McClain Trailers fields a lot of questions: - Why doesn't  McClain Trailers weld their cross members onto the I-Beams?  Below is a good example why McClain has chosen to bolt their cross member onto the I-Beam.  Another reason bolting the cross members onto the I-Beam allows us to get the boat lower. 

Aluminum trailer have to be able to flex.  Welding the cross member onto the I-Beams prevents their capability to flex thus causing the I-beam to crack because of stress.

The heating of the aluminum through welding creates a lot of localized heat and also sets up internal stresses that can lead to cracks in the future. (See pictures below, all taken from the same trailer in McClain's 12945 I-10 East repair facility.)

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Welded Verses Bolting Aluminum Trailer

 

Click on Picture for a more detail view