What materials should you never engrave/cut?

[Brian Rodenz]

My new epilog Mini 24 40 watt is scheduled for delivery on Friday. I've read that I should never engrave PVC unless I want to damage my machine and breath in toxic fumes, but aside from that, what other materials should I avoid working with because it simply wont engrave or it would be toxic.

[Dan Hintz]

There are a slew of materials that you either shouldn't or can't cut (particularly with a 40W)...

Fiber laminates are one such beast (carbon fiber, FR-4, fiberglass, etc.), any "-chlorides", etc.

[David Somers]

Brian,

To add to what Dan said, one way to get a feel for a particular product is to look up its MSDS or Material Safety Data Sheet. It will go into the material in depth from a variety of viewpoints, including the effects of fire and heat on it. That can give you a very good idea as to the safety of a product for lasing or any other use for that matter.

If you do a Google search for the product name, or the material name, and MSDS you will usually get a bunch of hits back. Pick the most current one since you will often find older copies out there and they may have been updated.

Dave

[chris szlachetka]

Good question. If you setup a dust exhaust style blower replacing the micro bag with an aluminum exhaust tube & vent, the fumes should be sucked out... right ?

[Dave Sheldrake]

Good question. If you setup a dust exhaust style blower replacing the micro bag with an aluminum exhaust tube & vent, the fumes should be sucked out... right ?

True but it just means you end up killing your neighbours rather than dying yourself.

cheers

Dave

[Gary Hair]

To add to what Dan said, one way to get a feel for a particular product is to look up its MSDS or Material Safety Data Sheet. It will go into the material in depth from a variety of viewpoints, including the effects of fire and heat on it. That can give you a very good idea as to the safety of a product for lasing or any other use for that matter.

Hogwash! Everything you laser is going to emit fumes that are probably not good for you and the MSDS will really not give you any idea about it's potential harm. Look up the MSDS for dihydrogen monoxide - if that doesn't scare the bejesus out of you nothing will... but, it does prove my point that you can easily misinterpret something if you don't know what you are looking at.

To answer the OP's question directly - there are really only two things that you should never laser - teflon and PVC - both emit toxic (and caustic for pvc) fumes that can do irreparable harm to people and equipment. There are other things that may not be good for you but nothing quite as bad as those two, especially in the concentrations you will be exposed to when lasering WITH a good exhaust system.

[Kev Williams]

Black Onyx.

I've shown pics of my ULS lens before, here it is again. Most of the missing pock-marked coating and scratches were caused by engraving a piece of black onyx for about 10 seconds. It was like engraving a mine field, small pieces literally exploded everywhere as the laser hit it. Looked like a miniature fireworks finale. Don't know if it was just THAT piece of black onyx, but I'm not going to bother finding out!


ulslens.jpg

[Dave Sheldrake]

Gary,

The MSDS will tell you if the fumes are particulate, noxious or toxic and that's a pretty good place to start.The section listing the by products of combustion is the main section to look at (usually found in the fire suppression / action section) There are a number of materials that give off far worse fumes / gasses than PVC and Teflon and there is a big difference between a vapour and a gas (Gas remains gas after cooling to ambient temperatures, vapours condense) Simple materials like synthetic carpeting contains acylonitrile that when decomposed by heat produces HCN gas and yet may only contain Nitrogen, Carbon and Hydrogen. HCN gas is NOT processed by many of the basic BOFA type filters and will pass through back into the air. Add in things like COCL2 that is produced by a larger number of materials than most people think and it can all get out of hand very quickly.

For industrial use having the materials MSDS on file for a processed material (one subject to decomposition by heat) is a legal requirement here in the UK and usually with good reason. Exhaust systems may protect users to some extent but having HCN belching out of your exhaust pipe is going to cause all sorts of problems even if the actual user isn't affected.

cheers

Dave

[Gary Hair]

The MSDS will tell you if the fumes are particulate, noxious or toxic and that's a pretty good place to start.

Would you laser the material associated with this msds?

FIRE AND EXPLOSIVE PROPERTIES:
Auto-Ignition Temperature 393 C/739 F
Flash Point- NA Flash Point Method
Flammable Limits- Upper NA
Lower NA
EXTINGUISHING MEDIA:
Use water spray, carbon dioxide, foam or dry chemical.
FIRE FIGHTING INSTRUCTIONS:
Fire fighters and others who may be exposed to products of combustion should wear full fire
fighting turn out gear (full Bunker Gear) and self-contained breathing apparatus (pressure
demand NIOSH approved or equivalent). Fire fighting equipment should be thoroughly
decontaminated after use.
FIRE AND EXPLOSION HAZARDS:
Heated material can form flammable vapors with air. Can include carbon monoxide, carbon
dioxide, small quantities of nitric oxides (NOx
), trace levels of hydrogen chloride and acetic acid.

SARA TITLE III, SECTION 313
This product does contain chemical(s), which are defined as toxic chemicals under and subject to
the reporting requirements of, Section 313 of Title III of the Superfund Amendments and
Reauthorization Act of 986 and 40 CFR Part 372. See Section 2
Ethyl acrylate
Methyl methacrylate
Aluminium
Copper
CALIFORNIA PROP 65 – CARCINOGEN
This product does contain the following chemical(s), as indicated below, currently on the
California list of Known Carcinogens.
Ethyl acrylate
Toluene
Mercury
This product may contain trace levels of components known to the state of California to cause
cancer:
Antimony (3+) Trioxide
Arsenic
Cadmium
Chromium (6+)
3.3'-Dichlorobenzidine
Formaldehyde
Lead
Nickel
Selenium Sulphide
MASSACHUSETTS RIGHT TO KNOW
This product does contain the following chemicals(s), as indicated below, currently on the
Massachusetts Right to Know Substance List.
Ethyl acrylate
Methyl methacrylate
Antimony (3+) Trioxide
Arsenic
Cadmium
Chromium (3+), (6+)
3.3'-Dichlorobenzidine
Formaldehyde
Lead
Nickel
Vinyl Acetate

[Dave Sheldrake]

Yes, it's basic aqcrylic, theres nothing on that MSDS that would give cause for great concerns.

EXTINGUISHING MEDIA:
Use water spray, carbon dioxide, foam or dry chemical.

That tells you it's not reactive to any great extent.

FIRE AND EXPLOSION HAZARDS:
Heated material can form flammable vapors with air. Can include carbon monoxide, carbon
dioxide, small quantities of nitric oxides (NOx
), trace levels of hydrogen chloride and acetic acid.

Some of them unpleasant but not particularly toxic.

SARA TITLE III, SECTION 313

Political Correctness gone mad. Coffee is also a class III carcinogen!

So yes, just reading the MSDS I wouldn't have too many concerns and that's without bothering to look up silly game posts about Cast or Extruded Acrylic. Pretty much anybody who does this kind of work at industrial or manufacturing level treats the MSDS as first contact before work.

cheers

Dave

[Bert Kemp]

Brian,

To add to what Dan said, one way to get a feel for a particular product is to look up its MSDS or Material Safety Data Sheet. It will go into the material in depth from a variety of viewpoints, including the effects of fire and heat on it. That can give you a very good idea as to the safety of a product for lasing or any other use for that matter.

If you do a Google search for the product name, or the material name, and MSDS you will usually get a bunch of hits back. Pick the most current one since you will often find older copies out there and they may have been updated.

Dave

Dave said "Pigs will fly wear a So'wester' hat in that event"
I'm prepared Davehat.jpg

[Kevin Gregerson]

Whomever said no to Teflon really has no idea. It's one of the greatest things to laser. Requires more than 40 watts though. Goretex really works best with 150 watts.

Most of your limitations are really more power limitations of 40 watts and PVC materials which will cut easily, just require really good salt water trap exhaust for safety reasons. PVC will also corrode your machine. Some machines handle this better than others.

[Gary Hair]

Whomever said no to Teflon really has no idea.

You might want to be careful spouting incorrect, and potentially fatal, information Kevin. Do some research and you'll find that Teflon has been know to be very harmful for a long time. Maybe you haven't been involved in lasers that long so you haven't hear about it yet...

http://en.wikipedia.org/wiki/Polymer_fume_fever

http://www.medicalnewstoday.com/releases/4716.php

[Kevin Gregerson]

You might want to be careful spouting incorrect, and potentially fatal, information Kevin. Do some research and you'll find that Teflon has been know to be very harmful for a long time. Maybe you haven't been involved in lasers that long so you haven't hear about it yet...

http://en.wikipedia.org/wiki/Polymer_fume_fever

http://www.medicalnewstoday.com/releases/4716.php

PTFE it self in in a fume form is bad. But in the form of being laser cut, it's really fairly easy to do and it does it well with no adverse effects to the machine. Many companies take the teflon coated wires and use a laser to strip the coating away. Millions and millions of dollars in Teflon products are worked with a Laser.