I tried the hot knife on 3d parts, I did not love the results, but it could have been the cheapo "hot" knife I tried. I have had MUCH better results with a fresh blade and by warming the sprue/plane up in very hot (but not boiling) water for 5 mins or so before attempting to cut or snip the attachments. hot tap-water microwaved for about 2 minutes and then kept in an insulated mug with the parts soaking in it is the way I'll be going from here on. I've never had an issue with orange hobby or 3d wild parts, the l'arsenal planes are by far the worst 3d planes I have ever dealt with.