Dylan,

Any tips you (or anyone else) can share on getting successful results
with this type of "hot air plastic welding" product?

I bought one from Harbour Freight and tried to use it to repair a broken
Thule roof box that I was given.  I got terrible results. Granted, it
was my first attempt at using the thing and there were minimal
instructions.   Maybe it won't work on this type of plastic.

The heat made the edges of the crack in box start to curl up and widen
faster than the rod would melt and put new material into the crack.  I
gave up after figuring out that I was making things worse.

The remainder of the post is just about how I fixed the Thule box in a
very crude though successful way and where I got the broken box - feel
free to ignore this.

Some white epoxy like material (a 2 part mix kit) was used on a crack on
the bottom of the box where the fasteners go in with some success.  I
had to do some sanding and grinding both inside and out so that the
attachment hardware would fit in place.

I finally fixed the remainder of the damage to box, a long crack on the
left side of the top, with some sort of plastic "epoxy" 2 part kit -
mine was black - that I got at Advanced Auto.  It was for sale in the
area with body repair, paint, sanding materials, not with the gasket
sealers / makers, JIB Weld, etc. type products where most of the quick
bonding epoxy products like the first one I used were located.  I also
put a layer of fiberglass on the inside under the one long crack that I
sealed with this stuff.   I got a decent water proof fix that has
withstood torrential rains at both highway speeds and sitting.  It
doesn't look great but it works just fine.

Relevant list(s) history:  This box was on Larry Chase's first Westy /
Roadhaus - an 85 (?) 2WD.  According to Karl Mullendore, Larry misjudged
his needed clearance and hit something with it, causing the damage.
Karl ended up with the box and the Yakima bars and also had the first
Roadhaus, which he fixed it up some before selling it.  A couple of
years ago he offered the bars for a cheap price and the broken box for
free to the list if someone who would come pick them up at his shop in
Gapland, MD, which isn't that far from Baltimore.  So, I snagged them
and eventually fixed the box early this past summer.  Then I got some
necessary adapters from a Syncro list member's "garage" sale and I was
ready.  They have been to UT / CO and back and on several astronomy
related camping ventures into the WV mountains.

Sam

--
Sam Walters

Baltimore, MD