# Any hobbyists using milling robots?



## strantor (Feb 22, 2017)

This is probably a dumb question, but I'll ask anyway...

Robots can mill steel apparently, as per this video:






And now that we have a mature robo-manufacturing industry, you can find used/refurbished industrial robotic systems for an astonishingly low price, for example:

1997 Fanuc S420IW for $3,800. Refurbished, complete, 100% working, and looks great.

http://www.ebay.com/itm/Fanuc-Robot...8140669&pid=100005&rk=2&rkt=6&sd=271770553090



Any reason why you couldn't put a milling head on that thing and have the world's most versatile milling (and plasma cutting, and welding, and painting, and dog walking, and hamburger cooking) machine, all for less than the price of a 3-axis CNC mill? Why not?

Like I said, dumb question; I am not all that knowledgeable about milling, and I know even less about robots. But I'd like to know what would stand in one's way of doing this. Is your typical 1997 model eBay robot not rigid enough for milling? is there no affordable software available to make it happen?


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## T Bredehoft (Feb 22, 2017)

At a raw guess, software and the stuff to run it on may exceed cost of the robot. 
On second thought. it appears to have some control system with it.  

I'm not at all sure it would be rigid enough for what we consider normal milling in metal. Working soft wood or plastic might be feasible.


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## markso125 (Mar 28, 2017)

I ran those robots for a few years when I was coating stainless pistons with Tungsten carbide, they were very temperamental and not that accurate because of rigidity. We would not have been able to use them as much as we did if we didn't have the option of changing parameters every few parts to match the runs.


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## cjtoombs (Mar 28, 2017)

I think those robots would be good for manufacturing, where you could set them up, dial them in and let them do the same thing over and over.  I concur with the comment above, I think the software for generating the movement for those is VERY expensive.  When I say VERY expensive, I'm talking like 10s of thousands of dollars per year license fees.  They have to do kinematic calculations.  For a CNC mill, there is only one position it can be in in order to position a tool at an XYZ or even AB location, for a robot, there are many combinations that can result in the same position.


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## Metal (Mar 30, 2017)

They are really neat
But not knowing how they work and putting one in your garage is just asking to have holes punched in the walls, ceiling, or having you killed
They are much, much more dangerous than a mill since they have a huge working area that you have to more or less enter to get your part.


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## markso125 (Mar 30, 2017)

Probably the best use we have for robots in cnc manufacturing is loading and unloading of cnc machines. The machine tools maintain the rigidity and the correct tooling and are a lot more efficient then robots currently are at machining.






In the near future we will probably be doing the majority of machine work with metal deposition machining (also known as metal sintering) instead of metal removal and possibly using robots to finish parts


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## markso125 (Mar 30, 2017)

For anyone that is curious about sintering here you go


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## strantor (Mar 30, 2017)

I have a 3D printer (plastics) and have been keeping loose tabs on the hobbyist 3D printing world. Some have been doing some exciting stuff with lasers and getting closer to viable in-home 3D metal sintering machines. I will let them iron out all the kinks before I take the plunge.


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## Metal (Mar 31, 2017)

strantor said:


> I have a 3D printer (plastics) and have been keeping loose tabs on the hobbyist 3D printing world. Some have been doing some exciting stuff with lasers and getting closer to viable in-home 3D metal sintering machines. I will let them iron out all the kinks before I take the plunge.



Note that the 3d printing world is full of total baloney.
I've been into it for a while, and people constantly make claims which are physically impossible, regularly, and folks just nod and smile.


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## JimDawson (Mar 31, 2017)

I'm not aware of any hobbyists using milling robots, but I do know of one local company that does specialized woodworking that uses a machine like that.  The work is mounted to a rotary table, and the router spindle is attached to a heavy robot arm.  I think the work envelope is about an 8 foot cube, maybe a bit larger.

You should be able to machine steel if the system is stable enough.  The CAM software to generate 6 or 8 axis tool paths CAM might be a bit pricy.  I think MasterCAM can do it with the proper plugins. ~$20,000 per seat.  Thinking about the G-code makes my head hurt.  The CNC software should not be terribly expensive, Mach3 will run 6 axis.


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## strantor (Mar 31, 2017)

Metal said:


> Note that the 3d printing world is full of total baloney.
> I've been into it for a while, and people constantly make claims which are physically impossible, regularly, and folks just nod and smile.



I'm not sure what fallacious claims you're referring to. I'm not putting up any defense, just I haven't seen any snake oil for sale.
Last time I read about hobby 3D metal printing they had some lasers pointed at metal dust, and were fusing it together. Didn't look earth shattering, and isn't what I'd call "3D printing" but there was some progress.

I can maybe relate, but what I've seen is more a general lack of knowledge and information than fabrication of information. Maybe that has improved (or gotten worse, if that's what you're describing). 

I initially started down this 3D printing and machining road in pursuit of making DIY prosthetic limbs. I wanted to make a hand for my father who is an amputee. I tried to find out before purchasing a 3D printer if 3D printed parts are strong enough to make a viable prosthetic. Nobody could give me a straight answer. I was appalled to find that at that time (2013) there was no standardized strength test to compare different polymers and processes. So I just jumped in and bought one, developed my own standardized test, and started to compare various polymers available. I tried to spread the word about my test and see if people could beat my numbers; maybe it would reveal common traits of good processes. Nobody took the bait. Nobody seemed to care. Everyone seemed content to print out a chess rook, smash it with a hammer or run it over with a car, and call it ambiguously "strong." Not good enough for me.

Ultimately I determined that 3D extruded polymer printing process cannot produce a viable prosthetic. I check back in occasionally to see what advancements have been made, but but so far I have not seen anything promising enough to give it another shot. There are some new polymers out there but I haven't seen them subjected to scientific testing that would indicate they have any better layer-layer bonding than anything else. Apparently still nobody cares about this, and for the life of me I can't figure out why!

For now I am convinced the only way to make dimensionally stable parts is to machine them out of solids.


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## Metal (Apr 26, 2017)

strantor said:


> I'm not sure what fallacious claims you're referring to. I'm not putting up any defense, just I haven't seen any snake oil for sale.
> Last time I read about hobby 3D metal printing they had some lasers pointed at metal dust, and were fusing it together. Didn't look earth shattering, and isn't what I'd call "3D printing" but there was some progress.
> 
> I can maybe relate, but what I've seen is more a general lack of knowledge and information than fabrication of information. Maybe that has improved (or gotten worse, if that's what you're describing).
> ...



Yeah that sounds about right

What I was typically talking about was "my printer is accurate to 10 microns because I looped my belts around this thing!" and stuff like that

dimensional stability is a huge problem for printers because the infill patterns all effect the outer layers unpredictably as the plastic cools.

I've made combat robot parts out of taulman alloy910 and it seems very reasonably strong and stable but I never did much testing.


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## cjtoombs (Apr 26, 2017)

I suspect the reason that no one is doing any real engineering (materials testing, etc) is that no one is using them for engineered applications.  What I've seen in my industry is using them for fit checks for parts with long lead times and pass around and display models.  I've also seen them used a lot by hobbyists for art and small functional products that won't kill someone if they fail.  The problem industrially is that for the quantities normally needed for consumer products, injection molding is much, much, much cheaper and faster than 3D printing plastic parts.


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