To cut or laser - that is the question

[Khalid Nazim]

I have an order coming up to supply 300 pcs of 3mm acrylic cut in 5 different sized rectangles for a hobby shop. I have got a price from the acrylic manufacturer for the supply of 2' x 4' sheets as well as prices for the acrylic cut in the sizes that I have to supply. I feel that I can save on cutting the sheets myself from the 2' x 4' sheets. Would I be better off cutting the sheets in the laser or cutting them on a table saw? I don't have much work on the laser currently so I am leaning towards doing it on the laser. However one concern I have is that the 2' x 4 sheets have the blue protective films on both sides and I read on some posts that this film has PVC in it or that I should remove this film before cutting. However I need to supply the sheets with the film on as per the customer requirements. So should I cut the sheets on the laser or on a table saw.

Regards
Khalid

[Jim Reinhard]

I would peel off the blue put transfer paper on it and then cut it with the laser.

[Mike Null]

I believe you'll melt the edges using a table saw. I have Freud blade for plastics on my saw and cut 3mm stuff yesterday. It had a ragged edge from too much heat build up--ok for my purposes but not for finished product.

[Greg Facer]

The masking is polyethylene, it should be fine to laser. Worst case is it doesn't cut clean, but I believe it works fine.

For table saw you need a 80tooth triple chip carbide tip blade to do a good job (and a good saw too!) otherwise it's only a matter of how much chipping. Melting is from a dull blade, and acrylic / plastic blades should not cut wood ever! If wears the blade differently than plastic. If you don't have the blade, I'd try the laser as its about $60-$100 for the right blade.

Greg

[Dan Hintz]

Three questions to ask yourself (knowing the mask is laser-safe):
1) Is it faster to cut on the table saw (for simple shapes, the answer is often yes)?
2) How accurate do I need to be?
3) Do I need polished edges?

[Mike Null]

Greg

Welcome to SMC.

My blade is an 80 tooth plastic laminate blade and nearly new--melting is not from a dull blade. If you use a zero clearance insert you shouldn't have any chipping.

[Jim Reinhard]

I cut with the blue film on before , I stopped and swithed to the trasfer paper ,dont rebember why.But I am thinking the coating was melting and catching fire.I also think it was on 3/4 acrylic so cutting speed was very slow .

[Joe Pelonio]

I would peel off the blue put transfer paper on it and then cut it with the laser.

I would do this too, if they need a nice clean glossy edge, and accurate sizing. The table saw with appropriate blade can do a good job cutting but will not have smooth edges, and is harder to make them all exactly the same size.

[Khalid Nazim]

To move this along, my requirements are:

1) I am assuming that it would be faster to cut on the table saw than on the laser - i dont currently have a table saw :)
2) I dont need these sheets to be super accurate in size
3) I dont need polished edges

I would like to cut the sheets on the laser but am not sure if its safe to leave the film on. I dont want to peel the film off and put transfer paper on. Thats too much work for this order. I would rather have the manufacture cut it for me. So would it be safe for me to cut the acrylic with the film on in the laser?

One last thing, I saw a knife being sold at HD next to the plexi sheets stating that I can slide the knife on the sheet against a ruler and then break the sheet using the edge of a table. Any idea if this would work?

Thanks
Regards
Khalid

[Scott Challoner]

Your supplier would probably be willing to put on paper mask for you for a small charge. They will also cut it for you. Depending on the quantity, they may cut for free or for another small fee. Yes you can score it with a knife and break it. For that matter, you could probably score it with the laser at a much faster speed than cutting all the way through and deeper than just scratching with the knife. Of course this won't work with any shapes, just straight lines.

[Conrad Fiore]

I have cut to .005" on a table saw without problems. A good plastic supplier should be able to do the same and I would think that you will make a better mark-up having them saw and you re-sell. I would also suggest that you specify cast acrylic that is paper masked or at least a high tack poly masking. If there is to be any follow-up machining, that blue film is the worst. Because of it's low tack, it will lift too easily when additional machining is performed after cutting. The cheap extruded, blue film acrylic is also the reason why so many people have problems cutting without melting and chipping.

[Joe Hillmann]

What are the sizes of the squares you are going to need? Have you ever tried cutting plexiglass with your laser? If it were me I would cut it on a table saw with a zero clearance insert rather than on the laser. It would be much quicker that way (assuming the squares aren't tiny)

[Khalid Nazim]

I have cut plexi on my machine but those were ornamental figures. These are just rectangles. Sizes are 12" x 12", 12" x 18" and few other sizes. If I decide on cutting this on a saw, then I will have to go and buy one - which I dont mind :)

[Joe Hillmann]

I think a saw would be much much quicker. I also would suggest you get or make a zero clearance insert ( http://woodgears.ca/delta_saw/insert.html ), it will make a huge difference in cut quality and is safer if you end up with small off cuts.

Also you say you don't have a table saw yet, so I don't know if you have experience with them, you might wan't to do some reading or look on youtube about how to use it safely. There are many really dangerous things you can do on a table saw that aren't intuitively dangerous.

[Lee DeRaud]

I think a saw would be much much quicker. I also would suggest you get or make a zero clearance insert ( http://woodgears.ca/delta_saw/insert.html ), it will make a huge difference in cut quality and is safer if you end up with small off cuts.It's not even a contest, especially since you can stack and cut a whole pile of them at once...that's how I cut 24x48's down to "laser-sized" pieces. Just tape the stack together in a couple places on each edge and treat it as one thick (3/4"-1") slab. Also helps to run a strip of tape down each cut line.

[John Frazee]

I used to cut my own acrylic for putting over cerificates and pictures on plaques. I made a jig for beveling the edges on the tablesaw as well and it all came out just fine. I used the acrylic with the blue protective covering. I didn't have to buy any special blade.

[Michael Hunter]

Acrylic normally comes in big big sheets (around 6' x 10'), so the supplier is already cutting it down to 2x4 for you.
How much extra would he charge to cut it to exactly the right dimensions for your customer?
Probably not too much more so long as there are not too many different sizes.

[Kevin L. Waldron]

We use this blade for cutting cast acrylic from 1/8" to 1" and usually cut approximately 100 sheets a month and all sizes in between. We also use the same saw to cut probably 50 sheets of plywood and 20 sheets of melamine a month. Blade will last about 3 months without a sharping...... no burning/tearouts...... or bad cuts. We've probably used 15 of these blades.
221492

Kevin

[Michael Kowalczyk]

Hey Kevin,
Nice blade but as mentioned above you should use 2 different blades. One for plastics, one for plywood and one for solid woods. I can speak from experience that it does make a difference. Once you cut plastic/acrylic with a blade it will never cut wood the same as prior to being used in the plastics world. Changing blades per material will get you a longer lifespan between sharpenings. We just magic marker them as to what material they are used for.

[Rodne Gold]

Buy the table saw , it will come in handy , far quicker than using the laser anyway.

[Khalid Nazim]

Thanks everyone for your suggestions. I think I will go with buying a saw and cutting the acrylic myself from larger sheets. That way I can get a saw and get to practice cutting as well. Any ideas on what table saw should I buy? I don't want something which is too expensive or big.

What about buying a circular saw with the guiderails?

Regards
Khalid

[Conrad Fiore]

How about a Made in Canada table saw?
http://general.ca/site_general/g_produits/saw/350R_650R.html

[Lee DeRaud]

What about buying a circular saw with the guiderails?That kind of setup is great if (1) you're very limited on workshop space or (2) have a need for portability. Where they fall short (relative to a tablesaw) is exactly the situation you're in: high-production-rate repetitive cuts. And a good one (e.g. Festool) can easily cost as much as a tablesaw sufficient to your needs: you don't need a 5HP cabinet saw and 48" of rip capacity to cut acrylic, a sub-$500 contractor saw will do that quite nicely.

(The guided-saw proponents will be along shortly with torches and pitchforks to teach me the errors of my ways. So it goes.)