TIG welder

Miller Dialarc HF
TIG (Tungsten Inert Gas) welding is particularly useful for aluminium, It uses an electrode nozzle with a fixed (should be permanent, but they do wear) tungsten tip where a plasma 'flame' is created (started with a high-voltage / high freequency starter) and used to heat the filler wire and joint. The nozzle allows a flow of inert shield gas around the working area, reducing slag creation and (particularly important with aluminium) oxidation.

The TIG welder is a 'stick' welder - the electrode / nozzle is held in one hand, and the filler wire applied with the other.

Shield gas

For the TIG we use a Pureshield Argon.

Capacity and rating

The Tig welder has a large range

Controls

Details on the front panel controls

Name	Picture	Description
Main On Off Switch		Main switch on the welder, remember to turn off the welder as much as possible in-between setting up for welds
DC+ AC DC- selector		Do not change this setting with the main power switch ON. This selector has three positions that control the mode of the welder DC- (DCEN), DC Electrode Negative, used for Steel TIG AC, used for Aluminium TIG DC+ (DCEP), DC Electrode Positive, used for Arc
Working power range selector		Do not change this setting with the main power switch ON. There are three possible working ranges, low, medium and high. Each has a slightly different range for DC or AC Position AC DC Up 140-310 125-310 Middle 40-165 40-190 Down 10-45 10-55
Percentage power dial		Main power control dial, used to fine tune the amp control of the welder. This dial acts as a percentage of the current selected range.
Remote control enable		Used to enable remote current control when a foot control is installed. Until we have a remote foot pedal this should be left in the OFF position.
High Frequency control		Controls the high frequency generation of the welder, this switch has three positions and each has a set use. Up (IO) High frequency start, use this for DC TIG welding (Steels) Middle (O) Off used for Stick welding Down (I) On, used to AC TIG welding (Aluminum)
Remote trigger enable		This should be left in the ON position. Used to enable the remote trigger, only place in OFF position when doing Arc welding
Gas overrun timer		Controls how long after arc cut off the gas will run for. Outer scale is tungsten width, inner scale is time in seconds

Tungsten and collets

We have a selection of the following tungsten tips and collets to fit

Size	Color band	Grade	Used for	Notes
1.6mm	Red	2% Thoriated	DCEN Steel	Slightly radioactive! Do not sharpen without wearing a dust mask.
2.4mm	Red	2% Thoriated	DCEN Steel	Slightly radioactive! Do not sharpen without wearing a dust mask.
1.6mm	White	Zirconaited	AC Aluminium
2.4mm	White	Zirconaited	AC Aluminium
1.6mm	Gold	1.5% Lanthanated	AC or DCEN, All rounder Steel or Aluminium
2.4mm	Gold	1.5% Lanthanated	AC or DCEN, All rounded Steel or Aluminium

Tungstens come in a a range of different grades/types, each performs differently and have their own uses.
They are marked with a colour band at one end, do not grind this off!
The following was borrowed from here

ZIRCONIATED Tungsten Color Code WHITE or BROWN, are best suited for AC Tig welding applications.
Zirconiated, White, AC Welding applications. Better start up than Pure Tungsten, Balls up well and has a more stable arc than Pure Tungsten. Better current carrying capacity and high resistance to contamination during welding.

LANTHANATED Tungsten Color Code BLACK, GOLD or BLUE, is suitable for AC & DC welding applications.
Lanthanated, Black, AWS Class EWLA-1.5, AC & DC welding applications. Non-Radioactive Good arc characteristics in ac/dc applications. Applications: carbon & stainless steel, nickel alloys and titanium.

CERIATED Tungsten Color Code GREY or ORANGE, are best suited for low amperage DC welding applications.
Ceriated, Grey, An excellent alternative to Thoriated tungsten especially in low amperage welding. Takes 10% less current to start and has a very stable arc.

PURE Tungsten Color Coded GREEN, are best suited for AC Tig welding applications.
Pure Tungsten, Green, AWS Class EWP, AC welding applications. Least expensive of all electrodes. Applications: aluminum and magnesium alloys.

THORIATED Tungsten Color Code RED, YELLOW, MAUVE or ORANGE, is best suited for DC Tig welding applications.
2% Thoriated, Red, AWS Class EWTH-2, DC welding applications. The most common type of electrode used today. Applications: carbon & stainless steel, nickel alloys and titanium.

Grinding tip shapes

Do not grind the end with the color band!

Filler rods

We have the following stock of filler rods

• Steel
• Stainless steel
• Aluminium
• Copper

Power supply

A 63A plug and socket connection is used, with a pushbutton on/off control station and no-volt release.
RFID control of access will be installed shortly.

Tig welding tips

Random collection of useful links

• http://www.mig-welding.co.uk/tig-technique.htm
• http://www.millerwelds.com/resources/improving-your-skills/tig/
• http://www.mig-welding.co.uk/tig-calculator.htm
• http://www.gowelding.org/TIG_Welding.html