Argle-bargle! NEMA XX is just a mount size specification! They tend to be more powerful, and have a higher top end because of their size, but if you get a NEMA 23 pancake motor, and put it up against a monster 80mm NEMA 17…
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Sure, but a 80 mm NEMA 23 will have more power than a 80mm NEMA 17. And if you’re trying to shove around a big metal gantry with a 2kw spindle on it, you’ll need more torque.
It’s the same reason why the Eco-boost isn’t put into 1-ton trucks.
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I’ve wanted to build a JGRO since 2005, I had planed to use it to build a Joe’s 2006… That might be a few steps backwards at this point. 
It’s almost the same linear motion as the mpcnc as well. Just less elegant.
Yes. An 80mm NEMA 23 will have more power than an 80mm NEMA 17.
But what I was being nit-picky about was the sloppy shorthand of using just NEMA specs as an indication of motor strength, when it’s not. I also get annoyed when people use Kg for weight or lbs for mass… Yay for OCD! 
Sounds like a personal problem 
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One of many… 
I’ll just throw out my experience…
I have a mid-size mill (Grizzly G0704). I’ve done a fair bit of work in both steel and aluminum on it. It will eat aluminum for breakfast, and it does a reasonable job on steel (just have to watch that you don’t try to take too big of bite). It doesn’t compare to a Bridgeport but it is (IMHO) the perfect size mill for a hobbiest.
I wanted to get into CNC, so I started looking at my options… CNC the G0704, Build an OpenBuilds machine (like the WorkBee), get one of the small 4/5 axis machines, buy/build a mini-mill CNC… My goal was to cut out mounting plates and small 3D modeled parts from aluminum.
I ended up going the MPCNC route - with the expectation I could use it for mounting plates, but probably not 3D parts. I don’t think the stiffness is there in the MPCNC for true 3D contouring in metal - I could concede that this may be incorrect, but I still suspect that a ball-nose bit in aluminum on the MPCNC wouldn’t be a pretty sight to see, and I would bet dollars to donuts that 3D in steel isn’t feasible on this ‘class’ of machine.
I’m currently using the MPCNC to help build out a CNC retro-fit of a mini-mill (LittleMachineShop’s Sieg X2D model). That machine will likely be dedicated to 3D parts in aluminum and possibly 2D cutouts in steel plate - If it can manage 3D parts in steel that will be a bonus. But I feel like the general consensus is that (even though it is build from cast-iron) it doesn’t have the stiffness or mass to deal well with steel.
I am taking a very cost conscience approach to the mini-mill build and I will likely have $1500 in it before I’m done. That does not include any tooling - because with an R8 spindle I will be able to share all tooling from my existing mill. If someone where starting from scratch they would be looking at probably another $1K just to get ‘up to speed’ on tooling. So that is a very far cry from the (let’s call it) $400 I have in the MPCNC.
And at the end of the day I’m really realizing that the MPCNC and a CNC mill are really completely different machines targeting completely different sets of work.
Oh well, enough rambling…
I think the “next logical step” after the MPCNC really depends on what you’re planning to do next. If it’s really 3D metal, then I suspect nothing in the flatbed category is the right answer…
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I don’t even know what I would do with 3d metal. I’ll only have brackets and linkages for my car projects, likely my buddies, too, once word gets around. Everything my wife has thought of so far is strictly 2d, as well.
I retired recently and have determined that I need long-term projects that I can work toward to keep the old noodle active. My current long-term project is to build something akin to the MIT mini-cheetah:
not an exact copy, but something in that class of robot. So I expect to be needing multiple copies of fiddly little 3D parts… hence the delving into CNC…
I need that! I bet that thing doesn’t pee on the throw rug!
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It’ll probably leak electrons.
The problem is when they vent their lithium packs. You thought the cat spraying on the couch was a mess…
Just don’t play cards with them. They are all cheetahs.
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Our city sent out a reminder to not throw items with rechargeable batteries in the trash. They had two dump truck fires after Christmas due to batteries exploding.
I dunno, I’ve been beating up my MPCNC pretty badly over the last little while and looking at that little guy, I feel an MPCNC could do it.
I haven’t read the specs, for all I know it’s made of titanium, but I’d bet you could clone him in Aluminum.
Has anyone built a MPCNC waterjet cutter? I think I’ve seen a youtube video where someone coupled a jetwash machine to a waterjet nozzle and was able to cut steel. I’ve no idea how it would compare to a plasma cutter for practicality or precision.
I don’t think I’ve seen that yet. Not sure how fast they can cut, but “should” be just as accurate as a plasma. Less warpage as well.
There was a thread right after that video got popular. Turns out the critical parts to the system are generally very expensive and difficult to get.
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If memory serves, there was also an issue with not being able to recycle the cutting media, so it was painfully expensive to run for any length of time…
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