you can find that kind do so.


When you do the final fit, be sure to wrap all the threads with the ptfe seal tape to get a strong airtight seal.


Next I measured a channel into the side of the board big enough to hold all the plumbing.



Be sure your plumbing will fit into the notch, and rough it out a bit more with sandpaper or a chisel if it needs more space.


Next measure the steel plate and cut a small hole in the middle of it (I used a jewelers saw) big enough to hold the threaded end of your plumbing fixture.  Line up the plate, and mark on the wood where it goes, then jam your plumbing contraption into the notch.  This is a stainless steel plate I had laying around that is a little under 2 mm thick.



You can see that it sticks up just enough to go through the metal plate, and then I affixed it in place with two screws.



Here is the bottom, as you can see the ball valve has enough space to swing to both side.  Two more screws are used to keep it rock solid.






Stick the small threaded end through the plate, and use some silicon caulk, or in my case some e6000 glue left over from the kiln vent hood.  Be sure to get a good seal and have it bulge out so it completely fills the gap and makes an air tight seal to the plate.  The plate itself is not affixed to the wood in case it ever needs to be changed out.


Be sure to let it dry fully, I used two coats to get a really good seal.


Let it dry overnight before doing anything else.  It stinks, put it in a well ventilated area.  Next I built some simple legs on the thing that would keep it sturdy and allow for the bottom drain pipe to stand up without hitting the table.






Here is what it looks like with the vacuum hose attached.






The four screws allow you to tug on the hose without anything moving around.  Next I used a high temp backing silicon pad to make the base seal, another thicker high temp silicon sheet will be added in the future to absorb the heat of a prepared flask, cut the hole just big enough to surround the glue you used.



The only thing left to do was to fire it up and test it out.  I have a vacuum chamber that I built with a vacuum gauge but this is just the plate and I didn’t know exactly how to measure if it was pulling a strong vacuum or not, until I remembered that water will boil in a vacuum, so I took pyrex storage dish and made a quick vacuum chamber and put a small glass of water inside.


It works!


Materials used:


Found wood

Dixon valve ttb75 ptfe industrial sealant tap ($2)

Anderson Metals Brass NPT Pipe Fitting, Barstock street Tee 1/4″ female Pipe x 1/4″ Male pipe X 1/4″ female Pipe ($5)

a 4 inch piece of Red Brass Pipe Fitting Nipple Schedule 40 Seamless 1/4″ NPT male pipe ($4)

and a stainless steel (they were out of brass) 1/4″ NPT pipe mushroom style cap ($1)

A 1/4″ npt threaded ball valve to Barb ($3)

High Temp Silicon Baking Sheet

e6000 glue

wood screws

Zeny® Single-Stage 3,5CFM 5 Pa Rotary Vane Vacuum Pump 3 CFM 1/4HP HVAC Air tool R410a R134, blue ($53.00)

Vacuum Hose

Tools used:

Hand Saw

Utility Knife

Jewelers Saw

Drill with Drill Bit

Rotary Sander


Total cost $68 (stuff I had to buy is priced above, everything else I had or found)

Buying a vacuum pump was a bummer, but couldn’t find one cheap or used around me, the rest was simple plumbing and some found wood.  This was really easy and can basically be used for all sorts of things.  I might end up putting a fine mesh over the vacuum hole just to keep anything from being sucked in.

I looked up a vacuum plate online, and new ones go for $400+ and they don’t even come with a vacuum pump (!).  So getting away with this for under $70 including the vacuum pump is a steal.




Home Lost Wax Casting On The Cheap: Step Four, Kiln Vent Hood

In my ongoing quest to build my own DIY home lost wax casting set up and not burn my house down, or asphyxiate myself I figured I would need a kiln vent.  Kiln vents come in two kinds, top vents, and bottom vents.  They help draw off any fumes, smoke, heat or other nastiness that your kiln might create.


Here is an example of a top vent, and one that I will be emulating.

As you can see its deceptively simple. A hood to catch the rising heat and fumes, and a fan to blow it out a window. I figure I could make this with stuff from the local hardware store no problem.


First I got myself a big paint tray made of steel and cut a bathroom ceiling fan shaped hole in it with tin snips.





Then I took that celing fan and glued it into the painting pan with e6000 glue (damn that stuff stinks, do this outside if you can)





For a power cord I used an old computer power cord, Simply cut the end off and strip each of the three exposed wires about 3/4 of an inch down.






Match white to white, green to green, and black to black.  Use wire nuts or electrical tape to carefully wrap each wire individually before wrapping the entire mess.



Attach the duct work to the fan, I used a zip tie with a small metal screw to secure it strongly to the black flange that sticks out from the fan.





Some pictures of the glue job, remember this isn’t a fume hood, it will not have to catch every single vapor from your super toxic chemistry experiments, it just has to vent hot air from the kiln out your window.  That being said, the tighter a seal you can get the better it works.  Don’t be shy with the glue/tape to close up holes.






I used two copper pipe holders to create mounts for the mounting rope.  I used the paint pans own legs on the other side as mount points.  Simply attach them with self tapping metal screws.


All done and hanging in the stand I plan on putting my micro-kiln in.


I tested this guy by lighting various kinds of smokey fires under it, and I have to say it works pretty well.  I put the grate included with the kit on over this box and the efficiency went way up (as did the classy nature of the vent hood)

DSC_0304I built this little window plug so that I could use the vent in the winter without cooling down the house too much, its just a piece of insulating Styrofoam with duct tape wrapped around it.





I had some duct work and parts left over from a previous project so I also made a soldering fume extractor out of an old impeller fan and some duct work.


The impeller fan is wires up the same way the bathroom fan was (you can see the cord coming off it.)  It also fits into the little hole in the window plug and sucks pretty hard, easily removing all the fumes from soldering and other fire related torch work.


Materials used:

Paint Pan (12$)

Duct Work (12$)

Ceiling Fan (15$)

E6000 glue (6$)

Self Tapping Metal Screws ($4)

Electrical Tape

Old Computer Cord


Duct Tape

Copper pipe mounts ($1)


Impeller fan

Tools used:

Tin Snips

Screw Driver

Utility Knife


Total cost $50 (stuff I had to buy is priced above, everything else I had or found)


Sadly I had to buy most of this stuff as I didn’t have any of it laying around, and just didn’t feel like waiting until something popped up in the trash, I know that tomorrow I will find the perfect bit of trash laying around to do this project on the cheap, but I wanted to get this done now because the supplies for my DIY kiln are arriving soon!  And if you consider that a brand new one of these will set you back at least 300$ I think this is a pretty good deal.

Home Lost Wax Casting On The Cheap: Step Three, Alcohol Lamp For Wax Carving

Another really handy thing to have is a source of heat for wax carving, adding sprues, and other waxy business.  This can be as simple as a candle, but I wanted something a little more old school, but also something with some class.  The tried and trusted way to do this is with a tiny alcohol lamp.  I could have easily purchased one of these for 8 or 9 dollars online, but I am trying to save money.  Plus I already had everything I would need for free!

Step one, find yourself one of those super cute tiny mason jars.  I use mason jars for just about everything, so I already had dozens of these things laying around.  Make sure your’s has no cracks, and that the sleeve is in good shape.


We are not going to use the middle lid (it has a rubber/plastic backing that would burn up), but we are going to use it to trace. the size of the replacement lid.


I had some stainless steel sheet laying around so I got a thin sheet out and traced the lid on it.




It was quick work with the tin snips and I had a very shiny lid replacement.  It is important that the part of the lamp that will come in contact with the flame be entirely made of metal (for obvious reasons).

Your wick material can be any fabric or rope, so long as its 100% cotton.  And old piece of jeans that I was using to sew up a newer pair of jeans made the perfect wick, denim is 100% cotton.


Drill a small hole in the middle of the steel circle.  Your wick should be slightly wider than the hole but not by too much.  Size your hole/wick combo accordingly.

DSC_0235You will need a fuel to burn, I highly suggest something intended for the job.  Otherwise you might blow yourself up, or at the very least cause a nasty fire.  Denatured alcohol should be your only choice.  Don’t blame me if you use gasoline and burn your house down…I had this denatured alcohol laying around from a previous project.



Fill the glass 3/4 full and soak the wick in the alcohol for several seconds before pulling a small bit of it through the hole.
Put the lid on securely with the sleeve and light your new alcohol lamp!



I let this guy burn for 5 or 6 minutes just to see what would happen.  You know you have done it right when the wick stays blue and only turns black on the top, that means that the alcohol is burning and not the wick.  You can control the size of the flames by controlling how much wick you pull through.  If you are having trouble with your wick burning down too fast try putting a bit more alcohol into the glass (still leaving an air space at the top), as I have found that it helps it soak up the wick faster if the level of the fuel is closer.

Materials used:

Small mason jar

Stainless steel sheet

Old piece of denim

Denatured Alcohol

Tools used:



Tin Snips

Drill and drill bit (but you could use a screw driver or punch and a hammer)


Total cost $0!

Home Lost Wax Casting On The Cheap: Step Two, Wax Tools

You want to carve wax, you need wax tools.  There are some rather dashing and lovely tools available on the internet, problem is they all cost money, money I am trying to avoid spending.  A quick google search or two confirms my suspicious that wax carving tools are basically wooden handles with steel point bits at the end.  I have some steel bicycle spokes, and a hard wood dowel that will make a lovely handle. So off I go!

I surveyed a bunch of pictures of wax carving tools online and picked the shapes that seemed to be most common.  I then set up a pico-forge on my new bench, consisting of a hammer, a chunk of metal, and a tiny torch.


I took some old bike spokes I had from an old bicycle tire, cut off the threaded bit, and sanded the powder coat off (if you have plane steel spokes you can just lop the threaded part off…or honestly leave it, I learned later that the threads probably wouldn’t have made much different.DSC_0144

You can even use the bent end of the spoke for special shapes as I show later.



Get your dremel ready for some grinding.

My pico-forge.  The smallest forge in history.DSC_0150

Heat the end up.DSC_0151 DSC_0152

Then hammer it into the shape you want.


Use a file, or sand paper, or your dremel.  And make all the other shapes you want.


The nice thing about this process is that I can forsee myself making custom one off tool with this technique for basically free.  I have about 200 bike spokes, and you only need about 3 inches of one, so you can make multiple tool heads from just one spoke.


Get your dowel, and cut it into handle sized bits, I made mine about 6 inches long so, because I have larger hands, and I thought later I might want to put a tool head at each end to make them more useful and wanted enough room for that.  And yes that is my jewelers saw with a jig saw blade mounted in it.  (Simply snip the two ends off that have the little mounting peg for the jig saw and tighten it down into your jewelers saw, you now have a precision jig saw for the cost of the blades.)


Do your best to center the holes, although a little bit off doesn’t matter.  Now drill a hole the diameter of your bicycle spoke into the end of each one.  Once that is done its time fer some good old fashion wittlin!







I took a utility knife, and carefully carved down the tips rotating and taking small chunks off until it came to a nice point for each tool.  This was the second most fun part, (playing with fire will always be number one).


Test fit with all the tools.  I set the scribe head, and chisel head further into the handle for more stability.  From left to right I have named them.  Scribe, chisel, hook, diamond, scraper, and graver.

Now get yourself a strong two part epoxy.  I like jb weld.  and goop up the base of each tool head and let it sit overnight to harden.






Let them set up overnight.




All done!







If I ever need more/different versions of these I just have to wittle down the other end and mount another tool, I also have another dowel that would make me another 6 or 7 of these.  Made entirely from found/recycled/junk parts.  I have tested these with various waxes and they do a fine job, I did take some time to carefully sharpen the heads with a fine file, which dramatically improved their performance.

Materials used:

found wood dowel

old bicycle spokes

JB Weld

Tools used:

drill and drill bit

utility knife

jewelers saw with jig saw blade in it (you could use the utility knife if you didn’t have a saw)

torch (a tiny kitchen torch works, you might be able to get away with using the stove)

Hammer (or any heavy metal thing)


Total cost $0!

Home Lost Wax Casting On The Cheap: Step One, Casting Bench

I really want to be able to do some lost wax casting at home.  I have wanted this for years, but the sticking point has always been cost.  I could go out and buy brand new casting equipment, and have the whole thing ready to go in a couple days…for a rather large price tag.

So I finally just decided that I was going to build what I need from what I have, what I can scrounge, what I can borrow beg or get for cheap.

Building a Bench:

The first thing I need is a good sturdy bench to hold the kiln, the vacuum plate, the crucible area, and a fume extractor.  I had found a giant piece of wood in a dumpster (it was a rafter, but it was warped so whoever was building a roof tossed it, their loss, my gain).  It was 16 feet long and 11 inches wide, I used 5 feet of it for a shelf in my kitchen leaving me with an 8 foot chunk and a 3 foot chunk. (that’s my home made bicycle trailer on the left, I use it for just about any large hauling job I have)



I also found an old IKEA table thrown out on trash day with a nasty particle board top that was all messed up.  The legs however were sturdy steel so I unscrewed them and took them home.  A quick spray with a can of black spray point left them all the same color, which was more to my liking.






The largest bench I could get was 4 foot by 22 inches.  The wood is pretty warped, and I have no way to fix it…so I threw caution to the wind, and just chopped it up and screwed it together.  This thing just has to sit level on the ground, and hold up a lot of weight, it doesn’t have to be pretty.




Then I put the legs on!






It is crooked…but the house isn’t level, so the damn thing fits almost perfectly into the space I had reserved for it.  With only one shim required to bring it to full level!


I had found a sheet of steel a couple years ago that I have been wondering what to do with for a while, it fits perfectly on the front of the bench making it fire proof on that side, it also covers the gap between the wood keeping things from falling in there.  The back will be built up with fire bricks and wood.

That is some soap I just made drying under the bench, and there is a bunch of junk laying on the top, that is living there for a while.  I will rearrange things as I build more stuff.  Next up is the kiln, vacuum plate, and crucible area, as well as the fume extractor, and fire brick back stop.  I will be building as many things as I can in this journey so it might take a while, but stay tuned.


(In case you wondered, the wood was free, the legs were free, I already had the paint and the screws, the metal top was free, so total cost for this bench was $0.00 and the two blisters I got screwing all those screws in by hand)