Steps for correctly starting an SLA run

Steps on Plastic maker

1. Get STLs to e:\users\... onto plasticmaker (there is a zip disk named "Sneaker-net" available for this).
2. Start 3DLightyear from the Programs menu
3. Load empty build platform (defaults are OK most of the time, except for this case)
4. Open STLs
5. Orient each part using the "Choose Triangle" tool to choose a triangle and and making it up or down facing.
6. Verify STL
7. Use "Automatic STL placement" to place parts or place them manually. Use orthogonal view to move parts.
8. If there are more than 10 parts, group parts into no more than 10 parts using the "Combine STLs" tool, otherwise proceed to step 11.
9. Unload parts.
10. Load combined STL file created from 2 steps back.
11. Modify each part style using "Modify Build Style". Works only when exactly one part is selected.
12. Build supports. 

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    Skip steps between lines if not creating a copy of the flies.
13. Load "Flytilt" files from Jeff's directory (both part file and the support file). Do not build supports for the fly.
14. Choose the files and modify the build style as follows:
• Set the "SFP comp" flag on.
• Set the "Auto Z calculate" flag off.
• Set "Z Correction" value to 0

• Prepare the files using the "Build" tool.
• Using the "list" tool, verify that no more than 10 parts are shown.

Steps on the SLA-250

1. Goto Utilities->Power Sequencer.
2. Turn Laser on.
3. Goto Utilities->Dos->Dos.
4. ftp to plasticmaker.
5. Use binary mode
6. Do *NOT* have interactive mode turned off with prom
7. Get files over. No need to change directories.
8. Exit DOS mode by typing exit.
9. Goto Utilities->Elevator Mover. Move elevator some 2 inches below the resin level.
10. Manually sweep under blades to see if there is junk sticking to it.

Important: Cover the sensors with the masks to protect them from the resin while examining the blade. Uncover the masks before shutting the door.
11. Goto Utilities->Elevator Mover and raise elevator so the resin just comes through the holes.
12. Sweep blade if necessary to remove bubbles.
13. Sit around for some time so 10-15 minutes elapse after switching on the laser.
14. Goto Build. Start Building.
15. If there is a "Resin level too low" message, try pushing the SLA machine gently till you hear repeated beeps. Ofcourse don't do this everytime. Once every 3 times or so, pour some more resin. After repeated beeps are heard once enough resin is added, first close the door and then press any key.
16. Wait around and see if the job starts properly. There is something wrong if the platform is raised too high above the resin level. The correct level is when the platform starts out with the resin just glinting off the top. If the platform doesn't start out properly, do the following:
1. Exit the current build. This is done by randomly pressing "x", "q", and "Ctrl-C" till a loud beep is heard and the program quits the current build.
2. Goto Utilities->Recoater Utility. Choose the "Modify build level" tool to set a new build level. Again the resin level should be such that resin level glints off the holes.
3. Restart the job

Notes:

• When to change the platform style: the platform style file mostly contains data for the height of each layer which is cured by the resin. If the parts are such that height wise resolution is not necessary (as when the parts are straight prisms) then a different platform file with increased recoating thickness etc, can be chosen. The default platform is for 62.5 microns. There are different style files which have layer heights as high as 250 microns.

• Please check the SLA machine frequently during a job.  Jobs can die in the middle of a run with the laser left on, which costs $10/hour for the pro-rated laser warranty.  A weekend stuck laser can waste over $500 of laser time.   Please arrange parts so they are as flat as possible. Each layer  takes approximately 1 minute, so the cost of fabrication is at least $100 per inch of height.

SLA (Stereo-Lithography Apparatus) Post-Processing
 

1.  At the end of a build, the platform will rise above the resin so excess resin drains from the parts.  Ensure laser indicator light is off.
2.  Prepare isopropanol and water rinses.  NB:  When not in use, cover isopropanol because it evaporates quickly.
3.  Prepare cart area for parts.
4.  Wearing nitrile gloves, cover calibration sensors to prevent accidental contamination by resin, then remove built parts, including supports, from platform.  NB:  If desired, first tilt up platform at an angle for 5 minutes so excess resin drains back into vat more easily.
5.  Remove supports from built structures, using a scalpel or other sharp instrument, if necessary.
6.  Clean parts first in isopropanol and then in water rinse.  In each liquid, rubbing and/or agitating the part helps.
7.  Repeat step 6 as many times as necessary to get the “squeaky-clean” feel.  Usually, a single repetition is usually sufficient.
8.  Use air hose to dry the parts.  To keep the air hose clean, it is usually easier to take the glove off the hand that is used to control it.  NB:  If drying after the water rinse, the part’s surface sometimes becomes translucent white.  If a more transparent finish is desired, it may be necessary to dry after the isopropanol rinse
9. Expose parts to UV in the PCA (Post-Curing Apparatus).  Number on dial roughly corresponds to number of hours that it is on.  Duration of exposure typically varies from 2-4 hours depending on part size (“flies” take only 2 hrs to cure).  NB:  Try to position parts closer to center of chamber, elevating them, if necessary, in order to achieve a uniform cure.  Too much exposure may cause discoloration.

Notes:

• Remove your parts in a timely manner.
•  If space exists on the platform, it would be appreciated if a squadron of souvenir “flies” is included and that the person initiating the build performs all the post-processing on them.
•  Confine contaminated tools to the cart and discard contaminated waste in the correspondingly labeled trash can.
•  PCA dial sometimes gets stuck so ensure that it is indeed properly counting down before leaving for the day.