There are 3 points very important to truss:
1. Materials
6082-T6 aluminum is better than 6061-T6 in toughness and loading. It usually bend slowly when out of loading. And it is enough time to away from the structure.
2. Thickness
Thickness is a part that depend on the truss strength. There are 2mm, 3mm, 4mm 5mm. What kind is used more is 3mm, because it is suitable for 8~18m span structure and light.
3. Welding
As we know, welding balance depend a truss quality. We always use import rod because of its materials. Easy compare which is good one.