25 replies to this topic

[youngdylan]

Finally got the induction heater I've been wanting for over a year. Many thanks to Grant and John N. I also finally got to grips with Youtube.

It's a 25KVA machine, a lot of the ones on youtube are 15KVA. The extra power means it can put a LOT of heat into a bar VERY quickly.

The top figure on the display is the elapsed time. The lower is the current in the coil, this starts around 600A and then gets up to over 1000A.....thats a LOT of Amps....even more are flowing around as eddy currents in the bar .... so it gets hot .... very very quickly

The bar is 40mm diameter.

Note how the heater heats the outer layer of the bar and this heat is transferred by conduction into the centre, rather like an eletrical gas torch.

Note the spark at around 1.20

When I find time to play I'll post some videos showing it being used to make things.

[Mainely,Bob]

Uh-oh,I believe someone just got the keys to the castle and is about to declare a blacksmith`s holiday complete with induction party.
Looks like your vegan girlfriend will be eating salads by herself for a while.You`ll be holed up in that closet you call a shop eating power bars and washing them down with energy drinks while watching steel burn.

Have fun with the new toy Cappy.
I can already see you posting all sorts of new things as you push it to it`s limits(and hopefully not beyond).
Remember to keep the magic smoke inside the box.

[Fosterob]

Wow that looks great, very impressive. What kind of power supply do you need for it?
Rob

[monstermetal]

Mainely,Bob, on 22 August 2010 - 07:55 AM, said:

Uh-oh,I believe someone just got the keys to the castle and is about to declare a blacksmith`s holiday complete with induction party.
Looks like your vegan girlfriend will be eating salads by herself for a while.You`ll be holed up in that closet you call a shop eating power bars and washing them down with energy drinks while watching steel burn.

Now that there is funny

[Fosterob]

I can,t figure out how to cook a chicken on it though ? I guess you could fry it on plate but then no bbq flavor
Rob

[Phil Krankowski]

Heat up a few 1 inch rounds or square and lay them neat, maybe use a few fire brick to contain them. Then take that grill and suspend it over the iron. You should have plenty of heat to cook a bird nice. Add some wet wood chips for smoke flavor

Phil

[Swamptroll]

Do you use fiberglass tape on your coils?

[John N]

Ahhh, blacksmiths, gotta love em! probably the single biggest move forward in efficency for the small metalworking shop since the mig welder and ya'lls working out how to cook supper on it

Ive just got the smaller, single phase induction heater. It really is a magic box that has got my head spinning with ideas how I can improve my (mostly patternwelded) work.

As soon as I get some time to have a proper play ill post up details.

[JNewman]

You can get a induction stove to cook dinner on. We just bought one because our 25year old stove would not fit in the house we just moved into. It has many of the advantages of the induction forge, more energy efficient, FAST heat, instant off, and the burner stays relatively cool so spills do not burn on.

[youngdylan]

Latest videoshows the machine with thinner stuff and being pulled through. Boy is this a quick way to heat steel.

Someone asked about insulating the coil with fibre glass. Nope, it's just bare copper with none of the coils touching. The work shouldn't really touch or short out the coils. The occassional brush seems no problem (see about 0.07 but if you do a big short the machine will just shut itself down. Quick swith off and on and everything is hunky dory.

I'm going to experiment with a sleeve of say 1 or 2 mm ceramic paper between the work and the coil.

By my way of thinking this should

1. cut down on the heat that is radiatied from the work into the coils (and taken away by the cooling water), the work should heat up quicker and the water cooler has less cooling to do

2. You can use a coil that "hugs" the work more closely without worrying about shorting as you pull the work back and forth. This allows a better coupling of energy between the work piece and machine .... faster heating (as if it wasn't fast enough)

I'm going to play around (when I get time) with forge welding DIRECTLY inside the coil as per the good Dr. Sarver

[John B]

Definitely the way we will be going in the future,

Can/will you give more details please if you feel comfortable with imparting the information

Voltage required, single or three phase, ease of availability in the UK, agent to contact for sales, approximate cost of the machine

I used to use an industrial Radyne induction heater for hardening gears etc, and often thought how useful it would be for forging and heat treating hammer faces etc.

Shall have to be careful, nearly got excited there watching the vids and thinking of possible applications, not good at my age.

[John N]

Hi John, Im working through the feasability of selling these in the UK, David has got the 3phase unit, and ive got a single phase for evaluation purposes at the moment.

They are going to get a bit of a workout for a couple of weeks, then off to my electrician for a strip down and study on CE complience. A bit of work to go yet, but im hoping to be able to say if its a yeah or neigh in about a month.

We are also working with the carbon trust, and if I can get CE complience on the units there is a very good chance of an interest free loan over 3 years from them (the fuel cost savings will go a long way to repaying the loan in a busy shop )

[youngdylan]

John B, on 22 August 2010 - 03:11 PM, said:

Can/will you give more details please if you feel comfortable with imparting the information

Voltage required, single or three phase, ease of availability in the UK, agent to contact for sales, approximate cost of the machine

John B

John N's is the 240V single phase and rated at 15KVA, mine is the 3 phase 415 version rated at 25KVA but I'm running from a large (32A) red 3 phase socket with a 32A breaker behind it at the distribution board. Hasn't tripped it yet in a few hours use. Mine does need a good water cooler to use it. I'm posting more of my thoughts over here. Maybe it best to pm John re potential cost .... I've an idea but it's not my place to say!!! What I can say is that it's real good value for professional users and opens up allsorts of possiblities for the hobbyist. As Grant say it great for the garage bladesmith with "neighbour" problems, this tool and a hydraulic press

[John B]

Appreciate the response guys, especially as its in the embrionic stages at the moment, and you have both put in a lot of effort off site, it's time we here in the UK got a bit more flexible and up to date with some more modern practices and embrace them, I know there are commercial suppliers like Inductelec just over the hills in Sheffield who make the industrial jobbies, but whether they would be interested, or more to the point affordable in supplying one man and a dog (retired) outfits like me would have to be investigated, and I don't like wasting peoples time on what may prove to be a futile enquiry.

Good luck to you both with taking this on

I will be following the progress avidly, both here and on the other site.

[youngdylan]

John B, on 22 August 2010 - 05:01 PM, said:

Inductelec just over the hills in Sheffield who make the industrial jobbies, but whether they would be interested, or more to the point affordable

John, about a year or so I was desperate to get my hands on one and it didn't look like I'd be able to get one over here because of CE and stuff. I did some quick and superficial looking around at "industrial" heaters over here. We were talking £10,000's here so it was a non starter for me. These are nowhere near that. Okay so it's made in China (as are probably just about any). That doesn't worry me one iota, as long as the quality control is there. The way I look at it is, these tools are a million miles away from the cheap power tools that flood the DIY market. Up till now it's only been industrial or serious professionals that have used induction heating. These sort of people don't usually buy tools that fail.

Grant Sarver is "The Man" for this stuff on t'other side of the pond, he's had no reliability issues with the ones he's sold. As far as I know he's been selling them for about 5 yearss (maybe more)

Politically it would be nice to buy domestic but if "we" can't/won't produce one small/cheap enough ................ My same thoughts apply to the small Anyang power hammers

PS it's John that may be selling them over here (Grant does so over there). I've just paid my money as a more than willing "Guinea pig"

[Dragons lair]

Fosterob, on 22 August 2010 - 10:48 AM, said:

I can,t figure out how to cook a chicken on it though ? I guess you could fry it on plate but then no bbq flavor
Rob

From what I remember of the induction brazers I saw if ya make a large enough coil ya could do a chicken. Add a few hickory chips for flavor. How about it Grant?
Ken.

[dpcook]

What is the frequency of the AC current in the coil with this thing? You said the transformer steps the current up to 1000 A?

[Nakedanvil - Grant Sarver]

Frequency runs about 30,000 - 100,000 Hz.

[dpcook]

Nakedanvil - Grant Sarver, on 10 September 2010 - 11:20 AM, said:

Frequency runs about 30,000 - 100,000 Hz.

Sorry for posting that question... I was just cruising on a different thread and saw that you had already answered it.

Follow-up question: how is it self-tuning? Is it based on feedback from the coil? I'm assuming that it tries to insure
that you don't get current cancellation in the piece being heated...

Again, forgive my questions. I'm a theoretical genius in the use of induction fields in industrial metals processing
but this is the first time I've thought about the nuts-and-bolts aspects of how these go together.

[dpcook]

dpcook, on 10 September 2010 - 02:02 PM, said:

<snip> I'm a theoretical genius in the use of induction fields <snip>

I just realized that could be taken two ways... Either I think I'm a genius, or I'm a genius
when it comes to the theory... You can pick your own explanation...