Originally Posted by Terry W
Just curious, does a chunk of spoiler fiberglass break out at the brackets, do the brackets pull out of the roof or do the brackets pull out of the spoiler. i just checked mine and all seems OK.
Just wondering where to keep an eye on.
Originally Posted by gmcgene
Only the center bracket remained attached to the coach when my spoiler came off. All the other brackets were gone. The rivets were all broken off. At least I have the center bracket to use as a pattern to make new ones.
Is riveting the only reasonable method of mounting the spoiler?
Thanks for any new ideas.
The major cause is having the brackets break due to metal fatigue, but it could be argued that loose rivets might play a factor as well.
Once one or more of the brackets weakens by either breaking or losing the rivets, the vibration of the spoiler is amplified, and within a shorter period, other brackets will flex and break and/or more anchoring rivets will work loose. Vicious circle.
The bottom line, however, is the spoiler is lost, eventually, due to broken brackets, but the number of loose rivets on any given lost spoiler has not typically been reported. Replacement rivets like shown below can be used if you are concerned about them pulling out.
Replacement brackets of steel will survive the stress of amplified vibration much better than aluminum, and that seems to be the best solution. Rivets can be replace by screws and nuts on the spoiler itself, but riveting into the rear cap is probably required. If steel is not used due to rust issues, certainly thicker aluminum can replace a bracket. Given the OEM metal, a good, solid aluminum replacement out of heavier gauge stock would be ample.
Note the picture below of a broken bracket. You can see how thin the metal is and how easily the aluminum could break. Note also the rivets in the cap are intact and holding, but the rivets from the spoiler may or may not be, as that part is missing. Still, you can see the partial hole for the spoiler rivet which leads one to think the rivet remained but the bracket tore away.
From that same coach, here is the right side bracket. This was the one that was last to go, apparently, being pulled away by the force of the loose spoiler. The cap rivet has pulled out, but the top of the bracket that connected to the spoiler has broken.
Here is the middle bracket. It is still secure on the cap but the rivets have pulled away from the bracket. Being the middle anchor spot, it is subject to less vibration from wind once the outsides become loose. The metal does not flex as much but the pressure to pull away is extreme.
Bottom line, the bracket are weak due to the metal used and the thickness. Constant vibration from wind pressure can and does initiate a break or increased ability of the entire spoiler to move. That increases the overall stress on all the brackets and, to a degree, the rivets. Overall, the rivets hold until the final collapse. Only when extreme pressure from a departing spoiler is applied will a rivet pull out.
Thanks to Sid & Janet from an early thread for the photos.