Is there a difference?

What’s the difference between double-sided tape sold at office supply or art stores, a woodworking tool store or an industrial fas­tener supplier? In practical terms, not as much as I imagined. If the work surfaces being bonded are clean and dry, and we use enough tape to hold firmly, they all work quite well.

To answer my question, I examined “woodworking tapes” from PSI and XFasten, an “industrial tape” from 3M, and an “office/arts tape” by Scotch. I compared their width and length, film thick­ness and material, stickiness and bond ability, ease of application and lastly, ease of removal and residue, all important factors to woodworkers.

All but one came in rolls of 108 ft. (36 yds.) with widths of either 3/4″ or 1″, though 3M 9579 is available in widths from 1/2″ to 2″ and even wider. Scotch Poster Tape only comes in a dispenser roll of 3/4″ × 4.16 yds.
The adhesive film layer thickness, material and adhesive vary from brand to brand. PSI Woodworking Tape is a sticky (my term for comparison here) opaque paper with a thickness of 0.15mm (my measure by digital Vernier gauge) with a slick crepe paper liner. XFasten has a gooey-tacky (again, my description) adhesive on an opaque woven gauze and is the thickest at 0.25mm, backed by a plasticized paper liner. The industrial 3M 9579 tape employs a “quick stick” (3M’s term) adhesive on an opaque polyethylene film measuring 0.18mm by my gauge, lined by plasticized craft paper. Lastly, the Scotch Poster Tape, a tad less sticky than the others, uses a translucent plastic film of 0.12mm thickness overall, lined by a durable plasticized paper.

All of the tapes I sampled were very user-friendly, peeled off the roll readily, cut crisply (XFasten was a tad more resistive because of its base layer), each tearing to rough length with little effort. Peeling the backer off the film went easily with each tape, though the thin, clear film and thicker backer of the Scotch Poster Tape required a bit more concentration.

Each of the tapes offer excellent adhesion. To test this I bonded a 1-7/8″ × 10″ strip of freshly planed maple to a strip of freshly cut Baltic birch plywood, covering each joint generously just as I’d bond a blank to a template or jig for shaping. I then pressed each strip down equally firmly and left them a while to see if time would reveal any ugly surprises when I separated the parts. After three hours, I pried the maple from the plywood starting at one end using only a 2″ chisel tip, merely for leverage. Each took moderate effort to start, then offered some resistance when I peeled the maple away from the plywood, but each parted cleanly. The Scotch product showed only slightly less adhesion, as might be expected given its intended purpose.

As for residue and/or grain lifting, none showed any trace of these downsides. In each case, because the planed hardwood had a smoother surface than the sanded plywood, the adhesive remained stuck to the maple but peeled away cleanly with surprisingly little effort.

Pricing remains the biggest difference among this selection of samples with the 3M 9579 and PSI examples selling for approx­imately $20 per 36 yd. roll ($0.56 per yd.); the Scotch Poster Tape at $12.49 per 4.16 yd. roll ($3 per yd.); and finally XFasten Woodworkers Tape in a three-roll pack (36 yds. per roll, totalling 108 yds.) at under $30 per package ($0.28 per yd.).

All said, for a firm, reliable, user-friendly bond for a host of wood shop applications, my first choices would be 3M 9579 and PSI Woodworking Tape. For value per yard the XFasten Woodworkers Tape gets the nod while the Scotch Poster Tape punches above its weight in low-impact applications and may be the most easily accessed in a pinch.

In summary, with clean, smooth surfaces and sufficient coverage to bond the parts, but not get cut away during the shaping operation, double-sided tape may allow you to replace hot-melt glue or obstructive clamp­ing very safely. It’s a great tool to add to your tricks bag.