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I have no experience with working with the StewMc Self-adhesive Mylar plastic sheets for making steel-string guitar pickguards. But my client wants one on his new guitar I'm building.

StewMc has instructions for installing them dry and also installing them wet (flooded with water and a few drops of detergent). They say cut with scissors or a razor knife. How do you cut and install this thin Mylar clear material? Most of the videos I have seen, including Frank Ford's, show the wet method.

What tips do you have to help me avoid a problems with this clear pickguard material like:

- cutting the edges smoothly to the desired size (can the edges be sanded like other pickguard material or is the Mylar too thin?)

- visible bubbles under the guard after installation (the dry method called for puncturing the bubbles which would cause a visible puncture flaw, right? Does the wet method avoid all bubbles?)

- starting the installation slightly out of alignment causing the need to remove it and start over (does the wet method allow for easy repositioning? I don't want to ruin a new finish due to removing a misaligned guard.)

Any tips from you experience would be appreciated.

I use those exclusively on my guitars. Cutting a clean outline is the biggest problem I have. I draw the outline on the paper side (the backside) and cut with that side up with very sharp scissors. I clean up any rough areas by lightly touching the edge to the belt sander—it’s easy to get dirt on the adhesive here—be careful.

Make sure the work area and the guitar top are completely clean. You won’t be able to get dust off of the adhesive.

I spritz some water onto the pickguard area on the guitar top, then rub some liquid soap into the water (the soap reduces the water tension) and smear the whole pickguard area so that a film of water/soap covers it all. I fold back the cover paper half way exposing the adhesive on the narrow part of the pickguard. That allows me to put the pickguard on the top and slide it around to align in before I press the exposed adhesive down when the placement is right. At this point, it’s easy to move the pickguard around—the water keeps the adhesive from fully grabbing. Holding the part with the exposed adhesive down (with the soapy water it can still slide), I pull the remaining paper off (pulling away from the part already attached. Watch carefully to ensure that the pickguard didn’t move out of position. It can still be slipped around or removed at this point.

When all is good, I start working the bubbles out from the center to the edges by pushing across with my thumb or a wadded paper towel, wiping dry the water as it comes to the edges. There will be some lighter spaces (air) even after all of the bubbles are removed. These will disappear over time (days) as the water dries out and the adhesive is pressed tight.

This is over a Target EM6000 finish. I haven’t done it on any other finish.

I am fortunate that my customers accept a little roughness on the edges as evidence of a handmade guitar. I don’t think I will ever make a perfect one.

Hi Ed,

I cheat and cut pickguards using a drag knife on my cnc. I cut mine from .0025” adhesive back Mylar. Nice and thin yet protective enough for the non-ham fisted player.

For installation I use Frank’s method. https://www.youtube.com/watch?v=c9XKuourJs4

Best, M

I install them dry. Carefully position the guard and hold in place with a masking tape hinge. Fold it back, make sure there is not a speck of lint, peel the backing paper at the corner, and then carefully work down the guard, peeling the paper and pressing out the air as you go. There will be some very small areas, not really bubbles, that go away in a few days as the last traces of air evaporate and the adhesive bonds. I use these over nitro.

For shaping, I use a pair of very sharp scissors. You can use a sharp razor blade as a scraper to smooth edges. These are too thin to bevel the edges.

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It will probably be alright.

+1. These are all we use too, and I found an old can of stain that is the right diameter for the spot on the rosette where I want the pick guard to stop. I make a couple tick marks where that arc starts and stops while the pick guard is laying on the body and then use a razor blade and the can to cut that arc.