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induction heating

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Looking for some info on the pros cons and limitations of this type of heating. Does the material have to have an equal cross section? (flat bar?) Are the coils easy to fabricate? I know I have more questions I cant remember. Maybe somebody owns one and can give a report?

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I have had some exprience with induction heaters. Coils are easy to make if you have a modern solid state machine as the machine will automaticaly retune itself for the coil. Coils can be made in virutally any shape. They are limited in the size of coil both length and diameter as they are part of the tuned circuit and are limited by the machines tuning range.

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can these little fellows be used for heating stacked billets for damascus (pattern welding) use - I vaguley recall that the gaps in the stack would prevent the induction field doing its job right... ????

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id look into the power consumption of one of those things and there durability befor i would shell out the money for one.

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Propane is getting very expensive. Another huge benefit is a cleaner working environment. I know i feel pretty woozy after feeding my gas forge after a solid day. Those days usually involve productions jobs which is where this heater will shine.

Neat Guy - thanks for the link. How did you get pricing and for which model?

So, for a flat bar you would fab a flattish looking coil sequence for the required length of heat?

need more info.....

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The model was sp15. I emailed them for the price. I have since used a different machine and would sugjest that the sp15 is not the best for blacksmithing; the frequency is too high.

A flatish coil will work; I believe that I have seen a coil that is "C" shapped so that the edge of a knife and be heat treated although I am not sure where I have seen it.

The length of the heat is kind of limited; but, because of the rate at which the material heats up you can feed the the bar through the coil and get longer heats. Also you can heat treat in an inert atmosphere and get no scale.

Also the machine consumes large amounts of power only while heating. I think these are the same units sold by OC tool but I could be wrong.

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Why not make your own? all an induction heater dose is run High voltage thru a copper pipe. High voltage power supplys DIY
Sorry if i blow your minds out the door, but mine needs some company.

I'll post some pictures once i finish mine

PS: Old computers have Almost everything besides the truck ignition coil, i can get the schematics for the one i'm working on.
To quote so many blacksmiths "we're blacksmiths, it should take us less time to make it than to talk about how to!"

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Propane is getting very expensive. Another huge benefit is a cleaner working environment. I know i feel pretty woozy after feeding my gas forge after a solid day.


If you are feeling "woozy", your ventilation needs to increased.... Propane (even "burned" propane) is displacing the ozygen in your forge.... VERY DANGEROUS!.....

I run a fan unit up in the eave of my forge whenever I have either forge running, just to be safe.... same situation when welding indoors as well....

---------------------------------------------------------------------------------------------------------------------------------- This safety reminder has been a public service announcement of the Save Our Blacksmith association. SOB has chapters located all over the world. Contact your local chapter and become a SOB member today!

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I saw a demo useing induction heating (nwba fall conference darel nelson gary eagle) . It looked good after the initial cost (i heard 5000 +) the electrical cost wasnt bad according to demonstrator...it did give nice localized heats and fairly quick! i think it could work for some things but not everything ..not sure about forge welding ...but industry uses um alot... na I like the smell of coal!!!!

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Yeah it is just a heating tool like the rest. Not like I would get rid of the oxy acetylene or anything loco. Sure would be nice to walk over and get a yellow heat on a hunk of bar stock without having to fire up a conventional forge. And repeat. It will really shine when you design something for a less "influential" client who wants some forged details. Speed = more cheap.

When I said "woozy before I meant that I know my propane forge isn't doing my lungs any favors, not that it makes me ill.

As for forge welding I am told it is easily obtained without flux (another lunger). Quick heat times means limited oxidizing.

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As for forge welding I am told it is easily obtained without flux (another lunger). Quick heat times means limited oxidizing.


Forge welding can be done in a completely inert enviroment so oxidation would be essential eliminated.

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Our Ferrier is using an induction heating machine (that is traditionally used for continuous manufacturing processes) with great success in forming shoes. It is difficult to make a coil that will complex and multi-dimensional shapes effectively, but some of the new machines will allow the use of simple high temperature wire for the inductor iTherm Technologies - Revolutionizing Induction Heating and therefore coils can be made on the fly.

As previously pointed out here, the induction really shines when you have multiple identical pieces to heat (or reheat).

The heating is incredibly fast and efficient, sometimes too fast for the material to tolerate, so be sure to throttle the more powerful generators back when necessary.

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I went ahead and got one of the 15kw units sold by Off Center tools. I use it a ton. It is all about efficiency. When the forge is off, its off. With the gas forge i try to do things very quickly because i know all that expensive gas is going up into the sky (and I'm wicked thrifty). With induction I have the luxury to take that extra step or two and it shows.

Induction is more versatile than you might think with odd sizes and such, you just have to plan ahead.

If i were going through the learning stages of the craft again I would DEFINITELY get an induction forge before any other major tool. Yes, including a trip or air hammer. The luxury of having a near instant yellow heat makes your arm a lot bigger.

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Off center products - run by Grant Sarver (sp?) offers an induction forge for about $2600. I believe that you have to also purchase a TIG water cooler system for about $500.

Some of the nice things about with this forge is:
1.) a flexable wand coil. You can leave work clamped in the vice and 'wand' the coil over the work to take a heat. You could also 'wand' the center of large plate
2.) and open 'C' coil allowing the edge of large work to be put into a coil.

I have used one of these forges at Darryl Nelson's school when I teach there.
It runs on a 50 amp circuit.

1 inch bar for dead cold to yellow (not orange) about 45 to 60 seconds AND you can hold the bar with your bare fingers to within 4 inches of the heat.

Punched holes, upset square corners, upsets...
If I had a job that could justify the expense, I'd get one!

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One thing to mention concerning heating time is that a reheat is about 1/3 that of the initial (dead cold) heat.

There's also a timed control for a retaining heat so if you are doing a hundred tenons you can set the machine on full to achieve a forging heat and then feather it back to a way lower power draw to retain your color and have it waiting for you when you finish the previous piece.

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I was watching a YouTube video posted in another thread here on IForge, and ran across some videos of induction heating similar to this one (there are several):

YouTube - DIY 600W induction heater

So it occurred to me, would it be practical to use induction heating to heat metal for blacksmithing? I know it isn't the least bit traditional, but it might be a clean, low cost (in terms of electricity versus coal) way to heat up stock for a bladesmith. Heck, if it would work, you could even run it in a garage or something where you couldn't run a regular forge.

Sorry, I made the mistake of not looking/searching the forum first. There's a thread already on this topic:

IForge Thread

Edited by 2K_Kid

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S'okay 2K, it's a good subject to discuss.

I'm holding off till they get a bit more economical to buy myself. If I were into electronics I'd build my own but when it comes to electronics I can't keep the smoke in.

Frosty

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I know two smiths out here who use the Off Center induction forge (the one Grant Sarvers sells through Kayne & sons/ Blacksmith Depot)

They really work well for certain things. Making a local heat to bend something, Doing detail chisel work such as animal heads. Even heat treating tools and blades.

I would guess that with a good assortment of coils you could do most things with it. If your serious contact me off list and I'll get you in touch with someone who is running one and could really answer some real world questions.

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Why not make your own? all an induction heater dose is run High voltage thru a copper pipe. High voltage power supplys DIY
Sorry if i blow your minds out the door, but mine needs some company.

I'll post some pictures once i finish mine

PS: Old computers have Almost everything besides the truck ignition coil, i can get the schematics for the one i'm working on.
To quote so many blacksmiths "we're blacksmiths, it should take us less time to make it than to talk about how to!"


high current not voltage :(

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Excellent ideas... blacksmiths in th e21st century?? the toolmakers back on the edge of technology again!!

Can someone give the short version on how induction works?? Have read some.. but having trouble cutting through techno-jargon..

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Excellent ideas... blacksmiths in th e21st century?? the toolmakers back on the edge of technology again!!

Can someone give the short version on how induction works?? Have read some.. but having trouble cutting through techno-jargon..


high current in the heating coil creates a very strong magnetic field

this field in turn produces high electrical current in the piece to be heated...like a reverse electric magnet.

the hi current flow in the work piece heats it up just like running current thru an electric heater.

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high current in the heating coil creates a very strong magnetic field

this field in turn produces high electrical current in the piece to be heated...like a reverse electric magnet.

the hi current flow in the work piece heats it up just like running current thru an electric heater.


I'm curious now, I figured that it was some kind of field, and obviously running a high current in loops will create a magnetic field. But how does this boil water or melt copper or have an effect on other non-ferrous material?

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Basically a high amperage electromagnet induces an equal magnetic field and current, and from the items resistance it gets hot? Thats so cooolll!!!

Cross Pein, from some of the things I have read you can magnetize anything if you have a strong enough field, the pic i saw they had a frog suspended in th ecenter hole of a huge e-magnet

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