Hi YouTube, my name’s Geoff and I’m the VegOilGuy.
In my last video on Lost Wax Casting, you saw me attempt 6 – count them – SIX attempts
at achieving a nice casting, and frankly I never really achieved it.
Some were okay, but nothing ever really delivered the promise of a crisp result straight from
the foundry.
A few of you guys reached out and recommended I try lost PLA casting and one of my subs
sent over a link from Myfordboy doing exactly that.
Now I am a fan and long-term subscriber of Myfordboy and I had seen the video before,
but as I watched it a second time something twigged…
I could try applying Myford’s approach to my lost wax failures.
It made sense to pick up where I left off so I grabbed the Equalizer Two silicone mould
I’d already made and set about forming a wax pattern.
Thanks to the tips from Worldtraveler, I’m now getting consistently could results with
the wax making.
Warm the mould with a hairdryer.
Pour in some molten wax.
Swill it around for a few seconds, then empty it out.
Let things cool for a couple of minutes, then repeat.
Eventually the detail gets filled in and it’s then time to top up.
Once the pattern has had chance to fully cool, it comes free of the silicone mould nicely,
and it looks very nice and sharp.
I carved away the excess from around the edges, but the back was a little uneven.
So I preheated a saucepan and carefully lowered the wax pattern in.
It only takes seconds and if you’re careful you can smooth the back off nicely.
I placed the wax onto a backboard and screwed this in place from underneath.
I then added wooden sides ready to pour the investment.
The plaster investment was carefully and precisely prepared, then poured on before vacuuming.
It only takes a few minutes to set, but here’s the result two hours later – an L-shaped
brick.
Just a tiny bit of clean up was necessary, but I was probably being too fussy if I’m
honest, then I placed it in my foundry at 100 degrees Celsius for about ten minutes.
This was enough to melt out the wax into a container, and the remaining impression looked
pretty good.
The investment was then cooked according to the guidelines of the manufacturer and allowed
to cool.
As you can see, this looked very nice and the advantage of this approach is it allows
for some very gentle tidying up of the pattern.
But trust me, this investment plaster is very fragile so care is needed.
I prepared my green sand in the usual way and set out to copy Myfordboy’s approach.
I placed the investment pattern in the drag and covered this with sand.
I didn’t ram hard as the investment really is quite brittle, but my fingers pushed home
the sand enough to compress it into place.
With more sand added, I was able to begin ramming, but still not too hard.
Once this was completed, I flipped over the drag and coated everything with a little talcum
powder.
You’ll see why in a moment.
The cope was then filled and rammed with sand.
I flipped the cope upside down and then carefully aligned the drag on top, making sure everything
was in its correct position.
I then removed the drag with similar care and as you can see, the talc has left a faint
impression of where the pattern is.
I took a piece of pipe and cut out the feeder, failing to make it look as easy as Myford
does.
Now Myfordboy had already positioned a length of half-pipe in his cope, but I opted to cut
the gate by hand.
I used my finger to compress, shape and smooth this.
You’ll notice there’s no vent.
It’s not always necessary and judging this comes down to experience – experience I
don’t yet have.
But my pattern seemed smaller than Myford’s, so I went with his judgement and opted not
to use one.
A little very light pressure air helped clean away the loose sand.
I then placed the cope on top of the drag and sprinkled a little talc down the feeder.
Er, well, the plan was to sprinkle…
This marked the position of the feeder on the drag, and that enabled me to cut away
a small well and gate.
Again I compressed the sand with my fingers, smoothing and shaping.
I used more air to clear away any loose sand and also remove the talc, especially from
within the plaster pattern.
I gave the cope another once over with air then fit everything together.
Myfordboy fans will be used to this extended feeder method,
encouraging a little head pressure to the pour.
In the background my electric foundry had been silently melting the metal and the pour
was quick, precise and without fuss thanks to the tall, wide feeder.
About twenty minutes later I decided to pull everything apart and have a look.
As I parted the cope from the drag, the plaster investment stayed behind.
The results didn’t look too bad.
Yes there were some obvious pockets and evidence of porosity, but the lettering was nice and
the overall shape was very well formed.
With the plaster and sand washed away we can take a closer look.
Now you guys know what a perfectionist I am – I’m looking for spot-on first time and
yes, this doesn’t do that.
It’s clearly flawed, BUT if anything I’d have to say it was better than the results
I obtained in my previous six attempts, and those were done using the so-called proper
methods.
Yes there is porosity, but in fairness there was some porosity in Myford’s example as
well, so I expected that.
But my finish isn’t as good as Myford’s, so why?
Well there could be any number of reasons for that… to begin with he’s far more
experienced and, let’s be honest, more talented at casting than I am.
There’s also the way the sand mould was prepared, his was likely smoother and better
formed.
Then maybe the temperature of my metal was off.
To be frank, I’m actually not too bothered by the result, and I know that’s unusual
for me.
But the reason I’m not bothered is because this has opened up a new line of possibility
for me, one I’m more experienced with – using green sand.
So I have to give Myfordboy a nod of appreciation and extend my thanks for the inspiration he’s
provided.
Yes my results weren’t as good as his, and I never really expected them to be for all
the reasons I’ve already given.
But he has given me hope and sparked my strange mind off with other thoughts and ideas that
might help me improve on this technique, and of course by that I mean make it easier for
me to get the results I’m after.
I’ll share a secret with you – I’ve already taken another step, adding a vent
and shortening the gates and the results, well, you’ll have to wait and see.
But hopefully you haven’t got to wait long.
With luck my next video will be a Casting Challenge with my mate Perry.
If the two of us can edit our videos in time, the results should be with you very soon…
and if you want a clue as to what that video is, let’s just say, I hope I’m not Too
Weak to finish the editing.
I hope you enjoyed this video guys and found the look at other approaches as interesting
as I did, and if you did, please like it.
If you haven’t already subscribed, well why not?
I’m a desperate man.
Hit that subscribe button.
Look out for my website, my YouTube Channel and the upcoming Casting Challenge with SWdweeb.
So that’s it for now guys, take care and thanks for watching.