crazy band saw blade question!

[mggraphix]

I had to make a few cuts the other day with the handheld bandsaw while on the job. The temp was about 20-30 degrees fahrenheit. I had the saw in the cab of the truck. Same saw I just made about 25 cuts with in the shop. (standard carbon flat bar) After removing the saw from the cab the first 2 or 3 cuts were fine then the saw sat for about 45 minutes outside. On my next cut after the saw was idle for the 45 minutes it would barely scratch the same flat that just cut like butter 45 minutes earlier. I installed my spare (new) blade that was also sitting in the box outside for the duration and it did the same thing. Barely scratching the surface. I couldn't get 1/16 depth cut. I tried different pieces that I had on the job also. I ended up using a hacksaw that was also in the cab. I was cutting at the same speed I always do. I know the blade should have had much more life to it. Came back to the shop put an old blade in it and it cut the same piece fine. I haven't left it out in the cold again to test any theory's. I have no idea why the cold would have had an effect on the blade. I am stumped here. The blades were Milwaukee 14 tpi.
Any insight will be greatly appreciated.
Thanks
Gene

[Careless]

When saws are cold, the tension on the blade is a lot less tight, and you probably experienced blade dragging, which would scratch the surface of the material, and not cut it.

You need to adjust the tension to a temporarily tighter setting if it's possible on your saw. If not, put a pylon next to the saw (if on-site) and let it run on it's own to heat up the rolling mechanism/bearings until it comes up to proper tension.

This way the blade won't drag. Also, a little propane to perform a localized whisk over the material itself might allow it to cut a little easier depending on what it is.