What's the best way to cut plexi?

[Sulla]

Making some LCARS panels and a few odds and ends from a big sheet of 1/8" thick plxi.

I have had no sucess with scoring and breaking. I was wondering about trying a band saw, or is there something else? I'd like to be able to make some good clean cuts with as little clean up as possible.

FYI: Some pieces will be small like 3/4" x 3" but other pieces will be as big as 1' x 3'.

Any ideas?

 

[micdavis]

NEW, SHARP table saw blade. They even make them for plex (acrylic). Plexiglass is a brand name.

Sandwiching the sheet between two boards helps too. In a pinch.

 

[Darth Detroit]

NEW, SHARP table saw blade. They even make them for plex (acrylic). Plexiglass is a brand name.

Sandwiching the sheet between two boards helps too. In a pinch.

What he said
Or use masking tape. Draw your line on the masking tape and go at a nice steady pace. Dont push or rush it.

 

[micdavis]

Yes, masking tape. Forgot about that. Can be tricky by coming off (rolling up) as you push it through the saw.

 

[TFrosst]

Band saw should give you a nice edge. As should a tablesaw. But as stated, go slow and tape it. You can flame the edges with a torch after they're cut and they'll be super smooth. just make sure you dont' burn the acrylic

In regards to the scoring, are you using the proper acrylic scoring knife?

 

[Sulla]

Thanks all! For the great info!

In regards to the scoring, are you using the proper acrylic scoring knife?

And nope, I sure wasn't. I had a scrap piece I was playing with. My nice large sheet is still unscathed, awaiting a more 'proper' cutting method.

 

[wannab]

Table saw -- One trick that reduces chipping is to set the table saw blade low just past the surface of the material being cut, what this does is position the teeth of the blade so they cut back towards the material instead of straight down which makes more bottom/back chipping happen. Hope that makes sense.

Band saw blades -- use a metal cutting blade instead of a wood blade, it'll give you a smoother edge. Also for tight cutting turns use a 1/8" blade instead of a 1/4" blade.

Doug

 

[exoray]

Table saw -- One trick that reduces chipping is to set the table saw blade low just past the surface of the material being cut, what this does is position the teeth of the blade so they cut back towards the material instead of straight down which makes more bottom/back chipping happen. Hope that makes sense.

You can also mount the blade backwards on a table saw, this will avoid any grabbing by the teeth...

It obviously won't cut as clean or fast but it will still cut, and it will in many cases heat up enough to actually get a more polished cut edge...

 

[asavage]

At the plastics shops, they use what's called a triple-chip 60 or 80 toothed saw blade. That means that one tooth slants in one direction, the one after it is straight across, and third slants in the opposite direction. It also has what's referred to as a "Zero Draft" which means that the sides of the carbon teeth don't stick out from the sides of the blade at all.

Cuts beautifully, but in any shop where you have one, DON'T LET ANYONE ever cut anything but plex with the blades.

Clearly label.

You can also mount the blade backwards on a table saw, this will avoid any grabbing by the teeth...

It obviously won't cut as clean or fast but it will still cut, and it will in many cases heat up enough to actually get a more polished cut edge...

 

[Vaderman]

Laser
:love

 

[SurferGeek]

At the plastics shops, they use what's called a triple-chip 60 or 80 toothed saw blade.

These blades aren't cheap but well worth the cost... about $70-$90 a pop. Prepping the plastic with tape, correct speed on the saw and moving at a slow, even pace will leave a edge that requires almost no further work, especially when using a new blade. Some of the blades say you can use them on plastic, MDF, chipboard and such but I wouldn't recommend anything but plastic. You'll get much longer life out of it.

Here's the one that I have used:

http://www.amazon.com/Freud-LU94M010-10-Inch-Plexiglass-Plastic/dp/B00004T7AL/

 

[runnriottt]

Great info in this thread. You all are awsome!

 

[Sulla]

Great info in this thread. You all are awsome!

I second that!

Exactly the stuff I needed to know about, thanks everyone.

 

[howlingwind13]

I was cutting a lot of plexi over the last 2 years for my haunted house,
I bought the special blades and stuff, but still got a little chippy.
One day I fired up the up the grinder and used that, it was super fast, accurate and no splits, or chips.
The only thing is wear a face mask or shield, glasses and long sleeves.
I had a hot piece of plexi stab into my bicep and then cool while I was still cutting. Burned like hell fire.
mike

 

[micdavis]

To be sure if you lay out the money for a good plex cutting blade, ONLY cut plastic with it.

I also used to leave a big stick of pattern makers wax on the table saw, run it into the blade now and again while cutting plastic, helps keep it sharper longer.

 

[Sulla]

So what's the best way to clean plexi?

here's my cutting diagram

 

[GuntahKela]

I use a jigsaw or my dremel cutting wheel. I do a lot of curvy plexy cutting, and the dremel disk gives me a lot of freedom. Always cut first, then remove the protective adhesive paper when done.

 

[Sulla]

Resurecting this... I need to finally cut some plexi this weekend on my own. I don't have the correct circular saw blade nor do I have a band saw.

I can use my dremmel, but the pieces are large - about 3' x 2'. Is tehre a special kind of acrylic scoring knife I could pick up at a hardware store like Home Depot or the like?

 

[kalarcana]

Resurecting this... I need to finally cut some plexi this weekend on my own. I don't have the correct circular saw blade nor do I have a band saw.

I can use my dremmel, but the pieces are large - about 3' x 2'. Is tehre a special kind of acrylic scoring knife I could pick up at a hardware store like Home Depot or the like?

Andy,


Both Home Depot and Lowes here have the acrylic knives. They ran about $5 and were located in the same area as the plexi. If you can't find one let me know and I'll send you one.



Rick

 

[Sulla]

Awesome. Thanks for the info and for the offer.

I'll hit the local stores and see what I can find.