Metal Casting at Home Part 27 Core Box making with Plaster of Paris

[@myfordboy]

I agree I haven't mastered the Plaster of Paris consistancy. On a previous attempt on another project I had it too wet and a layer of water formed on the top. I'll give the soap a try too.

[@MrGoosePit]

It is a pleasure to watch you work. A true artist and master! Thanks for posting all your great videos. -Kevin (Chicago)

[@ratonbor1]

Best channel on youtube. Great men. Great hobby. Thank you for you work! Hello from Russia!

[@TerryD15]

Hi , I enjoyed this process, it reminds me of making slip casting moulds in Plaster of Paris at college in ceramic classes. We used exactly the same methods to produce the female moulds. Just a tip for future, Plaster of Paris should be more liquid when poured, the consistency of thin cream, We used soft soap for a release agent - works a treat. Two or three days is long enough for the mould to cure remove pattern before the mould dries too thoroughly - easier to fettle..

[@piranha031091]

In France, sodium silicate can very easily be found in hardware stores. It is used to reduce concrete's porosity, to make wood less likely to catch fire, and a number of other uses. It is probably the same in the US. And if you still can't find any, youtube user NurdRage made a great video on how to easily synthesize some.

[@myfordboy]

Thank you for your suggestion. I am now using a different core material ( see video 33). The sand needs ramming into the core box so I don't know if the product you suggest is up to that but could be worth a try.

[@willfrost]

I hope that you are making a bunch of those cores to justify all the hard work that you put into that mold. Also, that casting looks great. Please show us some pics of it after machining in a future video. Cheers!

[@IlluminatedWhiteGuy]

Thanks for sharing your skills! Great videos, love them all...

[@bilboproudfoot]

Is the core supported by the mold during the pour? PVA is thermoplastic. What keeps the core together? Oh, thanks a million for all your hard work. Truly inspiring.

[@BITTYBOY121]

Happy new year David! Thanks so much for making this first class video! - I found it very interesting and most helpful for my next casting session - which involves making up sand cores using Sodium Silicate (Water Glass) and CO2 (Carbon Dioxide) to make the cores needed to get the hollow areas for the inside of two motor end shields which I am going to be casting shortly for an Universal electric motor which I want to build (from electrical parts I have) to drive my small Jason metal turning lathe from the 1970's. Will keep you posted! ;-)

[@grutnip]

Thanks for taking the time to pass on your knowledge

[@elvis459]

I greatly admire your skill and patience, you are a true craftsman. Just wondering if it might be an idea to use a couple of eye screws instead of regular screws to help get you parts out of the mould, you could screw them in by hand and they would have more to grip than a screw does.

[@myfordboy]

The perlite is added to fire cement to make it a better insulator. It would be cheaper than pure cement which would crack at the thickness required. The perlite is good for aluminium but if you need a greater temperature you should use a proper refactory.Try Artisan Foundry Store and say myfordboy sent you.

[@myfordboy]

The core is held together by the 2 parts of the sand core. Video number 10 in this series shows one being used. The PVA holds up to the metal temperatue well though, I have used this method without support from the moluld.

[@puntylicious]

this is genius! so many useful techniques :)

[@verdatum]

In my experience, I've found that Johnson's paste-wax, followed optionally by a bit of silicone oil works much better as a release agent from plaster than Vaseline. Also, your vids are amazing.

[@Spydwar]

Truly funny I was watching this video and had just asked Emulsion paint what is that? Then it popped up just as I asked "Latex paint for U.S. viewers". Love your videos.

[@myfordboy]

The sand for the core is builders sand. In the UK we call it sharp sand (for rendering).

[@Aqzaqa]

Great video. Nice to see someone default to hand tools.

[@myfordboy]

Screw eyes would work well.Good idea.

[@armandohernandez-pd7kq]

excellent videos man regards from mexico.

[@65BAJA]

Love watching your videos. Could you make more vids of the machining you do to the parts after you cast them?

[@myfordboy]

I am using 8% Sodium Silicate by wieght. We don't realy have a grit system of rating the sand in the UK. Couldn't bake it without damaging the wood box.

[@anivlalbeagle3171]

this is work and a great vid. THANK YOU

[@myfordboy]

It's made of wood with standard woodworking tools.

[@juliussnyc]

Love your vids -- thanks!

[@finster101]

I love your videos. Very informative and a pleasure to watch. I look forward to seeing more. Is the sand you used for the core, green sand? Did you add other things to it prior like clay or just the sodium silicate shown in the video? Thanks!

[@Lk_yt124]

Have you considered using polyurethane or silicone casts instead of plaster? You can use them to create drafts and molds for "sand cores". They are flexible which could come handy when creating more delicate cores. A few examples how to create them can be found (for example) freemanmfg channel

[@railwaybob1886]

What is "PVA" glue? It looks like a white wood glue.

[@nothingoriginal8829]

great job

[@stickytwat]

I noticed you didn't need to reverse the turned part and you sawed one end off. Was it to obtain greater precision turning between centres using a lathe dog instead of the chuck? Plaster of Paris expands and sticks like hell when set, I find a larger draft and lots more release agent helps removal. Also I stick my patterns down flat with petroleum jelly to prevent creep, its also good for silicone pours.

[@myfordboy]

+STICKY_Inventor The part started off square so it is not possible to locate it with the parting line true using a chuck.

[@stickytwat]

Ah yes it was square not round and no four jaw thanks

[@myfordboy]

Ebay seller, I'm in the Uk, don't know what there is in US.

[@feenixb1o7]

Can you use just pure fire cement to make a furnace? Or should I try and get some proper refractory stuff?

[@SlayingBB324]

A little tip I just thought of. Use food coloring in the plaster of paris to figure out what peaces are what. Just an Idea

[@SlayingBB324]

10:11

[@metalmorphist]

Good stuff. I am still working on furnace modifications to get back to pouring. Is the sand you are using a basic "play" sand i.e. #2 Monterey (silica) of something else. I need to look into access of Sodium Silicate. Thanks much

[@muskokamike127]

HA you answered something else that I always wondered: How would turning wooden pieces in a metal lathe work out? LOL....I knew you can't turn metal in a wood lathe but not the other way around...

[@samosdolphins123]

love watching your videos. can i use any type of fine sand mixed with clay as a starter ? i cant find these specialised sands in my area

[@myfordboy]

You need silica sand and bentonite clay. 10% clay is a good starting point. Every grain of sand needs to be covered with the clay . It's normal to rub the parts together mixing is not good enough. There are videos out there showing this. I tried it once with limited sucess.

[@samosdolphins123]

thank you @@myfordboy

[@TerryD15]

PVA is a generic name for white glue commonly used in wood and paper work. "Polyvinyl acetate is a component of a widely-used type of glue, referred to variously as wood glue, white glue, carpenter's glue, school glue or PVA glue." - Wikipedia.

[@myfordboy]

See my video " Model Aermotor hit and miss 8 cycle engine" to see the finished engine.

[@mariuszmoryson2369]

A co do terminu to

[@Spydwar]

Where did you get the valve for the co2 container?

[@deankay4434]

@William Phipps - I have never seen a tank of CO2 gas, but the tank size in the US looks likes propane or Mapp gas and may use the same valve they use on torches, with normal right-hand threads. I could ask at my local welding/gas supplier to find the CO2. I have 5 propane bottles & 3 torch valves. Heating to solder upside down often get drippings into the torch tip that I have tried to get out without luck! I kept them anyways. Bet the screw right on after all, it’s not acetylene with left hand threads. It’s worth looking into as this was a very interesting video. I am a automotive repair tech, not a enough wallet to buy fancy Billet brackets so I plan on making my own for a 2003 Tahoe EFI engine to fit my 1967 C10 truck. A guy has to have fun right?

[@GrandpaBill]

You don't say how much Sodium to how much sand -- it looks like about 6 oz sodium to ?? pounds of sand? Do you have a set rule for the mixture? What grit is the sand? 180 or higher? FYI: If you're in a hurry to make your casting, you could bake the core for a few hours. Grandpa Bill

[@pancary1]

don't have a side lathe to core not spin ?

[@beneneto2008]

how you make the pattern, what kind of machine you used 3D??

[@fiskusmati]

What is plaster of paris? It must be sometnig very popular, but in my country it has diferrent name. Is that just gypsum powder, or wall finishing coat? Help!

[@myfordboy]

Just do google search for plaster of paris.

[@fiskusmati]

myfordboy i have done it, but it is not clear

[@debodevil6974]

fiskusmati Plaster of Paris is a white powder mixed with water that was used to patch up bomb damage to the Eiffel Tower and other buildings in Paris during the war. It was made of the left over bones from all the frogs legs the French were consuming at the time. The white colour was a bonus as the more the French repaired Paris with there plaster the less the Germans could see from the air when they did there bomb runs. As you can imagine being a German pilot it was hard to see where to bomb, when they looked down from there planes and everything was white! All this thanks to frogs legs. 🐸👍

[@justinberry3991]

Ha you had me til lathe.

[@Cjm7603]

Great videos +1 sub

[@myfordboy]

The sand for the core is not greensand just plain buiders sand. More details at myfordboy.blogspot.com look at the Core Making page.

[@GrandpaBill]

OOPPPSS My bad... forgot about the wood frame -- that would really smoke up the house if you put it in the oven at 400 degrees...{8-0) Grandpa Bill

[@NLB90805]

Shit howdy mate, that last bit didn't want to come out now did it?

[@TheKutia]

Hey i want to cast my own box for a vape out of brass, do you have any ideas on how to ache-ave this?

[@myfordboy]

I have no idea what your part looks like but casting brass is not the best way to start casting.

[@TheKutia]

I started with aluminium from my pop cans but i cannot figure out how i would go about making a box with a lid

[@puffles234]

pva is the British term, i think 'pva' has something to do with the chemical formula

[@boinkboink1968]

Can you add sodium silicate also to greensand?

[@myfordboy]

No need to use greensand just use silica sand.

[@lolailomen]

to-morrow I want to be like you

[@Aqzaqa]

this video made me want yogurt

[@joshmnky]

If you start casting metal, make a lathe first ;)

[@chronicsmoker_]

this is not news paper comics