Sand Fluffer, Surface Finish...
And a 2nd Pyrometer
I
thought that this page was done a few weeks ago, but as I was setting-up to post
installment # 13, I realized that 12 was not posted yet...
Since the Bench will be staying where it is, I scrounged a few shelves for misc tools and storage.
This is a proto-type Auto-Riddle or Sand Fluffer... The original Electric mixer is set into a wheel barrow and a 1/4" mesh screen is bolted into the bottom of a 20liter pail.
As a proof of concept the idea works great...
The sand that comes out of the back is perfectly sifted and has a superior compactability than the 1/2 Riddle offered...
As well as the complete mixing of the blackened fines back into the sand. Not to mention the fact that labour is reduced and the rate of production increased.
So this is the assortment of sand sifters or riddles that I currently use.
The Coarsest is the 1/2" square framed unit that quickly busts the dense mold chunks down, the 1/8" mesh that fits into the auto riddle, and the original Ultra Fine screen that still fits into the Electric mixer for cleaning the loose sand for LFMC production.
This is a quick shot of some Crucible production... I opted to drop the 4 other pictures that got the 3 tanks to this point.
The panic that sets in when a pot let's loose is less pronounced now that I make an effort to keep spares on hand at all times.
As soon as the last pot is put into use, the next three pots will be made...
The images above are getting to be familiar routines, measuring the melt with a real Pyrometer, and lancing the melt to degas the melt prior to pouring...
Also note the addition of more Safety gear, Shin leggings and real fire retardant mitts (These were an Xmas gift from my dad & sister)... I'm sure that their thoughts are not if, but when something goes wrong these should minimize the fallout... I'm most grateful...
The above pattern was one of my first problems with the new Cope & Drag system, after numerous attempts this pattern simply could not be extracted without damage to the mold.
Over the course of several days and getting an education in what makes a pattern unsuitable for Cope & Drag, I went back to the old LFMC, but with a true vertical position and well curved feeders. The results look good to me, and the absence of major porosity defects give the Degassing process some credibility.
These plaques are an argument for refining scrap prior to pouring... The pronounced "Frosting" on the face of these units is from a series of un-known alloys that were direct pours without being poured off as ingots first... Not that I have too many concerns about the structural integrity of plaque type castings, I do tend to watch for frosted ingots and dilute them with more pure Alum alloys that have a more shiny and homogenous finish.
Next term I'll be taking a Metallurgy course and all will be revealed... The larger foundries use spectrum analyzers to make definitive identification of alloys... Until I determine how complex an analyzer is, I can dream about the day when I have my own (then reality will strike).
This is a second Pyrometer that I was lent briefly, it functions exactly as the other one, but uses a "J-Type" thermocouple with a ceramic bead on the end... I just noticed that the bead is broken (I hope that wasn't me...)
I included this picture, with the thought that, the space that the back-hoe occupies for the winter could be better used for an indoor Furnace area.
The idea is to use steel studs and sheet metal, and line the 2 corner walls, install a lowered sheet metal ceiling and a huge exhaust hood.
As this is a project that will have a significant capital cost attached to it, there will be much wringing of hands and general anguish, before I actually crack my wallet open and spend a single red cent.
I see a ripple effect occurring here where another building will have to be fixed-up to house the "Hoe" before I can move on this.
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