Work Flow & Enhanced Techniques

New Equipment & Enhanced Techniques...

processing jobs and finding areas for improvement...

Please Note that this is a rather long installment with a glut of images, so load times will seem quite slow compared to other pages on this site...

This is a proto-type "Hot-Wire Foam Cutter" that I have been in need of for some time now... My brother was good enough to give me the Variac (Variable AC Transformer) and it is the heart of the system.

The plaque type castings that I've been concentrating on are milled in 1" foam brd, but I have been using a table router to cut-back the brd to 1/2" thickness. A most inefficient, noisy, messy and inherently dangerous task I'm glad to be done with.

This is the finished assembly mounted on the flip-down condiment tray of the recycled BBQ stand cum mobile bench.

The cutter is a 11thou guitar string held taut with springs on either terminal, and the height of the cutter is set with 2 pieces of 1/2" wooden dowel.

The only draw back I've found is that the foam acquires a slight (almost imperceptible) curl from the heat of the wire. I've tried sanding the cut surface in the hopes that the stressed foam return to it's original flatness, but to no avail.

Anyone with experience or insight on how to resolve this issue please forward any advise you can offer... frnkgmbk@renfrew.net

Each job/plaque starts with a simple work-order generated within Outlook's Task Manager holding ID, Max Dimensions and cut file names.

The cut files are on a labeled diskette(s) and kept with the work-order until the job is done, and then the diskette is erased and used for another job.

The cut pieces are kept with their disk(s) and W/O in a slot. Once I get the Nex-Mill 24 completed I'll need to knock some dividers out for the larger pieces.

At some point the pieces are painted as noted in earlier pages, but with a higher volume of work, the economy of scale starts to get realized, as more pieces get done together.

In this image the pieces are painted and dry and ready for plastering.

In previous pages I'd posted that I was using "DAP" brand plaster of paris. By chance I picked up a 1Kg box of "Quick-Crete 90" by Westroc... A far superior product for my purposes.

The main problem with the "Dap" product was that it setup too quickly, sometimes in the mixing bowl as I was applying it. Great if your patching a wall after a party before Mom gets home, but those days are behind me now.

The Westroc product remained pliable for 45min to an hour depending on the viscosity of the mixture.

The instructions called for 3 parts product to 1 part water, I ultimately found 3 parts product to 2 parts water the best for plaque plastering.

I bent a small nail and tightened it into the collet of this really cheap dremel knock-off (Roto-Magic).

The idea was to have the tool shake/vibrate at 10,000 RPM and shake the bubbles up from within the plaster mixture when applied.

It worked like a charm, and I have to thank Bryce L. (an industrial arts student) who emailed me the idea.

You know you live in a hick-town when you can't find a reliable source of straws... There are lots of outlets for your typical thin drinking straws, but what I needed were 3/8ths to 1/2" slurpy/slushy straws, and after begging a couple of handfuls from the slurpy outlets in town I knew that this was not going to last long.

So I setup the fence on the band saw to rip down 40 or 50 1/2" square foam lengths from scrap material that I likely would have to just throw out regardless.

The router is chucked-up with a bit that has a 1/8" radius cutter and bearing tip to bevel off the sharp corners and improve the flow for the feeders (again based on info from Bryce)...

I believe that the straws were also somewhat denser than an equal length of foam. Since there tended to be much more distortion of the castings when using the straws.

The next round of castings will hopefully prove out this theory.

The foam feeder/sprues are actually easier to mount than the straws and are easily cut to exact angles with the new wire cutter.

Whether straws or small foam feeders any thing would be better than the 1" square feeders I had been using in the past.

There are 19 individual parts/plaques that are ready for casting now.

The far plaque in the back of this image is an 8" by 24" plaque that I've been sitting on all summer as it needs a custom flask to hold it.

I have a few ideas on how to make a series of flasks that will have dividers that can size a flask for large or multiple small pieces... yet to be made.

Tearing down a Briggs & Stratton engine is kinda fun, the first time... after 5 or more it's tedious and can suck the life right out of you.

Another project that has just jumped a notch on the list is a tilting furnace that I can lower an entire engine into, as this really is not fun anymore.

The engines are reduced to crucible sized chunks in a matter of an hour or so...

I still use the wood splitter on the tractor and know exactly how to place each part to break it up as efficiently as possible...

Occasionally a piece will let loose in an unpredictable fashion, and bounce off my chest, arms or whizz past my head... I always wear a heavy ABS plastic face guard.

This is just a BAD IDEA!!!

I have several heavy Aluminum rims that would yield over 100lbs of material, but I can't take this approach.

Crankcases, pistons and cylinder heads are far less ductile and tend to crumble and break cleanly with the wood splitter.

The rims on the other hand have a springy quality that makes them very dangerous when they slip on the splitter when under pressure.

I would guess that a 15" rim weighs between 25 and 30lbs but when let loose could break my arm, ribs or neck... The next option is to use a friends plasma cutter and par these down to manageable chunks, or make the the tilting furnace large enough to hold either rims or B&S motors.

This is what a full day of grunting and sweating gets you...

and it still has to be melted down to ingots before it can be used...

Inefficient...

Through the course of melting I was letting the pot come up to temperature, listening to the radio and gazing off into space when the furnace started to bellow lots of white smoke and white/yellow flames shot out of every opening and crack in the enclosure...

The pot shown here is slumped over on it's side and the Magnesium that was in the mix has all but burnt out...

Beyond loosing a relatively new melting pot (second one this year)...

The burner was nearly ruined as all the liquid Aluminum flowed in through the large air nozzle and settled into the base of the fan assembly.

That about killed the rest of this day, tearing down the burner and removing the metal and slag...

So as I enter day three, I only have 2/3rds of my scrap in ingots, and the burner still isn't working properly...

There is always tomorrow...

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