I have glued 6mm renovation plasterboards on the walls in a bedroom and now I'm going to glue paper strips in the seams before applying putty. I plan to use Flügger Vävlim Extra 378 to glue the strips. What I wonder is... Should I putty and sand the space between the plasterboards (between the red lines in the picture) so that I get a smooth surface to glue the paper strip onto, or should I glue the paper strip directly without putty?
There should be filler in the gap. Painters usually, as @SvanteC writes, fill in the strip without using glue. It goes faster. But it's easier to succeed if you fill the gap, glue the strip, and then fill over. There are many drying times.
The risk is that the strip is sucked into the gap and doesn't become smooth, then it might move if you're unlucky, if it's smooth underneath the strip is stretched as it should be.
The risk is that the strip gets sucked into the gap and doesn't lay flat, and if you're unlucky, it can move; if it's smooth underneath, the strip will be stretched as it should be.
Thank you Stefan N and everyone else for the great tips.
Fill the small gap so that the surface you glue the strip to becomes smooth. Let the filler dry before gluing.
I have started doing that. It turns out very well and much stronger than placing the strip directly in the filler.
I did a test by pulling off the strip. The one that was only filler-plastered could almost be pulled off in its entire length. A strip glued with wood glue is impossible to pull off.
Wood glue dries quickly. I mixed in a little water and brushed it on the wall. Put up the strip and wiped it with a cloth.
I believe that wood glue is better than fabric glue or wallpaper adhesive.
I glue paper strips with våtrumsgrund, it is thin, waterproof, and sticks like nothing else. Another advantage I think is that you can "brush" the strip on the outside to easily remove all the air under the strip.
I seem to recall that the recommendation when gluing is NOT to brush on the top side to avoid banding due to different moisture absorption abilities between paper and glued paper. However, I haven't noticed any difference and happily continue to glue with strong fabric glue (Flügger 378) on both sides for proper reinforcement.