Epilog Laser

From ProtoLab Wiki
Revision as of 03:00, 30 August 2019 by Alukens (talk | contribs) (Preparing a File)
Epilog Laser in the Idea Shop Prototyping Lab

About


The epilog laser is a machine that is capable of cutting, rastering, and etching a variety of materials in a quick and easy way. The laser is limited to performing these actions in the 2D X-Y plane. This machine uses files printed from AutoCad to cut these parts, and files can be sent from any shop computer in the lab.

General Stats:
Material : Acrylic, Wood, Vinyl, Foam Core, MDF, ABS, Paper, Card Board, Leather. (See Laser Cutter Materials for what isn't allowed.)
Maximum Part Size : 457.2mm x 609.6mm (18in x 24in)

Strengths and Weaknesses

Main Article : Strengths and Weaknesses

The Epilog Laser Cutter excels at inexpensively and quickly cutting 2D geometry out of a variety of materials. It should usually be the first machine to consider when thinking about how to create a prototype. Even though the laser can only cut 2D geometries, it can still create 3D parts either by using acrylic solvent to bind acrylic or creating parts that fit into each other. However, if one solid part needs to have depth or 3D aspects, the laser cannot be used. Also, the laser is restricted to the 18" x 24" bed, as compared to 48" x 96" bed size of the ShopSabre. It is very simple to create files to cut in AutoCade, and they can quickly be sent to the laser computer and cut. However, there are oftentimes a long queue to use the laser, and during these times each slot in the queue is 1 hour long, so it can quickly add up into very long wait.

Using the Epilog Laser Cutter


Main Article : Using the Epilog Laser

Before cutting the part you sent to the laser cutter, make sure the air compressor is turned on in order to reduce the amount of fumes and smoke coming from the material as it is cut. You should see the name of your job on the screen of the laser cut. Do not press go until the data LED has stopped blinking, if it is still blinking this means the laser is still receiving data on your file from the computer. Once you are ready, press the green go button and the laser will begin to cut your part. While the laser is cutting, the door of the laser must remain closed, otherwise the job will be stopped. If at any time you want to pause the job, press the red stop button. Press the green go button to resume the job. If you want to end the job, press the reset button. Once a job has finished, the laser will home and beep, then it is safe to remove the material. IF the laser has not cut all the way through the material, depending on the material, it may be easier to cut it out with an x-acto knife. If you wish to try to use the laser to cut it out, place the material back in the bed as close to the original position as you can, and run the job again. If before a job you are confident the laser will not cut all the way through on the first pass, set the material in the Epilog program to be thicker than the material you are actually cutting.

Preparing a File

The Layers Menu in the AutoCad Epilog Laser Template

All of the computers in the shop have either AutoCad 2017 or 2020 software and can be used to create files that will be laser cut. In AutoCad, your file should only consist of 2D geometry and should use the preset layering system the shop has in place (Template stored at Z:/APP SUPPORT/ACAD/epilog laser.dwt). The AutoCad Layer menu is pictured to the right.

The "CUT_FIRST" layer (Yellow) is used for lines that will be cut first, while "CUT_LAST" (Purple) is for lines that will be cut second. "RASTER" (Red) is for rastering, while "SCORE_SHALLOW" (Green) and "SCORE_DEEP" (Blue) are for scoring shallow and deep respectively. By default, the "0" layer is used. If there are features that you would like to be ignored by the laser cutter, they should be selected and moved to the "LAYOUT" (White) layer. Features left in the "0" layer will be cut!

Once the drawing is complete, it should be placed inside the laser bed template on one of the computers. No part of the drawing should go outside of the 18in x 24in laser bed. The width of the material cut by the laser is very small, so features can be placed within 1/16in of each other in order to reduce the waste of material. Double check your drawing making sure to delete all duplicate lines, points, and other unnecessary segments or move them to the "LAYOUT" layer. This step will produce cleaner cuts and a better finished product. Once you believe your file is ready to send to the computer, call over a shop supervisor to take one last look at it before it is sent.



Sending a File to the Laser

Main Article : Sending a File to the Laser
How your print screen should look before sending a file to the laser

To send a file to the laser, click the print icon at the top of the program. The page that appears next should match the screen pictured to the right. If it does not, change the appropriate settings so that it does. Once the settings are correct, select window, as circled in the example screenshot. Selecting window will bring you back to the drawing screen. From here, select the top left corner, and the bottom right corner of the entire bed you are going to cut. Do not just select the part you are going to cut, select the entire 18" x 24" bed. Once this is selected, make sure that plot scale ratio is 1:1, select print preview. If everything looks correct with the cut, including all of the geometry being set to the correct color layer. After double checking the preview, select print. This will send the file to the computer by the laser cutter.

Prepping the Laser

Once, your file is sent to the laser computer, have a staff member walk over to the computer with you to begin cutting. Place your material into the laser bed. IF you are using acrylic, peel off one side of the protective paper. The Epilog Job Manager application should be open on the computer, if it is not, open it. Under the jobs tab, select the job you want to print. Once a job is selected, a screen detailing the specifics of the job will be shown. From here, select the material you will be cutting from the material tab in the bottom left corner of the screen. Usually, this is all that needs to be done for an average job. If your material is not listed, enter the settings if you have them under the colors tab. The laser must then be manually focused.

Manually Focusing the Laser

Main Article : Focusing the Laser

The Epilog Laser Cutter automatically focuses itself depending on the material being used. For extremely precise cuts, it may be safest to manually focus the laser. To manually focus, use the triangular focus tool stored near the machine and press the "Focus" button on the cutter. Place the tool on the laser and use the arrow buttons to raise the bed until the tool and material just barely touch. Once you are satisfied with this, remove the tool and make sure that auto-focus is disabled in the Epilog Job Manager (and resend your file to the cutter if necessary). Then press "Go" to begin your cut!

Machine Proficiency


In order for an individual to advance in machine proficiency they must demonstrate ability to perform certain actions or tasks. All levels include abilities and concepts from lower levels.

This section is primarily for student workers.

Level 0

Individual has demonstrated they are capable of:

  • Plotting a prepared AutoCAD vector / hatch raster file to Epilog Job Manager.
  • Selecting the correct material in Epilog Job Manager.
  • Determining whether manual or auto focus should be used.
  • Determining whether the exhaust fan and air assist compressor are operating.
  • Locating the fire retardant cloth and fire extinguisher.

Individual understands the concepts:

  • What materials are unsafe to cut or engrave on the laser.
  • Adjusting power and speed settings to cut slightly different material.
  • Application of cut first versus cut last and scoring versus rastering.


Level 1

Individual has demonstrated they are capable of:

  • Preparing a vector / hatch raster AutoCAD file for laser cutting.
  • Manually focusing the laser.
  • Identifying materials that are safe to cut / engrave.
  • Clean the accessible mirrors and lens.
  • Recovering from an auto focus bed crash.
  • Replacing and cleaning the laser bed.
  • Adjust power and speed settings to cut slightly different material.
  • Switching the job between combined, vector only, and raster only.

Individual understands the concepts:

  • Engraving on anodized metals.
  • Creating hinged parts on the laser.
  • Knowing when it is safe and applicable to turn off air assist.
  • Engraving images.
  • Optimizing laser files to minimize wasted material and job time.
  • Selecting an appropriate laser bed.


Level 2

Individual has demonstrated they are capable of:

  • Realigning and resuming a moved part using visible red laser alignment.
  • Replacing and recalibrating the auto focus.
  • Cleaning and lubricating guide rails and pulleys.
  • Changing the XY focus location.
  • Making jigs to engrave irregularly shaped items.

Individual understands the concepts:

  • Laser Cutting Kerf.
  • Using chemical agents to engrave on metal.
  • Understanding and identifying the effects of an un-level bed.
  • Knowing whether to change material settings or rerun a job which is not cutting through.
  • Using additive layering to create 3D models


Level 3

Individual has demonstrated they are capable of:

  • Extinguishing a fire.
  • Leveling the laser bed.
  • Focusing the laser mirrors.
  • Creating new material settings.
  • Ability to edit and prepare an image for optimal engraving.

Individual understands the concepts:

  • Impact of laser frequency.
  • Bottom-Up versus Top-Down engraving benefits.
  • Differentiation of image dithering algorithms.
  • Using additive layering to creating models with moving parts.