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{{inductioninfo}}
The [[Tools/25kW Induction Forge|Forge]] can heat beyond 1600 ºC, uses high powered electronics, has the risk of igniting metals and many other hazards, for that reason an [[Tools/25kW Induction Forge|Forge]] is compulsory before using the forge. Induction normally takes about 2 hours.
== Safety ==
{| class="wikitable"
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! Topic !! Detailed Contents !! Rationale
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| Suitable Clothing ||
* Old Clothes, they're going to get burn spots
* Overalls are best
* Avoid synthetic fabrics, they burn and melt
* Heavy, Steel Toecap boots are a very good idea, but at least stout shoes, no sandals, no open-toed shoes
|| Suitable clothing is essential for safety
|-
| PPE Required ||
* Goggles are required at all times while forging. Hot scale can fly off the metal as you work it.
* Welding gloves or heat-tolerant work gloves - dop rods will get hot!
* Anti-vibration gloves if you're doing a lot of forging
* Ear protection while hammering
|| Good PPE to protect from specific hazards
|-
| Workshop hazards and mitigation ||
* Good air circulation needed - doors open but only slightly, monoxide hazard and detectors - immediate shut-down and evacuate if they go off
* Heat buildup in the laser room
* Slip hazard from quenching oil
* Hazards of metals high in nickel, chrome, cadmium etc, and protection needed
* Arc-eye hazards of welding
|| Hazards other than fire that could impact the rest of the workshop
|-
| Fire risks ||
Fire and burns are the single largest hazard in forging.
* Clearing the area around the forge of all flammable materials, especially sawdust and the bins
* Be aware of hazards of flammable vapours and solvents, keep well away from the forge
|| Things that can cause fire
|-
| Dealing with Fire ||
* What types of extinguisher to use on what sort of fire- CO2 or dry powder for electric fires
* Using fire extinguishers
** Calling for help, alerting people
** Consider if the fire is small enough to fight
** What types are suitable for what fires
** We cannot extinguish metal fires, use the vermiculite to smother or place on a safe surface
** Fire hazard from quench oil
** How to use an extinguisher
|| Have to be ready to deal with a fire if it happens
|-
| Burn treatment ||
* Evaluating the seriousness of burns
* Basic burn first-aid
|| Shouldn't happen, but it's always a risk and people need to know how to deal with that
|}
== Theory of steel forging ==
[Draw the iron-carbon phase diagram on the board covering 0-1.5% carbon and 0-1500 ºC]
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| States of steel and their properties ||
* Ferrite - Soft, workable
* Cementite - Hard, Brittle
* Pearlite - Soft layered structure, normal resting state for most steels
* Austentite - High temperature structure, soft, malleable, workable, dynamic structure
* Martensite - Not a natural structure, formed by heat treatment, very hard, very strong quite brittle
* Spheralite and Banite - Useful industrially but we can't make them here
|| Need to know the basics of how steels respond to heat in order to know how to work
|-
| Critical Temperature ||
* Is at least 727ºC and can be more depending on %age carbon
* Steels are generally magnetic below critical and non-magnetic above it.
* Steel is formed above critical temperature and plannished below it.
* Magnet can test for critical but learn to use colours
* Other alloys can have different working temperatures
** Bronze is much lower
** Stainless steel is higher
** Damascus steel is much higher
|| Vital concept for forging
|-
| Hot hardness || Is a measure of how easy to forge the material is, small changes in composition can cause large changes in hot-hardness || Key concept in working with different steels.
|-
| Heat treatment processes ||
* Annealing
** Heat slowly to above critical temperature
** Soak till even temperature
** Cool as slowly as possible, utilising vermiculite
** Some steels have a thermal "no-go" zone where you can't linger, check the datasheet
** Results in a soft steel that's cold-workable
* Normalizing
** Heat slowly to above critical temperature
** Hold it there for some time, time depends on thickness and your patience
** Cool reasonably slowly
** Relieves stress and lowers risk of cracking subsequent treatments
** Not all steels can or should be normalised
* Hardening
** Heat to specified hardening temperature
** Quench in air, oil, water or brine according to specification sheet
** Leaves steel very hard and very brittle
** Too slow cooling leaves metal soft, too fast will crack it
* Tempering
** Heat to temperature and time specified in datasheet
** Reduces brittleness in hardened steels to make them useable
|| Basic ways to change the properties of steels
|-
| Heating Errors ||
* Working a steel too cold - Very hard work and risk of cracking
* Working a steel too hot - Hard to control and risk of crumbling from hot-shortness
|| Knowing the serious errors and how to avoid them
|}
== Practical Forging ==
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! Topic !! Detailed content !! Rationale
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| Work Holding ||
*Tongs
** Type of tongs we have
** Consider where to grip
** Keeping the tongs from overheating
** You can ask for someone to make special tongs if you need them, or make them yourself
* Dop Rods
** Much easier work-holding especially on items where you only work on one area at a time.
** Welding onto the dop rods
** Emphasize the need to use a LOT of weld material
** Need to normalize the welds
*** What happens if we're not hot enough, or too hot!
** They are GOING to break, what to do when they do
*** Watch for starting of cracks
*** DO NOT TRY TO CATCH THE HOT METAL
*** Pick it up IMMEDIATELY with grips, place onto hot-safe surface
*** Allow to cool at least partially before re-welding
*** Grind off any loose material and re-weld
|| How to hold work in a safe and effective way
|-
| Examining and setting up the Forge ||
* Describe the forge and it's parts
* Visual inspection for loose pipes, coolant leaks & electrical faults
|| How to get the forge set up
|-
| Powering the Forge ||
* Plug it in - Both the 3-Phase for the forge & regular plug for the coolant.
* Vent the radiator to remove air from the system.
* Turn on the coolant, followed by the induction forge
| Hammering technique ||
* Holding the hammer
** You need a grip tight enough to keep control but,
** Avoid a "Death grip" on the hammer, you'll wind up with sore fingers and it won't help
** Wear welding gloves for occasional use to protect against vibration, if you're forging regularly then get specific anti-vibration gloves
* Using your body
** Find a comfortable position, the anvil might not be the right height for you but do the best you can
** Aim comes from your arm, power comes from your shoulder
* Striking
** Positioning yourself so that the hammer strikes just as it come parallel
** Never strike directly on the anvil, they're both hardened and may crack
** Using a light tap every few strikes to "reset" you position
** What the different zones of the anvil do
|| Avoiding RSI and other injuries from the process
|-
| Shaping metal ||
* Heating to a suitable colour, testing with magnet if you need to
* Don't touch metal to anvil till you're ready to strike
* Just get the feel of beating on the metal, try both hammers, see what it's like and don't assume you should use the heaviest you can
* Consider the shape we're working towards
** The need to come to both dimensions at once and not over-work in one direction
** Correct any error immediately, don't let them grow
** We can't fix over-thinning
* Looking at the metal as it cools, seeing what needs to change
* Drawing out using small hammers, large hammer on step, large hammer on side, edge of large hammer
** Cycling draw out and flatten
* Keep thinning, flattening, drawing out till target shape
* Try to get the surface nice, so you can do less grinding
** Plannishing below critical
|| Actually moving metal around with the hammers
|-
| Normalize and anneal when done ||
* The need to normalize after forging to relax the metal
* Annealing to make it more workable for subsequent finishing operations
* Normalize for at least 2 cycles and maybe more for complex or precise shapes
* Fix geometry before cycles
* Using the vermiculite to slow down cooling to achieve maximum softening
* Furnace cooling is also an option and may be more controlable
** Using thermocouple to avoid any no-go-zone the metal may have
|| Post-forging treatments to make usable parts
|}
== Shutdown and clean up ==
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| Shutting down the forge ||
* There should be no cooldown time needed. To be sure, leave coolant on while putting away the anvil - this should be sufficeint time for any residual heat to dissipate.
* Re-cover the forge and wheel the forge back to its storage.
* Sweep the area and return any displaced equipment to origional positions
|| Safe shut-down when done
|-
|| Putting everything back for the next person
|-
| Problems ||
* If you saw any problems with the forge, contact the maintainers
* If you got any good photos, upload them to wiki or post on Discord!
|| Keeping people updated on status
|}
[[Category:inductions]]
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