Positively fantastic! I adore your way of working and showing your odds job, no music, no comment. All things seems so simple and you made us want to do like you! Nice!
It is so pleasant to see you using the right tools, and you are so good at it ! So many make noisy, sloppy tutorials... Thanks to you, This is brilliant !
+Modepourlol Thank you for your kind comment. I am glad you enjoyed the video. I have also posted a video on a hand held foam cutter that you may like, link in the description notes. All the best. SF
I found the presentation very informative and very clear. Yes, you use some advanced cutting and drilling equipment but that only makes the video time efficient and doesn't preclude the use of hand-tools. I am quite impressed with the end result.
I liked this video, this is the type of DIY video i prefer, no talking just building, and if there are any complicated bits then let text speak for its self.
Very nicely demonstrated. Clear, concise and to the point. Don't be dissuaded by the negative comments. Let them figure something else out on their own. Regardless of how hard you try, some loser is always going to find a way to run down another man's efforts. Keep up the good work!!
Great quality video! It's not about the woodworking tools, it's the great idea and simplicity of design. Keep it up! I would suggest nichrome resistance wire if one can find it. Wouldn't require the resistors. Nice cutter any way you slice it.
Great Video and awesome setup! I only found one issue with this, and I am only trying to help you and others out. When you added the resisters it did not do anything but waste electricity. While you added more resistance to the circuit it was added in the wrong place. The point of the resistance is being in the wire it is what heats the wire up. If you add resistance in another section it will heat up that part aka the added resistors. So they serve no point in the build besides wasting power. Besides that great video!
I have to cut some 4 inch thick 30h high density foam strips about 4 inch wide of a 2ft x 2ft squ section to glue onto the other square peices as the new ones are just a bit small so building this cutter will help in doing the job instead of buying one for a one of job. The foam cost me an arm and a leg as I'm doing my 2 x 2 seater sofa's as the foam cushions you sit on is way too soft as you sink into it. Many thanks for the idea
I really enjoyed your video! I am the kind of person who likes to build a tool or something for a purpose I have & see it work the way it was intended, instead of shelling out hard earned $. I have a need for one of these & yours fits that need thanks & thumbs up & I subscribed
Here are some useable specifications using nichrome wire and a 12 volt car battery. To get 36 watts of power, use exactly 18 inches of 26 gauge type 80 nichrome wire. If it isn't hot enough, shortening the wire to 15 inches will give you 43 watts. Shortening it to 12 inches will give you 54 watts. If you find 36 watts is too hot, lengthening the wire to 21 inches will give you 31 watts, a little down from the 36 watts. You might want to experiment with the length before you make the final size of the frame length spacing. If you have made the frame too big (meaning you need the wire to be shorter), just add 16 gauge copper wire to make up the difference. The copper won't heat up. Don't use anything but a car battery or a good motorcycle-size 12 volt battery with good connections, using 16 gauge or larger insulated copper conductors. If you have a 12 volt power supply which will put out at least 5 amps, you can use that instead of batteries. Attach the copper conductors to each end of your nichrome wire with a secure mechanical connection. You cannot solder copper to nichrome wire (the solder may melt even if you could). Using one of the above recipes will waste almost no power anywhere but in the nichrome wire. The highest current will be about 4 amps, for the lowest wattage about 2.6 amps. Not much for a car battery. Watch out and don't burn yourself. You are, after all, heating a wire hot enough to melt plastic pretty fast. You should know that I have never built a styrofoam cutter. I just know how to do the math for wattages etc., so I don't really know how many watts it takes. I assumed from the video that something around 35 watts works because according to the instructions there he was using about that much. The other 70 watts or so were just heating up the resistors.
+Damian Appert Thanks for the great info, However there are certain aspects in practice that mean you need a little more power than in theory. The main one being power loss through heat dissipation. This can even be affected by the temperature of the room you are using it in, If your workshop is 10°C the cutter will need a higher wattage than if you are in a heated workshop as the wire looses heat quite rapidly. Too Hot and the polystyrene melts too much, too little and it won't cut cleanly. A simple way is to use a light dimmer on the transformer (or a basic Pulse width Modulator, although a dimmer is the easiest to source) that way you can adjust the power to the task you have in hand. all the best SF
+Swallow Forge , good comment. I think I would suggest a variable 30 volt power supply with a capability of at least 3 amps if someone is willing to go for the extra expense. Another easier way might be to stay with one of the recipes I suggested with the 12 volt battery, then just add a little extra resistance wire length for cooler operation and then use a copper shorting clip wire to short out some of the resistance wire to get a higher wattage on what remains. The resistance wire then becomes a variable resistor as more or less of it is shorted out. To be clear, the shorted part would remain cool and the rest would get hotter, so attach one end of the shorting wire to the top and the other end just part-way down the resistance wire. This last suggestion may be a little more palatable to those on a tighter budget. I would caution folks to be careful not to accidentally short the entire resistance wire because this would produce some very dangerous heat and sparks. The shorting wire would melt in your hands!
Thanks for the video and the electrical specs. I've thought about making one for awhile because saws and knives make such a mess. Now I have the info I need thanks again.
Thanx for this cool DIY video! I have some quaestions. You want to use 100W power to cut. And you use serial connection with 3 resistor and an other resistor as a steel wire. Thats a voltage divider. Steel wire become 24V*(1,5 Ohm/6 Ohm) =24*(0,25)=6V. This Wire also have only 6V. This 6V with 4,1A current make cca. 25W to heat. Also the other 75W is to loose on the 3 sistors. Have i may a mistake, or thats is good theory with this 25W heating. (Sorry for my English. I only learned with datasheet readings.) I wait for answers.Thx
That’s exactly right. The power supply does indeed provide around 100 watts of power, but most of that is warming the 3 resistors under the platform. However, it appears that 24 watts is enough to cut the styrofoam (power through wire I squared x R, 4 A squared=16 x 1,5 ohms=24 watts).
@@philipbowman6415 Thx for your answer Philip Bowman . My project is immediately done. I prepared out a resistor wire out of a bad hair dryer with 5 Ohm resistant/m. I had hav'nt other used resistors too. It works fine, but the heat can be faster the resistor wire to burnout. Thank for your fine answer ;). And good day for you!
You could use kanthal A1 for wire. Its durable and I use it for vaping. I just finished my small foam cutter and used kanthal A1 0.35mm/27AWG 14,95ohm per meter. You might not need those resistors anymore. My foam cutter's total resistance is 1,85ohm and I used one of my batteries for vaping- sony 18650 Li-ion 3.7V 35A. It goes to 2.2~2.4A.
Great idea. I should point out that the actual power at the heating/cutting wire is about 24W, the rest being dissipated by the 3 resistors. Would it not be better to power this from the 5volt output of a cheap computer power supply? These can provide about 20 Amps @ 5v or even 30Amps at 3v
Superb woodworking. The electrical principles though… well… When I make one I’ll use this MDF plan, it’s superb. But I’ll constantan wire for higher resistance and a smaller, cheaper power supply. I won’t rely on a cold resistance measurement. Instead I’ll measure current and voltage when operating and calculate resistance. What you have there is something like a 12W wire cutter with a 40W heater underneath.
There is an additional variable power supply video on the channel. You are quite right about the heat dump, and but the idea was to make it super simple requiring no electronics. Check out the power supply video using a simple pwm to give better temperature control using nichrome wire.
Nice Job, You can buy a "Doorbell" transformer at Home Depot. I believe they come in different voltages, 16 or 24 volts.. You can run it with a regular, wall Dimmer switch, instead of using resistors.. That way, You can adjust the heat for thicker Foam.. If you're gonna use the blue foam, It's a little denser and needs a little more heat to cut too. I'm not criticizing, just adding suggestion for the viewers that don't have any parts on hand and have to build from scratch..
Don't use a guitar string, use a piece of constantan wire. You can get constantan in a 0,2mm thickness and 16,1 ohm per meter, ½ meter = 8,05 ohm and so on. with the constantan wire you can get the same result with ~25-50W
You should sell the pieces as a kit on ebay! Most of us don't have access to all the machines to cut all this out. Would make for a great shop class project thou!
I saw another video where a the wire was attached to the top with a spring and hook so you can quickly disconnect the wire for "inside cuts", though I suppose thats not a problem for you.
I couldn't tell you the difference between ohms law and teslas. But I was wondering why did you pick 100 as your choice? I've always been fascinated with the way people make the indentations in my pistol boxes so smooth and the pistol sits in so perfectly. I've tried with razors and bandsaws but this looks like it would do exactly what I'm looking for. I could come in on the side and profile my weapons and glue the entrance and it'd be perfect. Thanks for sharing since you did all the electronic math, I wish I'd stayed in electronics class back in the 70s.
If you use resistor, your powers on nihrom was only 24wats, because voltage on resistors 4.5 om was 18volts, however it means with 4A in circuit = 72 wats on resistor???
I would have used a switching power supply this way you can regulate the voltage (which can be handy with thicker or thinner material cutting) awesome design tho!
Nice video, thanks for sharing. A suggestion if it's okay - all your video is silent. Great. Please silence the sound of the saw cutting the wood. Not nit-picking, the video is clear and useful. Thanks also for giving your starting point of 100W. As kids we used to put a needle instead of the soldering iron bit in a high wattage / electrical soldering iron to cut (what we call) Thermacol. I was too young to note wattage (!!) We used to / tried to do intricate designs for festival decorations. But there the success of circles, flowers, even straight lines(!), let alone intricate designs etc are dependent on the individual's skill. Liked the video. Thanks,
Well first I need to build my own miter saw, band saw, radial sander, drill press, multimeter, and soldering iron. So if you could just upload those videos next that'd be greeeeeeat. Cool video!
You dont need to build any of those things. You can use a hand saw and a drill and a screwdriver. I already have the tools so I use them as its quicker. if you dont have a soldering iron use connector blocks. There are always ways around any problem, just look around at what you have and find a way of doing it.
Doesn't shunt simply heats the air with no use? The string dissolves only 25 Watts of power, and 75W of designed 100 are dissolved on shunts. Seems the same efficiency for foam cutting could be reached using some 8 volts transformer.
As pointed out in other comments you waste much energy in the resistors (~70W). To avoid this and to improve the hot wire cutter you could use a mosfet (n-mosfet) which you can regulate with a potentiometer. It's not complicated and will also allow you to control the heat.
+martin richardt Needed Parts are 2*diode, Mosfet IRFZ44N, capacitor (>=35V, >=220uF), 2 resistors (4K7, 1k2) and a potentiometer (50K). The parts are not expensive and cost alltogether only a few bucks. If you interested I can provide the schematic, which I checked it with LTspice.
+martin richardt I'll appreciate if you could give me the circuit diagram with the potentiometer, because I have never worked with it. This is my mail: misionpage@gmail.com Greetings from Spain!
Swallow Forge Im glad i searched this video up. Im now a subscriber due to the fact I saw cool projects as i finished watching this one. In the feature I hope this channel is still good! :D
BEAUTIFUL!!!! So great!! But I am another person that does not know electronics and all my radio shacks are gone. Can you make a shopping list of what to look for? And did you incorporate a ON/OFF switch anywhere?
hey, in the plans for the cutter, does it say what to buy/ the total cost of all the items? i am trying to see if it is worth it for the cost of the materials and the effort to make it. Thanks so much for this great tutorial
+Ton Loef I would have to politely disagree with you there. Because nichrome wire has a stable current to temperature ratio it is much easier to control the current.
i like it, and i know it will help me in my projects. could you please list down the materials that will be needing for this DIY styro cutter? thank you.
Nice video. Thanks for sharing. How much does it cost in money for the materials to make one? MDF (wood/plywood or whatever) I have, so in fact it's only the wiring the power supply, the resistances and the cutting wire?
Ha ha yes thats very true. along with the updated saying "Those that can... do, Those that can't .... tell everyone how they could have done it better if they had those tools..." :) Thank you forr your comment, cheered me up no end :)
There's a lot of people that aren't too bright out there. You should really use something to push/pull the wood through the blades. On second thought, natural selection.
Have you ever heard of kanthal or nicrhome? You should use those as Heating wires and the thinner you make them the more precised your cut will be and the more resistive it will be. Then you wont need those expensive and wasteful resistors.
You will still need to regulate the power supply regardless what you use as the wire. Otherwise you will simply end up with a puddle of rapidly cooling metal.
Nice work.Great vid!I'm going to build this one for making model train structures.If it helps you can buy the wire at most model train supply shops.Thanks.
Hi. I have a question. I'm using Nichrome wire 0.40mm a length of 20 cm. I use a power supply of 9 volts and 1 ampere, but noted that not hot enough to cut well. You can suggest me which is the necessary power? Thank you very much for your answer. Greetings from Argentina
Yeah I should have just taken the transformer apart and removed some of the windings instead. If only I hadn't wasted six years studying electronics. Oh the humanity.
Swallow Forge Or do something as simple placing a PWM current controller between the output and the wire or maybe even an off the shelf dimmer at the input. Also there are a lot of off the shelf switching supplies that you can easily adjust to the voltage you need. I'm not belittling the effort you've put into the design, it looks neat, but cooking that much excess power I'm not a fan of. I'm thinking of doing an NC version
You all make valid points, and i was previously aware of all of them, however this is a super simple project with very basic maths and components. I do have and use nichrome wire, however again in this project i wanted to keep it simple. same with the power supply, despite its inherent inefficiencies, it uses parts the most people could find without having to pay out any money. for example I have a very expensive regulated dual power supply i could have just plugged it into, but then people would complain that nobody can spend £400 on a power supply.However, I plan on doing another video on a bow cutter, I will endeavour to give more options on that one. These things aside, I do hope you enjoy my videos, I genuinely only make them to try and help people have a go at something they thought was beyond their capabilities.
+Swallow Forge I need to make this project myself and havent done it before so I appreciate your video and effort. I have to cut stronger materials though. But Id like to know why you didnt create a plug and into the wall instead of using a specialized power supply? If straight into the wall mains would result in too much voltage to a high gauge (thin) wire, isnt that then the purpose of a dimmer switch?
Don't sweat the nay-sayers, I thought this video was great and I've watched a bunch of them lately. I like your spring design best (over the other videos) and will be incorporating that into my design. Still gathering parts but I will soon have one of my own 😎 Also mine will be mainly for plastics so I'm having to "beef it up" a little.
excellent project - well done (liked&subscribed)...............love the "bloody great trisquare" 'tis my favorite measuring device also.......................JRW
Would this work with a power supply that outputs 4.75V and 0.55 Ampère, which would mean a resistance of 8.64 ohms. If i had the same cutting wire as yours then I would have to add a resistor of about 7 ohms. Would this work or did i forget something? Thank you in advance.
I am making one, but can't get the circuit to work... I was using nicrom wire stripped from a hairdryer and a 12 volts transformer, coud you please give me any direction on this? is the voltage too low? what shouild i do? I do have access to a pc power source... could it do the trick?
+amaral sanchez it may be that the power supply you are using cannot provide enough current for the length of wire you have. A bigger transformer may help. If you can, measure the resistance across the wire. And use the power triangle to calculate how many amps you require. I found about 100watts gave enough heat to give a nice clean cut. But you may have to experiment.
I worked on a sign shop cutting styrofoam letters with a similar hot wire table. It was set up with a regular light dimmer switch like my mom had in her living room. This was connected to a 24 volt transformer you see in home central air conditioning systems.
Make a jig that slides along the table. That you can adjust for size/ angles. So you can make consistant 120degree cuts. If you look at table saw jigs it will give you some idea of how to do it. If you are really struggling, contact me at facebook.com/swallowforge and I'll see what i can do to help. :)
Would you please tell me that how can I make Styrofoam ball (like cricket ball) of different sizes using Styrofoam cutter? Would you please make a tutorial on it?
Nazrul Islam idiot ..are you using your mind? you cant make a perfect ball from foam unless you have a very good machine from the best manufacturers..do you think that improvise device can make it? its a big NO..thats why this uploader didnt reply to you because even him unable to do that without a help of perfect machine.
put up a link to buy the power source online. the power source is alot more complicated to figure out then how to connect two ends of a wire. people aren't going to know what amp/watt rating to buy for a 24 v transformer
Hey, I really want to make this but I don't have access to the power tools. Do you have a recommendation on what to do or if you have a premade one that you recommend?
+TheOnlyLite You can make all of this with a hand saw or cheap Jigsaw and a drill and a screwdriver. You don't need all the tools, it just makes it faster. Theres Downloadable plans on my website www.swallowforge.co.uk Hope that helps, SF if you require any help/ questions feel free to contact me via my facebook page facebook.com/theswallowforge and I will do my best to help.
