Hot knife for ultralight fabrics: your recommendation?

I use a roller cutter.

I used a standard pencil-style soldering iron with a round point, and that worked fine for me as long as I pulled it along the straight edge at the right speed. Too slow, and it does indeed start to melt in ways that are unwanted, too fast, and it doesn’t melt cleanly through. Mine is a Weller, but any low-wattage iron should work. It even cuts through 420 Robic just fine. I’ve seen people rig up an exacto blade to them, but I found it unnecessary.

Thank you, Michael. I’ve gotten hold of a pencil-styled soldering iron and it seems to work fairly well.

I use a Weller with a custom ‘knife blade’ at the tip. It works fine on silnylon, even quite heavy stuff.

Cheers

Thanks, Roger. Sounds like that’s the consensus.

I have one of these and it works quite well.

https://www.amazon.com/gp/product/B01N0KF6SR/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

I should add: I have a large sheet of old cheap thin 3-ply which I cut onto. It has many burn lines. Better that than the floor!

Cheers

When I was making tents in the 1970s I also used a pencil tip soldering iron.  Worked well.

I used it on a large aluminun sheet (4’x8′?)  Big sheets of this were commonly available at surplus yards in Seattle in the 1970s.  Might have been a result of the airplane industry at the time.

WINONS Hot Knife

I have the same one Joe G linked to above. It’s worked great on anything from silnylon to DCF to X-Pac to 1000D cordura and webbing. Seems nearly identical to the more expensive one that Sailrite sells. I’ve used them both and couldn’t tell the difference.