Attached video shows the knife in action on 2.5 inch felt coated poly insulation. I've also tried straightening the knife instead of using it like a saw, but that's an alternate method. It takes about 4 passes before it all goes through. This method also leaves a lot of dirt that needs to be removed if the knife gets stuck and tears through the insulation instead of severing it. Foam board and is better than a drywall cutter, but to cut hundreds of foam boards you need another, more efficient method.
XFasten Professional Blue Painters Tape 3/4 Inch x 60 Yards (3-Pack) - Clean Release Wall Trim Tape for Sharp Lines and Residue-Free Artisan Grade Finish
33 Review
AOBEN 750W HVLP Paint Sprayer With 4 Nozzles And 1000Ml Container - Ideal For Home And Outdoor Painting Projects (Blue)
32 Review
STENCILIT® Herringbone Simple Wall Stencil For Painting XL 22X40 In Large Stencil For A Modern Wall Decor Herringbone Wall Stencil For Painting Large Pattern
35 Review
XFasten Blue Painters Tape, Multi-Use, 3/4 Inches X 60 Yards (Pack Of 6) Blue Painters Masking Tape Bulk - Sharp Edge Line Technology, Produces Sharp Lines Residue-Free Wall Trim Tape
31 Review
Varathane 313835 Weathered Wood Accelerator, Quart, Gray
17 Review
SamaN Interior Water Based Wood Stain - Natural Stain For Furniture, Moldings, Wood Paneling & Cabinets (Black TEW-108-12, 12 Oz)
28 Review
SamaN Interior One Step Wood Seal, Stain And Varnish – Oil Based Odorless Dye & Protection For Furniture & Fine Wood (Aged Oak SAM-307, 32 Oz)
9 Review
Upgrade Your Paint Spraying Game With HomeRight'S 27 Oz. Container & Lid For Finish Max Sprayer
9 Review