Laser Cutters

[ken]

I was thinking about getting a laser cutter, but I already have a CNC router and don't have the workshop area for both. If the laser cutter could go through a guitar body blank without burning it up, I'd be all over it.

ken

[David King]

Ken,
You just need enough wattage and that might happen.
I've found that the better the smoke extraction the less burning there is. That said the focal length is limited to a mm or two so you still need to take a lot of passes to get through 2" of wood. much cheaper to send out the laser work to someone who has one already. They could cut you a year's worth of forbon in a few hours for a lot less than the entry price.

[Jeff Callahan]

i have a 30 watt and a 60 watt. The 30 watt was my first machine and it cuts fine and will certainly get you buy for a long time. The 60 watt cuts forbon about 4 or 5 times faster than the 30 watt. The 30 watt has trouble cutting 1/2 inch acrylic- it starts to deflect too much but for up to 3/8 thick acrylic or forbon or pick guard material you shouldnt have any problem with a 30 watt- you shouldnt get any major deflection if you focus it correctly and keep the lenses clean. Its just going to be slow compared to a higher powered one like 80 strat bobbin bottoms in 50 minutes- something like that. Its been a while since I used the small one for cutting parts like that so that time may be + or =, it only really gets used anymore for one off unique items or for prototyping or making tooling.
As far as Corel all you really do with that if you have a good compatible cad program is you group objects together and weld the nodes. That way the lazer cuts in - well if you didnt it would cut each bit like all the corners first then the sides which makes for a crappy cut surface. Corel doesnt make a good program for doing mechanical drawings- you can make them but its a real workaround. The other thing corel does is you can scan things like pick guards and turn them into drawings- thats a useable feature.

Epilog just got back to me, they said it is doable to use a CAD program like you say, whether or not to use corel in between is a different point, but either way it is doable without having to "trace" over the original drawing. With Mojo's pricing and limited stock these days, the idea is getting more real. You don't need that old crappy "prototyping" laser anymore do you Jason?

[jason lollar]

I just had my laser sales guy out last friday, I decided to put a 50 watt tube in my old laser rather than buying a new one, it will basically double the speed almost. Anyway we talked about programming- yes you can print off autocad but he said you have to jump through alot of hoops everytime you want to print a job. I use a bone head drafting program 2 d - takes minimal learning time to use it and it does everything autocad will do for what we use it for and its only 40 bucks-you dont actually redraw stuff with the newest version of delta cad- all you do is weld nodes together but you really dont even need to do that if you dont care how long it takes to cut out parts- the laser can cut drawings that are a collection of lines but its cleaner and more efficient if you weld your perimiters so it cuts in a continuos motion. I think you can do all that in auto cad but- if you already know how to use auto cad maybe thats the way to go but if you dont how many hundred hours do you want to spend learning it? i looked at it recently because it would be good to update my huge backlog of drawings but autocad is too much- it does too much, training people with no experience would be an ordeal. Be careful about what the sales people at the lazer place tell you- they dont always explain with as much info as you should have to make a good decision
corel draw is an expensive program but nothing like auto cad
My local sales rep sold me a used machine the first time- it was completely refurbished and looked like new- you might check about that and save some $

[David King]

All the low power laser cutters I've seen simply move the head back and forth on the z axis while taking incremental steps on the y axis and turning on and off as needed. They don't follow 2-d shapes. Are there types that do move around in 2-D while cutting continuously? That would speed things like flatwork cut ups quite a bit.

It's essentially the difference between an inkjet printer and a plotter.

[David Schwab]

Thanks David,

My local guy works with my .iges files, but I think he has to "trace" over them before Corel sees them as vectors? Not really sure, but we've tried .dxf, .iges, .stl and a few others, but he can't simply pull the geometry and print without having to trace over them. Seems a little backwards to me. I'd like to get a machine and start experimenting. I bet there is a way to go from a file that Rhino can export to laser without any monkeying around.

I have no idea what an .iges file is. What program creates that? Can you save it as something else?

[David King]

"The Initial Graphics Exchange Specification (IGES) defines a neutral data format that allows the digital exchange of information among Computer Aided Design (CAD) systems." I think the suffix is .igs.

[David Schwab]

Guess it's not neutral enough! Can't CAD programs export EPS files? I have AutoCAD but haven't used it in a while....

Even a PDF should work, since it has vector information.

[jason lollar]

if you have seen a laser cutter just going back and forth thats rastering and its used for engraving only- its only one mode that the lasers I have can use. I had assumed they could all raster and vector cut
My new one will print off a PDF- you just cant manipulate the PDF on my machines. They are used to hand out to your crew so they can cut but not screw your drawing up
I would bet the reason someone has to redraw everything in corel is because whatever file format the drawing was originally made on doesnt have the right line weight. If you dont use a "hairline" the laser sees a wide line which it tries to raster. as the laser sees it A wide line is basically 10 or 20 hairlines overlaying each other- I had that problem years ago with deltacad where I couldnt specify as thin enough line so I had to redraw the straight lines- now all I have to do is weld nodes in corel in fact I just stumbled on a way to weld all the nodes of the perimiter at once- not sure how I did it, I hit a key accidentally so I am trying to revvreate it. You can also arrange the order everything is cut it so a strat top plate for instance- you make it so it cuts each hole from left to right then it cuts the perimiter- in corel thats just a matter of shift tab page up otherwise the laser will cut more randomly and will waste time jumping around- wears your belts and bearings down faster and slows down the job. Corel will do alot of things autocad either wont do or is clumsy to make it do- a cad program is far easier to make mechanical drawings with where you plot points using X Y coordinates