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First shot at MMA induction text
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== MIG Welder induction - Level 1 ==
Level 1 induction in intended to cover the basics of how to use the [[Tools/EMP235ic|MIG welder]]. It should cover basic safety information and how to use the welder effectively on mild steel in positions 1G and 2G/F. People undertaking MIG induction need to have overalls or other non-flammable clothing that covers all exposed skin except for head and hands, clothes are likely to get burn spots on them. Wear stout shoes or boots, no open shoes allowed. If you have any metal you'd like to practice on then please bring it with you so long as it's plain steel with no galvanised coating or paint but if you don't have any then we usually have suitable scrap around to practice on. There's no charge specifically for the induction but normal welder usage charges apply, you should expect it to cost around £5 for the induction and a bit more if you spend some time
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* Check metals are suitable
** Mild steel only at level 1
** Beware of
** Beware of lead-bearing and copper-bearing paints
* General angle grinder safety
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* Clean up weld area - be aware of burning paint
* Clean area for earth clamp
*
** No bevel on thin materials
** Regular 2/3rds bevel most of the time
**
|| Proper preparation is necessary for good welds, cover bevel patterns for other weld types later
|-
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== MMA (Stick welding) Induction ==
This induction in intended to cover the basics of how to use the MIG welder in MMA (stick welding) mode, it covers basic safety information and how to use the welder effectively on mild steel in positions 1G and 2G/F. It is strongly recommended that people undertake MIG induction and practice it thoroughly before attempting stick welding, that said you can start welding straight away with stick but it's likely to take considerably longer to develop the required skill to use it effectively. People undertaking stick welding induction need to have overalls or other non-flammable clothing that covers all exposed skin except for head and hands. Wear stout shoes or boots, no open shoes allowed. If you have any metal you'd like to practice on then please bring it with you so long as it's plain steel with no galvanized coating or paint but if you don't have any then we usually have suitable scrap around to practice on. There is a charge of £10 for the induction to cover materials and a bit more if you spend some time practicing afterwards which is strongly recommended. The needed materials are usually kept in stock but if we've run out it will take several days to get more. This induction is estimated to take 1-2 hours.
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! Topic !! Detailed contents !! Rationale
|-
| Types of welding available ||
* MMA - Fast, thick, dirty, good outdoors, medium-high skilled
* MIG - Fast, medium thickness, relatively clean, low-skill requirement
* TIG - Slow, Neat, special materials, super-clean, high-skilled
* Gas - Most similar to TIG but for safety reasons we won't be doing this at rLab
* Forge - V.V.Slow, good for big flat welds, high-skilled
* Spot - Tiny spot welds for joining plate, low-skilled
|| Which technique to use for which weld
|-
| How it works ||
* Machine strikes an arc between the work and a consumable electrode, melting a pool of metal
* The electrode melts and is propelled by the arc across the gap into the pool
* The flux coating on the rod breaks down, emitting inert gas to protect the weld from air and forming a coating of slag over the hot metal to further shield it
* Earth clamp provides return path
|| Basic process details
|-
| Safety ||
* Fire hazard
** Metal sparks and radiant heat/light
** Clear area of flammable materials, be aware of solvents and vapors
** Having fire extinguishers handy and what types are suitable
* Arc-eye hazard to you and people around you
** Using an auto-darkening welding mask
** Suitable settings on mask (9-11, 12 maybe - start at 10 and adjust)
** Shouting "Eyes" if there are other people around
* PPE - Overalls, stout shoes, thick leather gloves, mask, dust protection when needed, Cover all exposed skin or you'll regret it!
* Care with Galvanized steel, risk of metal-fume-fever
*Gas safety
** Enclosed spaces, the gasses produced during welding are irritant and asphyxiant.
** Fumes are nasty, use dust masks or respirators
* Electrical Safety
** The voltage is low, but you still don't want to touch it
** Mind where you put the rod, it's always live and will arc to anything earthed, eject the rod when putting down the stinger
** Power is controlled from the base unit
** NO RINGS, NO WATCHES!!
** Users with implanted medical devices should seek doctor's approval before welding, it's not usually a problem, but please do check
** The welder plugs into a 16A socket, there is a 16A trailing socket on the pillar, it's fed from the bandsaw power point
** If the bandsaw is used at the same time it may trip the breaker
** Use only suitably rated industrial extension leads, they're in the desk drawer B1B
** Extension leads are a trip hazard, warn people
** If something does go wrong, shut off power before anything else
|| Using the equipment without harming self or others
|-
| Preparing to weld ||
* Check metals are suitable
** Mild steel only at level 1, Stainless, tools steels and aluminium are possible but we're not covering them today.
** Beware of galvanized steel
** Beware of lead-bearing and copper-bearing paints
* Check the rods are suitable for the material. There are a wide variety of rods available
** 6013 are a common type and considered "universal" they have a heavy flux and cut through grease and dirt well
** 7018 Are more common in america, give a stronger weld but have less flux so they need cleaner material
** There are dozens of other types, if in doubt check online recommendations
** Make sure the electrode size is suitable for the work
** Rods must be kept dry, all rods are moisture sensitive but some more so than others
** Baking rods if they're not brand new
** Keeping them in a rod oven if you get serious about MMA welding.
* General angle grinder safety
** Types of disc
** Inspecting grinder and disc
** Changing the disc
** Care of position and cut angle
** Dust protection, eye protection, gloves
** DO NOT TWIST in a cut
* Clean up weld area, a bit, Stick welding can tolerate more dirt and contamination than any other type of welding
* Clean area for earth clamp
* Beveling edges to form a path for the bead on butt joints
** No bevel on thin materials
** Regular 2/3rds bevel most of the time
** Beveling from both sides for very thick
|| Proper preparation is necessary for good welds, cover bevel patterns for other weld types later
|-
| Machine Description ||
* Parts
** Base unit is a constant current power source capable of currents between 15A and 240A and an open-circuit voltage of 50V
** Stinger provides a way to hold the electrode, it can be held in various positions but must always be well-seated into the clamp
** Earth Clamp
|| Covering what all the parts are called and setting current
|-
| How to actually execute a weld ||
* Normal welder settings
** Navigating the menus and selecting MMA mode
** Setting suitable current for the electrode size
* Proper position of self and electrode, direction of motion
** Suitable angles to work at (45 degrees is common but much more sometimes helps)
** Vertical and overhead welds are things that can happen, but not covered at level-1
* Correct distance (close! almost touching, sometimes actually touching)
* Tapping flux off the tip if needed to get a clean strike
* Proper posture for welding
** Getting comfortable
** Supporting the cable if needed
** Chairs if they help
** Being comfortable and able to move without stretching is critical for good welds
** Resting your other hand on something to use as a guide
* Scratch striking, Striking off the work and moving onto it
* How the pool forms
* Moving the pool along
* Keeping the electrode at the nose of the pool
** Further towards the tip of the pool = fast move, thinner bead, less penetration
** Further towards the back of the pool = slower movement, wide bead, deep penetration
** This is your primary method of regulating the travel speed, change you aim point and the rate the bead moves across the work will change
* Moving patterns, circles, arc, steady
* You may need to adjust the shade of your mask to get a clear view
** Each shade number upwards cuts the light you see in half
** The temptation will be to look at the arc, but try to focus on the puddle. The puddle is what you need to control and let the machine take care of the arc.
** Letting weld cool from red heat then chipping off slag. Goggles while chipping. Can sometimes restart through still hot slag, but never through cold slag.
[Demonstrate a good simple weld bead]
|| Cover the basic technique of establishing and moving a weld bead
|-
| Problems ||
[Deliberately set up and demonstrate each of these faults]
<need to work on this>
|| Recognizing faults and knowing how to fix them
|-
| Practicing a steady bead || Inductee practices laying down a straight and steady, well-fused bead on flat stock till competent || Getting the basics right
|-
| Butt joints ||
* Proper grinding and prep
** Bevels right way up and properly spaced
** Proper fit-up between parts
** Option of using backing blocks (Always permanent for MMA)
* Using holding magnets and clamps
* Do NOT tack work to the table
* Tacking to limit distortion, you are GOING to get distortion
** Straight, back-track and half-split tack welding
** But don't make the weld sections too short, stopping and starting introduce chance of inclusions
* Root-weld and multi-pass welding on thick material
[Demonstration and practice till successful]
|| Executing the most basic weld
|-
| Fillet joints ||
* Don't need to grind, but parts need to be clean
* Good fit-up important, will makes things much easier for you
* Proper position and angles
** Push angle a little steeper than normal
** Biased towards the vertical plate
** Weaving pattern, spending more time on upper plate
* Stitch and alternating stitch to control distortion
* Pre-compensation for distortion
[Demonstration and practice till successful]
|| Second most common weld type
|-
| Lap joint ||
* Lack of need for grinding but must still be cleaned
* Treat is as two fillet joints
** But watch out for heat buildup in the edges
** Extra care if the sheet is thin to watch for balling up
* Alternating stitch welds to control distortion
|| Next joint type
|-
| Shutting down and cleaning up ||
* MMA welds will always require cleaning with the chipping hammer and wire brush at a minimum
** Wire brush if you don't care about cosmetics
** Flap discs will tidy up welds that are good to start with
** Grinding discs will remove messy welds quickly
* When you're done shut off the power to the welder and putting the leads away
* Sweeping up and putting everything back where it belongs
* Discuss any projects the inductee is working on to provide pointers
|| Clean up after yourself and pay what you owe!
|-
| Final thoughts ||
* This has only been an extremely brief over-view of Stick welding
* Do not expect your joints to be structurally sound or pretty until you have practiced for many hours
* If you want to weld aluminium or magnesium alloys, Stainless Steel, Brazing or other techniques then you can look at [[Tools/TIG/induction#level2|TIG level 2]] or [[tools/mig/induction#level2|MIG level-2]] inductions although it's not compulsory to do level-2 inductions if you've already done the relevant level-1 inductions and if you think you can manage these techniques without further help
* If you want further tuition then some members of rLab are willing to provide this, but they may charge for it.
|| Closing comments
|}
[[category:inductions]]
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