My Aluminizing System

 

 

 

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Well there it is, not particularly pretty, but it works and its portable J  Below is a list of possibly interesting  aspects of my system.

 

  1. Chamber was an unused Propane cylinder for a BBQ grill
  2. Cold trap is Freon based, and uses a salvaged refrigerator compressor and R22 Freon.
  3. Rough pump is a donated HVAC service pump
  4. System incorporates a Glow Discharge cleaning system, built from a pair of automotive spark plugs and neon sign transformer
  5. Time from sealing chamber to evaporating Al, 12 minutes J
  6. Only consumable items are 110Vac, Water, Reynolds Wrap Al foil, and a bit of tungsten every now and then.
  7. To date, I’ve got about $850us invested in the whole setup, but lets not talk about the amount of TIME invested J

 

 

Here’s a short list of things I need to do still.

 

  1. Optimize the Tungsten heating element design.
  2. Finish the heating element controller
  3. Add a Shutter to protect mirror surface from blobs of molten AL falling on them during initial startup
  4. and finally, Build a Larger Chamber J

 

To date, I’ve ran a bunch of test pieces through, a 5” mirror, and a 10” mirror, all with good results, and only one catastrophe.  The bad part is, the one catastrophe over shadows all the good results up till now L  What happened was as I heated the tungsten filament, a blob of aluminum fell off the heater, and landed on the mirror surface.  At  first I didn’t think much of it, as it looked just like a what happens when a blob of plumbing solder lands on a cold surface.  Unfortunately the aluminum was MUCH to hot for the Pyrex mirror to handle, and a pit about a ¼” in diameter and 0.015” deep formed.  The worse part is, the blob of aluminum didn’t land in the center of the mirror, but about 3 inches from the edge (still not certain how it landed so far from the center.)  Today I learned a valuable lesson, either pre-melt the aluminum in an empty chamber OR install a shutter to prevent this from happening!  Going from a finished mirror back to 80 grit is not something I ever want to have happen again!

 

Here’s a picture of a recent test item to at least show the thing works J

 

 

That’s it for the moment, still bummed about damaging a mirror, but  I did  learn a lesson, worse part is I had been warned about just such a thing happening!  Sigh…

 

Anyway, check out some of the sub links on the left if you are interested in seeing just exactly how I got to this point.

 

Take Care,

James Lerch

Jlerch1@tampabay.rr.com