” Shrinking ” a Strip to Make for a Good Corner

I’m hanging wallpaper moving from right to left. The wallpaper is 21″ wide. The width between my last strip (over the door) and the corner is 19″ wide. This means that my next strip is going to wrap around the corner by 2″.
This is not good. You never want to wrap wallpaper around an inside corner, especially a tiny amount like 2″. Corners are never straight, and thus the wrapped bit will be warped and un-straight. The next strip will never butt up correctly with it, leaving gaps and overlaps. You will also end up with a new strip that is not hanging plumb.
Also, wrapping around corners doesn’t allow for movement in the corner as the temperature changes in the room, or as the house shifts on its foundation.
The goal is to wrap the corner by about 1/16″ – 1/8″, and then overlap the new strip on top of that narrow wrap.

This is how I want my strip to land in the left corner.
Bottom line – if I want my next strip to wrap just 1/8″ around the corner on the left, then it’s going to overlap by 2″ onto the existing strip on the right. If that happens, we’ll lose 2″ of the pattern and have some eye-jarring cut-off pattern motifs.

So, somewhere, I need to “lose” 2″ of paper. Looking at the short seam above this window, I see where I can remove some paper without messing up the pattern too much.

I’ve removed the strip and used my straightedge and a razor blade to slice off 3/4″ of paper.
The blue plastic is there to keep paste off my table, and the shiny thing is a protective plastic strip I use to keep from cutting into the wooden table.

3/4″ removed.

Slid back together, you don’t much notice the very minor pattern mis-match created by the absence of the narrow strip.
This could work on a longer strip as well, depending on the pattern motifs.

Now the left corner is how I want it.

But the right edge of the strip is overlapping 1″ or more over the existing strip over the window. You can see there is a pattern mis-match, not to mention a bump where these two pieces overlap. So I’m going to do a double cut and splice these two strips together.

Splicing means you press hard to cut through both layers of wallpaper. Your blade will probably cut a bit deeper and dig into the wall, scoring the surface. This is bad, because an un-intact surface can give way when wallpaper paste dries and the material shrinks, tugging at the surface. This can actually cause layers of the wall to come apart ( delaminate ), which means the wallpaper will come up at the seam. Do a Search here to learn more.
To prevent this, I’m using a Boggess Strip (a clear, thin, flexible strip of polycarbonate Lexon plastic padding ) to put under where the splice will take place, to protect the wall. You can’t cut through this stuff!

The strip in place.

I’ve smoothed the left strip back into place overlapping the existing strip. Next I’ve used a short straightedge and a sharp (important) new (important) single edged razor blade to slice through both layers of wallpaper. Here I’m removing the top strip of excess cut-off paper.

Now I’ve pulled back part of the strip on the left so I can remove the excess wallpaper on the bottom. Note that the cut is a little uneven in areas, to cut around the leaves in the design.

Removing the Boggess Strip. This does put tension on your wall, so you’ve got to have a good wallpaper primer underneath, applied over a sound surface.

The two strips smoothed back together.

The view from below.

I used a pencil to touch up the edges of the leaves, to make them look more rounded and natural.

The polycarbonate strips are named after the inventor, Steve Boggess, a colleague and fellow member of the Wallcovering Installers Association. Get them here: https://www.steveboggesspaperhanging.com/lexanpage.htm