Good job! -You might tell folks WHY there's an upper limit on frequency. If you are using the Chinese 1000 watt ZVS induction heater that is so popular, the higher the frequency, the higher the likelyhood of the circuit failing because the Mosfets spend too much time in the linear mode, creating a LOT of heat. Personally, I don't recommend going much over 100 kHertz with those heaters if you plan to run them hard.
Great set of videos! I would be curious to see what your approach would be for heating the same shape but with a split coil, if that makes sense. When your are heating electrodes for plasma, the metal shell used is inside glass, and the glass is connected in line with a vacuum system. So if we use a coil style, the coil has be placed in line with the glass before you seal the glass to the vacuum system. So far there is only one person making a working style induction heater for this process that is not a full coil style and it is called the Annie. It uses a set of split coils, where there are two or so loops on each side and a gap in between where you put the shell. It is very handy in this application and curious of what you would do when facing this situation. The annie is a great tool but we have had it break many times and it's along waiting period for fixes from the supplier, giving its just one person. So hence how I found your videos trying to research solutions for this problem. Thanks for sharing!
id put rock salt into it and shake it as you allow it through the loop by spinning and using gravity to get it the whole way to the other end then flush with water for any salt residue
Depends on the size of the piece, really. Thicker parts use lower frequencies. But melting large chunks of aluminum or cast iron would take a lot of power. See pages 63-64 from references to skin depth and frequency for different materials.
Well, if you put the sleeve on before winding, you'll usually put holes in it from all the bending pressure around the mandrel. OTOH, if you try to put it on after, you have to be careful to leave large enough gaps between the coils for it to fit through. You can do it either way.
Good video but I have a couple questions Why use tubing rather than solid wire? #6 is readily available by the foot everywhere and just under 3/16” diameter. What brass are you annealing that you need a coil that big?
I'm waiting on an ammeter in the mail still, but does the increase or decrease of the inductance raise or lower the current draw of one of the commonly available induction heater boards?
@@silvionannoni5281 Maybe (I would guess so) but there's no way to know without knowing the specs of the ZVS board you're using. You can watch the previous (part 1) video where I go through the details of how the inductance affects your circuit.
Yeah. You'd want to use heavy gauge Litz wire (or at minimum fine stranded wire) for the leads. Depends on what you are going to use it for, honestly. They sell induction bolt heaters that are pretty portable that might be easier to use.
@@TechDregs 😁 Thks ! ... i will receive mine next month, ... with a small crucible, ... but i don't have enough hands to manipulate all parts, moulds, ect ! 🤣
@@windworldwide8840 All depends on how much power you're running through it. It might work fine, but I definitely wouldn't go any smaller than that. Keep an eye on the temps, and if it's not getting hot, then it's fine.
@@TechDregs Thank you very much for the video. Just wounded a dual layer coil for my ZVS (1000W). I used a 4mm OD copper tube (diameter including isolation 4.6mm) and a pipe with 25.4mm diameter. I have choosen 4 turns by two because the measured inductance of the original coil delivered with my ZVS (1000W) was about 1.8uH. On my board there are five 0.33uF Capacitors in parallel. The tip with table salt is awesome and winding was much much easier than thought. Took me not longer than 10 minutes. Now I'm waiting to get out the salt (I soaked the whole coil in a large bottle with warm water) and after that I will hook up the LC-Meter to check the inductance.
Good job!
-You might tell folks WHY there's an upper limit on frequency.
If you are using the Chinese 1000 watt ZVS induction heater that is so popular, the higher the frequency, the higher the likelyhood of the circuit failing because the Mosfets spend too much time in the linear mode, creating a LOT of heat.
Personally, I don't recommend going much over 100 kHertz with those heaters if you plan to run them hard.
I appreciate your videos. Thank you for testing all of this out.
Great set of videos! I would be curious to see what your approach would be for heating the same shape but with a split coil, if that makes sense. When your are heating electrodes for plasma, the metal shell used is inside glass, and the glass is connected in line with a vacuum system. So if we use a coil style, the coil has be placed in line with the glass before you seal the glass to the vacuum system. So far there is only one person making a working style induction heater for this process that is not a full coil style and it is called the Annie. It uses a set of split coils, where there are two or so loops on each side and a gap in between where you put the shell. It is very handy in this application and curious of what you would do when facing this situation. The annie is a great tool but we have had it break many times and it's along waiting period for fixes from the supplier, giving its just one person. So hence how I found your videos trying to research solutions for this problem. Thanks for sharing!
Try vibrating coil with Electric toothbrush/massager etc to remove sand with water or air.
id put rock salt into it and shake it as you allow it through the loop by spinning and using gravity to get it the whole way to the other end then flush with water for any salt residue
very good video, loves
Very cool video series on your annealer build. I assume you ended up sticking with 10x 0.33uF capacitors?
Yes, from what I remember, those were easy to find in higher frequency versions without doing special orders. Other values were less common.
If inductance is used to melt aluminium in a crucible is there a preferred frequency. Also cast iron. Thanks great video slow an easy to follow.
Depends on the size of the piece, really. Thicker parts use lower frequencies. But melting large chunks of aluminum or cast iron would take a lot of power. See pages 63-64 from references to skin depth and frequency for different materials.
I wonder how sugar instead of salt would work, then you could warm up the coil and flush with hot water to clear the tubing....
Might be worth a shot if that's what someone has to work with.
Thanks a lot!
Thanks for the video. When do you put sheathing on the pipe? Before or after coiling process?
Well, if you put the sleeve on before winding, you'll usually put holes in it from all the bending pressure around the mandrel. OTOH, if you try to put it on after, you have to be careful to leave large enough gaps between the coils for it to fit through. You can do it either way.
Good video but I have a couple questions
Why use tubing rather than solid wire? #6 is readily available by the foot everywhere and just under 3/16” diameter.
What brass are you annealing that you need a coil that big?
Heat. You need to water cool the coil, or it will get very hot due to the brass radiating and resistive heating.
Hi! What coolant did you use?
Distilled water or some kind of antifreeze?
It's just PC coolant.
I'm waiting on an ammeter in the mail still, but does the increase or decrease of the inductance raise or lower the current draw of one of the commonly available induction heater boards?
Lower inductance will tend to increase current. Lower inductance gets closer and closer to just being a straight wire short.
How long is the tube? 35 inches?
Yeah, approximately.
@@TechDregs Today I have make it! 😃
Hello, if uH is 0.544/0.550 is it ok?
I came up slightly narrower than yours… 17.90 mm internal
But I think yes because the frequency is 118.785 kHz
@@silvionannoni5281 Maybe (I would guess so) but there's no way to know without knowing the specs of the ZVS board you're using. You can watch the previous (part 1) video where I go through the details of how the inductance affects your circuit.
Hi ! ... is it possible to have the coil away from the zvs ? with a handle ? .... electrical wire between the zvs and the coil ?
Yeah. You'd want to use heavy gauge Litz wire (or at minimum fine stranded wire) for the leads. Depends on what you are going to use it for, honestly. They sell induction bolt heaters that are pretty portable that might be easier to use.
@@TechDregs 😁 Thks ! ... i will receive mine next month, ... with a small crucible, ... but i don't have enough hands to manipulate all parts, moulds, ect ! 🤣
@@TechDregs i would use 1 meter 4mm2 audio wire from the zvs to the coil tube ... with cooling. do you have any advice ?
@@windworldwide8840 All depends on how much power you're running through it. It might work fine, but I definitely wouldn't go any smaller than that. Keep an eye on the temps, and if it's not getting hot, then it's fine.
will that coil work with aliexpress 1000W ZVS? I think we should be on 1.25uH according to specs. Thanks in Advance!
Please see the previous video on how to design/specify a coil for a particular circuit. It goes into all those details.
@@TechDregs thanks
@@TechDregs Thank you very much for the video. Just wounded a dual layer coil for my ZVS (1000W). I used a 4mm OD copper tube (diameter including isolation 4.6mm) and a pipe with 25.4mm diameter. I have choosen 4 turns by two because the measured inductance of the original coil delivered with my ZVS (1000W) was about 1.8uH. On my board there are five 0.33uF Capacitors in parallel. The tip with table salt is awesome and winding was much much easier than thought. Took me not longer than 10 minutes. Now I'm waiting to get out the salt (I soaked the whole coil in a large bottle with warm water) and after that I will hook up the LC-Meter to check the inductance.
Getting out the salt is not so easy as thought... I could not find connectors to try it your way.
This is what I used: www.amazon.com/Minimprover-Swivel-Connector-Adapter-Fitting/dp/B08ML1MZNC/