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Appendix

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ACID NEUTRALIZATION (printmaking)

CHEMICAL SPLASH-RESISTANT GOGGLES, APRON AND GLOVES MUST BE WORN AT ALL TIMES IN THE ACID ROOM.

TO EMPTY THE ETCHING TRAYS:

• Turn on both exhaust fans.
• Add soda ash by sprinkling about 1/4 cup into tray. Allow bubbling to subside, and stir tray. Add another 1/4 cup soda ash, and allow bubbling to subside. Stir tray again and add another dose of 1/4 cup soda ash. (about 3/4 cup total).
• Test pH with test strip (throw used strip in garbage).
• If pH is between 6-8, (7 is neutral) then the tray can be emptied into the central tank.
• If the pH is 5 or lower, then add another 1/4 cup of soda ash, repeating as above. Test again. Continue with this procedure until the pH is between 6 and 8.

NOTES REGARDING THE CENTRAL TANK:

• When refilling the central tank, add 1/4 cup soda ash along with the water. This allows the tank to serve its function as a neutralization tank, stopping the action of the acid on the plate being dipped.
• Test pH in central tank weekly, not letting the pH drop below 9.

GAS KILN OPERATION (ceramics, car kilns)

USE ONLY IF TRAINED

Firing Process, Gas Car Kilns:

1. Firing is a two person job, so team up. E-mail kilntalk@stolaf.edu about firing intentions to keep other workers informed and to avoid conflicted use of space. If it is break or other unusual circumstance, e-mail publicsafety@stolaf.edu as well. On the chalkboard, note names, phone numbers and which kiln. Always use kiln logs.
2. Load kiln, using clean and kiln-washed shelves. Load as a team!
3. Set kiln packs and close peep holes.
4. Close kiln door. Remove all carts and obstacles and close door to room.
5. Close damper fully in winter for lighting (then open fully after about 10 minutes).
6. Open air valve 1 full turn and gas valve 1/2 turn. “Righty Tighty, Lefty Loosey”
   
7. Press Start
   
8. If kiln does not light with the clicking noise, press the two black reset buttons and try again.
9. If kiln does not light with repeated resetting, get a lighter and light by hand. Note this in log. Open damper fully about 10 minutes after lighting.
10. If candling overnight, start around 10 pm, then come early the next morning (8 or so) and turn up the air and/or gas. Come in every 30 minutes or so and check on the progress. Continue to turn up air and or gas as needed. Note in log and communicate with firing partner throughout firing process.
11. Let temp slowly climb to cone 06, about 1820*. Now it is time to reduce, to encourage nice glaze and clay body color. Heavy amounts of body reduction can lead to carbon coring. Please avoid excessive reduction.
12. Put kiln in reduction by closing damper about ¾, checking for flame caused by backpressure by removing peep holes. Flame should be 2-4 inches long and blue. Check flame frequently and adjust damper as needed to keep it in reduction. Close peep holes between checks.
13. Let climb to cone 1, about 2080*. Pull damper out to lessen reduction and encourage temperature to climb to cone 9, about 2300*. Check for falling cones, and note on log. Allow sufficient time for upper and lower cones to drop.
14. When cone 9 is down and 10 is soft, put kiln in heavy reduction for up to an hour. The flame should be 5-8 inches long and yellow, possibly with black smoke. Keep an eye on the temperature so that it does not exceed 2400*. It will likely slow down considerably or drop. This is ok.
    
    
15. Turn kiln off by pushing stop button and closing air and gas valves.
16. Open the kiln only when the temperature is below 250* and do not open a kiln if you did not fire the kiln.
17. Comment on the firing in the log and remove and store shelves and posts properly.

Important things to note:

• Sometimes it takes a long time. Be patient.
• Sometimes the temperature drops unexpectedly. Try adjusting the air or gas
• Sometimes it seems like the temperature just won’t climb. Try adjusting air or gas. Generally, adding more air makes things burn hotter.
• Keep clear, detailed notes, especially if something unexpected happened. Note how the firing turned out when you open the kiln.
• The team that fired is the team that opens the kiln. They need to assess how things went, learn where the hot and cold spots are, and note in the log accordingly.

Normal Signs:

• Heat
• Visible flame
• Louvered vent overhead opens when kiln is on

Signs that things are wrong:

• Extreme reduction smell or large amounts of black smoke coming from kiln or peeps. If this happens the kiln is in too heavy of a reduction.
• Yellow or red light in room is flashing: Leave the Room. Do Not Enter. This indicates carbon monoxide has built up. Call those on the emergency contact list.
• Strong scent of gas: if room appears normal, press stop button on back wall to cease any possible gas flow. Call for appropriate help.
• Sprinklers activated, building fire alarm activated: BE CAREFUL OF STEAM. Leave the room and make sure doors are shut. Wait outside for public safety and/or fire dept to show up.

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SCULPTURE DEPARTMENT WELDING GASES AND TANKS

IN CASE OF AN EMERGENCY, CALL 9-911. THEN CLOSE THE TANK VALVES ON THE ACET. TANKS, THEN SHUT DOWN THE WHOLE SYSTEM.

IN THE CASE OF A NON-EMERGENCY URGENT SITUATION AFTER HOURS, CALL X3281 AND SPEAK TO THE BOILER ROOM ENGINEER, WHO IS THERE AROUND THE CLOCK.

GENERAL INFO

The sculpture program at St. Olaf uses several welding gases.  We hold lifetime leases on the tanks – specifics are listed here: 

 

OXY ACET MANIFOLD SYSTEM

The oxy/acet. Manifold system tank rooms are located on the loading dock.  The key is on the tool room key chain.  The oxy. room is for storage of oxy tanks as well as all gases OTHER than acetylene.  The acet. room is for storage of acet. tanks only. 

The manifold system, which supplies the oxy/acet welding stations with gases, runs under a specific system that needs to be understood before attempting to turn on, shut off, or change out tanks. 

The acetylene manifold system has four large acet. tanks, all four of which are hooked up at once.  Two tanks, which are connected to the same line valve, should be labeled ‘in use’, and  the other two, also hooked up to one line valve, should be labeled ‘full’.  They should be labeled as such. The ‘in use’ tank valve and line valve should be open, the ‘full’ tank valve and line valve should be closed.

In the case of acetylene, we use two tanks at a time to maintain line pressure.  Both tanks drain at an equal rate, so empty at the same time.  When empty, follow tank change-over instructions carefully. 

The oxygen manifold system has two tanks, each hooked up to a separate line valve.  One tank should be labeled ‘in use’, and the other should be ‘full’. They should be labeled as such. The ‘in use’ tank valve and line valve should be open, the ‘full’ tank valve and line valve should be closed.

Once the ‘in use’ tank is drained, follow tank change-over instructions carefully. 

Turning on the System:

ONLY FOR THOSE TRAINED

OXYGEN:

• Locate the tanks labeled 'IN USE', and open the tank valve fully, slowly to start with.
• Open the main valve slowly, fully.
• Adjust the pressure adjusting screw so the line pressure reads about 100 PSI.

ACETYLENE:

• Locate the tanks labeled 'IN USE' and open slowly the tank valve about 1/2 turn only.
• Open the main valve slowly, fully.
• Adjust the pressure adjusting screw so the line pressure reads 12. This takes a while.
• Check in welding area to be sure no systems are left open (open yellow valves & listen).

Shutting Down the System:

ONLY FOR THOSE TRAINED

OXYGEN:

• Turn 'IN USE' tank valves off, but don’t over-tighten.
• Close main valve.

ACETYLENE:

• Turn ‘IN USE’ tank valves off, but don’t over-tighten.
• Bleed by pulling lever.
• Close main valve.

 

Tank Change-Over Instructions

ONLY FOR THOSE TRAINED

BASIC INFO:

• Remember to always open valves by ‘cracking’ them open first, pausing, then slowly open. 
• Open oxy tank valves fully.  Open acet tank valves only ½ turn.   In the case of an emergency, turn off the acet tank valve first, then close both main valves, then contact an authority to shut down the system (see list near phone). 
• Remember to never be harsh with the valves (ie: do not over-tighten in either direction)
• Any tank that is not hooked up should have its cap on. 
• Key to tank rooms is on the tool room key ring.
• Threads on gas systems are left-handed threads, to differentiate from oxygen, so turn them the opposite way than what is standard. 
• Never handle gas or oxy systems with grease or oil on hands, on tools, on rags, etc. 
• Diagnose which has run out, oxy or acet (oxy out=sooty flame, acet out=pops off).  Double-check this by reading the tank pressure valve inside the tank room, which should read 0. 

OXYGEN CHANGE-OVER:

1. Close main valve.
2. Close line valve, then tank valve on the tank marked ‘in use’.
3. Open tank valve for one marked ‘full’ (crack at first, pause, then open slowly, fully). 
4. Open line valve for tank marked ‘full’ (crack at first, pause, then open slowly, fully). 
5. Open main valve (crack at first, pause, then open slowly, fully).
6. Check that line pressure reads 100 psi.
7. Place the ‘in use’ sign on new tank, write M T in chalk on empty tank, hang ‘full’ sign on my office door and email me that the tank ran out so I know to order a new one. 

ACETYLENE CHANGE-OVER:

1. Turn off main valve.
2. Turn off line valve, then tank valves, on the tanks marked ‘in use’.
3. Turn on tank valves for ones marked ‘full’ (crack at first, pause, then open ½ turn only)
4. Turn on line valve for tanks marked ‘full’ (crack at first, pause, then open slowly, fully). 
5. Turn on main valve (crack at first, pause, then open slowly, fully).
6. Check that line pressure reads 12 psi.
7. Place the ‘in use’ signs on new tanks, write M T in chalk on empty tanks, hang ‘full’ signs on my office door and email me that the tanks ran out so I know to order new ones. 

 

REPLACING AN EMPTY TANK WITH A FULL ONE

1. Remove the cap from the new tank(s) just before hooking them up. 
2. Double check that the line valves for the MT tank(s) is turned off. 
3. Using an open-ended wrench, carefully loosen the nut from the MT tank being careful to not strip the sides of the brass nut.  Remember that gas threads turn the opposite direction because they are left-handed.
4. Cap the empty tank. 
5. Connect the fitting to the new tanks and carefully thread the nut in place, being careful to not cross-thread. 
6. Tighten (but don’t over-tighten) the nut. 
7. If the new tank, or set of tanks, will be put to use immediately, then open the line valve and then the tank valve as described above

 

OTHER WELDERS AND TANKS

Tanks used with portable welders (mig, tig, and portable oxy acet) are stored in the manifold system tank rooms on the loading dock.  Only acetylene tanks are stored in the acetylene tank room; all other gases are stored in the oxygen tank room. 

Tanks must be labeled as either ‘Full’ using a hanging sign, or as ‘MT’ (written in chalk) to indicate the tank is empty.  Follow directions on the tank change-over instructions carefully. 

 

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AUTOCLAVE OPERATION (sculpture)

USE ONLY IF TRAINED

Note: to preheat, run through a cycle first with chamber empty.  This first cycle will take about 45 minutes.

To operate:

• Make sure the autoclave is plugged in.
• Load the sterilizer.  No more than 3 small to medium molds per load.  Load with cups down, use a dbl tray, nothing hanging over edge of trays. 
• Close and lock door by turning wheel to the right, just until snug – do not overtighten.
• Set timer to desired time.  20 minutes should work fine.
• Turn on (white toggle switch). Red light on toggle switch indicates steam is entering chamber.

During operation:

• The chamber builds up pressure and warms.  The timer starts when the chamber reaches temp.
• White light (Sven) indicates sterilizing temperature has been reached and the timer is running.
• Yellow/Orange light (Ole) indicates timer is done and autoclave is exhausting steam.

Finally:

• DO NOT open chamber until gauge reaches zero.
• When chamber pressure gauge reaches zero, the cycle is complete.
• Wear eye protection, apron, and gloves.
• Turn door handle to the left, which will break the seal.
• Open slowly at first to release the steam, then open fully.  Keep face back from escaping steam.
• Remove molds carefully, and collect melted wax in the manner you have been taught, being careful to not spill onto the floor of the sterilizing chamber, which will clog the drain completely. 
• Begin the next load if continuing. 
• If not continuing, leave door ajar for a bit to allow water on chamber floor to evaporate.

Troubleshooting and Maintenance:

• Keep the gasket and the area around the door clean, using a green scotchbrite scrubby if needed.
• Keep liquid wax contained in trays.
• If water comes out when opening the door, crank the door shut immediately and contact prof. or tech.

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WAX BURNER OPERATION (sculpture)

USE ONLY IF TRAINED

1. Turn on the ventilation system labeled ‘mold making’. 
2. Open gas shut-off valve (yellow ball valve) leading to the wax burner. 
3. Be sure burner control knobs are in the off position (located on the right end of stove.)
4. Press and hold red button on front of safety panel.  Continue to hold this button through step 7.
5. Wait 10 seconds, then light BOTH pilots using a striker.
6. While still holding red button, press and latch BOTH pilot safety switches - the red and silver buttons on top of the safety panel.  Hold all three buttons for 15-20 seconds. 
7. Release all three red buttons.  Pilots should now stay lit. 
8. Slowly open the burner control valves(s) and adjust to desired heat.

NOTE: Both pilot lights MUST be lit in order for either burner to light.

To turn off system:  Turn off burner control knobs, and close gas shut-off valve (yellow ball valve).  It’s ok to leave pilots burning if you will be using the burner again soon, but turn off system totally when you are finished working.  Remember to turn off the ventilation when you are finished with wax working. 

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PORTABLE KILN (sculpture)

USE ONLY IF TRAINED

Light up procedure:

1. Lower lid so kiln is not top heavy.
2. Move kiln using pallet jack. Set beyond 1st crack in concrete, Westerly on patio.
3. Remove pallet jack.
4. Raise lid of kiln.
5. Connect gas in building with quick-connect.
6. Blue valve on kiln must be off. (This is the main burner valve.)
7. The pin valve is a fine tuning adjustment that should not be adjusted, in most cases. If the kiln will not light, check to see if this valve has been fully (improperly) tightened.
8. Open (yellow) ball valve in building.
9. Open (yellow) ball valve on kiln.
10. Hold down red safety button and light pilot. Hold until flame stays, about one minute.
11. Ready to light: open (blue) main valve on kiln slowly.

Shut down procedure:

1. Close (blue) main valve on kiln.
2. Close (yellow) ball valve on kiln.
3. Close (yellow) ball valve in building.
4. Disconnect kiln from the gas (at quick-connect in building)
5. After the kiln has cooled, move inside with the lid down, using the pallet jack.
   

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RAKU KILN (ceramics)

USE ONLY IF TRAINED. UNDER NO CIRCUMSTANCE SHOULD THE RAKU KILN STAY OUTSIDE OVERNIGHT OR IN INCLEMENT WEATHER.

Light up procedure:

1. Lower lid so kiln is not top heavy.
2. Move kiln to patio and raise legs so the kiln is not able to roll.
3. Raise lid of kiln. You may load the kiln now, but leave the lid up.
4. Connect kiln to gas with quick-connect (in shed).
5. Main burner valve on kiln must be off. (This is the small blue valve, which is inside the box.)
6. The pin valve is a fine tuning adjustment that should not be adjusted, in most cases. If the kiln will not light, check to see if this valve has been fully (improperly) tightened.
7. Open orange knob (over behind salt kiln) one full turn (to left).
8. Open blue valve near quick-connect in shed.
9. Open blue valve on kiln near the gas connect (outside the box).
10. Hold down red safety button and light pilot. Hold until flame stays, about one minute.
11. Ready to light: Slowly open main burner valve (small blue one inside the box) on kiln.
12. Lower the lid.

Shut down procedure:

1. Close main burner valve on kiln (blue one in box).
2. Close blue valve on kiln near gas connection.
3. Close blue valve in shed near quick-connect.
4. Close orange valve behind salt kiln (turn to right)
5. Disconnect kiln from the gas at quick-connect.
6. After the kiln has cooled, move inside with the lid down.
7. Return any gear or equipment you have borrowed from foundry.

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GAMSOL

• Gamsol is the only mineral spirit or paint thinner allowed in Dittmann Center.
• Gamsol is a highly purified form of odorless mineral spirit, distilled at high temperature and purified of all aromatic components.
• Gamsol is made by Robert Gamblin.
• Gamsol is easily recycled and reused, which is a benefit both environmentally and financially.
• To Recycle Gamsol: Once you have used a small amount of Gamsol to clean your brush, pour that amount into the large settling jar, kept in the flammable cabinet. A funnel is available if needed. If sludge remains in your jar, mix it with a small amount of Gamsol from the settling jar, swish, and return to the settling jar. The goal is to get all used Gamsol AND paint sludge into the settling jar so that no sludge makes its way into the trash. Occasionally, after being allowed to settle, the top clear layer in the settling jar may be poured into the metal Gamsol tin (also stored in the flammable cabinet) for re-use.

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PATINA BASICS (sculpture)

Prep

• Clean the metal thoroughly using the sandblaster, then handle only with gloves. Set on clean, non-metal surface (fire brick). Work at the foundry sink.
• All of the following methods are for “cold” applications, so a torch is not needed. However, warming metal with a heat gun helps just before applying patina products. The heat gun is kept in the tool room.

Liquid Patinas

• Wear personal protective gear: chemical resist gloves (the aqua colored ones), vented chemical splash-resist goggles, apron and protective clothing. 
• Pour liquid patina into a small cup, taking only what you think you will need. Start with a small amount, taking more only as needed. Don’t pour used patina back into the jug.
• Use brush or sponge for application, then clean it with water for re-use.
• Apply patina in thin coats, allowing it to dry between coats. Thick coats will tend to flake off. Avoid pools and drips. Reapply if needed for desired effect. Some patinas will take several hours to fully react to the metal.
• Layers of different patinas may be used for a desired effect. Let each coat dry before applying next coat.
• Note that Antique Black is intended for use with bronze and copper, while Presto Black is intended for use with steel and iron, both resulting in a black-colored surface. Using the Presto Black on bronze will result in a brown-ish color.
• When you have reached your desired effect, seal the piece to stop the reaction of the patina and to seal out moisture and oxygen. See below.

Powdered Minerals

• Powdered minerals may be applied alone, or over a dried patina, or over a wax – either as it dries or after it has dried.
• Avoid breathing dust, work at a slot vent, clean up dust properly.

Patina Waxes

• Shake or stir these waxes before use. Be careful – they are thin and messy!
• They may be used alone as a colorant and sealer, or may be used over a (already dry) patina, or may be used over the shellac sealer. They may adhere best if applied over Johnson’s paste wax.
• Patina waxes may be applied with a brush or sponge, using a stippling action to avoid brush strokes.
• Allow these colored waxes to dry for about 1 hour, then buff with a soft cloth. They become extremely hard when dry, in which case they will be impossible to buff. Keep an eye on them while drying.
• Wipe the jar clean before sealing and putting away.

Misc. Patina Methods

• Some common chemicals or processes can make an interesting patina.  Some are listed below.  See the prof. for more information.
• Ammonia fume
• Heat (flame)
• Oil paints
• Acrylic paints

Sealing

• Sealing your piece as a final step is optional if it is not an outdoor piece, but still a good idea, especially to keep the patina effect from changing over time. You may use a sealer such as shellac or Young’s water based sealer. Both should be sprayed on. (Use the sculpture spray booth). Wax may be used as a final coat alone, or on top of the sealers listed above. Never try to apply a sealer over wax. Johnson’s paste wax works well, as does the colored waxes mentioned above. Both must be buffed just before drying, the colored waxes about one hour, the Johnson’s paste wax a bit sooner.

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SANDBLASTER (sculpture)

• The sandblaster is not filled with sand as its name implies. Never use sand in this tool. The standard blasting material we use is Alundrum, also known as aluminum oxide, 60#.
• Once you have placed your sculpture inside the booth (through the door on the right side) make sure the door and the main part of the hood are securely closed.
• The switch on top of the booth turns on the light as well as the dust collector. Do this before stepping on the foot pedal.
• With your hands inside the gloves, pick up the spray nozzle in your right hand and the metal in your left hand. Stepping on the foot pedal will start the flow of grit. Aim grit only at the piece to be blasted, not at the glove, and not at the window.
• The grit is recycled through the bottom of the hopper, and may be poured from the bucket back into the booth through the screen which filters out any chunks. Eventually the blasting material will become rounded and less effective, at which point it must be disposed of. See the Prof. or Technician for proper disposal technique.
• The dust collector filters need to be 'stirred' about once a week, and this is done by turning the crank on dust collector

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SALT KILN RECIPES (ceramics)

To coat the soft brick (door of kiln):

Initial coating for new soft brick:

• 1 Part Ball Clay
• 1 Part EPK

Subsequent coatings:

• 50 Alumina Hydrate
• 50 EPK
• 1% Epsom Salts

Make sure that the surface has been scraped down well, cleaned with a damp sponge, and allowed to dry before coating the inside of the door. Make a thin slurry (consistency of heavy cream) and paint on all the soft brick surfaces, like the inside of the door and edges of the door. This only needs to be done once in a great while, but should make the soft brick last longer.

To coat the hard brick inside:

• 65 % potash feldspar
• 25% kaolin
• 10% whiting

Coat hard brick to create a glaze. If this chips off over time, scrape away loose parts and coat that area again before firing.

Recipes for firing:

Kiln Wash
50 Alumina Hydrate
50 EPK
1% Epsom Salts

Wadding
2 parts EPK
1 Part Alumina Hydrate
½% Bentonite

Soda Solution
1.5 to 2 lbs of Soda Ash
1 Gallon of Hot Water

Whisk the water and soda ash together. Allow the soda Ash to soak for about 30 minutes then whisk again. Add the solution to the bucket and portable tank sprayer bucket. Make sure that you stir the solution prior to each round of soda induction.

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