FirstAuraGoggles

Aura Goggle Recipe #1

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This describes the construction of a working pair of aura goggles, including reasonably detailed assembly instructions, and a parts and suppliers list.

Aura Goggle Recipe	#1
Goggle Type	Liquid Lens
Active Agent	Pinacyanol Bromide
Solvent	Methanol
Lens Color	Deep orange red with pink highlights

A working pair of aura goggles can be made if the following principles are followed:

• Extraneous light must be excluded, so that only light which shines through the aura goggle lens reaches the wearer's eye.
• The viewed light level must be reduced about nine (9) photographic stops, so that the wearer's eye and brain is placed into a low-light condition.
• The right colors are obtained in the aura goggle filters by use of the right dyes, filters, and solvents.
• Additional details are given here.

The dye density specified here is calibrated for a dye light path length of 10mm, which matches the Starna spectrophotometry cell. The 50mm spectro cell width gives a good match to the inexpensive welding goggles.

Parts List

• Hobart 770096 Oxy-Acetylene Goggle - 50mm Eye Cup
  • 50mm replaceable lenses
    • Quantity: 1
    • Cost: $11.99 / pair
• Black drafting tape
  • Dick Blick Art Products
    • 1/2" wide, enough tape to fix cells to front of goggle frame, and block extraneous light.
    • $9.83
• Starna 35-px-10 Spectrophotometry Cells
  • 50mm x 10mm
  • circular, optical plexiglass, large irradiated area, nominal vol. 17ml
    • Quantity: 2
    • Cost: 2x $140 = $280 / 2 cells
• Methyl alcohol
  • Reagent Grade, 99.8% purity
    • Quantity: 2 x 17ml + 1ml = 2 x 18ml = 36ml
    • Cost: $14.95 / 16oz,
• Pinacyanol bromide
  • 3.33mg / ml methyl alcohol
    • Quantity: 120 mg
    • Cost $45 / g * .180 = $5.40
    • Requires constant refrigeration

Density of Active Ingredient

• Pinacyanol bromide
  • 3.33mg / ml methyl alcohol
    • Total quantity: 120 mg
      • 56.6 mg is used in each lens
      • 113 mg used in both lenses
      • 7 mg remains in the 2ml leftover dye fluid
  • This density over 10mm path length gives
    • Adsorption of approximately 2.70A, 99.8%
    • Reduction of light intensity by
      • 9 photographic stops
      • factor of .00195

Incidental Equipment

• Small refrigerator to keep dye cold at 0 - 5 deg C
  • The total lifetime of the dye in solution is unknown.
  • Refrigeration of the completed lenses when not in use is recommended
• Chemical scale to weigh out dye
  • Sensitivity to .001 gram is best, but .01 gram will do, and is much less expensive
  • weighing boat or papers
• Small stainless steel scoop to manipulate dye
• Graduated cylinders large enough to measure solvent
  • 25ml adequate
• eyedropper to transfer dye solution
  • 2 - 3 ml adequate
• Flask & cork to mix dye
  • 125ml adequate
• Glass rod to mill dye powder, and mix dye solution
• Funnel and stand to aid in filling spectro cells
• Gossen Luna-pro or equivalent light meter to measure transmitted light
• Standard safety gear
  • safety goggles
  • vinyl apron
  • nitrile rubber gloves

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Procedure

Aura Lens Creation

• Don all safety equipment.
• Prepare two 35-px-10 spectrophotometry cells to receive the dyed methanol (unpack & clean them, etc.)
• Measure 36ml of methanol
  • Measure 18ml of methanol into a graduated cylinder.
  • Add to clean flask
  • Repeat previous two steps for a total of 36ml methanol in the flask.
• Measure 120mg of pinacyanol bromide onto a weighing paper.
• Mill pinacyanol gently with glass rod to ensure that all lumps are reduced to granules.
• Pour the pinacyanol into the methanol flask. Tap the paper, and scrape with the scoop to encourage as much of the dye to enter the flask as possible. Stopper.
• Shake vigorously for a minute or two until the dye is solved.
  • If the dye doesn't solve, now is a good time to panic.
• Set the flask aside to rest for a minute.
  • This will allow any small suspended particles to settle.
• Fill the spectrophotometry cells
  • Pick up one of the spectrophotometry cells, and carefully remove the PTFE stopper. Put the stopper top down in a spill pan or on a clean work surface.
  • Using a pipette or eyedropper, carefully transfer approx. 17 ml of pinacyanol dye solution from the methanol flask to the spectrophotometry cell. Do not fill beyond the beginning of the fill neck.
  • Carefully replace the PTFE stopper into the spectrophotometry cell. Try to obtain a good seal.
  • Wipe the outside of the cell, including the fill neck and stopper, with a paper towel and 91% isopropol / ethyl (rubbing) alcohol to remove any traces of dye.
  • Place the completed cell so that the neck remains upright.
  • Repeat above steps for the second cell.

After filling is complete the two new aura lenses can be attached to the welding goggles in place of the original welding filters to create the complete aura goggles.