This page contains procedures for regular maintenance tasks around the shop. These are designed to be references, not instructions. Do not attempt to perform these tasks without training with Paul first.

Main Shop


Unjamming pneumatic tool changer

If the pneumatic tool changer is not working, first make sure the spindle is raised all the way. If not, then get a step stool, imperial hex key set, and brass hammer. Standing on top of the stool, unscrew the three machine screws holding the pneumatic tool changer in place. Be careful to keep track of the washers. If one falls into the top of the mill, mark the machine out of order and submit a broken tool form.

Once the tool changer is loose, set it gently on the mill table. Try unthreading the draw rod. If it is already loose, rethread into the collet three turns. If it is too tight, use a wrench to loosen it. Set the tool catcher underneath the collet on the mill table, then tap the top of the draw rod with the brass hammer. Once the tool has fallen out of the collet, unscrew the draw rod and remove the collet. Then reset the pneumatic tool changer and test it.

Realigning the vise

If a student has removed a mill vise, it is necessary to indicate the vise back to square with the axes of the mill. Get the indicators from the purple tool box under the cabinet behind the proctor desk. Put the indicator arm in a collet, then attach the indicator such that the pointer is within 15 degrees of vertical along the back edge of the vise. Tighten one side of the vise so that the vise can still pivot. Then jog the mill back and forth and watch the change on the dial. Tap the vise with the brass hammer until jogging the mill doesn't affect the dial.

Checking head tilt and nod

The mill table and ball screws are lubricated by a pump. Refill the pump reservoir with Mobil Vactra No. 2. Fill the oil cups on the mill head and spindle with SAE 30W oil. Simply add oil until the cup is full, and then wait for it to percolate to the spindle. Lastly, there is a Zerk fitting on the back of the mill head. Use the manual grease gun to refill it.


Changing compound angle

Loosen the two bolts on the circular plate between the lathe ways and the tool holder. Rotate the plate, reading the angle on the side. Alternate between bolts while tightening until it is secure. Then loosen the tool post, either using the hex key at the lathe station or a combination wrench. With no tool in the post and no collet in the chuck, rotate the post and press it gently to the collet until it is flush. Retighten the tool post, careful not to change the angle of the post.

Setting tool holder heights

Find one of the center height gauges from the red tool cabinet or lathe stations. Put a center in the tailstock of the lathe and bring it close to the apron of the lathe. Align the pointer on the gauge to the center, and then move the gauge over to the tip of the tool. Using a hex key, raise or lower the tool holder until the two align. Lock the tool holder in the post to make sure it still matches.

Replacing tools and inserts

For high speed steel bits, loosen the set screws holding the tool in place. Before replacing the tool, make sure there are no chips or grease in the tool holder. Be careful not to over extend the tool. When you are done, reset the tool height.

For carbide inserts, loosen the hex screw on the clamp. Once the clamp can swing out of the way, remove the insert, but leave the seat below it. Either flip the insert around to use the other point, or replace it. Again, make sure there are no chips under the insert.

Changing chucks

Take the square wrench from the yellow tool boxes by the lathe stations. Loosen the three cams on the chuck and align them all vertically. If the chuck doesn't come off easily, tap it with a lead hammer. Take the new chuck and make sure there are no chips on either its mating face or the mating face on the lathe. Slide it onto the cams and twist them all back into position. Ensure that they are all tight, and get someone else to check. Return the collet chuck when cleaning up.


The lathes are lubricated four ways. Firstly, there is the apron - unscrew the cap on the left hand side of the apron and fill the reservoir with Mobil Vactra No. 2. Check the level gauge on the side of the apron to see if it needs oil. To lubricate the headstock and gearbox, remove the back panel of the lathe. The headstock inlet is on the upper left, and the gearbox inlet is on the bottom right behind a gear. For the headstock, check the gauge underneath the chuck on the front of the lathe, and fill it with Mobil DTE24. For the gearbox, check the gauge underneath the feed rate settings and fill it with Mobil DTE Extra Heavy. After they are filled and re-capped, close the panel and reset the interlock. There are also Zerk fittings on the apron and tailstock - these are filled with the manual grease gun.

Sheet Metal Shop

Cleaning files

Whenever the files are used, chips build up in the grooves, eventually dulling them. Take the wire brush and run it along the grooves to get the chips out.

Replacing sandblaster screen
CNC lathe lubrication
Adjusting pan break

Wood Shop

Changing router bits

The router table can hold many different bits for different cutting patterns. To change it, unplug the router and take the fence off the table. Drop the router by loosening the clamp on the side of the router. Take two wrenches to loosen the collet and remove the bit. Put the new bit in its place and work in reverse, tightening the collet and raising the tool. Reset the bit after finishing.

Removing table saw guards

Turn off the saw and lock it out. Slide the red table insert out of the table with the metal hook. Loosen the lever next to the riving knife and lift out the guard. To replace it, push the kickback pawl (the ratcheted teeth) up while re-inserting the riving knife. Tighten down the lever, slide the red table insert back into place, and then release the pawls.

Changing bandsaw blades

Unplug the saw before opening both top and bottom cabinets. Take the blade guard off with a screwdriver. Lower the top guide wheel with the handle on the back. Remove the table insert and carefully slide the blade around the guides underneath and then out the gap in the table. Curl up the blade and hang it by the wooden cabinet. Carefully uncurl the new blade with gloves, and slide it back into the saw. Make sure the teeth are pointing in the right direction. Re-tension the blade using the handle behind the top wheel. Reattach the blade guard.

Rapid Development Lab

Changing 3D printer filament
Unclogging extruder
Auto-leveling of 3D printer not working

Make sure the tip of the extruder can make electrical contact with the four corners of the bed. Clear any plastic off of the extruder by sanding or filing it if necessary. Remove the bed and clean the corners. Use a steel brush to clean the grounding wire on the extruder head, and ensure the screws on the bed and nozzle are fully tightened.

Troubleshooting laser cutter

If the computer is sending multiple pages to the cutter, or it is only cutting part of the file, make sure that the page dimensions in the software match the cutting area dimensions on the laser cutter print menu. Then check that the normal print menu still says print "plate area" instead of "entire area".

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