Knowledge Center
Hot Start
Hot Start in Welding
Hot Start is an advanced feature in modern welding machines that temporarily increases the welding current during arc ignition. This momentary boost in amperage helps establish a stable arc quickly and efficiently, particularly when working with challenging materials or in difficult conditions.$CITE_1
What is Hot Start?
Hot Start is a specialized function in stick welding (MMA/SMAW) power sources that delivers a controlled surge of current at the moment of arc initiation. This temporary increase in amperage—typically 30-50% above the set welding current—helps overcome the initial resistance when striking an arc on cold metal.$CITE_1
Key Characteristics:
- Operates only during arc initiation (first 0.1-0.5 seconds)$CITE_2
- Provides a temporary boost in welding current
- Automatically returns to normal welding parameters after ignition
- Adjustable on most modern welding machines
- Particularly valuable for difficult-to-start electrodes$CITE_3
Current Boost Pattern
Hot Start delivers a precise, momentary increase in current that quickly establishes the arc before returning to the set welding parameters$CITE_1
Benefits and Advantages
Hot Start technology offers numerous benefits that significantly improve welding performance, particularly during the critical arc initiation phase. Understanding these advantages helps welders leverage this feature effectively across various applications.$CITE_2
Prevents Sticking
By delivering extra power at the moment of contact, Hot Start significantly reduces the likelihood of the electrode sticking to the workpiece during arc initiation.$CITE_1
Improves Ignition
The temporary current boost creates a larger, more stable initial weld pool, making arc starts more consistent and reliable even in challenging conditions.$CITE_2
Overcomes Cold Material
The additional heat input helps overcome the thermal sink effect of cold base materials, especially when working with thick sections or highly conductive metals.$CITE_4
Technical Insight:
Hot Start functions by monitoring the initial contact between the electrode and workpiece. When this contact is detected, the power source rapidly increases the current output according to the Hot Start settings, creating stronger heating at the point of contact. This additional energy helps form a molten pool more quickly, facilitating smooth arc establishment.$CITE_1
Additional Benefits
- Reduces the need for repeated arc striking attempts
- Minimizes the formation of inclusions from failed starts
- Improves productivity by reducing start-related downtime
- Enhances weld quality at the beginning of each weld pass$CITE_2
- Particularly helpful for welders with less experience$CITE_3
Applications and Settings
Hot Start is particularly valuable in specific welding scenarios and with certain electrode types. Understanding when and how to adjust Hot Start settings can significantly improve welding outcomes across various applications.$CITE_2
Cellulosic Electrodes
When working with cellulosic electrodes (E6010, E6011), which can be difficult to start, a higher Hot Start setting (70-100%) is typically recommended. These electrodes benefit significantly from the additional current during ignition due to their deep-penetrating characteristics.$CITE_1
Basic Electrodes
For basic low-hydrogen electrodes (E7018), which often require pre-heating and can be challenging to start, a medium to high Hot Start setting (50-80%) helps establish a stable arc without sticking.$CITE_2
Rutile Electrodes
General-purpose rutile electrodes (E6013) typically start more easily and may require only a low to medium Hot Start setting (30-50%) to achieve optimal results without excessive spatter.$CITE_3
| Application | Recommended Hot Start | Benefits |
|---|---|---|
| Cold Weather Welding | High (70-100%) | Overcomes increased material resistance and reduced electrode performance$CITE_4 |
| Thick Materials | Medium-High (60-90%) | Compensates for heat sink effect of thick sections$CITE_2 |
| Rusty or Contaminated Surfaces | High (70-100%) | Helps burn through surface contaminants during ignition$CITE_1 |
| Thin Materials | Low (20-40%) | Prevents burn-through while still ensuring reliable starts$CITE_3 |
Intensity
Controls the percentage increase in current during ignition$CITE_1
Duration
Determines how long the increased current is applied$CITE_2
Response Curve
Defines how quickly current rises and falls$CITE_3