Material Guide
Why Shops Move From Zinc to Magnesium Plate
SGZ makes both zinc and magnesium photoengraving plate, and states plainly that magnesium is lighter and etches faster than zinc. For a shop whose bottleneck is bath time, that is the whole argument. But switching changes more than the metal.
What you gain
Bath time. Magnesium removes metal faster than zinc, so plates clear the machine sooner and the same bath turns out more work per shift.
Weight. A magnesium sheet of the same size is lighter than zinc, which matters when an operator lifts plates onto the machine all day.
Range. Coated magnesium reaches 10 mm, against 3.0 mm for coated zinc, and uncoated magnesium reaches 2000 x 1500 mm from 0.5 mm thick.
What you have to change
The additive. Zinc additives do not work on magnesium. SGZ names X-Flex, the Fuji Hunt product model E004, and Rev-Flex, the MEL product model E003, for its magnesium plate. Both ship in 5 gallon and 20 kg drums.
The back-side expectation. Coated magnesium comes with green anti-acid painting. There is no peelable red film option on that grade, which zinc offers.
Manganese content
SGZ notes that magnesium plate with low manganese content gives better etching results. If the work is fine-line, ask for that grade when you order the uncoated polished plate.
What stays the same
The machine. The BS powderless etching machine is specified for zinc, copper and magnesium, so you do not need a second bath to run magnesium. Change the additive and keep the same rotation, temperature and time controls.
Seeing it before you commit
SGZ opened a magnesium plate etching demonstration workshop in December 2016 and publishes a complete magnesium etching video. If you are switching a production line, watch the etch before you order a container.
Products Referenced in This Guide
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.
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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.
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Etching Additive Oil
X-Flex Magnesium Etching Additive Oil
Fuji Hunt X-Flex model E004 magnesium etching additive, 5 gal / 20 kg drum.
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Etching Additive Oil
Rev-Flex Magnesium Etching Additive Oil
MEL Rev-Flex model E003 magnesium etching additive, 5 gal / 20 kg drum.
View product →Answers
Questions About This Guide
How much thicker can coated magnesium go than coated zinc?
Coated magnesium runs to 10 mm. Coated zinc runs to 3.0 mm.
Can I use my zinc additive on magnesium plate?
No. Use X-Flex (E004) or Rev-Flex (E003).
Do I need a different etching machine?
No. The BS powderless machine is specified for zinc, copper and magnesium.
Does manganese content matter?
Yes. SGZ states that low manganese magnesium plate gives better etching results.
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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 →Put This Into a Quotation
SGZ quotes plate, developer, additive and machine together. Send the sizes and the volume and you will get one price for the line.