The Foundry Cart Frame - We Get A Start

Over the Christmas holidays of 2011, I picked up some 3/4" square tubing at Superior Metals and cut it up into bits and pieces to make a cart for my foundry.  In about 2 hours, the frame was all welded together.  In another two hours, I had the welds nicely ground.

Here's some views of the frame for the cart.

However, when I re-examined the frame and compared it to the foundry, it was obvious that 3/4" square-tube steel was too light.  So, it all had to go into the scrap bin.  Oh well, chalk it up to a learning experience.  (We managed to give it to someone who could use it for something else.)

A couple of weeks later, I visited Superior Metal Centre and picked up some 1" square tube.  This had a 1/8" cross section which resulted in a much more rigid frame.  Here's a photo of the frame complete with cast-iron casters and the foundry lid-lifting mechanism bolted on.

The Foundry Cart With Lid-Lifting Mechanism

Needless to say I gained a lot more experience with MIG welding in fabricating this second cart.  

I had previously acquired a 20" diameter gas pipeline steel pipe that I prepped for the body of the foundry.  This involved trimming the ends of the pipe so that they were square with the body of the pipe.  

Next, I had to cut two circular disks from a piece of 3/16" steel plate with the plasma cutter - one for the bottom of the foundry and one for the lid.  I next cut 8" circular holes in both of the steel discs.  The hole in the bottom piece served as a "drain" in case I spilled some molten metal inside the foundry.  The hole in the lid piece would allow me to "charge" (fill) the crucible with metal, and to let the hot gases escape.  

Inside the Foundry Body Steel Disc Welded To The Bottom

With the foundry body completed, I next turned to the lid.  I had a piece of 3/16"x 6" piece of steel rolled so that when I stitched it up with some weld, I had a 20" diameter ring that would fit on top of the foundry body.  

I then took that second 20" diameter steel disc and spot-welded it to the steel ring.  I now had the "lid" for my foundry.  

Inside The Lid

I wanted to have an "infrared reflector" sitting on top of the lid so as to reflect the heat back into the body of the foundry.  The reflector had to be 6" off the top of the lid.  In order to do this, I drilled a series of 3/8" holes around the lid opening.  I next welded some 5/16" extension nuts onto the underside of the lid.  Because the heat from the welding warped the thread of the extension nuts, I had to re-thread the nuts.  With the nuts rethreaded, I next installed some 6" bolts into the top of the foundry lid.

Inside The Lid With The Extension Nuts

On Top Of The Lid With The 6" Bolts Added

When the lid was lifted off of the body of the foundry and set back in place again, I wanted to make sure that everything would align properly.  The last thing I needed was to mess around trying to align the lid with the foundry body with red hot molten metal.  

To do this, I added some weld to the outside edges of the lid.  These welds would serve as "registration marks".  Using my copper plates to build up the weld, I added weld to the edges of the lid so that, when the lid was lowered onto the body of the foundry, the lid would settle exactly on top of the foundry.  

With this work done, it was time to see if the lid would fit on top of the foundry body.

The Lid Fitted To The Foundry Body

Next was to attach the foundry body to the foundry cart.  I drilled 3 holes through the bottom of the foundry body and into the cross-pieces of the welding cart.  I made sure all 3 holes lined up.  I next welded extension nuts on the inside of the foundry so that I could screw 5/16" bolts through the bottom of the foundry cart and into the foundry body.  This would securely attach the foundry to the cart.  While this was quite the exercise, I did manage to succeed without making the air too blue with my swearing.

With this part completed, I next turned to the lid-lifting mechanism.  This required a bit of thought.  I came up with the idea of a trailer jack bolted to a 3/16" steel plate welded to the foundry cart.  This served as a base to attach the trailer jack.  I drilled some holes in the base of the jack which aligned with the holes I drilled into the 3/16" steel plate.  A bit of a learning exercise but I managed to succeed.

Foundry Body Bolted To Cart.  Lid-Lifting Mechanism In Place

But would it work!?  Time to try it out. 

Does The Lid-Lifting Mechanism Work?

Eureka!!  It works!!  I turned the crank around several times and saw that the lid was lifting off the body of the foundry!  With the lid separated from the body, I could then swing the lid out of the way.  This would allow me to lift the crucible of molten metal out of the foundry.  

With the foundry body and the cart completed, I next have to cut a hole for the burner, install the burner holder, and start adding refractory to the foundry body.

While I'd like to say this all took place within a short period of time ... it didn't.  With a lot of off-and-on again and on-again-off-again, I managed to get this far in about 18 months.  In the meantime, I had lots of fun doing it.  I managed to greatly improve my welding skills.  I also had to do a bit of thinking about how I was going to assemble all of the bits-and-pieces of steel. 

A very good exercise in thinking things through to the end before starting to cut up the bits-and-pieces of steel.