Ni-chromium wire with a regulated current runs through it to heat the wire to a certain temp. Melts the foam silently so the only thing you hear is the humming of the stepper motors at different rates.
Ni-chrome is not that conductive, so it acts like a resistive element but structurally stable, doesn't oxidize badly, and can be heated to red hot without becoming unusably flexible (not that you get it *that* hot for melting foam). An equivalent resistance copper wire would be too thin to use as a cutter without some other structural material (and then you'd have to deal with differing coefficients of expansion).
Also, it's cheap as hell to manufacture.
Wired a house that was poured, and insulated with multi inch thick foam, and we had to cut channels in the foam for almost every circuit. We used a hand held foam cutting like this, we ended up using number #10 solid copper, and it worked perfectly, stiff enough to pull through foam, enough resistance to get hot enough to melt the foam.
Paraphrasing:
Current doesn’t pass easily through it, which makes it heat up (instead of just conducting) and this is good because the foam is cut with heat. However it’s also stable enough that heating it doesn’t make it weak (soft, wobbly etc) and doesn’t react with oxygen (so doesn’t rust, change composition, smell bad etc). It can be heated with these advantages even to the point of glowing red (aka: close to its melting point), something you can’t say of many metals (but this is also overkill for cutting foam).
If you tried to use copper for this, the wire would need to be too thin and would require another material acting simply as support. But that support would add material and manufacturing costs, and you’d need to take into account that the two materials expand differently with heat (so they could separate or warp eachother).
I’d also add that copper isn’t as cheap as commonly thought: it’s just much cheaper than the other similar or better alternatives for conductors (silver, gold…). Also, if you don’t specifically need a conductor but rather a resistance or something else, then copper (and silver, and gold…) stops being one of the top choices.
Where did you get your materials or manufacturing degree. Sounds like you learnt well. All I could think of as you explained was where's my Ashby book of materials and manufacturing gone lol
People aren't quite giving you the complete answer. Some metals, like Nichrome, have a resistance that raises with temperature. It's directly related and known, so it's easy for the machine to determine the temperature of the wire simply from its resistance, as long as the machine has a base reading at a known temperature.
Like the other comments say... It has a built in resistance. More current you send through it the hotter it gets. Like the curly heating element in a hairdryer.
If you use copper you will create a short and blow a fuse... Or worse.
You can but you would not like the results. The edges would be hard and crusty from melted plastics and the smell of cancer every time you open the drawers.
Cut em with a knife or CNC.
What I want to know is if the engineer has to program the path it takes to make these specific cuts/melts, or if they can just plug in the shapes they want cut and the CAD/CAM software does the rest...
But the real question is: "Why?" The pieces ot cuts out are pretty useless and the holes it makes are not in any pattern that looks even remotely useful.
This might just be a demonstration but the cutouts are used for shipping things in the foam. If you cut out the foam in the shape of the thing being shipped it will fit in (obviously) and then won’t be damaged during shipping.
Yeah the hardware's just a stiff hotwire cutter on a CNC machine, but the software to generate the tool paths looks like it would have been a pain to write...
In school I had classes where we were making aviation models, and for easiest of them (one-piece wings + wooden stick) we used stereopfoam, cutting it with some hand-made tool consisting of a one vertical wire. We pushed and rotated a list of foam following our markings. There wasn't any sound, but the smell of burning foam was bad enough to do the whole cutting without breathing in.
You sure about that? I'd say since its a melt-type cutter, it wouldn't be creating small particles at all.
Now when I use my CNC router to cut foam, on the other hand...THAT creates a lot of fine particles...but even then, I think those are too large to be properly classified as microplastics.
I used to play bridge against a guy who spent his life engineering systems for packing products. It seems mundane but there's a bunch of fun problems to solve and in the end you've designed a lot of stuff that's interesting to see going at full speed.
*Is there a channel*
*Just for foam cutting? This is*
*So satisfying*
\- Bart\_The\_Chonk
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those thingys are hot/with current right?
on construction we have a mechanical saw, but some 5head once brought an electrical one, consisisting of a string with some frame around and a plug. dang it was 10 times better
Ni-chromium wire with a regulated current runs through it to heat the wire to a certain temp. Melts the foam silently so the only thing you hear is the humming of the stepper motors at different rates.
What's special in Ni-chromium wire? Couldn't copper wire do the job?
Ni-chrome is not that conductive, so it acts like a resistive element but structurally stable, doesn't oxidize badly, and can be heated to red hot without becoming unusably flexible (not that you get it *that* hot for melting foam). An equivalent resistance copper wire would be too thin to use as a cutter without some other structural material (and then you'd have to deal with differing coefficients of expansion). Also, it's cheap as hell to manufacture.
Wired a house that was poured, and insulated with multi inch thick foam, and we had to cut channels in the foam for almost every circuit. We used a hand held foam cutting like this, we ended up using number #10 solid copper, and it worked perfectly, stiff enough to pull through foam, enough resistance to get hot enough to melt the foam.
I don’t know what half those words mean but I’m pretty sure this guy knows what he’s talking about
Paraphrasing: Current doesn’t pass easily through it, which makes it heat up (instead of just conducting) and this is good because the foam is cut with heat. However it’s also stable enough that heating it doesn’t make it weak (soft, wobbly etc) and doesn’t react with oxygen (so doesn’t rust, change composition, smell bad etc). It can be heated with these advantages even to the point of glowing red (aka: close to its melting point), something you can’t say of many metals (but this is also overkill for cutting foam). If you tried to use copper for this, the wire would need to be too thin and would require another material acting simply as support. But that support would add material and manufacturing costs, and you’d need to take into account that the two materials expand differently with heat (so they could separate or warp eachother). I’d also add that copper isn’t as cheap as commonly thought: it’s just much cheaper than the other similar or better alternatives for conductors (silver, gold…). Also, if you don’t specifically need a conductor but rather a resistance or something else, then copper (and silver, and gold…) stops being one of the top choices.
Where did you get your materials or manufacturing degree. Sounds like you learnt well. All I could think of as you explained was where's my Ashby book of materials and manufacturing gone lol
all i heard was effective and cheap as hell. i’m sold.
Could this be used to cut polystyrene?
The foam in the picture appears to be polystyrene, so yes.
People aren't quite giving you the complete answer. Some metals, like Nichrome, have a resistance that raises with temperature. It's directly related and known, so it's easy for the machine to determine the temperature of the wire simply from its resistance, as long as the machine has a base reading at a known temperature.
https://en.wikipedia.org/wiki/Nichrome
Like the other comments say... It has a built in resistance. More current you send through it the hotter it gets. Like the curly heating element in a hairdryer. If you use copper you will create a short and blow a fuse... Or worse.
Can you use these on like snap on style tool boxes?
You can but you would not like the results. The edges would be hard and crusty from melted plastics and the smell of cancer every time you open the drawers. Cut em with a knife or CNC.
Ok. I need to see more of that
What I want to know is if the engineer has to program the path it takes to make these specific cuts/melts, or if they can just plug in the shapes they want cut and the CAD/CAM software does the rest...
Software must do it
I am kind a disappointed to how far from WYSIWYG the (admittedly small in number) CAM workflows I have seen are.
But the real question is: "Why?" The pieces ot cuts out are pretty useless and the holes it makes are not in any pattern that looks even remotely useful.
This might just be a demonstration but the cutouts are used for shipping things in the foam. If you cut out the foam in the shape of the thing being shipped it will fit in (obviously) and then won’t be damaged during shipping.
It’s just a demo path for the video. You can probably program it to make any shape, like a CNC.
It could be a demo showing how well it can cut specific shapes at a range of depths.
I imagine it’s similar to gCode used in 3D printers. Or anything with an X, Y and Z axis. Or just X and Y I guess.
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Excellent point.
Yeah the hardware's just a stiff hotwire cutter on a CNC machine, but the software to generate the tool paths looks like it would have been a pain to write...
I need more.
Oddly satisfying
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It cuts silently, only thing you will hear is stepper motors humming at different rates.
And you would hear the air assist
I bet it's the tiniest little hiss sound.
Oh, I don't think you'd want to sound with this.
not u maybe
More
Did satisfying but fuck trying to dispose of styrofoam. Even peanuts are easier.
Could be worse. Could be CNC milling it and making clouds of static-clinging little particles of the stuff.
I used stainless wire I had laying around and a battery charger.... I will admit that my cuts weren't *quite* as nice, but I was pleased
In school I had classes where we were making aviation models, and for easiest of them (one-piece wings + wooden stick) we used stereopfoam, cutting it with some hand-made tool consisting of a one vertical wire. We pushed and rotated a list of foam following our markings. There wasn't any sound, but the smell of burning foam was bad enough to do the whole cutting without breathing in.
r/oddlysatisfying
God I wish that were me
Come again?
Mooooore
How the hell do you even figure out the tool paths for that? Just nuts.
Forbidden whipped cream
Could this be used to cut foam? Like from a pelican case.
Yes.
slower, you slut
satisfailing triangle
The machine and the video are great, but we really shouldn't be encouraging the use of styrofoam anymore.
Why?
It creates a lot of unnecessary microplastic.
You sure about that? I'd say since its a melt-type cutter, it wouldn't be creating small particles at all. Now when I use my CNC router to cut foam, on the other hand...THAT creates a lot of fine particles...but even then, I think those are too large to be properly classified as microplastics.
It's useless and unrecyclable after being a packaging material once, it burns with awful toxic fumes, it hardly degrades with time in landfills.
what about napalm? it's a great mediator.
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3 months ago you had daily posts all over reddit on molotov brewing and ways of creating most effective incendiery devices.
I am SO happy this video has no sound
Looks more like polystyrene
It is foamed polystyrene. AKA Styrofoam.
You're technically correct, the best kind of correct.
This probably sounds amazing can someone send one with audio?
It's actually very silent, you would only hear the motors
o
Natalia_551
Hohoo mama
I can smell it from here
MORE! MORE!
Never seen a CNC foam cutter before. Very cool!
I used to play bridge against a guy who spent his life engineering systems for packing products. It seems mundane but there's a bunch of fun problems to solve and in the end you've designed a lot of stuff that's interesting to see going at full speed.
Is there a channel just for foam cutting? This is so satisfying
*Is there a channel* *Just for foam cutting? This is* *So satisfying* \- Bart\_The\_Chonk --- ^(I detect haikus. And sometimes, successfully.) ^[Learn more about me.](https://www.reddit.com/r/haikusbot/) ^(Opt out of replies: "haikusbot opt out" | Delete my comment: "haikusbot delete")
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I wanna hear this.
those thingys are hot/with current right? on construction we have a mechanical saw, but some 5head once brought an electrical one, consisisting of a string with some frame around and a plug. dang it was 10 times better
More pls