one problem you should keep in mind: what you made is an inductor. wire wound resistors are wound with coils opposing each other connected in parallel to the leads. This is what cancels out the inductance. So, if the resistor happens to be located tightly enough to be within magnetic field range, it does not induce a current in the other part. The one you made would need to be installed sufficiently far to be magnetically isolated
i suspected this problem already which is why i started to look up tutorials for wire wound resistors on youtube in the first place. thanks for confirming my suspicion and offering a solution!
@@hernancoronel because inductor effects usually come in at high frequencies, and if they aren't for audio applications they should be fine. Alternatively, they are using ayrton-perry windings, which reduce capacitance and inductance. Though you will need some thin substrate to make them.
@@tarstarkusz Ya, they charged my brother 15$ for an 18650 battery cell XD. I held up my ~1$ cell and said you mean one of these? He goes ya, but I want to get the one they recommend. I tried explaining that this was a standard part akin to a AA battery but he wouldn't listen. *face palm*. Point taken though Michael the question being begged is if you installed this coil without all the fluff to where it couldn't move, you could make a resistor...but it would get red hot like a toaster and catch fire because there is no heat dissipation. However, in some applications where you are just quickly draining current? Why not! Otherwise though, the key is to think of a way to cheaply encase it. If you have plaster on hand, then that part is "free" anyway. I also have just bare tinned copper wire which is way cheaper than insulated wire. This is ~7$ for 100 feet from my supplier. Perfect for jobs like this.
@@peterlamont647 Worse than that, the re-wraps the ecig vendors sell are junk that are not rated for the kind of current a good coil draws. In the old days, the coils were always more than an ohm and the current draw was fairly low. Now a days a good ecig starts at 40 watts out of a single cell.
@@peterlamont647 there's are big differences when it comes to high current batteries. They are definitely not standard. If you can get them for a dollar, that's much cheaper than I've ever seen them. A quality li-ion battery usually costs 7-11 dollars.
Question: I have a lot of thin gauge heatshrink tube. I need to make a few 8 ohm resistors. Could I slide the shrinktube over the nichrome wire and wrap it around a plastic tube, like an old BIC pen, or a wooden dowel cut to length -- and drill a 1/16" hole in each end and feed the lead through that? Secure with super glue or epoxy at the ends if necessary. It might dissipate the heat better. Any thoughts on that?
Waw very nice video, thank you very much I have a question can i replace 5w cement resistor 3.9ohm to 4.7o ohm?that will not be couse any damages to PCB board?
Good idea. Just a caution to new diy-ers, don't use beach sand for this project. The salt content ends makes it more conductive and hence less resistive. Possibility of leakage/short too.
@@johnf3326 LOLLLLLLL ya. That's a great point. Just calculate the length of copper wire to get that resistance. I think its like 30ohms per meter? Don't quote me. Look it up any future readers.
@@johnf3326 Ya, hence that caveat emptor I added. I really don't know other than the principal itself, that copper wire does have resistance based on it's diameter and length. Where I read that was in an application with very thin wire indeed. It was a circuit board trace.
GREAT VIDEO!! Is there a way to find the maximum amount of current that can be put through a certain gauge of nichrome wire in air at room temperature? BTW: Your giant induction heater videos were AWSOME!!
I disagree. Yeah, 5 watts is 5 watts, but one is 5 or 6 TIMES the size of the other. It has more heat capacity and more surface area to radiate said heat. Also, shouldn't you also make it black? Black objects can radiate more heat. Also, couldn't you increase the surface area by instead of using masking tape for the bottom, you used a small heat sink (to mold the shape of the heat sink into the end resistor) though I don't think plaster is the ideal material for such a shape as the fins would want to break off? How are they able to dissipate so much more heat in such a smaller package?
First I totally enjoyed watching your video. I wonder if you can make higher waltage. I am going to make a one ohm resistor for cro to measure current. The commercial resistor has at least 5% error. It is good to make one with high waltage and high accuracy myself. The heat dissipation however will be a problem for high current.
I'm interested in its commercial aspect. What sort of machines, raw materials and equipments are required to setup a production unit? Do you have some references?
Nice informative video, thank you. Have you thought of filling a plastic soda straw with your plaster and sand mixture? Then use the resulting rod as a form to wind the wire around. Doing that would almost guarantee controllable spacing between turns. You would still pot it after to finish it.
Yes I have thought about that, However the mixture I used in the video would be to fragile, it would break before you got a single turn on it. Better off buying a ceramic rod from eBay or alike, and use that as a winding core
Nice procedure, but the resistor is useless in high frequency applications (over 10MHz), since it acts as an inductor. Better way is to build with the wire some kind of zig zags, not loops. For example, in an FM transmitter's main resistance over the lamp's anode, your resistance will act as a high frequency isolator.
Do you need to somehow control how much current runs to it? Im wondering if attaching it directly to a cell to bleed the cell a bit is dangerous. If said cell can dish out a kilo amp, wouldn't this resistor fail instantly?
Couldn't you make this thing much smaller, maybe even smaller than the commercial one, if you used an insulated ni-chrome wire? Do they make it with the same kind of insulation that speaker wire has?
If you wound TWO layers in opposing directions (insulated from each other), then the inductance would cancel due to the close che close coupling. This is called "inductorless" wirewound resistors....I have seen some for sale at one time...rather hard to find? I actually need many strange-valued power resistances
I'm sure there must be something out there to improve thermal transfer. Tricky one though, has to be cheap, non conductive, and relatively high temp resistance.
Schematix yes, I keep thinking about the power resistors that have an aluminium heatsink around them, don't know if they are wire wound. Be interesting to know what they pot those with. Not sure if I have any to have a dig at.
There are thermally conductive epoxy compounds that are used for potting the resistors you mentioned, as well as things like relay coils and motor windings. They're not as conductive as metals, but they do a nice job of evenly distributing heat and carrying it a short distance to a heat sink.
+Jim Watts Yes those you are referring to are indeed wirewound, im not entirely sure of their composition inside, but needless to say its poured in the casing with some heat conductive compound. You used to be able to get ceramic tube years ago for winding your own, but i see its available on the likes of ebay, you would need to use some sort of diamond cutter to cut the lengths down on a lathe though.
So there's no formula for the watt, I though that the watt could be measure from how much coil made. But in this video makes me know that the watt are estimated by the big of the cement block
According to the engineering toolbox a plaster/sand mix has a thermal conductivity of 0.7W/mK while epoxy has a conductivity 0.3W/mK, while cement/morter is 1.7W/mK. www.engineeringtoolbox.com/thermal-conductivity-d_429.html Given that sand is mostly SiO2 which is quartz which has a thermal conductivity of 3.0, a packed sand and epoxy binder could produce an acceptable fill material (90% sand?), though the cement looks good and it's a question of crack resistance from thermal expansion and contraction. The plaster/sand mix may be the better choice in that regard and the mix viscosity will have an effect on density and final thermal conductivity. With epoxy I'd be concerned about the temps it'd be put under and 120°C+ could be a big issue. It'd require a special epoxy compound and not your typical two part stuff. All coils form an inductor, though without the ferrite or iron core the effective inductance is fairly small, though not completely insignificant depending on the application.
Maybe if you used a spacer (for example, a wire with the thickness you want the distance between the turns to be), it would make your life easier, making the resistor come out with the correct spacing.
Probaly more Daleee like dude...Rougherrr rockierrr composistion...the ones pulled out and or went bad floated when hottt...was them softerrr onesss.....id highly recommend it dude...maybe it handles the heat well man.
The wire doesn't matter in the slightest. You could also use kanthal. Just worry about the resistance. The same amount of heat will need to be dissipated regardless.
4mins 5secs in. Solder to Nichrome? How? Solder won't attach to nichrome, thats partly why attachments of wire (copper) to nichrome are done with preasure fit crimps.
igrewold depends on what kind of course compound, some gray stuff uses a different kind of ceramic if memory serves, and if it's isolated using epoxy then you shouldn't have any issues.
Not a bad idea. It's hard for me to buy custom let alone high watt rated resistors. I wonder if I was to shove one of these into a aluminum conduit tube would it increase the power rating.
I expect it would, as "FlingShotsman" said there are thermally conductive epoxy compounds used for potting wire wound resistors. Combining that with alloy tube should make a decent improvement for thermal temps. eBay or Mouser or RS (not radio shack) all sell high watt wire wound resistors and ship global. Even the ones off eBay for a few dollars have performed well for my uses.
Yea I hate ebay, had to many mishaps let along takes a month for it to arrive since 90 percent of the time it comes from China. All the local places want too much for shipping and have to spend a lot for it to be worth the shipping.
For some people; electrical circuitry is an art form that they take pride in, I one day hope, to be able to make any kind of circuit from virtually anything... I could make my own transistors. And I mean in a snap situation.
Another reason is you usually can only buy them online now. So you pay 1 dollar for the resistor and 10 dollars for shipping and handling. Thats why I'm here.
Nice tutorial! I guess however that both resistors will act somehow like an inductor. Is that true, and if yes,do you need to compensate that behaviour?
Because the coil does not have a iron or ferrite core the inductance would be next to nothing. It would be fun to test though. Perhaps you've given me an idea for a future video :)
Yes, wire wound resistors do exhibit some inductance and can't be used in places where that will have a detrimental effect on circuit behavior. Characterizing a few of them would indeed make an interesting video!
+FlyingShotsman Yes , your right and even carbon film or metal film resistors have inductance, albeit much lower. Thats why my tube amp im building deliberately makes use of wirewounds to act as an extra filter choke. The only non inductive resistors are carbon composite, and these are extensively used in RF circuits where low inductance is critical to their operation.
Great video! !!! sir I have a question for you I'm wondering if your interested in building me a heating element. .. To simplify things I'm looking to reach a temperature of 36c of roughly 5oz water however it must be battery operated with 9v batteries or less . I've seen similar set ups on you tube but I would like it professionally done that's why I'm reaching out to you . please get back to me thank you.
I had a crazy idea a while back of making a "revolver" regulating circuit. Based on the physical principal of V/t in switching supplies where they average out the voltage by cycling off states. Only in this case, you cycle components instead. If you "revolved" which resistor was being used at any given time, you almost definitely could get away with cheaper smaller parts. I was thinking of applying it in voltage regulators which have a 1 amp rating. If you revolved 10 of them you could probably cycle 10 amps briefly through each one for one second. Then hopefully after 10 seconds, 1 second for each component, you could then burst 10 amps through for another second and fire off each one down the line. Would be very cool if it worked!
hi.. if i have 10ohm 100w and i need upgrade to 400w for my project. can i use same resistor and make new ceramic cover? any calculation for ceramic cover size?
Man, that is a great question. Since no one answered it, my advice would be to put thermal compound on top and plop a big ol' aluminum heat sink on there with a fan. It works for power supplies up to 1000 watts, so why not in your application? Just uh...test it outside for a few days in case it catches fire. ;) PS Use metal universal clamps to mount the heatsink tight.
I was actually surprised with the power rating. I was expecting the diy would be higher/much higher then 5W since there is a lot more mass to dissipate all that heating.
well they all kinda were years ago...roughhhh like that...that's newerrr and china playing with cement and idk a more even porous smoother composition...no it don't really matterrr you'll still get years out of it so it is what it is etc lol.
cement and is wirewound...smoked that one that one in the b52 sorta cathode bias, but not exactly.. cathode return shit but more volatile etc lol....one in it just old..lol...have an excellenttt replacement Vishay/Dale like Yageo thing lol.
5 watts is 5 watts. I tried to explain that to a guy that was trying to hard-sell me a more expensive electric space heater. He tried to tell me that it was more efficient, lol. After we argued for a bit I couldn't help but ask him if he was being paid commission; he swore he wasn't. I was irritated that he thought he'd dupe me, but, thinking back, he might have actually believed what he was telling me.
Yes there are plenty of scams out there. Knowing even the basics about electricity has saved me and I'm sure other people. No matter how you cut the cake, 5 watts is 5 watts like you said. :)
Well its not the same thing. A space heaters efficiency is based on how quickly the unit can heat the room to the desired temp. So if you have two 100 watt radiators, they will heat up to the same temperature, but if one has greater surface area, it would heat the room up a bit faster and therefore be more efficient because you wouldn't need to run it as long.
Even if the surface area is smaller, where does the energy go? The unit with less surface area heats up to a higher temp, but all of that heat energy winds up in the room eventually. The kilowatt*hour of heat energy into the room is the same regardless of the electric heater chosen.
If it heats up a room faster, then it's drawing more current and using more energy while it does it. The cost is the same. It's not more energy efficient.
TediCreations this is how all wire wound resistors are made. Yes there will be some induction in the resistor, however it acts as a resistor for most corcuits because the coil is so small without a core. The company I work for makes resistors and I've seen this process plenty of times. If you need proof just watch one of the countless videos showing what's inside a higher wattage resistor, you'll find many made from potted ceramic or epoxied into an aluminum extrusion the second of which is what my company makes mostly.
@@InventTwig not all of them, many if not most are just a single coil wound within a ceramic case encapsulated within the resin core of an aluminum heat exchanger. I worked on every step of this process besides the resin molding for over 2 years before our management changed hands are everything went to $#!t.
one problem you should keep in mind: what you made is an inductor. wire wound resistors are wound with coils opposing each other connected in parallel to the leads. This is what cancels out the inductance. So, if the resistor happens to be located tightly enough to be within magnetic field range, it does not induce a current in the other part. The one you made would need to be installed sufficiently far to be magnetically isolated
I have seen lots of vintage resistors which seem to be wound exactly like the video shows and they are still working well even today. How come?
i suspected this problem already which is why i started to look up tutorials for wire wound resistors on youtube in the first place. thanks for confirming my suspicion and offering a solution!
@@hernancoronel because inductor effects usually come in at high frequencies, and if they aren't for audio applications they should be fine.
Alternatively, they are using ayrton-perry windings, which reduce capacitance and inductance. Though you will need some thin substrate to make them.
@@hernancoronelIt's fine-ish for dc. But for ac it's horrible
Very good, you got to the point and added all needed information, very professional and educational.
Appreciate the derailed instructions & test results. These are usually missing in DIY.
Excellent in all aspects. Many thanks indeed. You have earned my subscription. 👍🇬🇧😷
Wait, is the nichrome wire the actual resistor and the ceramic just a heat sync for it?
Yes. The ceramic is the potting compound and heat sink. The nichrome wire is the resistor. You could also use kanthal.
Just stay away from e-cigarette vendors because they jack the prices way up.
@@tarstarkusz Ya, they charged my brother 15$ for an 18650 battery cell XD. I held up my ~1$ cell and said you mean one of these? He goes ya, but I want to get the one they recommend. I tried explaining that this was a standard part akin to a AA battery but he wouldn't listen. *face palm*.
Point taken though Michael the question being begged is if you installed this coil without all the fluff to where it couldn't move, you could make a resistor...but it would get red hot like a toaster and catch fire because there is no heat dissipation. However, in some applications where you are just quickly draining current? Why not! Otherwise though, the key is to think of a way to cheaply encase it. If you have plaster on hand, then that part is "free" anyway. I also have just bare tinned copper wire which is way cheaper than insulated wire. This is ~7$ for 100 feet from my supplier. Perfect for jobs like this.
@@peterlamont647 Worse than that, the re-wraps the ecig vendors sell are junk that are not rated for the kind of current a good coil draws. In the old days, the coils were always more than an ohm and the current draw was fairly low. Now a days a good ecig starts at 40 watts out of a single cell.
@@peterlamont647 there's are big differences when it comes to high current batteries. They are definitely not standard. If you can get them for a dollar, that's much cheaper than I've ever seen them. A quality li-ion battery usually costs 7-11 dollars.
Question: I have a lot of thin gauge heatshrink tube. I need to make a few 8 ohm resistors. Could I slide the shrinktube over the nichrome wire and wrap it around a plastic tube, like an old BIC pen, or a wooden dowel cut to length -- and drill a 1/16" hole in each end and feed the lead through that? Secure with super glue or epoxy at the ends if necessary. It might dissipate the heat better. Any thoughts on that?
Waw very nice video, thank you very much
I have a question can i replace 5w cement resistor 3.9ohm to 4.7o ohm?that will not be couse any damages to PCB board?
i used aquarium sand, it's grain is more fine than play sand
Good idea. Just a caution to new diy-ers, don't use beach sand for this project. The salt content ends makes it more conductive and hence less resistive. Possibility of leakage/short too.
very nice information video...i was searching it but not found...hope you will make one for braking resistor type high watt 500 watt 50 ohms.
Thank you i need to make a 5w 0.012ohm wire wound resistor for my ham radio. Now i can thank you.
Isnt that called a piece of wire?? 😂
@@johnf3326 LOLLLLLLL ya. That's a great point. Just calculate the length of copper wire to get that resistance. I think its like 30ohms per meter? Don't quote me. Look it up any future readers.
@@peterlamont647 at 30 ohms per metre thats gotta be very thin copper wire!
@@johnf3326 Ya, hence that caveat emptor I added. I really don't know other than the principal itself, that copper wire does have resistance based on it's diameter and length. Where I read that was in an application with very thin wire indeed. It was a circuit board trace.
Just out of curiosity, is the no any inductance due to the wingdings?
why not use lacquered nichrome wire? if you can get it....
If you need to Jerry Rig something let JR know man...still wellllll skilled at this dude lol.
GREAT VIDEO!!
Is there a way to find the maximum amount of current that can be put through a certain gauge of nichrome wire in air at room temperature?
BTW: Your giant induction heater videos were AWSOME!!
I disagree. Yeah, 5 watts is 5 watts, but one is 5 or 6 TIMES the size of the other. It has more heat capacity and more surface area to radiate said heat.
Also, shouldn't you also make it black? Black objects can radiate more heat.
Also, couldn't you increase the surface area by instead of using masking tape for the bottom, you used a small heat sink (to mold the shape of the heat sink into the end resistor) though I don't think plaster is the ideal material for such a shape as the fins would want to break off?
How are they able to dissipate so much more heat in such a smaller package?
First I totally enjoyed watching your video. I wonder if you can make higher waltage. I am going to make a one ohm resistor for cro to measure current. The commercial resistor has at least 5% error. It is good to make one with high waltage and high accuracy myself. The heat dissipation however will be a problem for high current.
Run the winding in open air? Maybe a fan to blow across it?
I'm interested in its commercial aspect. What sort of machines, raw materials and equipments are required to setup a production unit? Do you have some references?
Nice informative video, thank you. Have you thought of filling a plastic soda straw with your plaster and sand mixture? Then use the resulting rod as a form to wind the wire around. Doing that would almost guarantee controllable spacing between turns. You would still pot it after to finish it.
Yes I have thought about that, However the mixture I used in the video would be to fragile, it would break before you got a single turn on it. Better off buying a ceramic rod from eBay or alike, and use that as a winding core
I suggest use a long bolt.
@@manla8397 a bolt would be conductive...
LIKE GOES FROM BAHIA BLANCA, ARGENTINA
Nice procedure, but the resistor is useless in high frequency applications (over 10MHz), since it acts as an inductor. Better way is to build with the wire some kind of zig zags, not loops. For example, in an FM transmitter's main resistance over the lamp's anode, your resistance will act as a high frequency isolator.
yeah, but a better way would be to fold the wire in half and then wrap it
Great video, thanks. I too test my power resistors with a thermal gun.
Good video, but I can't get solder to stick to the nichrome wire...
So where do you get nichrome wire? Hardware store dont sell it.
Do you need to somehow control how much current runs to it? Im wondering if attaching it directly to a cell to bleed the cell a bit is dangerous. If said cell can dish out a kilo amp, wouldn't this resistor fail instantly?
Yes it would fail no doubt
Couldn't you make this thing much smaller, maybe even smaller than the commercial one, if you used an insulated ni-chrome wire? Do they make it with the same kind of insulation that speaker wire has?
Also you should measure the resistance at 5w load at high temperature to see if it holds the same resistance
If you wound TWO layers in opposing directions (insulated from each other), then the inductance would cancel due to the close che close coupling. This is called "inductorless" wirewound resistors....I have seen some for sale at one time...rather hard to find?
I actually need many strange-valued power resistances
Can you tell me the significance of using sand and plaster of Paris? Or would an epoxy such as j.b. weld suffice?
JB Weld is a plastic material....won't work. Plaster and sand mix is best (as shown).
👍
Well done, thanks 👍👍👍
What does adding the sand do?
Sir , Where to connect plus and minus wire of dc in ceramic resistor as a heating element .....
Very hand & informative 👌👍👍
bro how to establish in a commercial way, what is the machinery set up kindly guide me
Great video, the little plastic form works great.
I wonder what other material you could use for encasing the wire with better thermal conductivity.
I'm sure there must be something out there to improve thermal transfer. Tricky one though, has to be cheap, non conductive, and relatively high temp resistance.
Schematix yes, I keep thinking about the power resistors that have an aluminium heatsink around them, don't know if they are wire wound. Be interesting to know what they pot those with. Not sure if I have any to have a dig at.
There are thermally conductive epoxy compounds that are used for potting the resistors you mentioned, as well as things like relay coils and motor windings. They're not as conductive as metals, but they do a nice job of evenly distributing heat and carrying it a short distance to a heat sink.
Ah interesting, thanks for that. Have to do some Googling re the resin.
+Jim Watts Yes those you are referring to are indeed wirewound, im not entirely sure of their composition inside, but needless to say its poured in the casing with some heat conductive compound. You used to be able to get ceramic tube years ago for winding your own, but i see its available on the likes of ebay, you would need to use some sort of diamond cutter to cut the lengths down on a lathe though.
Nice video, thank you!
Thank you :)
So there's no formula for the watt, I though that the watt could be measure from how much coil made. But in this video makes me know that the watt are estimated by the big of the cement block
Very cool video
Great job dear
Excellent tutorial
Excelente trabalho ...
Nicely done,.. not the usual droning on and on, overly technical video.. :)
Could you use epoxy instead of plaster? Also, are these not inductors because there is no ferrite core?
According to the engineering toolbox a plaster/sand mix has a thermal conductivity of 0.7W/mK while epoxy has a conductivity 0.3W/mK, while cement/morter is 1.7W/mK.
www.engineeringtoolbox.com/thermal-conductivity-d_429.html
Given that sand is mostly SiO2 which is quartz which has a thermal conductivity of 3.0, a packed sand and epoxy binder could produce an acceptable fill material (90% sand?), though the cement looks good and it's a question of crack resistance from thermal expansion and contraction. The plaster/sand mix may be the better choice in that regard and the mix viscosity will have an effect on density and final thermal conductivity.
With epoxy I'd be concerned about the temps it'd be put under and 120°C+ could be a big issue. It'd require a special epoxy compound and not your typical two part stuff.
All coils form an inductor, though without the ferrite or iron core the effective inductance is fairly small, though not completely insignificant depending on the application.
Maybe if you used a spacer (for example, a wire with the thickness you want the distance between the turns to be), it would make your life easier, making the resistor come out with the correct spacing.
Easily achieved by winding nichrome and a strand of fibreglass together as a pair.
How about 12 volt and 50 watt resistor to simulate O2 exhaust on a vehicle
50W 12V bulb, could even wire somewhere to be seen, so you know its working.
Probaly more Daleee like dude...Rougherrr rockierrr composistion...the ones pulled out and or went bad floated when hottt...was them softerrr onesss.....id highly recommend it dude...maybe it handles the heat well man.
thank you sir! i love you
I hear you can also use Kanthal or Nickel resistance wire as well. Can anyone confirm this?
you tested the heat but you did not do a resistance test to see how many ohms.
how much voltage we need to the all resisters
I'm thinking with sand being such a good insulator it might be a good idea to use a different material.
Get impure sand with iron dust in it
@@animatrix1851 iron dust should be a conductor.
@@flightisallright only if every iron particle lined up in a row...
This vid made me sub. Thanks
I've got some nichrome 80 wire lying around. Is it terribly different compared to 60?
The wire doesn't matter in the slightest. You could also use kanthal. Just worry about the resistance. The same amount of heat will need to be dissipated regardless.
4mins 5secs in. Solder to Nichrome? How? Solder won't attach to nichrome, thats partly why attachments of wire (copper) to nichrome are done with preasure fit crimps.
Very nice video, would maybe a mix of this silver gray syringe cpu stuff, for better heat transfer, work with plaster of paris?
it will be conductive thus changing resistance amount and then you might even have lotsa capacitance.
try it and see
igrewold depends on what kind of course compound, some gray stuff uses a different kind of ceramic if memory serves, and if it's isolated using epoxy then you shouldn't have any issues.
Not a bad idea. It's hard for me to buy custom let alone high watt rated resistors. I wonder if I was to shove one of these into a aluminum conduit tube would it increase the power rating.
I expect it would, as "FlingShotsman" said there are thermally conductive epoxy compounds used for potting wire wound resistors. Combining that with alloy tube should make a decent improvement for thermal temps. eBay or Mouser or RS (not radio shack) all sell high watt wire wound resistors and ship global. Even the ones off eBay for a few dollars have performed well for my uses.
Yea I hate ebay, had to many mishaps let along takes a month for it to arrive since 90 percent of the time it comes from China. All the local places want too much for shipping and have to spend a lot for it to be worth the shipping.
For some people; electrical circuitry is an art form that they take pride in, I one day hope, to be able to make any kind of circuit from virtually anything... I could make my own transistors. And I mean in a snap situation.
Another reason is you usually can only buy them online now. So you pay 1 dollar for the resistor and 10 dollars for shipping and handling. Thats why I'm here.
big, what kind of cement did you use I would like to know the name of the gypsum paste you used, what is lime? ...
plaster, he said. In english speaking countries it is known as "plaster of paris", or just "plaster". It's the stuff they make cheap statues out of.
Nice tutorial! I guess however that both resistors will act somehow like an inductor. Is that true, and if yes,do you need to compensate that behaviour?
Because the coil does not have a iron or ferrite core the inductance would be next to nothing. It would be fun to test though. Perhaps you've given me an idea for a future video :)
Yes, wire wound resistors do exhibit some inductance and can't be used in places where that will have a detrimental effect on circuit behavior. Characterizing a few of them would indeed make an interesting video!
+FlyingShotsman Yes , your right and even carbon film or metal film resistors have inductance, albeit much lower. Thats why my tube amp im building deliberately makes use of wirewounds to act as an extra filter choke. The only non inductive resistors are carbon composite, and these are extensively used in RF circuits where low inductance is critical to their operation.
You could buy aluminum, or copper tape, and wrap the block with it, it would serve as an EM shield since the inductance should be low.
Wrapping around in this form, will remove the inductance th-cam.com/video/j4u8fl31sgQ/w-d-xo.html
Great video! !!! sir I have a question for you I'm wondering if your interested in building me a heating element. .. To simplify things I'm looking to reach a temperature of 36c of roughly 5oz water however it must be battery operated with 9v batteries or less . I've seen similar set ups on you tube but I would like it professionally done that's why I'm reaching out to you . please get back to me thank you.
Sounds interesting. Unfortunately I won't be able to help you out with construction at this point in time :)
How can one makena 200 watt resistor. ?
Can one use say 4 resistors at 50w?
I had a crazy idea a while back of making a "revolver" regulating circuit. Based on the physical principal of V/t in switching supplies where they average out the voltage by cycling off states. Only in this case, you cycle components instead. If you "revolved" which resistor was being used at any given time, you almost definitely could get away with cheaper smaller parts. I was thinking of applying it in voltage regulators which have a 1 amp rating. If you revolved 10 of them you could probably cycle 10 amps briefly through each one for one second. Then hopefully after 10 seconds, 1 second for each component, you could then burst 10 amps through for another second and fire off each one down the line. Would be very cool if it worked!
Why do you need the sand?
In a nutshell it adds bulk to the mixture. Similar to how gravel is used in concrete mixes.
good idea
hi.. if i have 10ohm 100w and i need upgrade to 400w for my project. can i use same resistor and make new ceramic cover? any calculation for ceramic cover size?
Man, that is a great question. Since no one answered it, my advice would be to put thermal compound on top and plop a big ol' aluminum heat sink on there with a fan. It works for power supplies up to 1000 watts, so why not in your application? Just uh...test it outside for a few days in case it catches fire. ;)
PS Use metal universal clamps to mount the heatsink tight.
@@peterlamont647 hi thanks bro😊..i just use 10ohm 150w with big aluminium plate as base and cooling fan..so far run over 1 hour all function well..👍🏻
@@zulboy85 Perfect! I love it when a plan comes together.
I was actually surprised with the power rating. I was expecting the diy would be higher/much higher then 5W since there is a lot more mass to dissipate all that heating.
The only diffrence is how long it takes to warm up/cool down.
cool!
And always use cold water on plaster of Paris because hot water makes it set up too fast
Thx, GBU
Well, if you have a multimeter there really isn't any need to do any calculations at all.
Hello Sir i Am Abhishek Can I do some qutions you
You didn't mention 3rd reason for learning this: Post Apocalyptic prepping ;)
well they all kinda were years ago...roughhhh like that...that's newerrr and china playing with cement and idk a more even porous smoother composition...no it don't really matterrr you'll still get years out of it so it is what it is etc lol.
The way you wound it, isn't it going to become an inductor
Yes, it will have a bit of parasitic inductance. But it wont be a lot, as there is no ferrite core
tytytytytytyytyt
Nichrome wire is already a resistor.
Good👍
Wow 👌
YOU TUBE robotizado con cd 4017 , ne 555 pilotos
El plano esta bajo el video. Andre Troll Kaiser
THAT CALCULATOR IS NOT SHOWING ACCURATE ANY OTHER LINK OR FORMULA IS THERE TO CAL GAUGE WE NEED BASED ON RES
Did u just "say pecking tape"
packing tape.
Packing tepe
Pegging tape. ;)
cement and is wirewound...smoked that one that one in the b52 sorta cathode bias, but not exactly.. cathode return shit but more volatile etc lol....one in it just old..lol...have an excellenttt replacement Vishay/Dale like Yageo thing lol.
Jeez, just how cheap are you? What's your time worth?
These things cost a couple bucks.
THANKS
5 watts is 5 watts.
I tried to explain that to a guy that was trying to hard-sell me a more expensive electric space heater. He tried to tell me that it was more efficient, lol. After we argued for a bit I couldn't help but ask him if he was being paid commission; he swore he wasn't. I was irritated that he thought he'd dupe me, but, thinking back, he might have actually believed what he was telling me.
Yes there are plenty of scams out there. Knowing even the basics about electricity has saved me and I'm sure other people. No matter how you cut the cake, 5 watts is 5 watts like you said. :)
Well its not the same thing. A space heaters efficiency is based on how quickly the unit can heat the room to the desired temp. So if you have two 100 watt radiators, they will heat up to the same temperature, but if one has greater surface area, it would heat the room up a bit faster and therefore be more efficient because you wouldn't need to run it as long.
Even if the surface area is smaller, where does the energy go?
The unit with less surface area heats up to a higher temp, but all of that heat energy winds up in the room eventually.
The kilowatt*hour of heat energy into the room is the same regardless of the electric heater chosen.
If it heats up a room faster, then it's drawing more current and using more energy while it does it. The cost is the same. It's not more energy efficient.
So pink...so plump...so gooey...such clean delicate fingers. Now thats a manly man !
Makes you wonder how they make them in China for 99p for 10 and free postage! 😂
Cool but you made an inductor not a resistor. The wires should be parallel to each other..
TediCreations this is how all wire wound resistors are made. Yes there will be some induction in the resistor, however it acts as a resistor for most corcuits because the coil is so small without a core. The company I work for makes resistors and I've seen this process plenty of times. If you need proof just watch one of the countless videos showing what's inside a higher wattage resistor, you'll find many made from potted ceramic or epoxied into an aluminum extrusion the second of which is what my company makes mostly.
yes they do wind it but they first fold it in half so that it decrases the resistance@@lazyh-online4839
*inductance
@@InventTwig not all of them, many if not most are just a single coil wound within a ceramic case encapsulated within the resin core of an aluminum heat exchanger. I worked on every step of this process besides the resin molding for over 2 years before our management changed hands are everything went to $#!t.
Just one question: why?