ORIGINAL: SeamusG
Ultracote changes its ''cuttable'' character. If you use a low temp trim iron to tack and seal an edge, it is very easy to cut. However, if you turn up the heat (270 or so) then the adhesive gets involved and makes it like chewing shoe leather. For a top quality edge it's best to use a new blade or frequently stropping the edge to keep it from ''laying over'' and appearing dull. Don't use a blade that has been used to cut material during the contruction phase of the build!
That lines up with my observations. I was using ultracote, so when I tried to follow up and trim the excess; the glue would interfere with the cut exactly as you said. I have an adjustable trim iron. I will turn the heat down and see to produces better results.