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@gerrymoore perhaps?There was one member who did this, I seem to recall he had no end of grief but got it working eventually... I forget who it was
Piece of cake! 
, got there eventually!
Ned is doing one now, it really depends on why, How much and what do you want to produce?
if you like challenges and the journey is better than arriving then knock yourself out and dive in.
Adrian
, got there eventually!Ned is doing one now, it really depends on why, How much and what do you want to produce?
if you like challenges and the journey is better than arriving then knock yourself out and dive in.
Adrian
decca
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I've known a few people make cnc things (not just plasma).
The ones who simply wanted a finished tool to use complained about "endless problems".
The ones who did the build for itself (having a tool at the end of it was almost optional) had the same issues, but called them "interesting challenges" instead
I do see it as a challenge, no experience in electrickery so ideally a kit with the correctly spect motors and software would be good. There's a lot on eBay but need to research what NEMA means and what I need. Just started looking but it is going to be my next project .
In that case I would buy complete, sorry to say that but, without an understanding of what where and why, think down the lines of what you wish to do at the end, commercial work, large art work, small art work etc. Then take a step back look at some manuals on line at various cutters and decide what make model you need to cut what you want. Look at the specs of the cutters, input volts and currents, do you have 3 phase, do you have a limited supply, home or 2000, sq-ft unit type locations. Think of size and CFM of compressor you will need, start sitting down and putting costs together and see if it matches your budget.
Ned for example is looking at 8 ft capabilities and middle range thickness, look at and ask Hood for his thoughts, he probably is solely commercial so 6 to 12mm range, (some arty stuff to play with).
Cutters can be top of the range Hypertherms, Tecarc, Lincoln etc down to Chinese cut 100 for commercial to very cheep, but blown it a few times cut 40.
If I was thinking in anyway commercial it would be a ready made, with support from a manufacturer, possibly swiftcut in the UK would be a choice it is not so much the machine it self but software support.
Go on to Plasmaspider forum and dig around there, mostly American based but you will find posts specifically regards plasma, there is a suppliers section.
Anyway not trying to put you off the idea just consider what you want it for. But it is fun when it works.
Adrian
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T0rnado69
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i plan to make a table in the future and often read up on another two forums for cnc stuff..
mycncuk
and this guy in the usa did a good job on building a table
but like others have said....... too much going on right now to start a long project like this.
mycncuk
and this guy in the usa did a good job on building a table
but like others have said....... too much going on right now to start a long project like this.
henry Kadzielski
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Anyway not trying to put you off the idea just consider what you want it for. But it is fun when it works.
I can confirm 'IT IS FUN WHEN IT WORKS'. I agree with all the above posts and you don't really need and indepth electrical knowledge, but some is very usefull. I completed mine about two years ago and it was an absolute achievement watching it go. It was a far more daunting and frightening prospect watching it cut something. The hardware is the simplest to get your head around, I built mine in three weeks with no plans. Just started at the smallest component 'the Z drive' and went from there. Integration of the electronics package (control system and software) is what rattled me and I nearly poured petrol on mine several times. The control package (electronics, drive systems and software) all came from the states, as I wanted the minimal problems in getting one going. If 'everything' is able to communicate with each other and run together, then it is just a matter of plugging it all together and it goes
Nothing is quite that simple as the combinations of drives are endless.
You need to decide what it is that you really want and or need. See what is out there in the market in turn key systems and of you feel you can build one then go for it. Remember your build needs to be accurate and you need to be annual in doing so. I build my machine to plasma cut, route timber, plastics and flat bed mill alli, so very specific requirements in a build. So far it has played the game and the only problem I have had was a faulty operator unit, the organic controller. I know enough in the software to get by, but not enough to get the maximum out of the package, but it has all worked for me. Once the job is done, then you move onto the next. There isn't time to 'how can we make this better' if there was large production runs then I would look at everything again, but most of my stuff is one off's, two's and possibly three.
Tom Orrow L
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We've just bought ourselves a demo CNC table for the shop which I'm looking forward to using. A customer of ours has actually made a new venture creating and selling them.. kit form or complete and he's got CE marking etc.. brilliant bits of kit. I'd be happy to put you in touch with him if that's any good?
julianf
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I made the machine that the part in my avatar was cut on....
That was years back. Things have moved on. For the electronics, you can now go to one UK based retailer, click a few things, and get a package in the mail. No scratching around far east breakers on eBay and the like.... So the electronics really are not a concern.
What you still need to work with are the linear parts. If you're doing plasma then I'm thinking ball screw is expensive overkill. So that makes things cheaper.
The rest is just engineering. And buying the right plasma torch.
I'd build a plasma table if I had the space or the application. But I have neither.
...but if I did, I'd have no qualms about diying one.
That was years back. Things have moved on. For the electronics, you can now go to one UK based retailer, click a few things, and get a package in the mail. No scratching around far east breakers on eBay and the like.... So the electronics really are not a concern.
What you still need to work with are the linear parts. If you're doing plasma then I'm thinking ball screw is expensive overkill. So that makes things cheaper.
The rest is just engineering. And buying the right plasma torch.
I'd build a plasma table if I had the space or the application. But I have neither.
...but if I did, I'd have no qualms about diying one.
Morning, just a few of my thoughts on accuracy after reading @henry Kadzielski 's response, these are my thoughts and that only that, I am not getting into argumentative mode and disagreeing with Henry about designs.
When routing and milling you design with Rigidity and accuracy in mind. There is side loading on the the cutters, power is needed to push the cutter through the material at speeds and you may well wish to have accuracy down in the region of 0.05mm (0.002") depending on the final application of what you are cutting. Plasma is not accurate to that degree because of the process. Have a read of this manufacturers paper.
http://torchmate.com/white-papers/The-Accuracy-of-Plasma-ARC.
Also when milling/routing the travel speeds could be mid to high, but I believe not as high as using say a 40 amp cutter on 22 gauge sheet. where best results for 40 amp cutters could be over 8 metres per minute travel speeds.
http://torchmate.com/uploads/downloads/metric-measures/FineCutwithLowSpeed03_12.pdf
There is a general direct correlation of speed and location accuracy in the driver units, steppers and servos and is down to step distance per pulse, the smaller it is then the slower the top end speed is as the motors will have a finite rotational speed.
Because the plasma is not as accurate a cut process the step distance per pulse is typically larger than for milling or routing and allows for a higher travel speed, there is also no side loading on a plasma torch, the issue is more the initial inertia of gantries/carriages to get over when trying to move at high speeds.
All the above is really just going off how my brain works and what I have picked up as I go along.
I feel chuffed when I cut out parts like the tea-light and name monograms. My gear is really down at the low end of the scale.
Adrian
When routing and milling you design with Rigidity and accuracy in mind. There is side loading on the the cutters, power is needed to push the cutter through the material at speeds and you may well wish to have accuracy down in the region of 0.05mm (0.002") depending on the final application of what you are cutting. Plasma is not accurate to that degree because of the process. Have a read of this manufacturers paper.
http://torchmate.com/white-papers/The-Accuracy-of-Plasma-ARC.
Also when milling/routing the travel speeds could be mid to high, but I believe not as high as using say a 40 amp cutter on 22 gauge sheet. where best results for 40 amp cutters could be over 8 metres per minute travel speeds.
http://torchmate.com/uploads/downloads/metric-measures/FineCutwithLowSpeed03_12.pdf
There is a general direct correlation of speed and location accuracy in the driver units, steppers and servos and is down to step distance per pulse, the smaller it is then the slower the top end speed is as the motors will have a finite rotational speed.
Because the plasma is not as accurate a cut process the step distance per pulse is typically larger than for milling or routing and allows for a higher travel speed, there is also no side loading on a plasma torch, the issue is more the initial inertia of gantries/carriages to get over when trying to move at high speeds.
All the above is really just going off how my brain works and what I have picked up as I go along.
I feel chuffed when I cut out parts like the tea-light and name monograms. My gear is really down at the low end of the scale.
Adrian
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Wedg1e
They call me Mr. Bodge-angles
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My thruppence-ha'penny, for what it's worth...
for a while I've fancied building a multi-purpose CNC rig that could have interchangeable cutting heads, so plasma, router, perhaps waterjet as I hear it's now being made affordably - and even 3D printing with an extruder head. Of course you'd have to engineer it for the highest cutting force which would be the router spindle, the other techniques don't have to resist the side loads.
As it happens I got landed with the design and engineering of a 3-axis inspection machine; it uses an array of ultrasonic and eddy current probes to scan the surface of up to 10 rotating bars in a tank of water, the bars being anywhere up to 6m long.
As there's minimal contact friction between the probes and the bars we used rack and pinion for the (7m long!) X-axis. R&P has an inevitable small amount of lash between the teeth but even so we found it would attain better than 0.2mm positional repeatability over 6m. Using CNC4U and Zapp automation as suppliers we propelled the carriage along the X-axis on 20mm HiWin rails using an 8Nm servo-stepper and (IIRC) 1.5MOD R&P.
The Y-axis carriage rides on the same rails and uses the same R&P but is propelled by a NEMA23 driving through a reduction gearbox (we hadn't a clue how powerful the steppers would be so thought the gearbox would give us an advantage; the resultant torque is outstanding but you can't then traverse at high speed unless you use a long ramp-up on the driver pulses) while the Z-axis uses the same HiWin rail, a 5mm pitch ballscrew and a NEMA 23 driving it direct (through a coupling to allow for assembly tolerances :cough:
).
So my suggestion for an economy plasma would be to use rack & pinion as the slight gear lash won't add much error; use a short ballscrew as the Z-axis to lift the torch off the work (ballscrews are expensive) and if you can't build on nice flat machined surfaces then use supported round rail rather than the square HiWin stuff as the round rail carriages can self-align better if the rails aren't both perpendicular to the mounting surface.
And however big you think you need the rail to be, get the next one up
And another thing: if you do use ballscrews, make sure you shroud them from flying sparks or cutter debris.
for a while I've fancied building a multi-purpose CNC rig that could have interchangeable cutting heads, so plasma, router, perhaps waterjet as I hear it's now being made affordably - and even 3D printing with an extruder head. Of course you'd have to engineer it for the highest cutting force which would be the router spindle, the other techniques don't have to resist the side loads.
As it happens I got landed with the design and engineering of a 3-axis inspection machine; it uses an array of ultrasonic and eddy current probes to scan the surface of up to 10 rotating bars in a tank of water, the bars being anywhere up to 6m long.
As there's minimal contact friction between the probes and the bars we used rack and pinion for the (7m long!) X-axis. R&P has an inevitable small amount of lash between the teeth but even so we found it would attain better than 0.2mm positional repeatability over 6m. Using CNC4U and Zapp automation as suppliers we propelled the carriage along the X-axis on 20mm HiWin rails using an 8Nm servo-stepper and (IIRC) 1.5MOD R&P.
The Y-axis carriage rides on the same rails and uses the same R&P but is propelled by a NEMA23 driving through a reduction gearbox (we hadn't a clue how powerful the steppers would be so thought the gearbox would give us an advantage; the resultant torque is outstanding but you can't then traverse at high speed unless you use a long ramp-up on the driver pulses) while the Z-axis uses the same HiWin rail, a 5mm pitch ballscrew and a NEMA 23 driving it direct (through a coupling to allow for assembly tolerances :cough:
).So my suggestion for an economy plasma would be to use rack & pinion as the slight gear lash won't add much error; use a short ballscrew as the Z-axis to lift the torch off the work (ballscrews are expensive) and if you can't build on nice flat machined surfaces then use supported round rail rather than the square HiWin stuff as the round rail carriages can self-align better if the rails aren't both perpendicular to the mounting surface.
And however big you think you need the rail to be, get the next one up
And another thing: if you do use ballscrews, make sure you shroud them from flying sparks or cutter debris.
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Depends if the goal is to build a machine or get a CNC plasma I guess and how much time you have to figure out things like signals to the plasma cutter.
I just got a swift-cut Swifty in. Yet to have a play and doubt I'll get chance until after schweissen-schneiden but seems a funky little machine.
I just got a swift-cut Swifty in. Yet to have a play and doubt I'll get chance until after schweissen-schneiden but seems a funky little machine.
henry Kadzielski
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Good afternoon Adrian. I couldn't agree more, probably didn't word it correctly.
The analogy that has been used is routers and mills are like draft horses and a plasma is like a Ferrari. Like you said there is no side loading with a plasma, as a result a very different set of build parameters. A plasma need very quick change of direction 'acceleration' especially on the thinner materials, whereas the mill will require accuracy 'and you would want better than .05mm' rigidity and the torque to push the tool through the job. I have routed at 4.5m/min and could have gone faster using a 6mm cutter on MDF with a 6mm cut, however I normally cut thicker materials with the plasma so, so far have not run much speed in the table. I have tested mine to 10/min, it was quite frightening at that speed. I have 10:1 reduction gearboxes on the X and Y axis with servo motors on all drives. So by some sort of luck than good management got it all to do what I required.
By the way all my motors are NEMA 34
Morning all, having been down this road and building my own table believe me that's the easiest bit getting your head around the different software that's needed to run these machines is a hole different ball game but having said that if l can do it so can you if needing help just let me know.
Wedg1e
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Laser, that was the other technique I had in mind
I'm told you can buy quite poky lasers for not much now, my son-in-law has a desktop Chinese-made think that will whizz through 3mm ply and plastics but it's limited to an A4 sheet size.
I'm told you can buy quite poky lasers for not much now, my son-in-law has a desktop Chinese-made think that will whizz through 3mm ply and plastics but it's limited to an A4 sheet size.
Why?
Some of the ones I have seen in kit form use ERW tube and sit them on edge similar to your idea with angle. You could flap disk it down if required, but, you said it is smooth, how many thou do you think it will deviate the cutter with the mill scale?
Adrian
decca
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Have a video of it.
It's a metric gauge the needle wobbles about a bit because of the scale but I understand for a plasma table it's acceptable.
Luke
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A chap I know designed a complete machine to be easy to make, it uses the same principle.
https://forums.lr4x4.com/topic/92367-cnc-plasma-group-build/?tab=comments#comment-798848
https://forums.lr4x4.com/topic/92367-cnc-plasma-group-build/?tab=comments#comment-798848
