Switching from magnesium plates?

Here are some differences you'll find between the Boxcar Base system and magnesium plates.

Detail, detail, detail. You can hold finer lines, dots and letters in photopolymer. Expect a 2 pt. Times New Roman on our 94FL plate or a .2 point isolated line.

Our photopolymer plates are not permanently mounted to a printing base. This is different from wood magnesium plates! With polymer, you would purchase a reusable printing base that locks up in your chase. The printing plates are then mounted temporarily onto the base. Once the magnesium plates are processed, they generally are permanently mounted onto wood to create a type-high surface. Accurate inking of wood-mounted plates is, unfortunately, impossible.

The Boxcar Base 100% aluminum base provides a much more accurate, solid printing surface than wood. Wood warps with changes in humidity conditions. Using wood as a base requires a lot more make-ready than polymer.

Boxcar’s polymer plates take up less storage space. They can be stored in a filing cabinet! Magnesium plates are thicker and heavier than polymer.

After printing magnesium plates, you’ll have to coat them with an oil – such as Vaseline or vegetable oil – or else the plate will oxidize over time and render the plate unusable. Because most magnesium plates are mounted on wood, if you get carried away oiling your plate, the extra oil can sink into the wood and potentially warp the wood bases. Photopolymer needs no extra oils for storage. If you store your polymer plates in a ziplock bag in a cool, dark place, your plates will last indefinitely.

For those who care about keeping this Earth around: Boxcar’s polymer plates process in water, which afterwards is safe enough to pour down the drain. Magnesium plates require acids to etch the plate.

Magnesium plates are better suited than polymer for hot-foil stamping – they heat up more quickly and evenly and require a shorter dwell time. Because of this, vendors of magnesium plates can be more interested in working with hot foil stampers (who make up most of their business) than letterpress printers. We believe that for letterpress printing, photopolymer plates are easier to print and will, with professional platemaking, produce a higher quality printed piece in the end. And all we do pretty much is process polymer plates for letterpress, so know that you’ll be valued and understood at Boxcar Press!