## How to Fabricate Trusses for Galvanizing

### Rectangular Tube Trusses

#### Vertical Sections

Hole locations for vertical members should be placed as shown in examples A and B on Figure 3. Each vertical member should have two holes at each end, 180º apart and in line with the horizontal members. It is best if the holes are of equal size, and the combined area of the two holes at either end of the verticals should be at least 30% of the cross-sectional area.

#### Horizontal End Plates

Preferably, the fabrication is completely open. (See example C on Figure 3.)

- If H + W = 24" (61 cm) or larger, the area of the hole (plus clips) should equal 25% of the area of the tube (H x W).
- If H + W = less than 24" (61 cm) but more than 16" (41 cm), the area of the hole (plus clips) should equal 30% of the area of the tube (H x W).
- If H + W = less than 16" (41 cm) but more than 8" (20 cm), the area of the hole (plus clips) should equal 40% of the area of the tube (H x W).
- If H+W = less than 8", leave it open.

### Pipe Trusses 3" (7.6 cm) or larger

#### Vertical Sections

Hole locations for vertical members should be placed as shown in examples A and B on Figure 4.

Each vertical member should have two holes at each end, 180º apart and in line with the horizontal members as indicated by the arrows. It is best if the holes are of equal size, and the combined area of the two holes at either end of the verticals (Areas C and D or Areas E and F) should be at least 30% of the cross-sectional area.

#### Horizontal End Plates

Preferably, the fabrication is completely open with the same hole diameter as the inner diameter of the I tube. (See example G on Figure 4.)

Alternatives would have openings at least 30% of the area of the inside diameter. (See examples H, I, and J on Figure 4.)

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