nathan_thompson62•1mo agoProlific Poster

An old guy in a Denver supply house showed me a seam trick from the 70s

I was picking up some seam tape and he saw my knife. He said, 'Back then we used to heat the blade a little with a lighter before cutting the backing on a hot seam.' We stood by the adhesive aisle for ten minutes while he explained how the warm metal would seal the synthetic fibers as you cut. I tried it on a job the next week and it worked perfectly on that old nylon. Anyone still use that trick or have other old school fixes?

2 comments

2 Comments

spencerw721mo agoMost Upvoted

Sounds like a good way to burn yourself or start a fire for no real gain. Modern seam tape adhesives and synthetics are totally different than the 70s stuff. That trick probably only worked on a specific old material and a warm blade could easily melt or warp the tape backing now. Just use a sharp blade and proper technique.

tylerbutler1mo ago

I read an article last year that tested heated blades on modern tent fabrics. Spencerw72 is right, the test showed clear melting on synthetic tape edges. That old trick seems risky with today's materials.