Photo Papers
Photo paper is a complex material, composed of several different layers. With changes in the surrounding environment (humidity, temperature) photo paper is subject to changes in dimensions - growing and shrinking. On a typical 15cm x 10cm print this is hardly noticeable, however from 30cm upwards it becomes a problem. The mechanism is fairly complex, with different effects with increasing humidity and reducing humidity and the result is the formation of virtually permanent waves or wrinkles over the whole surface of the print, appearing after a few weeks or months.
In order to avoid these annoying waves, which ruin the look of the print, it is vital to correctly prepare the print before faming or hanging. It must be bonded firmly and definitively onto a suitable rigid backing. The dimensional changes are so strong, especially with a 70cm x 50cm poster, that normal glueing using everyday materials (even the spray adhesives sold specifically for photo mounting) is not sufficient – don’t even bother trying… Here is the method we have found. A good picture framing workshop will also be able to do this sort of work.
|
Method:
For the foam-board, take care not to dent it by grasping it tightly between your fingers. It’s fragile and must remain perfectly smooth and without blemishes. The work area must be scrupulously clean. The main worry is to avoid getting dust or debris between the print and the backing during the bonding. A small grain of dust makes a very visible lump on a glossy print. (Fluff-free clothes, tied back hair and clean hands are recommended !)
Cut a piece of backing material exactly to the nominal dimensions of the print (craft knife with a new blade, and a metal rule). These nominal dimensions correspond to standard frame sizes (40 x 30, 50 x 40, 70 x 50). The print will be a few millimeters bigger.
Take the print, image side down and carefully wipe the back with a soft lint-free cloth. Inspect the surface using a work light to make sure there are no remaining debris or dust.
Take the backing panel and, on the smaller edge, peel and fold back about 2 cm of the protective paper, exposing the adhesive. Position the backing over the print, adjusting the position to equalize the few mm of excess print all round. Press the exposed adhesive area of the backing panel onto the print to fix it in position. Turn the whole thing over.
Grasp the end of the backing paper, under the print on each side, and peel back another 2 to 3 cm. Smooth out the print onto the exposed adhesive, from the center to the edges using a soft lint-free cloth (tee-shirt is ideal). Repeat this step, a few cm at a time until you have stuck the whole print. For 70cm x 50cm prints, two people make the job easier – one to pull the backing, one to smooth the print. Press over the whole area with the cloth to ensure that it is correctly bonded. For the foam board, take care not to dent or crush it. It is possible that the cloth will leave micro-scratches on the surface – they are inevitable and only visible really close-up.
Turn the bonded print over, face to the table, and trim off the surplus around the edge, allowing the knife to follow the edge of the backing.
Framing
For prints mounted on CARFIX, the framing presents no difficulty as the overall thickness is still reasonable and it will fit into the frame rebate as normal. For prints mounted on foam board, the total thickness won’t allow the standard frame fixings to be used. For most frames, the glass / mounted print / MDF backing panel will completely fill the rebate and be flush with the back face of the frame. If you choose a wooden frame, you can simply insert drawing pins around the frame, with the heads overhanging onto the MDF backing panel to fix the assembly in place.
|
Contact with the glass :
Posters with an integrated border are not designed to have a window mount, which means that the print is in contact with the glass. The purists will say that you should never do this – but they are talking about “fine-art” prints that need perfect conservation…. The only worry here is the presence of “water-marks” (for want of a better term) if the print is firmly pressed against the glass. These are spots where the air is completely pushed out between the two, making it refract the light differently. If the frame fixings are not too tight this will only rarely appear. These “water-marks” are more noticeable on a white background than a black one. You can completely avoid this problem by adding a strip of CARFIX, about 3 or 4mm wide, all round the edge of the print on the front face to act as a spacer between the print and the glass.
|