Full Version: oxidation of engraved messages
From: john (JHEIL2) [#1]
10 Mar 2006
To: ALL
Newby Question:
I was wondering what would be the best way to oxidize engraved messages on silver so that they would be more visible? Is there a laquered finish that could be engraved through so that the whole piece does not oxidize. What would you recommend that would be the most cost efficient way to do this?
From: Stunt Engraver (DGL) [#2]
10 Mar 2006
To: john (JHEIL2) [#1] 10 Mar 2006
If you're referring to Sterling, it would have to be coated, so the oxidizing solution wouldn't attack areas of the piece, other than the engraved image area.
From: john (JHEIL2) [#3]
10 Mar 2006
To: ALL
From: Harvey only (HARVEY-ONLY) [#4]
11 Mar 2006
To: john (JHEIL2) [#3] Unread
It must be a non-metallic coating to resistt the blackening solution. It takes a special coating, very thin at that, to allow engraving through it without chipping. That I leave to the suppliers.
Silver plated sterling silver is a weird item, I would wonder if it was sterling silver at all. No reason to put a silver plate on sterling silver.
The plating may be purer than sterling, which is 92.5% silver, but to what end?
From: Stunt Engraver (DGL) [#5]
11 Mar 2006
To: john (JHEIL2) [#3] Unread
John,
A professionally-applied lacquer coating is about all I can think of that would allow you to engrave and oxidize Sterling.
As Harvey says, metallic coatings, such as silverplate or rodium, won't resist the oxidizing solution.
Beyond a lacquer coating, the only way I've been able to produce black engraving on Sterling, or any uncoated metal, is route and color-fill.
EDITED: 11 Mar 2006 by DGL
From: logojohn [#6]
11 Mar 2006
To: john (JHEIL2) [#3] Unread
Aluminum will oxidize with fair results and better with an aluminum specific oxidizer.
I thought silver, stainless steel and others would not oxidize at all or very little. Some silver plated items are not solid silver or steel and may be a combination of metals with some brass, copper or other metal than might oxidize some.
Oxidizing is an old process. I think it is mainly made only for blackening diamond drag engraving into specially made high quality lacquer coated brass. I would be surprised if you could get it to work well with anything
done on the laser.
The groove of the diamond drag protects the oxidization from being rubbed off. Just removing the lacquer with a laser or even a burnisher leaves a wide stroke exposed. Usually it will not hold the oxidizer and may also look blotchy or a grayish non-black color when covering large non-dragged areas. I know others have said burnishing works, but I prefer things that work every time with predictable results. You also have more of a risk damaging a product with a rotating burnisher.
We can oxidize large areas of a logo or even 2" letters if there is a hatch fill with tightly spaced lines. We diamond drag with a non-rotating cutter with 1 pass but 2 applications of the oxidizer.
Especially on aluminum, less z axis pressure is better and will oxidize better than a deeper groove with gouged out edges.
The oxidizer will turn all exposed metal black.
Any item to be oxidized must have a high quality lacquer. I have tried to oxidize things like brass key chains, brass star paperweights and medals and even cheaply made brass plates sold with mass produced gifts.
Some have a very thin layer or no lacquer and the whole item will darken almost immediately when oxidized. Others may look fine at first but degrade over time. I put some oxidized brass key chains on display since they looked good at first. Yes, the oxidizer was thoroughly rinsed off but over time the oxidizer migrated under the lacquer around the letters and produced a blackened spider effect.
With experience we simply do not oxidize anything but engraving plate stock specially made for it. We just explain ahead of time to the customer what to expect. For example, engraving on stainless will be very light.
Most people have it done anyway and it is better than trying to explain later why their item is ruined.
For metal desk accessories and gifts we only offer to diamond drag engrave them with no color fill. Especially if you use a hatch filled true-type font, the silver on silver look provides an upscale look. The
contrast is not the best but it is a gift, not a directional sign someone needs to see across the room.
If you need a large quantity of anything in black or color marking it is best to order it from a supplier that is familiar with it and can screen, pad print or mark it in some other prooven way.
The engraving brass is not made for outdoors and will degrade quickly. We offer the outdoor antique gold plastic for outdoor signs and cast bronze as the expensive alternative.
.
From: Stunt Engraver (DGL) [#7]
11 Mar 2006
To: logojohn [#6] 11 Mar 2006
The good point you bring up is, "Why does everyone want black or dark lettering?"
That way, the image could be confused with much lesser processes, such as pad printing or silkscreen, where a nicely, diamond-drag-engraved item, stands on its own, as something unique.
From: logojohn [#8]
11 Mar 2006
To: Stunt Engraver (DGL) [#7] 11 Mar 2006
We display and offer laser engraved black brass and diamond dragged black brass plaques side by side. 95% choose the diamond drag plaques even with 3 line roman that is not nearly as bold as the lasered plaque.
With the spot lights we have on the plaque wall the reflection in the diamond drag gooves make them stand out.
People feel the lasered ones are a "printed item" and of lesser quality.
.
From: Stunt Engraver (DGL) [#9]
11 Mar 2006
To: logojohn [#8] 11 Mar 2006
John,
That's your second good point, in this thread. :-)
With the trend toward laser engraving equipment, being a startup's first (sometimes, only) piece of equipment, those who have diamond-drag/rotary capability are in a position to capitalize on its unique output.
In our ever-increasing world of sameness, it's a good idea (and crucial) to set ourselves apart from the pack.
That's one way to do it.
EDITED: 11 Mar 2006 by DGL