MITRA Forum Question Details

I do believe that what you want to achieve is doable. First, if I had my way I would suggest a heavier weight, cotton rag paper to begin with but the 140 lb. will likely work. The heavier the paper, the more rigid the primary support. The wooden secondary support will help to offset this.

I do not think that this is overly complicated.   You should make some tests first to determine if the adhesive will stain or change the appearance of the paper substrate. Make sure to test any adhesives that you intend on using on a scrap piece of the same rag paper that is sized or coated (eg with an acrylic dispersion “gesso” ground if you used one). The wooden panel should be well sized, I would probably use an acrylic solution like B-72 in acetone (or a spray like Lascaux) or an acrylic dispersion gel medium. Let this completely dry before moving on. One could also use a PVA dispersion size. I would then adhere the paper support to the panel with an acrylic dispersion gel medium if that passed your initial test. Care must be taken to make sure that the paper does not wrinkle or developer a fold when you are pressing it to the panel. You should gently press the paper to the panel starting from the center towards the edges. You may even use a brayer as a last step as long as this is done very gently. Remove excess adhesive that has oozed out around the edges of the paper. I would cover the face of the painted paper with a blotter and weigh down the whole for a day or so to eliminate the chances of buckling or warping.  

​Your first question: Yes this is what we mean by sizing/priming the paper.
Second: It would likely be fine to use your primed birch panels...were these purchased pre-primed or did you prime them yourself? You might make a note of this on the back of the panel (including any of the other materials you are using) as this would help to inform future conservators should your oil on paper need to be removed. You should consider lightly sanding the acrylic gesso to get a smoother surface, then apply a layer of acrylic gel medium to cut the absorbency. Wait for this to dry and apply another layer of gel medium before adhering your paper substrate (following the same directions as above).

​Actually these materials can be reversed (although not easily...and it takes having a Masters degree in conservation to know how to do it properly!)...Just to give you some possible scenarios as to WHY it may need to be reversed:

1) The Birch ply support becomes compromised and develops splits/warping/cracks, etc. and risks imparting damage to the oil on paper.

2) If the particular type of acrylic gesso is one of poor quality (there are many, many, brands out there these days) it may have an adverse effect on the oil on paper (although this is less likely to occur with a layer of good quality acrylic gel medium in between).

As per your second question...yes we mean for you to use the fluid acrylic gel medium....the kind you can add to acrylic paints. I would avoid using matte although it would likely work as well...matte mediums tend to be bulked with fumed silica and have a toothy surface when they set...this would make for a less successful bond with your paper substrate.

​You CAN use Jade (PVA) but then again you adding yet another material into the mix if you are already working with acrylic gesso anyhow. Your bond will likely be more chemically "successful" if you use acrylic gel medium but you can certainly test a sacrificial piece of paper and try it out (after sanding the gesso a bit).

​The gelled form of acrylic dispersion medium is preferable as it fills any voids and can create a better bond. You could use a fluid medium as well, but I would go with the gel.

​Yes my apologies...the GEL medium would be better (thicker consistency).

​Yes we are aware of the confusing terminology :) hopefully we have been able to provide you with some useful info to help you proceed...

Either a high-quality acrylic dispersion gel medium or a pH neutral PVA adhesive would be good options.