Vector settings for 30watt Explorer II

[Tom Cullen]

Anyone care to offer the best Vector settings to cut 1/2 inch cast acrylic using an Explorer II ,30 watt laser?

[Joe Pelonio]

Tom,

I have 45 watts and cannot cut acrylic that thick. I cut 3/8" at 100% power speed 3.

If you want to try it set it for 1/4", cut once, then manually focus to
half way through and cut again. The edge will not be as nice as normal though.

[James & Zelma Litzmann]

I just tried to cut through 1/4 inch using 1.0 speed and 100 power, with a 50 watt and it did NOT work. Went over it twice and it still did NOT work.

J&Z

[Joe Pelonio]

I just tried to cut through 1/4 inch using 1.0 speed and 100 power, with a 50 watt and it did NOT work. Went over it twice and it still did NOT work.

J&Z
Somthing's funny about that. Does your owner's manual show settings for 1/4"? Also, did they advertise that it would cut 1/4" when you bought it?
In both cases my 45 watt Epilog says 3/8" maximum. 50w should be able to cut a little more, maybe 1/2".

Are you sure the speed was 1 and not 100? In other words, barely moving?

[James & Zelma Litzmann]

Yes, it is funny, but not exactly ha ha funny, these are some issues we are addressing (hopefully) and yes it was 1 speed 100 power, barely moving, 50 watt laser. I had the same results with 1/4" plywood today, not a good day so far. Anyhow, sorry I couldn't help with the setting.

J&Z

[Tom Cullen]

Believe it or not, I was actually able to cut thru a piece of 1/2 inch acrylic in one go..... okay the 30 watt laser was set at 100 power and just around the 1% speed mark with PPI 900 and was deathly slow. So slow in fact that it did a number on the edges of the cut. But I thought at least it could do it and maybe if I played around with the settings I could refine it?

[Kevin Huffman]

Being able to do this is going to be controlled by your lens.
If you have a smaller lens like a 1.5 inch lens, it is only going to be in focus for 1/8th inch.
If you have something like a 2.5 inch lens it is going to be in focus for 1/2 inch.
If you are using the stock 2.0 inch lens, you focus length is going to be 1/4 inch. Which would probably explain the issues with the edges getting ate up. The top and bottom probably have a lot of blowout, or really wide engraving because the beam is out of focus. It still can cut but it isn't going to be as nice as the center. Getting a larger lens will allow you stay in focus longer and have a cleaner cut.

You can also use the Enhanced Vector Function in the driver to give you more controlability over speed. It slows it down a lot more, which will make each % a smaller amount. A smaller amount for each % allows you to fine to the speed and get a better cut.

You can also adjust the PPI to a higher setting to give you a little better cut. I normally cut acylic at 1300-1400 PPI. Just to give me a nice smooth edge.

[Joe Pelonio]

Believe it or not, I was actually able to cut thru a piece of 1/2 inch acrylic in one go..... okay the 30 watt laser was set at 100 power and just around the 1% speed mark with PPI 900 and was deathly slow. So slow in fact that it did a number on the edges of the cut. But I thought at least it could do it and maybe if I played around with the settings I could refine it?
How about that! On mine we use "frequency" rather than PPI but it's really the same thing. For acrylic mine's set at 5000. I bet you'll have a better cut if you increase that. Going that slow keep an eye on it, you may get more of the protective paper flaming up.

[Tom Cullen]

Thanks Kevin,
I will be sure to try your advice, and yes you are correct, it is the 2" lens I'm using ( stock ). Joe, protective paper YIKES! I had no covering on it at all BUT! it was only a scrap piece that I used it to practice on. Although that is something worth keeping in mind. Do you guys know of an inexpensive way to make up a vector cutting surface? I know there are very good ones on the market( and expensive) but since I currently don"t do a lot off cutting I was looking for something I could through together, or find a reasonable substitute in a do it yourself store.

[Dave Jones]

There are cheap cutting grids available. Take a look at the first post of this thread:

http://www.sawmillcreek.org/showpost.php?p=401560&postcount=1

As you can see, the grids start at $50.

[Joe Pelonio]

Thanks Kevin,
I will be sure to try your advice, and yes you are correct, it is the 2" lens I'm using ( stock ). Joe, protective paper YIKES! I had no covering on it at all BUT! it was only a scrap piece that I used it to practice on. Although that is something worth keeping in mind. Do you guys know of an inexpensive way to make up a vector cutting surface? I know there are very good ones on the market( and expensive) but since I currently don"t do a lot off cutting I was looking for something I could through together, or find a reasonable substitute in a do it yourself store.
Tom,

You don't have to have the protective paper on, clear and transparent
colors cut fine without it, but black and white tend to get discolored if you remove the paper. If using extruded that has the bluish plastic film you can leave that on too but it's hard to get the edge started when you remove it as it sort of welds itself on. I do more cutting than engraving
and wore out my vector grid after a year, but the new honeycomb was only $30 from Epilog.

[Rodne Gold]

A 30 w explorer will cut at best 8mm pex , 10mm is marginal. no matter what lens you use, you will not get thru 12.5mm pex even with a 4" lens as there is not enough power density in the spot size
Pex acts as a waveguide type material so the beam does not diverge as radically from the focal point and you can actually cut thicker stuff than other materials.
If you cant cut 1/4" with a 50 w explorer you have a major alignment or tube problem (probably the latter if it has a deos tube)
Multipass cutting of pex is a disaster as the key to cutting pex is how the melt is handled and partial cutting does not eject the melt thru the back of the cut and it resolidifies in the cut. You might do it , but edge quality will be shocking.
Air assist is the vital element of pex cutting and edge quality , not ppi tho ppi is important. Ideally you need a single cut with the melt being ejected thru the back of the cut , air pressure should be strong enough and directed enough to do this , but not too strong as to cause cooling and thus non polished edges , it should be strong enough to stop flaming.
Protective paper is recommended for subsequent handling and to stop the melt running over the surface of the pex and resolidifing on it (very difficult to remove)

[Joe Pelonio]

Protective paper is recommended for subsequent handling and to stop the melt running over the surface of the pex and resolidifing on it (very difficult to remove)
You mention an important point, subsequent handling. When shipping a large quantity of acrylic items it's good to leave the paper on. I learned this the hard way. These items are also engraved one side, so I remove the paper, engrave, apply transfer tape then cut. Leave the paper and transfer tape on and ship.

What happened one time is that when I peeled the paper and packed them up, some of the sawdust from saw cutting the 4x8 sheets to 12x24
that was still on the protective paper was attracted to the finished pieces by static. During shipping there was movement between the pieces and they arrived badly scratched up by the sawdust.