What to cast first??.......

That is the question....

This weekend I want to try a proper casting; something useful that looks more like a "thing" than just a blob of metal. I wanted to start off easy by building a lathe. However there is so many things I'll need for that become a reality, not to mention the various failures on the castings that I will inevitably suffer.

I decided I'm going to try for a 4 jaw chuck as a first attempt, as this will be useful in both the lathe and as the chuck for the 4th axis on my CNC machine. Another good reason to start off with it is that it's quite a complex piece with many slots, pockets, bearing cups and such.

The method of lost foam casting is one very predominantly used in industry today. It basically involves cutting a desired shape out of normal EPS foam (Styrofoam) then dumping that "blank" in some ceramic material to create a smooth surface around the blank, then pouring in the metal, the metal will burn out the foam and fill the resulting cavity with metal and voila you have a metal part the shape of the original blank.

I will use my CNC (Computer Numeric Control) machine to cut out the blanks in foam. I built this machine about a year ago from two old dot-matrix printers and a few bits of MDF wood. It's not the most accurate thing on the planet, but it saves me a lot of effort in creating the blank.

This is the design for the chuck main body I have in mind.

Designed in Rhino 3D
















Hope this gives you some idea of what I'm aiming to do.











Here is a few shots of my MDF CNC machine... this will be used to cut the foam patterns for now.



I'm in the process of building a much bigger and way more rigid machine than this one, but for the moment, and seeing as I work with a very soft material Styrofoam, This cheap and easy machine will do.










Starting the first outline cut for what will become the lathe chuck.

You will probably need to click on the picture to see a bigger one if you can't see the circle being cut out.









My trusty old laptop. This poor thing have really been through the wars. I use it regularly to prop up stuff when grinding, or as a coffee cup coaster, since it's surface is about the cleanest thing on my workbench... Despite it being held together by self tapping screws and coffee stains it still keeps on working.

It's running TurboCNC v4.0 which converts the g-code language to pulse signals to drive the motor electronics.


In a later update I will go through the steps involved more thoroughly. We will also be building the BIG machine together.

Here is a short video clip of the router cutting out the foam blank.

My first Aluminium melt!!!

WOW!!

I know it doesn't look like much, but I actually created my very first aluminium ingot!!

After waiting out the rain all weekend I couldn't hold myself any longer, so I took an old motor bracket I had lying around and after starting up the furnace I dumped it into the crucible.


I wish I could get pictures or a video of the aluminium melting, but it's so hot around the furnace I don't want to risk messing up my cellphone by taking the pics or video... Suffice it to say that it just looks to amazing seeing that bracket turn into a plastic like consistency and then eventually just becoming a pool... It was so cool!!




<--- Note the special safety equipment!!
A pair of "vellies"...

Please don't do this if you build your own!!!
You will get burned!!!!!! badly!!!






I was rather surprised at how easily the aluminium melted, the crucible just barely turned red and it was a pool already, I had that crucible glowing white hot without aluminium and still didn't believe it would be hot enough..... Oh how wrong that was ...



This is the pool, it's not a lot but still enough to get me helluva excited! finally a Eureka moment!

See the slight red tinge to the crucible....

It only took about 5 minutes from when I dropped the piece into the crucible till this pool was made. I've seen the future!! and it is waste oil!







Since I haven't gotten around to actually welding up a proper ingot mould I just dragged my foot in the dirt to make a little "ingot mould" and poured it in ...


Look it's SHINY!!!
The ground was very wet and I could see the aluminium bubbling on top, that was the water underneath boiling and the steam vapors bubbling up through the melt..

Still I managed an ingot.

This will forever go down as my FIRST... and nothing will take away from that fact.. It now has a very special place right along side my collection Ferrari F1 memorabilia.

The lifting tongs.

As the name suggest this is a tool used to lift the hot crucible from the furnace... Trust me a red hot crucible filled with molten metal isn't something you want to tackle "hands-on".. I made these tongs to ensure once the crucible is locked onto it there is no chance of it falling out or slipping and spilling the hot liquid metal.




It might be a tad over-engineered, but hey that's my way.

Centering the burner oil tube

This weekend had been quite a productive weekend. A lot of things got finalized like the lifting tongs, the trolley and the burner.

I had a problem that the oil tube in the burner wasn't aligned exactly in the middle it seems it had a bend in it, and no matter hoe hard i tried I just couldn't center it up by normal bending it in place, so I made a sort of "aim adjustment" setup.... was quite a simple and straight forward idea, but welding those 4mm nuts on was quite a hassle, the normal arc welder I use just burns the nuts away. Just be very careful and it eventually works.



Just 4 nuts and the matching bolts welded to the air tube of the burner. Remember to drill holes for the bolts prior to welding.














Result!!!!

<---- centered oil tube.

No Work done :( ---->But look at it .... LOVELY!!!

Well Like the post heading suggest there is no work currently being done. I was busy making the lifting tongs to handle a white hot crucible filled with molten metal... A very elaborate piece of equipment if I must say so myself. I hope it works! Will update you in a later post.
But for now nothing is getting done.











<---- NICE!!!! Damn I love the rain.



Namibia is a very Arid and dry place. So when the rain do come it's a sort of religious experience for me. Time to sit indoors and reflect.

.... and after much "reflecting" ... I've come to the conclusion ....... I LOVE THIS PLACE!!!! You can stick your 1st world amenities right up your bums!!

Africa is where my heart is.

Johann out!

It really really burns!!

last night I simply couldn't wait to get home from work. There were heavy clouds in the sky, and I wanted to fire up my burner and furnace combo for at least 5 minutes to see if everything will hold up.

this is the result....


This is the setup I'm using now.
This thing is scarily heavy so I "salvaged" a shopping trolley cut the basket off and made a push-cart to move this lump of concrete around.



This post courtesy of Trade Centre pty.(ltd)



I will get around to replacing the bricks holding the burner up for something more permanent..
I'm still looking for a way to modify that blower as well. I blows way too much and having it that far away is just a waste of energy.

This is after all a very "green" environmentally friendly machine. It burns old used motor oil... yeah that black stuff they replace when doing an oil-change on your car. Yep! So the environmental impact stems from the fact that that oil aren't left in some landfill outside town, it gets used to generate heat which does useful work.

Though in all honesty I use it because its cheap!!

Okay here is what used motor oil looks like through my burner... this thing is scary HOT!..


I love this pic. just look down into the very bowels of hell!











another one.


















Tonight I will fire it up for 10 minutes to see if the refractory holds up...

Will let you all know how it goes.

FIRE!!!! Testing the burner.

Right ... Last time we built the burner assembly. Now it's time to test it.

I wish I had the furnace at hand to test the burner, but alas it's still drying... and taking it's sweet time.

So seeing as I don't have the furnace, I'll be using a normal coffee can. Keep in mind it's just to test whether the burner actually work.

I cut a hole in the coffee can, big enough to fit the burner nozzle and then I made a small fire in the can using wood lying around..

After things are heated up properly i open the valve to let the oil in, you can definitely hear the oil is vaporizing in the chamber, it's sort of sputtering to life...

Open the valve a little more ... it's still sputtering, more frequently now, but makes a helluva lot of smoke ... give it more oil!!!



OMG!!!! it's ALIVE!!!! It sounds like i just ignited a rocket engine. there is a definite difference in the ambient temperature around the area, this thing burns!!


NB! Note how far away I had to place the blower away, if I have it any closer it start blowing the glowing embers right out of the can.

Also I didn't hook up the oil tank and the feeder pipe, I simply put the valve at the burner and attached a plastic top to hold the oil... this is just a test to see if the burner ignites.




Another burn picture. See the tank assembly lying to one side... that will be used later.
















If you click on the pictures look at the can you'll see it turned a nice red, and that was after about 10 seconds from opening the oil and finding the right mixture. I immediately shut it off, I didn't want the can to melt through and light the whole suburb alight.


... next i will have to fire with the furnace.