EPILOG LASER CUTTERS
layer color, object property color, line quality
vector/raster & layer line quality
All shop users will have taken an orientation session that goes over our laser cutter safety rules in depth. Access requires a signed
agreement which includes these 3 rules. All users MUST remember and follow these at all times. We offer an extraordinarily accessible
laser cutter resource to users in the school of architecture (under normal circumstances, 24/7 during any given semester). In return,
all users must rise to the occasion and operate these machines, which are always fire hazards even during correct use
, with an equivalent
level of responsible behavior.
All users will be required sign a user agreement for laser cutter and general shop access; access may be revoked
indefinitely for willful disregard of safety rules. Laser cutter safety rules are:
All users MUST WATCH the cut the entire time it runs. This means watching right at the machine,
standing or sitting on a tall stool,
and being able to immediately see any sign of a problem - without any delay. Laser cutters work by
cutting/melting - every job is a fire hazard.
Being in the room is not adequate machine supervision. Being near the machine does not qualify as following this
rule unless you are directly facing/watching with a clear view of the whole bed and the cut as it happens, until it finishes.
You must be able to react to any beginning sign of a problem IMMEDIATELY, without any delay.
Users can only cut approved material - refer to our lists (link to be added - printed lists posted @ each machine) for what is/isn't allowed.
Many things are not safe to burn
in an enviroment like this (comparable to a kitchen stove with a vent outside) - many materials burn with hideous results, as well. So you
must make sure anything you want to put in the machine is on OUR "ok" list first. Do not go by the list of any other shop.
You cannot lend your access to anyone. Users gain access to laser cutters as part of shop access, with a long safety orientation - that
access cannot be given to anyone else. Just as you cannot give your ID card
out to others, you cannot give them access to these machines - regardless of their experience. If the machine is operating, it must be done by
the one whose access information has been used (you will sign in to print with your MIT name/password).
Shop orientation includes a more detailed explanation of these safety rules. It may be added to this website in writing, when time allows.
All users can contact shop staff for training and re-training on these and any other subjects at any time. Willful failure to follow these
rules will result in loss of access to the shop, and required remedial retraining for the possibility of restoration of access.
MIT policies dictate that you do not attempt to put out a fire if you do not have the training or equipment necessary - we go over what to do
in case of a fire, in detail, during the orientation session. Your top priority as a laser cutter operator will be to prevent a fire from
happening to begin with.
Epilog Tutorial PDF on Wiki
Laser cutters can be reserved for up to 2 hours a day per user, on Reservations
Reservations are not required, but will take priority (2 hrs/day maximum).
There are a number of ways to send information to the laser cutter; this tutorial is intentionally
This tutorial is meant as a reference for trained users, and
provides a step by step process based on Rhino CAD software.
Geometry can be generated and sent to the laser cutter by a number of different softwares. This tutorial will demonstrate
how one can send jobs using Rhino.
Geometry for cutting can either be generated in Rhino or imported from other CAD softwares. Keep in mind that importing geometry
can bring issues that can be avoided by starting with a new, clean file. if that isn't possible, properties of imported geometry
must be checked in detail to ensure all settings are consistent and as expected before attempting to plot.
-Begin by opening Rhino and opening a file, importing, or starting a new one- make sure your units are consistent from drawing to plotting!
-Drawings should be formatted to fit into a 24x36 inch bounding box that represents
the physical dimensions of the laser bed. It is not possible to cut materials with larger dimensions than 24x36 in.
TL;DR? Quick reference (if new to this, please don't skip thorough instructions)
- check units, scale and orient drawing at 0,0, also check layer/object colors for consistency.
- draw reference rectangles for 24x36 bed and material piece size/location, if different.
- organize cut lines & reference lines by layer - change line quality (print width, by layer) to "hairline" for vector line cutting,
"no print" for reference lines. ONLY if you have pixels to raster, (make a separate layer) and leave its line quality at 'default'.
- set focal distance MANUALLY with 6" combo square (as in photos) - remember that you ideally want the 2" focal distance in the CENTER
of your material (we use 2" lenses in all our machines). Also remember that if your material is not flat, the focal distance will not shift
to meet it - the lens case only moves in
X and Y during a job. Bad focus can ruin cut quality and is much more likely to start real fires, so always, always use the flattest
material possible, and cut up large pieces if they cannot be flexed to flatten (chipboard can be coaxed into shape, somewhat - acrylic
cannot). If your focal distance is bad, the cut will be messy - and more likely to burn out of control.
- Check and change the power/speed/ppi settings to match your material - test first - never assume that settings will be perfect, even if they've
worked in an identical situation previously. Many factors combine to affect cut results, and can change from job to job even with identical settings,
machine, and material.
These settings are very important!
- Posters with settings to test are at each machine, on the wall. Never neglect these 3 settings, or your focal distance - small problems with
them can make a big difference in the results, and be the difference between a safe cut and a blazing fire. We do not give you sets of numbers
to blindly trust as material settings - it is important for you to test and inspect results. Same material, same settings will NOT
necessarily product the same results every time. It's better for you to understand and have control over these numbers. If you have more than
one type of cut (cut/etch, cut/raster, etc) then you need to use "color mapping" to set specific power/speed/ppi settings for
multiple layers. Correct settings are absolutely necessary - never use the defaults!
- Start the job, and watch it UNTIL IT FINISHES. If you must walk away, you must pause it first. Be ready to react to any excessive smoke
or flame - these may come from the material itself, or from below it inside the machine. It can happen at any point, and a good-looking cut
can go very bad without warning. Never let your guard down while a machine operates, for any reason.
To reduce risk of charring or fire, there are several things you must always check.
To start, make sure your drawing is clean. Get rid of any duplicate objects, make sure control points are
on any objects in the cut window.
These things will cause repeated cutting over one spot, which burns badly.
Layers must also be completely cleaned up - no redundancies or inconsistencies. Check all your object properties
as well as all the identifying colors. Set only one layer for each identifying color (easiest to do if you
copy/paste just what you need into a clean new 3dm file).
If your drawing is big and cluttered (this happens frequently),
then please copy and paste just the curves you need into a new file, and clean it there. As an example - we often see 3dm
files with multiple layers with overlapping color properties. This can cause major issues with print settings that
are obnoxious to troubleshoot,
and even worse, be a pretty serious fire hazard. Please do not try to cut from a 3dm like this as-is - move cut parts
into a clean new file.
In addition, curves drawn too close together can also start a fire. We've seen drawings with tightly packed
notches, in attempts at flexures in corrugated cardboard, that showed signs of starting to burn out of control.
If you are cutting acrylic, you MUST remove the upper layer of scratch protective film. The settings that are perfect for thick acrylic are
Very Bad for a thin piece of paper on top.
Perfect-as-possible focus is crucial.
You need to set focus manually to really have control over it (autofocus is glitchy at best, and doesn't adjust to
the center of material of any thickness), and you've got to keep in mind that warped material has varying Z height, and will often not be at the actual
Use the 6" combo squares (anything that can accurately show you 2 inches from the material will work; these tools just make it visually obvious)
to set the bottom edge of the lens case 2 inches away from the CENTER of your material.
Use the manual up/down button to adjust - this button is at the front left side of the machine, just INSIDE of the large lid. It
is not on the exterior of the machine.
We do not require users to clean lenses for each job. However, if you are cutting thicker, denser material, you will produce
more smoke, and dirty the lens faster - in this case, it should be cleaned. It's also a good idea to check to see if the
user before you left a mess behind. Under normal shop operation, we have student monitors cleaning the lenses once every day.
This works fairly well, except when a lot of nasty material like Masonite is processed, which produces lots of greasy soot.
More detail on how to clean lenses will be added here soon - in the meantime, please ask for a quick in-person tutorial on how
to correctly clean the Epilog lenses.
Layers and Their Settings Are Important
In the example below, the laser would first etch the red lines, then proceed to cut the green
circle, and finally cut the outer rectangle. Line color/using layers identified by color is how we instruct the laser cutter about operation order.
The sequencing on laesr cutters should be ordered: etching -----> interior cuts -----> exterior cuts.
In any CNC type file setup, it is important to order cutting operations from inside to outside, if this applies to your drawing - the reason being
that if exterior cuts are done first, if parts are cut loose, there's nothing to stop them from shifting before the interior operations are completed-
resulting at best in ruined parts.
Thinking ahead and setting up sensible cut order is important on all kinds of work - even more crucial to set correctly in CNC jobs for the
water jet or any of the 3-axis routers.
In order to sequence the cutting of your drawing, if you have interior and exterior details, and/or a mix of etched/cut/rastered details,
you may need to separate the geometry into individual layers, to properly control cut properties (power/speed/ppi) as well as cut order.
This is done in the "color mapping" tab, explained below.
One set of power/Speed/PPI settings can be changed on the main "properties" page if you only have one cut type.
If you have more than one, and need different settings for each, you can do this by using "color mapping".
Regarding Layer/Object Colors and Corresponding Color Mapping Settings
If you are using the Color Mapping tab, you MUST make sure your layer colors and color mapping colors match exactly.
Any curves in the print window that have inconsistencies in layer/object color and the settings here will result in
those objects being cut at 'default' settings - which can be very dangerous, causing material to immediately burst into
flames, depending on how incompatible those settings are with whatever material you happen to be using at the moment.
When you adjust settings for each layer in color mapping, you MUST click the "modify" button, or else the changes won't be saved!
If you are starting with a crowded Rhino file, especially with multiple layers of the same color, please export the curves you need into a clean, new file, separated by layer color,
and without any redundancies.
We've seen many instances of 3dm files with multiple 'black' layers that sometimes have differing properties otherwise, resulting
in unexpected machine behavior (not matching your print settings) - which can easily ruin your material, and also start a fire on top of that.
In any case, but especially if you are working with imported curves, especially, also check object properties (select them) to make sure your
object colors and layer colors match. If they do not, you may get bad results (destructive & sometimes dangerous on laser cutters!).
But, if all your cut lines are the same quality (same layer, same color), you don't need color mapping. The printer driver should
automatically reorder cuts to move from interior to exterior.
Again, these power/speed/ppi Vector settings (when you only have one cut type)
are on the Properties window:
The vector/raster settings are also important. Inconsistent settings for a fully vector (curve only) cut can cause the machine to
skip right over a job and say "done!" without actually doing anything. You only want rastering settings on if you're burning pixels.
Below is an example of layer separation and vector line width settings, which must
be edited before trying to cut.
Do NOT leave layers at "default" print width for curve drawings - always "hairline" (aka 0 line width)
Before attemtping to plot, SELECT ALL and change the line weight of all objects in cut layers to HAIRLINE, by using the drop down menu shown
Do not leave lines set to default. It may or may not work if you do.
**Also, be sure to place any reference or irrelevant parts to a 'NO PRINT' layer within the Layer
Manager (or adjust print visibility properties to exclude certain types of objects)! Otherwise, the laser will try and cut out the
reference rectangles, potentially damaging your project and the machine. "No print" is at the very bottom of the print width selection list.
Power/speed section TBA: please reference printed posters at each machine. Note that they are different for each machine -
each Epilog has a different power output, so the settings are NOT the same
Not Allowed Materials List
- mat board
- chip board
- other thick paper (thin paper is possible but can burn out of control easily)
- corrugated cardboard: remember that cardboard is a few sheets of very thin paper in a funky configuration,
with a lot of air in between. This makes it very flammable. It is allowed to be cut in our machines, but users MUST always
be extremely careful with settings and focus to make sure it's done safely.
- thin sheets of balsa
- thin basswood
- thin plywood
- Acrylic is a stiff, clear plastic that is allowed in laser cutters. Plexiglas is a well-known brand name of acrylic.
Thin Masonite (another brand name) is allowed- it is, however, messy to cut, so users must be careful with it, and get training to
clean lenses after cutting. Masonite makes an exceptional amount of greasy smoke when cut.
- Avoid thicker materials, especially wood/plywood/MDF/Masonite. Users must remember that these machines are limited in power output, and that they cannot safely handle thicker materials -
thin plywood is ok. Thin sheets of solid wood are ok. Very thin MDF is ok, if just barely. but thicker sheets of these kinds of
materials will burn badly and should NOT be cut on the laser cutters - we have other machines for that kind of work. Please check
with us before even attempting to cut any thick sheet material in these machines.
- Thin nylon or polyester/Mylar can be cut; thicker sheets may not cut well.
- Cellulose acetate is a clear flexible type of sheet material - it is extremely flammable, though, so power settings MUST be turned
down to their absolute minimum.
- Natural rubber can be cut (think rubber stamps). Silicone is NOT a natural rubber.
- Some sheet materials are mixtures/composites - we need product-specific SDS sheets to determine whether any composite or laminated
material is safe or not.
- Natural fabrics may be possible - but flammability may be a serious issue so check with us first.
If you want to cut anything that is not listed here, you must email Archshops with product-specific information
(we need the SDS sheet) - please locate this before you buy the material, in case it is not safe to laser cut.
- never: PVC (of any type, foamed, solid, or vinyl cutter vinyl)
- never: polycarbonate (Lexan etc)
- never: ABS/polystyrene
- never: foam core, gator board or any other foam sheet
- never: Neoprene
- never: thick PETG (thin PETG is possible but quality is bad)
- never: polyethylene/HDPE/LDPE (too gummy/flammable)
- never: polyurethane
- never: Delrin
- never: carbon fiber or fiberglass
- never: any reflective material
- never: teflon
- never: silicones
- never: other materials containing styrenes or chlorines
Because these machines cut by burning/melting, many materials are not able to safely/effectively
be cut in them - remember that the shops have
other machines that can cut many materials that are incompatible with the laser cutters. Please plan
ahead with us for any special needs, so you can get the results you want with the materials you need
- do not wait until time runs out and attempt an incompatible machine/material combination out of
desperation, which is dangerous and destructive.
Most wood and paper products are okay - but remember that anything mixed into/painted onto/glued onto them would also be
burned, and must also be taken into account. You must email us if it a material is in question for any reason.
As an example, cork sheet can be plain or mixed with a more durable rubber, like Neoprene. Plain cork is safe to cut;
synthetic rubber-impregnated cork sheet is not.
Acrylic is a safe clear plastic (many clear plastics are not)- you must remove the upper protective covering at minimum,
because the settings that work well for acrylic cutting are NOT good for that covering, and it will burn badly.
Also remember that with thicker material, as acrylic often is, you need to shift the focal point to the center
of the material - not the top - for decent cut results.
Thick/super dense material may also just require more power than these machines can provide, and not be safe to cut.
The hourglass-shaped beam makes the charring hazard higher with thick material. Thicker plywood, as an example of a
very common model making material that is of a type that is "safe" to laser cut, because of its thickness, burns excessively -
it must be cut on one of our routers instead.
Material that is too thin may also be too flammable to be safe to cut. In the case of very thick/dense materials or
super-thin ones, email us and ask first. Please do not risk fires by attempting to force an incompatible material thickness
in one of the Epilogs.
Thinner masonite and very thin MDF can be cut, but release messy soot/smoke and will char a lot, which is an excessive
fire hazard - please do not
attempt to cut masonite
or MDF thicker than 1/8". These should be cut on a router instead.
Foam core or other foamed boards are never allowed,
not even for etching- it's nearly impossible to get the surface of a
foam board to lay perfectly flat within the 2D focal plane - and the beam doesn't simply dissipate at the focal length,
regardless. For all these and other reasons, foamed materials start fires- so they are never allowed.
Many plastics are not allowed - some release poisonous/destructive byproducts when burned, some are just very damaging
to the machine, Some are just discolored/damaged by the heat, some are too flammable, and many are a combination of all these things.
We have other machines that can cut these materials. If you have a very specific material need, just ask so we can determine the appropriate way to work with it.
PVC and polycarbonate are 2 common plastics that are never allowed.
Silicone is never allowed.
Polyethylenes (HDPE, LDPE...) are not allowed. PETG may work if it's very thin - the heat damages it, though, so it should
not be laser cut. You must email archshops any time you have a specific material you want to cut where it isn't already
either approved or outlawed. Don't pull an unidentified sheet of plastic out of a bin and attempt to cut it without having
us check it first - we can often identify several different types of plastic with a close look.
If you see the machine bouncing around from curve to curve in a very inefficient way, try exploding
and rejoining all the curves in the job.
Turn the machine's 'pointer' on (button on lid panel) to check that the beam is traveling properly
through the machine to reach the material.
This visible red light is NOT a cutting beam - it's just a tool for quickly checking alignment of
all the mirrors that bring the beam to the bed.
To keep things manageable, set your job up in a clean file, and get rid of any redundant layer colors,
make sure object and layer properties all have
matching colors, choose 'hairline' for all vector cut layers, 'no print' for all reference objects,
check your unit properties, check all print settings -
piece size, scale, vector only settings (unless you have pixels and need rastering settings)
print window location, visibility (what is allowed to show up in the print window), and so on.
If you press "go" and the machine immediately beeps and says "done", this is an inconsistency in your
object/layer colors and/or the vector/raster
settings in the print setup. Checking/fixing them takes a little getting used to - pick through them in
detail to find the inconsistency. This is
a very common problem for users on our machines, and can
be prevented by keeping drawings for laser cutting strictly organized, or setting up clean new 3dm files
for printing with all extraneous detail removed completely.
Don't forget all the settings in the tabs on the left in the setup window (visibility, scale, etc. - see below) - several
of these tabs contain settings that can get tweaked
accidentally, and cause problems with your preview.
When you click "print", you'll be prompted by Papercut software for your MIT email (don't add @mit.edu)/password. You can "log in" for up to 30
minutes at a time, maximum. If the software doesn't pop up, make sure it's open.
The main power switch for the system is in the back of the room - the plain light switch (now painted yellow). Ignore the gray boxes to its left!
The green/red buttons on the lid panel are the start/pause buttons. If you need to interrupt the job for any reason, and hit 'stop', you can resume
the job where it paused by pushing 'go' again. Do this if you need to take your eyes off the cut for any reason, even for a very short period of time.
The lens assembly has a few parts you should understand - the curved tube is very important. It blows low psi air under the lens to keep smoke out of
the path of the beam. If this tube gets knocked out of place, or falls out, the lens may quickly get coated in soot and burn - so always check for its
presence, and proper location (it points to the spot where the cut happens (and where the red pointer beam should appear when you turn it on).
The plunger on the right is the autofocus sensor - but again, it's glitchy at best, so please avoid it if you can - it needs to be spotlessly clean
to function at all, however, if it must be used.
The mirror and its set screw are very important - but do NOT touch them-
only a few specially trained staff members should ever be working with them. They're very easy to misalign.
So while you should be aware of them as part of the whole system, ~do not~ attempt to adjust any of their parts.
The two screws indicated in the image are the ones that must be loosened to remove the lens case for cleaning. More on that soon.