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Behind the garden by the main door is a large storage shed. The door to the shed is not locked, so anyone can access it when they need too. Please use caution, as bees and wasps have been known to use this area to build their nests here.

When running the compressed air on a humid day, a lot of moisture builds up inside the air tank. If left unattended, this moisture will rust a hole though the holding tank causing the compressor to fail. Replacement for compressed air units of this capacity run upwards of $3,000-$7,000 (2016 prices). Needless to say, if this unit fails it will be a bit before NPL can absorb that sort of expense!

To drain the holding tank, just turn the handle to the 'open' position. Leave it open until moisture stops rushing out, then close it all the way . Leaving the drainage pipe open will result in insufficient pressure to run air scribes or abrasion units. If you notice very low pressure, or if you hear the compressor constantly running, please go check the drainage pipe.

Air scribes, more than any other tool in the prep lab, are prone to getting 'gunked up' beyond all belief. Trapped bits of matrix mix with pneumatic tool oil to create a perfect sludge for eroding bushings, pitting O rings and wreaking havoc on the precise movements of the stylus. To avoid such issues, it become necessary to field strip and clean the scribes from time to time. As NPL does not currently use the scribes on a regular basis, a maintenance schedule is not required.

In lieu of a schedule, here are some guidelines for when to clean the Air Scribe you are using:

• normal cleaning once a month if you use it often.
  • if you are using the tool daily, please do this weekly.
• when you finish the project and put the scribe away for good.
• when using a tool for the first time, take it apart just to make sure it was cleaned by the last person using it

To field strip the PaleoTools scribe units you'll need: a towel, a pair of pliers, some small containers (for keeping all the parts from rolling on the ground), a selection of lint free rags, silicon lubricant, and pneumatic tool oil.

ALWAYS MAKE SURE YOU ARE DISCONNECTED FROM THE AIR HOSE BEFORE PROCEEDING

Here are general instructions. For more detailed procedures and tool schematics please see the literature that came with the equipment, or go to the JSG-NPL shared drive and look in DocLib/Manuals-equipment/AirScribes.

• Lay out a terrycloth towel as your work space. Put a collection of containers close at hand for keeping small parts from getting lost.
• Unscrew the head and take the piston out of the head.
  • This can be done by hand, unless the tool is really dirty. If you need to use the pliers, drape a cloth over the tool head- this will keep the jaws of the pliers from scraping the tool.
• Remove the spring, and place it in a container.
• Wipe the shank down with a lint free cloth and oil it LIGHTLY.
• The o-ring should be wiped clean and lubricated slightly with silicon lubricant. This is kept in a round plastic container in the Prep Tool tool box.
• Inspect each element before reassembling the unit. Look for cracks or pits on the O ring, stiffening of the spring, misshapen of opening in the bushing and any signs of rust or pitting along the body.
• Once the unit is reassembled, make sure it works before putting it away.
• CLEAN AND PUT AWAY ALL TOOLS, CONTAINERS AND TOWELS.

More detailed account of taking care of air scribes can be found here.

First, when cleaning the air abrasion unit, take a non-ammonia glass cleaner (there's a small bottle in the cabinet under the fume hood) and wipe down the lid. The literature that came with the unit does a good job of covering the routine maintenance.

Emergency replacement parts (extra quick release valves, additional air hose, etc) are located behind the unit, tied to the area near the shop air intake valve.