Mister Science rides again. I’ve been doing some fit punching on my new pair of Dynafit ZZero. Master bootfitter Mark Rolfes does this by feel and it seems to turn out pretty good, but he does find the Pebax plastic to be trickier than the usual polyurethane of most boots. Since I’ll be doing some of the punching myself, I figured using my trusty infrared thermometer could prevent me from over-heating and thus ruining a pair of expensive boots.
I did some web research and found that Pebax plastic is supplied in different varieties with different melt temperatures. Since I don’t know what variety Dynafit uses for their ski boots, some direct observation was in order. (See menus above for our Glossary, which has more info about Pebax.)
Above are buckle straps from my older pair of ZZero. Top one in photo was malleable at 200 degrees F, while the bottom one melted at around 300 degrees F. I’ll experiment more today while punching the actual boots, and report back, but it appears that the safe temperature for Dynafit Pebax boot punching is probably just over 200 F.
Another thing I discovered was that my variable temperature heat gun is useful, but the temperatures shown on the settings buttons are way off from what the gun outputs. So, thermometer required.
Know there are different types of Pebax with different optimal molding temperatures. Check this out for info.