Practical Welding Exercise 3
Single & multi-run fillet weld deposits ‘t joints’
- Remove from plate surface any rust or scale by wire brushing
- Tack plates together as shown on picture
- Ensure a firm ground / return lead connection at all times
- Ensuring the electrode remains in the joint, touching both plates at all times
- Prepare the electrode as described in Exercise One
- Firstly, deposit the root run using the ‘Oscillation Technique’. For the second pass use the 'Drag Technique' with the change in slope angle as shown. For the third pass use ‘Step-Back Technique’
- All slag and spatter must be removed from the weld deposits and plate surface
- Ensure a firm ground/return lead connection at all times
- Avoid tangling of welding cables and ensure you are not between the cables
- Maintain an eye level view at approximately the same level as the plate
- Weld across yourself, not towards yourself, i.e. stand at 90° to the plate
Repeat as necessary.
Things to Watch Out for: Keeping your lead angle and travel speed within the specified range, and depositing the weld in the correct place. If you keep your lead angles as required, your travel speed will stay pretty much as necessary. As for depositing the weld in the correct place, keep a very close eye on your slope angles and the previous deposit. Practice makes perfect and remember to experiment with current setting.
When welding multipass ‘T’ joints, you may find it useful to change you base current settings, depending upon which pass you are currently welding. Generally, the root pass will require the highest current, the second pass should have the current slightly and the third pass should be somewhere in between the two.
NOTE: Only make the welding machine hot when ready to weld. Ask for the current to be made cold immediately after welding.