Tyvek - trimming

Razor blade or the red trimmer works just fine.

Very carefully you can secure the notch on a #12 blade into the distal digit of you dominate hand.
This should allow your index and opposing digits to secure the working end of the blade. As you pass the hand along the securing digits counter-balance align the tip of the razor in the proper elevation and attenuation for an efficient separation of the body and waste.

Or in techno-framer speak... grab the razor blade and hack it off like it was the waste paper it will become. :D
Funny that. My Maxial Facial Surgeon nephew wants to be a framer in his next career. No joke. He's about 25 years aways from retirement, and he already bought my DVD. :D
Oh, that's funny Baer! One just never knows. When I retired from nursing, my supervisor and one of our better physicians asked if they could work for me!

And one better.....true story.....one of our top five respiratory physicians decided to get out of managed care as well and went into Amway! Yep, Amway! I couldn't get over it. Sad....so very sad for the medical community. I hadn't thought about him for ages - should call him up and see what became of his new 'practice'.
The guy I bought the frame shop from was a retired orthopedic surgeon! Thought framing sounded like fun! Bought the biz, went to Larson's school and stuck it out for 6 years. Then decided framing wasn't his "thing" and went back into medicine as a consultant. Good thing for me!