|
Yes, just like pressing a guitar string down on the 12th fret you suppress the fundamental mode of vibration and only allow the 2nd and higher modes. I filled in the gap between the supporting rib and the bottom of the hood skin with a clear sealer which remains flexible (took a while to dry). The flexibility has the double advantage of introducing a small amount of viscoelastic dampening. Constraining the hood in the center has effectively eliminated the fundamental mode of vibration across the width of the hood; but, now on occasion I get 2nd mode vibrations - vibration peaks that occur 1/2 way between the outside edge of the hood and the center rib. The displacement of these vibrations is much smaller and only occurs briefly when accelerating. I probably would not have noticed them if I weren't looking for them.
I had previously made the comment that the gap between my hood skin and the rib was small. I don't know what planet I was on when I made that observation as the gap between the rib and the hood skin was more like 1/4" in the center of the rib. I debated whether I should press the hood down so that it was in contact along the length of the hood while the adhesive set (essentially eliminating the gap). Because the hood profile seemed to be correct with the gap I elected not to do this and just filled the gap with sealant and allowed it to set.
|
