I've struggled with this problem for years. It is a segmented plywood
wood or laminated wood garage door that's raised vertically by a
torsion spring. The paint at the bottom of segments (particularly the
next to the bottom one) cracks. The cracks are roughly vertical.
I've repaired this 2-3 times in the past, but it keeps coming back.
I'm fairly sure the problem is that rainwater seeps into the seam
between two segments and runs down the plies. I've tried to seal the
upper edge of the segments with paint but it never stays. When the
door is all the way up or down the segment edges come together (touch)
and the paint sticks to the other edge and is torn/pulled off when the
segments separate while opening/closing. I've tried sealing the edges
with this stuff and injecting it into the paint cracks before
, but it
doesn't seem to do anything at all. I have also injected caulk into
Here are the best pictures I've been able to make to illustrate this
problem, but they don't make it clear.
Note also the bolts that are rusting. I've replaced most of the
rusted bolts over time. I always to seal the bolts from water by
filling the bolt holes liberally with caulk, to the point it squeezes
out in all directions. It helps, but it doesn't prevent rerusting.
If I can't come up with something this time that works I guess I'm
going to have to replace this door that's in good condition otherwise.
Anybody have any new ideas?