Hello everyone. I have a need to cut cloth Material (Textiles) The width of the fabric is 60" and I want to be able to roll out the material 5 or more feet. I plan to use a J Tech 2.8 laser that weights 1.2 LBS. The only DIY kit I can find is from http://buildyourcnc.com but this is wood and they have 5' x 10' and 6' x 12' builds. I would like to build one out of Aluminum or metal. I have the skills build any table to support the cut table. I need help with what I need and what will work for the size Laser Table I need. Any help would be great. Shannon
Here is my plan. T0 build a 1500mm x 1500mm to start with. I do not believe I need to control the Z axis since this will be a laser cutting material (clothe Textile). So I can have the laser at a fixed height going across the Y axis. This will make for a light plate going across the Y axis and little deflection. I plan to build the Y axis with 3 20mm x 60mm x 1500. This will be for strength and I can put bolts through them to help stiffing up the Y axis. Using OX ΒΌ steel plates to connect the X and the Y axis. 1500 on the Y axis is going to be close. If I need to extend out I will make the 3 20mm x 60mm V Slots longer with dowels to connect them and having the seams in different places, then bolting them together. This sounds like a solid plan.
Solid being the operative word there. Actually, it sounds a bit too solid as in you are way overbuilding this. Laser cutters don't use brute force like regular cnc machines. The material being cut doesn't fight back like it does on a regular cnc system. Laser cutters mainly need speed and agility, not brute strength. Look at some of the other builds and you'll note how lightly they are framed. Granted, you're using a heavier laser and wanting to span a greater distance so yours will need to be a bit stouter but you'll find excessive framing is just extra weight you have to repeatedly move around. Personally, if I were looking to build a 5'x5' system I'd start with three 6' lengths of 2 x 1-1/2 x 1/8" aluminum extrusion for the supporting frame and use V-slot merely as runners for the system with 20x20 extrusions affixed to the side support rails and butted lengths of 20x40 on the gantry to support the laser head carriage. The overall weight would easily be low enough to where gt3 belts and basic nema 23 steppers could be used. You may also be able to use the new 40x40 sections rather than the extrusion noted above but as I haven't worked with it yet, I really can't say. You will however run into length issues as the pieces max out at 59" and I haven't seen any truly convincing splicing methods yet to where you would have a usable, longer length. The only other recommendation I would make on a system of this size would be to not skimp on the electrical aspects. Longer wires tend to have more issues with signal interference and power loss. There are several experts on the forum who can give you a better idea of the problems and what is at stake here. (no, I'm not one of them)
I just posted some pictures from Sketchup of my thoughts on how o build this. I am horrible at sketchup so they are just a way to show what I am thinking. My Large Table Build.
Looks like a good start. I've been thinking through some splices that may help you get to the 64" you need but won't have time to sketch them until the weekend.
Thanks Rick. That is no worry. This is the research stage and I am trying to make the purchase of parts in about 2 weeks. I also have a good friend that is a machinist. I sent him the information with links and my plans he is working up some magic to. I am planning on using OX side Gantry Plates I believe this will be light enough to use G3 belt.
If your machinist friend is also a fabricator, I'd have him rustle up some kind of lightweight, triangulated truss gantry, from which you can sling a cut-off piece of regular 1500mm 2020 V-Slot. Alternatively, have the entire gantry be a vertically-oriented torsion box- two sheets of 1/8" alu sheet, maybe 6" wide, with some kind of honeycomb (or slotted square grid, etc) about 3/4" thick epoxied between them. You need something lightweight enough to be able to move with relatively little power and stop with minimal momentum, as well as be rigid enough to be able to stop and accelerate without flexing. the 4040 hollow extrusion would probably be sufficient, but it doesn't come large enough. Of course, you could simply use that as the "core" of your beam, and attach a longer piece of V-Slot to it which is your actual linear rail, along with some larger brackets on each side to reach in and connect to the 4040. That would be the simplest, though perhaps not the lightest or most elegant, solution.
Thanks for the reply. U have found 1800mm long Markerslide. I think putting 2 of these together will be perfect. This should give me close to 64" of work space.
I am getting ready to buy the parts I need and start building. I have a few questions. Eccentric Spacer 1/4 are out of stock. Will the 6mm work in the place? They are close. For this build which stepper 23 motors should I use? High Torque?
A suggestion for adding length to the 40x40 sections. Trim a couple of 75mm lengths and drill the holes out to 5mm, tap the ends of the main 1500mm length, and run the screws through. The ends of the extrusions need to be perfectly square but having a friend with a machine shop solves this. This connection will be more than strong enough for your purposes and will take you up to about 65" usable.
If you get stuck for a source of 100mm M5 screws, Bolt Depot has them. (Assuming you are in the US of course. Finding them anywhere else in the world should not be an issue.)
Next big question. I have software that will output DXF files that my laser cutter will need to use. What software can I use on a Raspberry Pi for this? I am looking at Laser Web
