View Full Version : is it safe to cut vinyl?

Nadia Zois
12-10-2008, 12:47 AM
i had a request to make things out of vinyl but i want to be sure it is safe to do so. i have read about some things creating toxic fumes when cut so i was worried.

Mike Null
12-10-2008, 6:02 AM

There have been several threads on the hazards of cutting materials containing pvc. If you'll do a search they will come up.

Joe Pelonio
12-10-2008, 9:10 AM
Vinyl is polyvinyl chloride, the key word being chloride, which creates the toxic/corrosive gas when burned. Vinyl products may contain varying amounts of it because there are many formulations mixed with other plastics, but in general I'd stay away from it.

Dave Johnson29
12-10-2008, 9:33 AM
i have read about some things creating toxic fumes when cut so i was worried.

Hi Nadia,

It creates fumes that mix with the moisture in the air to create small amounts of Hydrochloric Acid (HCL). Actually that should be HCl <- lower case "L" but it looks like HCi so I am using upper case "L"

If you have an effective forced-air fume extraction system, the HCL will be ducted outside. It is only tiny amounts of acid being formed but it will cause rust on the steel components in your machine if it is not extracted as it is being created.

Check this link for a simple extraction system that cost me under 200-bucks.


With the extractor system running, cutting or marking PVC should not present a problem. However that is a decision you and only you can make.

I have been a Mechanical Engineer for 40+ years and designed many industrial exhaust-air-cleaning systems (called air-scrubbers). I am comfortable cutting PVC with my laser -- providing -- the extraction system is on and operating at full power which is rated at 600+ cubic feet per minute.

Mike Null
12-10-2008, 9:40 AM
After you've read and seen the examples of where others have used their machines for cutting pvc type material and read your warranty you will consider seriously whether you should cut it.

Many of the manufacturers advise against doing it to the extent that it may void the warranties.

All that said, if its just a small amount I would cut it.

Rich Enders
12-10-2008, 10:03 AM
Poly Vinyl Chloride (PVC) is used in piping, siding, electrical insulation, medical solution bags (blood, and IV), baby bottle nipples, fabric coatings, and more. It is chosen because it can be formulated with reinforcing fillers or plasticizers to be either rigid, or flexible, it inherently resists burning, it is easy to glue, and it is one of the lowest cost resins available. It is safe for containing food, and drinking water. You can work with it with some precautions.

The toxic/corrosive aspect comes if PVC is heated above about 400-450 F. At his point it will free up chlorine which then combines with moisture in the air to form hydrochloric acid (HCl). Concentrated HCl will corrode some metals, and is not healthy for any living thing. On the other hand, it is used in swimming pools to control bacteria, and is the very acid we build in our body to digest food.

PVC will melt without releasing chlorine at about 300-360 F. If you can keep the concentration of HCl down, you can work with PVC above those temperatures, even to the point of causing it to burn. I am not sure how your laser is set up, but if the business end is open to the air, then you need good air flow around you to keep the concentration down, and all metal in the area needs to be stainless steel, or brass.

Joe Pelonio
12-10-2008, 10:19 AM
After you've read and seen the examples of where others have used their machines for cutting pvc type material and read your warranty you will consider seriously whether you should cut it.

I wish I had a picture, but I did see a machine that was used for one job cutting 3mm PVC (Sintra) lettering and it was totally destroyed by the corrosive fumes, never to be used again. Since then the owner has done only rotary engraving.

Scott Shepherd
12-10-2008, 11:16 AM
As Joe has mentioned several times, if you wish to do this, you need to find a Polyester Film, not a Vinyl. The brands are out there, just look for Polyester instead of Vinyl.

Richard Rumancik
12-10-2008, 1:12 PM
There is a substantial difference between cutting vinyl film and cutting PVC sheet. Compare the "volume" of PVC that gets decomposed when you cut .003" film vs. .125" sheet. (Probably 40-60 times as much for the sheet). If you mark vinyl film, the outgassing would be quite minimal. Many vinyls will turn a golden color when marked and this can be used to advantage. I would not cut PVC sheet, however, or cut vinyl fabrics, as the risk is not worth it to me.

If you choose to cut thin film, it would be a good idea to keep fumes directed away from mirrors; do not do this without air assist or you could ruin your lens. It would also be prudent to wash down any areas having smoke deposits after the job with soap and water (maybe add something to neutralize any acidic deposits eg bicarbonate). Try to keep the smoke off the cutting table (grid/honeycomb) or else you may need to pressure wash it. Clean lenses, mirrors and rails after the job and any metal parts in the area. Remove any scrap material from the room asap. Keep your face out of the enclosure and let it exhaust after the job. If you have any adverse reaction it would be best not to proceed.

Of course the laser companies will void the warranty if you do it; they have no control as to what precautions (if any) are taken and it will just mean more replacement parts for them. However the warranty limitation would probably apply to bearings, rails, etc. I understand some systems draw the contaminated air over the laser tube (not a good design in my opinion). If you laser does this, think twice. But if the exhaust air is independent like it should be, then I don't see how laser tubes, power supplies, and main board could be excluded from warranty. If you send in a corroded rail for warranty purposes they will know what you did.

Even with industrial systems cutting PVC sheet is not considered to be very desirable. Sometimes they use chemical scrubbers to neutralize the acidic gasses.