monstermetal

Tell me about your Induction forge

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And that right there is why I'll probably buy the 25. I want a semi-moveable rig and all ready have a 4 gal cooler lined up. Bigger in this case is not better



beep....beep....beep...

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Thank you Grant. Can you post a balpark price so I have an idea of how much to save and will it function off a rotary phase converter or does it need "pure" power due to the electronics?
Monster, Are you going for the 220v one to be able to relocate in the future?
Rob


$5,000. Rotary works fine, that's what I run mine on.

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Thank you Grant. Can you post a balpark price so I have an idea of how much to save and will it function off a rotary phase converter or does it need "pure" power due to the electronics?
Monster, Are you going for the 220v one to be able to relocate in the future?
Rob



Probably not.... I have a whole area full of 480V machines and it would be easier for me to pull a new 480 line than 220... plus it makes the cord more managable..... I figure If I move Im gonna have to deal with 480 again anyway

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Couple of observations on my 18kw heater.
I had a request from a fellow smith that I met at Quad State this year regarding heating some 1/2" x 4" flat stock. When I got back to my shop I wound a coil and gave it a try. I was able to raise 3/4" of an inch length of the 1/2" x 4" stock to forging temp in about 40 seconds, and heated over 2" of that same stock in about 2 minutes.
With a different coil you can heat 3/4" of 5/8" round to yellow in about 5 or 6 seconds. Coils can be wound and tried in about 15 minutes, and you will find that you will have quite a few coils in a month or so of working with your heater.
18 kw input requires 75 amps at 240 volts. Thats pretty much the max for 220/240 supplies. Higher power inputs will use higher voltages to keep the current down to a reasonable level. If you doubled the voltage of my 18 kw system and kept the current the same, (which is way easier in electronic devices) you would then have a 35-36 kw input machine. Not saying that you can do that... more of an illustration...
Most all of the inverter induction heaters use a phase lock loop oscillator to adjust the machines frequency to match the coil that you have installed. Most of my coil designs operate at no more than 50 kilocycles or so.
Someone had mentioned surface heating and was wondering how effective these machines were at heating materials for forging. Using induction heaters to surface harden camshafts and the like requires higher frequencies and MUCH higher power levels to quickly heat heat the surface only then and self quench, and even there I would suspect that additional quench might need to be harden the surface. At lower power levels, like the 18kw maximum system that I have, even the surface heating that my system creates will heat the stock though to the center in short order.
I had commented before on engineers trying to talk me out of induction heating in the past... "It won't work unless the coil is matched to the stock" What they were saying was it won't work at a level of efficient and speed that matches the production requirements that they expect, but I have found them to be very useful in spite of the engineers predictions.

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I had commented before on engineers trying to talk me out of induction heating in the past... "It won't work unless the coil is matched to the stock" What they were saying was it won't work at a level of efficient and speed that matches the production requirements that they expect, but I have found them to be very useful in spite of the engineers predictions.


You've hit the nail on the head there courtiron. To get irregular shaped work into the coil, I often use really poor coupling ... say 3/4 inch spce from work to coil ... and then push about 1000A through the coil cos only a small % of these Amps are transferred into the work. It still gets hot pretty quickly . To an engineer it's probably real poor procedure, to me it works ... that all I care about. I don't think it will daamge the machine. There are some losses due to resistive heating in the coil and the 1000 Amps but essentially all the electricity you are paying for is what is used to heat the work. Most of the 1000Amps is out of phase with the voltage. The more powerful a machine you have, the looser coupling you can get away with .... I think!

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Im making a trip down to Grants tomorrow to gather up my machine.... Its been there for a few days and I have been itching to play... I did buy the 25KV mostly because the cooling tower for the 35KV got to be a much more involved thing than the 25... I really didnt want to spend the several thousand a chiller cost or have to figure out how to have a mobile 50 gal cooling circuit..

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Im making a trip down to Grants tomorrow to gather up my machine.... Its been there for a few days and I have been itching to play... I did buy the 25KV mostly because the cooling tower for the 35KV got to be a much more involved thing than the 25... I really didnt want to spend the several thousand a chiller cost or have to figure out how to have a mobile 50 gal cooling circuit..


Monster M, how are you liking your 25?
Robert H

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Its really amazing how much I use it... You know its one of those things that until you have one it seems like a luxury, but since having one in the shop I dont think I would want to operate without one. It makes many jobs reasonable to do that would have been marginal in the forge... I just built some peg racks that combined had about a 100 pegs about 6" long made out of 3/8 round, In the past I would have left them straight because it would have took to long to bend a " L end" on them... but now with the induction forge I could forge a end bit on them so quick it would have been silly not to do it, I bet I forged all 100 of them in less than 20 minutes... took about 10 sec each to heat and about 5 hammer blows to forge.. so in the same time it takes to get the forge hot and loaded with the first batch the job was done... I have been doing a organic branch railing and adjusting and fitting bars with the induction machine is ridiculously quick, its allowed me to devolve a couple of new elements that are really quick to make as well... I do wonder about the bigger machine but I dont regret buying this one. It might be at some point I'll buy a second larger machine but not anytime soon.. One thing is for sure, if your goal is to make money, I dont think there is a single addition to a blacksmith shop that will put more dough in your pocket than a induction forge.. Its a beautiful thing ;)

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Its really amazing how much I use it... You know its one of those things that until you have one it seems like a luxury, but since having one in the shop I dont think I would want to operate without one. It makes many jobs reasonable to do that would have been marginal in the forge... I just built some peg racks that combined had about a 100 pegs about 6" long made out of 3/8 round, In the past I would have left them straight because it would have took to long to bend a " L end" on them... but now with the induction forge I could forge a end bit on them so quick it would have been silly not to do it, I bet I forged all 100 of them in less than 20 minutes... took about 10 sec each to heat and about 5 hammer blows to forge.. so in the same time it takes to get the forge hot and loaded with the first batch the job was done... I have been doing a organic branch railing and adjusting and fitting bars with the induction machine is ridiculously quick, its allowed me to devolve a couple of new elements that are really quick to make as well... I do wonder about the bigger machine but I dont regret buying this one. It might be at some point I'll buy a second larger machine but not anytime soon.. One thing is for sure, if your goal is to make money, I dont think there is a single addition to a blacksmith shop that will put more dough in your pocket than a induction forge.. Its a beautiful thing ;)


Thanks Monster! I'm thinking about either a 15 or 25, and leaning towards the 25. I'd use it for both knives and generalized blacksmithing (meaning art stuff, kitchen/bath items, but nothing really big and heavy like your railing). I think the 15 would handle all that I mentioned, but I do have several hundred pounds of W2 I got from Don Hanson, and the 25 would be handy for that also.
Would you happen to have a photo of your setup? I think you were having some issues with cooling in some earlier posts.
Thanks!!
Robert

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I'm not sure of the prices your side of the pond but if these are typical and you've got the electric supply and the choice is the 35 or 25 I'd definitely say get the 35 for the extra $1000. Especially so given the the 35 has a 100% duty cycle and the 25 an 80%. It's that old saying you can do anything on large lathe/anvi//forge/etc/etc that you can on a small one but not the other way round.

It seems in theory that those of us with 220v might be able to run something larger than 15 using a step up transformer -- but I don't know. With 220v and 200amp service, I would love to dedicate about 180 of those amps to a large induction!

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Grant,

How big of a phase converter is needed to run the 25KW 3-phase unit? Do you need your 40HP converter or can you get by with something smaller?

-Tod

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How big of a phase converter is needed to run the 25KW 3-phase unit? Do you need your 40HP converter or can you get by with something smaller?

Heard back from Grant -- you need a 30 hp converter to run the 25kw heater.

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Ok here is my confession..

but to say I need a 200 ton forging press or a 3B Nazel to conduct business would be a flat out lie.


So your selling me your 200 ton press then...well,sniff, thank you, its the best thing anyone's ever, sniff, done for me....

Since there is a certain desire for the induction units I suggest you go play with one of the 25Kw units and then the 35 and see which makes you more happy.

Thoughts from someone who owns a non-running 50kw unit:
So I was impressed with the 3,000hz 125kw unit the university has here in Wisconsin so I looked into the tech...interesting stuff there. Such a unit would be about $150,000 new..give or take and melt much metal and heat about anything you care to heat. After some more research and calls and emails to India,China and parts of the US I began looking for a 3,000 hz unit rather than the higher freq units which seem to be more common.
I want to melt and heat and because there is a drop in power to the part when it goes through the Curie Point I figured I'd wait and see what presents itself.
A few years passed and I heard of an auction in Massachusetts ,five days after it happened, and tracked down one of the 50Kw 3,000 hx Ajax units..which broke in shipping and I had to loge and insurance claim...so now its a matter of feeding it 50Kw of 480 power when I have no three phase. Another year passed and I found a 50kw generator and this year, hopefully, I'll get the natural gas line plumbed to feed the genset to feed the induction unit...so I can heat bars of steel to forge..which I could already do in my $10 per hour propane forge.
I think induction is a wonderful technology, but there are sliding scales of hz rate(lower the hz the deeper the eddy penetration),kw of input,voltage of input, coil coupling and water quality which need to be dealt with.

Larry, the end result is that no matter what unit you get and how you work the coil there will be parts you can not heat efficiently and can not heat at all and some things it will work just peachy on....and you can sell the unit if you wish to get something else later.

Architectural work has completely dropped off in my shop as has some of the other stuff I have done regular...so I am moving toward things I never did regular..teaching,more sword work,more steel-making,more odd bits and pieces.
I used to make these trap net anchors every year for Commercial Fisherman around the Great Lakes..now not so much as their rules are changing as well.
http://www.doorcountyforgeworks.com/Trap_Net_Anchors.html

Ric

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So I just joined the induction club and its a super cool process. It heats metal fast and in a highly controllable way. sadly it took me about 2 months since I bought it to get it up and going. My work load has been heavy, I have been very busy around the shop. All told it took to hook it up about 10 hours of work with the cart. It cost about $6700 total it sort of upsets me when I think about it but Ill deal. This included the steel for cart I built, hoses, fittings,1- 3ph 30 amp plug and outlet a 25 ft 8 gauge 4 wire power the cooler and strain relief fitting for the power cord. I opted for the 25kv unit because I have the power and I like to go bigger whenever I can afford to. I guess it was a bit of an emotional purchase but also I am looking forward to the future. I am wanting to have a cleaner shop and to be less polluting. I have 2 coal forges and a natural gas forge. That sulfurous smoke coming out of my stack just doesn't sit well with me not to mention coal dust the particulates form the forge linings and carbon monoxide. Not that I plan to not use the other forges. I will use the best tool for the job. I do a bit of production forging so I am hoping this will help help me out in that department. I am also looking forward to having a cooler shop this summer. It does get fairly hot here in NY in the summer time nothing like Mississippi but we do get into the high 90's from time to time and it is very humid. Here are a few pics of my machine the last photo is of some test pieces of threaded rod cut offs.

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I have to say what I really like about this machine is it makes forging a more attractive form a dollars and cents perspective. It sort of tips the internal argument I always have around the shop in the right direction towards BLACKSMITHING and away from welding and cold work. I always ask my self what is the fastest way to do this task. More often than not it involves a mig gun and a grinder. Then I go and forge it anyway, leading to me later to reflect on why I am short on cash behind schedule and working on a Sunday. I often think, can I really justify lighting the forge for this one little task. Well now I find my self thinking I can get a good solid heat at the push of a button and in a few seconds so why not forge it its faster than doing it cold. I almost feel like I have a magic heat ray or something like that. Almost as fast as I can think it the work gets hot. You can take a quick localized heat and with minimal scaling as well. I love this thing. It is the first technology I have seen in the past 100 years that makes blacksmithing more economically viable not less. Also it takes nothing away from the skill of the smith yet it increases their efficiency and freedom to experiment. Think about that its pretty amazing. I came home from the shop almost clean the other day and barely sweating that never happens.

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We just got in a 30KVA 50-150Khz Ameritherm unit for zone annealing. Just messing around with it today to make sure all of the systems were working , and put a 1.25" bar in the test coil. Hit start, and it was red in a few seconds. I may have to take an anvil into work, and make a pancake coil for it.

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