04-23-2019, 06:09 PM
I’ve been working non a frame-and-panel back for the Federal slant top desk I’m building. I’ve completed the frame and glued it up, except for the two end stiles that will be glued on after the panels are inserted.
IMG_4462 by Hank Knight, on Flickr
I resawed some 4/4 white pine I’ve had for a long time for the panels. The panels are 18” wide, so I need to glue up some narrow pieces of the resawed pine to get the width I need. I’ve struggled with gluing up thin panels in the past until I learned a luthier’s trick that makes the whole process a snap. I thought I’d post it here for those of you who may not know it.
3M makes a painter’s tape specifically designed for pinstriping automobiles. It’s similar to the blue painter’s tape we’re all used to except it has a lot more stretch to facilitate taping smoothly over the curves of an auto body. It’s light green color and 3M calls it “Scotch 233+”. I’ve seen painter’s tape the same green color at the BORG, but it’s not Scotch and I’m not sure if it has the same stretch quality, which is key to this process.
After resewing the panels and planing them to the desired thickness (a little shy of 3/8” in this case), I book matched them, folded them together and planed the mating edges. This gives me a perfectly mated joint even if I’m off 90 degrees a little. It usually takes me several tries before I get a perfectly mated joint the entire length. Once I’ve accomplished that, I lay the panels on a flat surface and butt the joint together. Then I apply strips of the green painters tape, about 3” apart at 90 across the joint. Here’s the trick: while applying the strips I stretch the tape as I lay it down. When I release the tension, the tape relaxes and pulls the joint together.
IMG_4455 by Hank Knight, on Flickr
When I’ve applied all the strips to one side, I apply a second strip of painters tape down the length of the joint. This helps keep the pieces aligned during the remainder of the procedure and reduces squeeze out on the back side.
IMG_4457 by Hank Knight, on Flickr
I apply VERY THIN line of glue on each edge, open the panels up flat and place them, face down, on a flat surface. Then I repeat the application of painters tape strips on the back side, stretching the tape as I apply it.
IMG_4458 by Hank Knight, on Flickr
Once done, I have painters tape on both sides of the panel that is pulling the joint together with enough force to produce a little squeeze out.
IMG_4461 by Hank Knight, on Flickr
This is why I don’t want a heavy glue application – a light glue application is sufficient to secure the joint and it avoids a big, messy clean up. When the taping is done, I place a couple of flat boards on the panel and add a heavy weight to keep the panel flat while the glue cures.
IMG_4460 by Hank Knight, on Flickr
I can handle it after about an hour, but I’m going to let this sit overnight before I cut the panels to final size and install them in the frame.
I’ve used rub joints for thin panels and clamping jigs with wedges. These both work (except maybe the rub joints), but this stretchy tape method is simple, requires no fancy jigs or equipment and it works every time. I’ve used it on thicker panels, but I prefer clamps for anything over about 1/2”. This is my preferred method for thiner stock.
Hope you find this helpful.
Hank
IMG_4462 by Hank Knight, on Flickr
I resawed some 4/4 white pine I’ve had for a long time for the panels. The panels are 18” wide, so I need to glue up some narrow pieces of the resawed pine to get the width I need. I’ve struggled with gluing up thin panels in the past until I learned a luthier’s trick that makes the whole process a snap. I thought I’d post it here for those of you who may not know it.
3M makes a painter’s tape specifically designed for pinstriping automobiles. It’s similar to the blue painter’s tape we’re all used to except it has a lot more stretch to facilitate taping smoothly over the curves of an auto body. It’s light green color and 3M calls it “Scotch 233+”. I’ve seen painter’s tape the same green color at the BORG, but it’s not Scotch and I’m not sure if it has the same stretch quality, which is key to this process.
After resewing the panels and planing them to the desired thickness (a little shy of 3/8” in this case), I book matched them, folded them together and planed the mating edges. This gives me a perfectly mated joint even if I’m off 90 degrees a little. It usually takes me several tries before I get a perfectly mated joint the entire length. Once I’ve accomplished that, I lay the panels on a flat surface and butt the joint together. Then I apply strips of the green painters tape, about 3” apart at 90 across the joint. Here’s the trick: while applying the strips I stretch the tape as I lay it down. When I release the tension, the tape relaxes and pulls the joint together.
IMG_4455 by Hank Knight, on Flickr
When I’ve applied all the strips to one side, I apply a second strip of painters tape down the length of the joint. This helps keep the pieces aligned during the remainder of the procedure and reduces squeeze out on the back side.
IMG_4457 by Hank Knight, on Flickr
I apply VERY THIN line of glue on each edge, open the panels up flat and place them, face down, on a flat surface. Then I repeat the application of painters tape strips on the back side, stretching the tape as I apply it.
IMG_4458 by Hank Knight, on Flickr
Once done, I have painters tape on both sides of the panel that is pulling the joint together with enough force to produce a little squeeze out.
IMG_4461 by Hank Knight, on Flickr
This is why I don’t want a heavy glue application – a light glue application is sufficient to secure the joint and it avoids a big, messy clean up. When the taping is done, I place a couple of flat boards on the panel and add a heavy weight to keep the panel flat while the glue cures.
IMG_4460 by Hank Knight, on Flickr
I can handle it after about an hour, but I’m going to let this sit overnight before I cut the panels to final size and install them in the frame.
I’ve used rub joints for thin panels and clamping jigs with wedges. These both work (except maybe the rub joints), but this stretchy tape method is simple, requires no fancy jigs or equipment and it works every time. I’ve used it on thicker panels, but I prefer clamps for anything over about 1/2”. This is my preferred method for thiner stock.
Hope you find this helpful.
Hank