Tools/forge/induction: Difference between revisions
imported>Stever |
imported>Stever |
||
Line 131: | Line 131: | ||
** Emphasize the need to use a LOT of weld material |
** Emphasize the need to use a LOT of weld material |
||
** Need to normalize the welds |
** 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 |
** They are GOING to break, what to do when they do |
||
*** Watch for starting of cracks |
*** Watch for starting of cracks |
||
Line 164: | Line 165: | ||
|| Getting it lit without hurting yourself, getting the flame properly set up for forging |
|| Getting it lit without hurting yourself, getting the flame properly set up for forging |
||
|- |
|- |
||
| Shaping metal || |
|||
| Example || Example || Example |
|||
* Heating to a suitable colour, testing with magnet if you need to |
|||
* Don't touch metal to anvil till you're ready to strike |
|||
** Don't strike the hammers directly on the anvil, they're both hardened |
|||
** Just get the feel of beating on the metal, try both hammers, see what it's like |
|||
* 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 || |
|||
| Example || Example || Example |
|||
* 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 |
|||
|- |
|- |
||
| Shutting down the forge || |
|||
| Example || Example || Example |
|||
* Air off – Gas off – Air on ; for fast cool-down leaving the air running to cool the forge if needed |
|||
* Air off - Gas off with slight delay ; for furnace cooling of metal |
|||
* The forge may stay hot enough to start fires for up to 2 hours |
|||
* Marking out the area of "hot things" when leaving |
|||
|| Safe shut-down when done |
|||
|} |
|} |
||
Normalizing |
|||
Why we need to normalize |
|||
What it does |
|||
Proper procedure |
|||
What happens if we're not hot enough, or too hot! |
|||
Flattening out the rod |
|||
Heating to a suitable colour, testing with magnet if you need to |
|||
Just getting the feel of beating on the metal, try both hammers, see what it's like |
|||
Don't touch metal to anvil till you're ready to strike |
|||
Correct any error immediately, don't let them grow |
|||
Consider the shape we're working towards |
|||
The need to come to both dimensions at once and not over-work in one direction |
|||
We can't fix over-thinning |
|||
REMEMBER TO CORRECT ERRORS AT ONCE |
|||
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 we can do less grinding |
|||
Normalizing |
|||
Repeat the normalization cycle |
|||
Furnace cooling as an option for normalization but not annealing |
|||
Shut down the forge |
|||
Air off – Gas off – Air on |
|||
Leaving the air running to cool the forge if needed |
|||
The forge may stay hot enough to start fires for up to 2 hours |
|||
Marking out the area of "hot things" when leaving |
|||
Normalize and Anneal |
|||
This is the last chance to smooth out any gross surface defects or geometry errors |
|||
Using a little less heat than before as we're not trying to cause bulk movements |
|||
Planishing using the smaller hammers to smooth things as best we can |
|||
Normalize for at least 2 cycles and maybe more |
|||
Fix geometry before cycles |
|||
Using the vermiculite to slow down cooling to achieve maximum softening or furnace cool |
|||
== Shutdown and clean up == |
== Shutdown and clean up == |
Revision as of 05:58, 12 September 2018
Some of the tools at the Hackspace are potentially hazardous to use, for these tools members are required to have an induction before they can use them. Inductions provide the most basic information on how to safely and effectively use the simpler functions of the tools, we appreciate that some members may have professional experience on some of these tools and in this case please tell your induction provider and the induction may be very reduced and just cover any risks or procedures specific to rLab. Some tools have multiple levels of induction in order to cover more advanced uses of that tool without making the basic induction take too long, higher induction levels will introduce some of the more advanced features of the tools but as with all inductions are only intended to provide basic information on the capabilities of the tools and how to use them safely. Some members of rLab may be willing to offer more detailed tuition beyond basic induction level or offer guided practice sessions in exchange for beer money or assistance on their own projects.
For all tools you are only required to take level-1 induction before use, after that you may perform any task that you feel confident you can do safely, higher levels of induction may be useful to you in performing more advanced operations but are not required before doing tasks covered in them so long as you're confident of your ability to handle those tasks without risk to yourself, others, or the tool.
PLEASE NOTE : All induction providers are volunteers who are providing inductions to the best of their ability but are NOT qualified instructors. Inductions are provided on a best-effort basis but you and you alone are responsible for your safety while using the tools and for satisfying yourself that you can operate the tools safely. There are professional training courses available from various providers in Reading and the surrounding area if you feel they are appropriate for the level of work you intend to undertake. Reading these notes is NOT a substitute for an in-person induction.
Note for wiki editors : Please do not edit induction pages unless you are one of of the people that gives that induction
The forge gets up to a maximum of 1350 ºC, uses flammable gas, has the risk of igniting metals and many other hazards, for that reason an induction is compulsory before using the forge. Induction normally takes about 2 hours, and another 2 hours for the forge to cool down afterwards before it can be put safely away. The forge has a useage charge of £3/hr so you can expect to pay in the region of £10 to cover 2 hours of forge time and materials to use for practice.
Safety
Topic | Detailed Contents | Rationale |
---|---|---|
Suitable Clothing |
|
Suitable clothing is essential for safety |
PPE Required |
|
Good PPE to protect from specific hazards |
Workshop hazards and mitigation |
|
Hazards other than fire that could impact the rest of the workshop |
Fire risks |
Fire and burns are the single largest hazard in forging.
|
Things that can cause fire |
Dealing with Fire |
|
Have to be ready to deal with a fire if it happens |
Burn treatment |
|
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]
Topic | Detailed Contents | Rationale |
---|---|---|
States of steel and their properties |
|
Need to know the basics of how steels respond to heat in order to know how to work |
Critical Temperature |
|
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 |
|
Basic ways to change the properties of steels |
Heating Errors |
|
Knowing the serious errors and how to avoid them |
Practical Forging
Topic | Detailed content | Rationale |
---|---|---|
Work Holding |
|
How to hold work in a safe and effective way |
Examining and setting up the Forge |
|
How to get the forge set up and ready to fire safely |
Lighting the Forge |
|
Getting it lit without hurting yourself, getting the flame properly set up for forging |
Shaping metal |
|
Actually moving metal around with the hammers |
Normalize and anneal when done |
|
Post-forging treatments to make usable parts |
Shutting down the forge |
|
Safe shut-down when done |
Shutdown and clean up
Shutting down the forge
As before for shut-down
Letting the forge cool down enough before putting it away
Hand-in-tunnel test
Don’t try to clean inside the tunnel, put it away dirty
Watching out for condensation dripping off the gas bottle
Getting the blades out of the vermiculite and cleaning up.