I am thinking on building a rotary chuck and implementing the rotary tube cutting for round and square/rectangle tube.
I am curious if anyone has pictures of their setup, and/or videos of it in action and drawing and setting it up in sheetcam. I would be VERY interested in seeing the process from start to finish. I have watched 1 video Les has on youtube, but i would like to see more to make sure it will work how i want it to before designating time/money to this upgrade.
Lots of what i would use if for is cutting gussets out of square tube so no bending is needed, and making notches in one end of a rectangle tube, moving the desired length and notching the other end, so when it falls off, it is notched and proper length. Currently, i am chopsawing the tubing to length and then placing it on the plasma table in a jig and notching each side one at a time. It would save me alot of time, and i could eliminate alot of stock of cut tubes as i should be easy, load a tube, load the gcode, press go, and i have my couple of tubes i need, instead of making abunch to make use of the setup time needed for the jig and aligning things, etc.
Please post links to youtube videos or whatever you have.
Well i guess i was too impatient and i beat anyone else posting. I just got it done and working. Still have some bugs to work out, and supports to finish and replace my trashed nozzle and electrode for better cut quality, and then i will take some more videos. But here is a link to a few if anyone else is interested.
LOL, really, that actually shocks me. I will post much better videos when i get it all working perfect and things finished up. I have a few other things to do in between playing with the new addition.
Well if anyone ends up being interested in one, maybe Ill have to put a few together, and get more of your rotary plugins sold.
Les, that video explaining a few things and showing the benefit of a rotary axis, that I mentioned i would put together for all your assistance, is now complete and being processed on my computer. It ended up being 20 mins long! Then i will upload it to YouTube and eventually my website. I am not a professional videographer, but i think it will be very helpful to some venturing into a 4th axis on a plasma/laser table and using sheetcam. I put your website and contact info at the end to point people towards you if they find it useful and don’t already have your program (or the plugin)
I will post the link here when it gets done uploading, and you can copy it or point people to it if needed.
I have a local fencing business intrigued and slightly interested in it for long tube sections if i can just get them talk into letting me build them a custom machine for it now.
That video is great! Thanks yo uvery much. I really like your setup. Your support system is really simple and effective. I have seen several designs for supporting square tube and your has to be the simplest and it looks like it works well.
The motion while cutting around corners looks very smooth. I have another cutomer who has problems with the machine slowing down a lot when cutting around the corners. Have you seen that problem?
The square tube support did take me awhile to think up. Several nights while laying in bed instead of sleeping. I didn’t like the methods that most systems used on a stationary chuck setup like mine. I wanted something that could support it underneath and allow cutting on top and wouldn’t have to be moved for every cut. I need to make another one so there is 2 for longer tube to support the end, and then after parts are cut off, the 2nd one is still there. I also have to find a higher temp material, as if there is alot of 60 amp cutting going on near it, it gets a little soft. That one was just made out of a piece of something i had laying around, you know midnight engineering.
My round tubing support didn’t make it in the video, but it is a simple 2 arm scissor mechanism with slots and a hand knob in the middle with bearings on the end. You set it to the right height right by the chuck by pulling the bearings up snug and tightening the knob, then slide it down were you need it. Works pretty slick.
Both are simple but effective.
As far as the corner slowing, no I do not think so. What is the gear ratio of his rotary axis and his velocity and accel in mach 3? Maybe the rotary axis is slower than the rest? Or a setting like constant velocity or linear/angular, etc is wrong? Not sure unless i was to dig into it or had his velocity and accel for his axises and cutting speed he is using for some calcuations. Or is he using a different post?
Brian, that was very interesting, thanks for sharing that with us. From the time I built my first CNC machine (a router machine), I have been fascinated with what can be done with CNC. I’ve since built a plasma table, and just recently added a plate marker to it. (I also recently added a laser to the router machine). Next addition I’ve been thinking about is the rotary tube set up that you just showed us, so your video was quite timely. You certainly opened my eyes to the fabrication of the rotary axis.
excellent I’m glad you liked it, I would actually be interested in what all you had to do with the laser cuz that’s not something I’ve done yet and would be kind of useful also how powerful and how thick can you cut or is it just for engravimg?
I think his 4th axis was lower geared than yours. I have a vague recollection that CV only works on XYZ and not any other axes, which would make XYZA moves jerky.
Have you considered wood for the support? Maybe a dense Birch ply would work. Wood can take reasonable temperatures. It actually takes quite a bit to set fire to a chunk of ply.
As far as laser cutting is concerned, Mach3 isn’t great at running a laser. It works fine for cutting but a lot of laser engraving is raster cut. The head scans back and forth at a constant speed and the laser fires as needed to build up the image. Mach3 doesn’t really have any way of turning the laser on and off without interrupting motion. SheetCam has a laser engraving plugin that can generate these raster toolpaths but I haven’t yet found a controller that will run them smoothly.
The lower gearing could be part of the problem, lots of people repurpose rotary tables that have worm gears, and thats too much reduction. As far as the CV on A axis, it could be, but i would be surprised. It does not appear that the CV is not working on mine, but i could be fooled.
I had not considered wood yet. It could be a possibility, however i like the plastic type like i made, only with a higher temp material, because i actually made it slightly undersized, so it has a snug grip on the material which also helps with slight inconsistencies from different tubing manufacturers.
For the laser, i would be more interested in using one for cutting, although if there is not a diy or option that doesn’t cost 50k, i can do without. it would just be nice for some applications, but plasma is good enough for the majority of what i do.
I have seen the type of engravers you are talking about, and Im not currently interested in them.
Brian, it’s a pretty low power laser that was originally in a DLP projector. Like you said, midnight engineering!. It’s got enough power to cut 1" foam, or 1/4" pvc. It has problems with clear materials. I mostly use it for engraving designs in wood. If I need a wider line I can just offset lines in the drawing program and go back and forth a few times. I mostly built it just to see if I could do it. Like I said, there are so many things you could do with CNC. My next project for the router table is to make up a plotter to draw up large drawings, etc. Perhaps a swivel knife would be a neat project. I’m a bit of a tool guy, and often the fun is in the building of a new tool. Now that you and Les have got most of the bugs out of the rotary cutting, that’ll have to be my next plasma table project.
For the plotter, i think i would disconnect the air to my scribe and clamp a sharpie to the mount, lol, instant large plotter.
If i could get a laser that would cut 1/8" or even 1/16" steel or aluminum, and maybe some engraving, that would be nice. I have not really looked into how expensive it would be for something like that, or for cutting thicker material.
I totally agree about the equipment building, that part i really enjoy and consider it fun work, and it brings added value to my small business. Once the initial CNC Control and table is built as well as understanding the gcode and other info that goes with it, i cant help but add other functions as it is a low cost and short time investment to add basically a whole new CNC capability.
I also have plans to add a small spindle to the z axis (easily installed and removable) to allow me to do light duty milling or router work.
I’ll have to try the laser out on some thin aluminum, just for grins. I really doubt it has enough power to do much, but what the heck. The laser is only 2000mW.
My original intent on building the plasma table was to use it for everything, but after a bit of research, it sounds like the plasma needs to be fast and light, and any contact type work needs to slow and heavy built. My router table is super strong, very overbuilt, using 5/8" aluminum for the gantry. (I found a sheet of it in the salvage yard.) In my defense, it was the first CNC table I had ever built. But it works pretty good for any milling type operation. It would never do as a milling machine, but I have used it for light duty aluminum type work.
So I have ended up with two CNC machines and a very crowded shop. Maybe my next project should be a shop expansion!
fast and light, yes and no. If you can build it fast and heavy, great. I understand this, but built mine heavy duty anyways and couldn’t be happier. I am however running dual 960oz in steppers at very close to their peak power with 50volts and 6amps each and another 960 for my X. I have 850 IPM Rapids and 75 Accel which i could probably push further, but that was plenty sufficient for me, as i was shooting for atleast 600. My positional accuracy is .00585 before micro, and .000585 after 10x microstepping. Plenty sufficient for anything i will want to do. I do some thinner gauge stuff, but mostly 1/8" through 1/2". I wouldn’t be using the table for any heavy duty milling, just light duty aluminum and plastics mainly. It actually holds better tolerances than my benchtop converted CNC mill with the way i designed it. I already have a switched AC socket on the control box for a simple router spindle, and solenoid air valve on the z for the scribe which i would T into with 2 valves and just turn on which ever output i needed, scribe or mist for router. I just havent gotten that far yet. I also trust it more than my benchtop mill.
Laser cutting metals needs a lot of power. Lasers for cutting metals are in the kilowatt range and are hugely expensive to buy and run. I tried cutting aluminium foil with my 40W laser and it didn’t even leave a mark.
