Solution
Choosing Between Zinc and Magnesium Photoengraving Plate
Zinc and magnesium do the same job and are bought for different reasons. This is the comparison SGZ gives buyers who are moving between the two, using only the figures published on each plate specification.
Step by step
How SGZ Works Through It
Each step names the SGZ item that covers it, so you can price the whole route rather than guessing which parts you still have to source elsewhere.
Compare the thickness range
Coated zinc runs 0.8-3.0 mm and uncoated zinc to 7.0 mm. Coated magnesium runs 1.0-10 mm and uncoated magnesium from 0.5 mm.
Compare the sheet sizes
Zinc is stocked at 1000 x 500 mm and 1000 x 510 mm. Coated magnesium comes at 500 x 1000 mm, 610 x 457 mm and 610 x 914 mm, and uncoated magnesium runs to 2000 x 1500 mm.
Compare etch speed and weight
SGZ states that magnesium is lighter and etches faster than zinc. That is the main reason high-volume shops switch.
Compare the back-side options
Zinc offers anti-acid painting or a removable red film. Coated magnesium has green anti-acid painting.
Match the additive
Zinc runs with Velv-Etch (E002) or the SGZ house oil. Magnesium runs with X-Flex (E004) or Rev-Flex (E003). They are not interchangeable.
Check the developer
KY161 is specified as especially suited to SGZ etching zinc plate.
What you need to buy
Products in This Solution
Photoengraving Zinc Plate
Coated Zinc Plate for Engraving and Etching
Photoengraving zinc plate pre-coated with blue photoresist, 0.8-3.0 mm, with painted or filmed back.
View product →Photoengraving Magnesium Plate
Coated Magnesium Plate for Engraving and Etching
Blue hydro-coated photoengraving magnesium plate, 1.0-10 mm, green anti-acid back, faster etching than zinc.
View product →
Photoengraving Zinc Plate
Polished Zinc Plate for Engraving and Etching
Uncoated, polished photoengraving zinc plate, 99.95% purity, 0.8-7.0 mm, for CNC engraving or your own resist.
View product →
Photoengraving Magnesium Plate
Highly Polished Magnesium Plate for Engraving and Etching
Uncoated highly polished magnesium plate to 2000x1500 mm, from 0.5 mm, for CNC engraving and in-house resist.
View product →
Answers
Zinc or Magnesium Plate Selection Questions
Is magnesium always the better choice?
No. Magnesium etches faster and weighs less. Zinc is the traditional material for stamping and coining relief, is stocked in two sizes and offers a peelable red film on the back.
Which plate goes thicker?
Coated magnesium, at 10 mm, against 3.0 mm for coated zinc. On uncoated plate, zinc reaches 7.0 mm.
Which plate goes larger?
Uncoated magnesium, at 2000 x 1500 mm.
Do I need to change anything else if I switch?
Yes, the additive. Zinc additives do not work on magnesium and magnesium additives do not work on zinc.
Background Reading
Material Guide
Why Shops Move From Zinc to Magnesium Plate
Magnesium plate is lighter and etches faster than zinc, goes to 10 mm coated and 2000x1500 mm uncoated, and needs a...
Read more →Comparison Guide
Coated or Uncoated Photoengraving Plate
Coated plate arrives ready to expose but is limited in thickness and size. Uncoated plate is bare metal, goes thicker and larger,...
Read more →Zinc or Magnesium Plate Selection
Send SGZ the plate sizes, the volume and the metal. You will get a quotation covering plate, chemistry and machine together.