Engraving Durability Testing on Stainless Steel & Aluminium
Engraving durability is something that comes-up on a regular basis at CNCROi.com so I thought it would be fun to do a video to show you just how annealed and etched stainless steel holds-up to extreme sand blasting and by extension, how it compares to anodized aluminium.
As you saw in the above video I made at the CNCROi.com shop, deeply etched 304 stainless steel outlasted them all, followed by lightly etched 304SS then anodized aluminium when exposed to 80 psi (pounds per square inch) of beach sand about an inch and a half away.
As this was just a material test, I used scraps that I use for testing engraving durability here in the shop.
When ever we get a new lens or come-up with something new, we test it on scrap plates so we don’t waste the good stuff.
As these 304SS plates were going to be sand blasted as well as etched and annealed, even if they had previous marks on them, it’s no big deal as we’ll work over them with our laser.
I previously etched these plates before these photos were taken, I just forgot to take pictures during the process but it didn’t matter as I had video already made and I was going to etch it again anyhow, just deeper.
The reason for going with this thicker plate as well was to not have it bend and warp on me during the annealing and etching processes happening on these 304SS plates.
Annealing produces a nice smooth result on 304SS while etching a rough surface texture, of course, the engraving durability is better than the annealing but overall, it’s the same in real world conditions.
They can of course be mixed and matched, meaning we can etch into the plate and then anneal the lowered surface but that doesn’t always work as there is some variance in the annealing due to the uneven surface of the etching.
The biggest difference between etching and annealing 304 stainless steel are the sparks produced, etching produces a lot more fireworks than annealing as we are vaporizing the surface.
Annealing is an oxidation process which etching we are actually engraving into the surface of the 304SS plate.
The speed of annealing and light etching is the same though, just one is done “in focus” while the other is “out of focus”.
Annealing is a more spread-out heat distribution, hence being done out of focus using our Austrian fiber laser source while etching is a focused beam of high energy at a specific point on the 304SS plate.
As for the resolution, we achieve the same but as the focus is slightly different depending on the process we etch or anneal the 304 stainless steel plate, the etching loses a little if you have extremely small details.
Regardless of the process, engraving durability is amazing on 304SS when exposed to real world environments, what I did in the video and this blog post with CNCROi.com‘s industrial sand blaster is an extreme not found in nature.
Now that we are etching deeper into the 304SS plate and doing repeated passes to gain additional depth, you can see why the metal is prone to warping at thinner gauges.
There is a lot of heat being pushed into this metal plate, thinner metal tends to bend upwards from all this intensity which also causes a change in focus, as the plate becomes a different distance in different areas to the head of the laser.
This is why, even with our stainless steel custom welding tags, we do annealing but are always careful not to have too much annealing happening on them.
Soon CNCROi.com will be releasing thicker custom welding tags though that we can comfortably etch and anneal far more of the surface area.
CNCROi.com keeps on coming-up with new solutions for our industrial clients who request options that just aren’t found in the marketplace, and that includes using exotic metals to fulfill their needs.
Our fiber laser is powerful enough to engrave through the tag, but that isn’t the purpose of these markings, what we want is a good depth for great engraving durability, not the production of an expensive stencil.
It’s the same with our welding tags, the goal is to offer a custom branding solution to welders and other clients, with the option to tack weld and or rivet to their work without costing and arm and a leg.
As it’s generally more difficult to clean a deeply engraved stainless steel plate, we use our industrial sand blaster to quickly clean the metal.
The surface is incredibly rough, which is what you want for engraving durability, but it also means you have an uneven surface with lots of areas for small particles to get stuck in or to rip cleaning fabric.
This is why, for most of our clients, they prefer the smooth finish produced by annealing to the etching roughness we can also fabricate on their behalf.
Personally, I prefer the annealing as it’s a relatively quick and cost-effective method or branding or identifying information on a custom metal plate vs the more costly and deeper engraving.
It all depends on the application which solution works best for you when it comes to engraving durability.
Regardless of the method used, using a sharp knife or plate, you aren’t removing any of this off the 304 stainless steel plates in this blog post, it’s incredibly hard and crazy durable.
You can see some other markings on these plates, again, these are scrap that we use internally for testing, the plates we produce for our customers are top quality made to spec in a variety of finishes, gauges and grades.
Depending on the angle of the reflection, you can see that the lightly etched or annealed 304SS plate becomes more visible, this is something that’s hard to evaluate in photographs or videos but they are totally interchangeable.
For custom 304SS machine tags, we anneal about 9 times out of 10, just because the surface quality is nice and smooth and is more clearly legible, especially for very fine details.
CNCROi.com offers a host of solutions when it comes to engraving durability at various price points, for some applications, we need to go full-on heavy metal while others, lamacoids do the job just fine.
If you are unsure of what you should be using for the best bang for your buck, just contact CNCROi.com and we’ll put our expertise and experience to work for you!
It’s wonderful having an industrial sand blaster that I can fit inside of in the shop, it allows us to clean-up plate for annealing and doubles as a paint and grinding booth as well! It’s multi-tasking at its greatest!
As the metal grid on our sand blaster can scratch metal, I generally lay a plastic grid table over it to make sure that everything we produce in the shop relating to sand blasting looks its finest.
Once the engraving durability test is finished within the CNCROi.com sand blaster, we can take a look at the results on both the 304 stainless steel and the anodized aluminium tags.
Our sand blaster was set to 80 psi (pounds per square inch) using just normal beach sand, this is still wicked overkill for these tags but keep in mind that if I had my bare hand in there doing what I did on these metal tags, I wouldn’t have any more skin and would be down to the bone!
It’s no surprise that the first to go was the annealing, this process is just on the upper surface of the stainless steel plate.
Engraving durability of annealing is AWESOME by the way, you can’t scratch it off with a sharp knife.
The second to go under these harsh conditions, was the etching, again, no surprise there, stainless steel is a very tough substance, it will take more than beach sand to wear down this metal plate!
Anything that was darker though on the stainless steel etching was removed, but the engraving aspect remained.
Lastly, the deep etching, again, no surprise, it outlasted them all!
Engraving durability is about several factors, the first is what your budget is, although etching and annealing are pretty close, that deep etching would cost significantly more than the other two options combined.
When it comes to engraving durability, the higher the budget or investment, the better the length of time the tag will last.
Again, looking at this stainless steel tag from another angle, you can clearly see that the etching is superior and that isn’t even the deepest we can go.
Another things to consider is that on the back of a machine, this will most likely never be exposed to anywhere near the amount of abuse I sustained onto this steel plate, I can’t think of anything in nature that would also apply as much pressure.
I did two plates like this for this engraving durability test on purpose, on the left, the 304 stainless steel tag put under sand blaster conditions, on the right, not touched at all.
Taking a closer look at the Z or N depending on your viewing angle, it REALLY LOOKS COOL after it has been sand blasted!
When I saw this, I already knew what I was going to do next in the shop, I’ll share that with you in a future blog post.
It’s hard to show this properly in photographs and video but you can still make-out the depth achieved on the 304SS after it has gone through our industrial engraving durability test.
And the metal business card sized plates at another angle, very positive results!
What’s really nice about our custom metal and aluminium tag solutions is that you can actually weld these to your work or rivet them, the choice is yours as they are produced on-demand with or without holes.
Annealing is great because there is nothing that will be vaporized during the welding process, CNCROi.com still leaves a slight border of material not annealed on our tags regardless, but unlike screen printing or UV printing, the etching and annealing will not be affected by the heat or fumes from welding.
What impresses me most about how well the sand blaster cleaned-up the etching on this custom yet scrap 304SS tag is how neat it really looks, I wasn’t expecting a very nice color like I achieved here, especially with the deep etching.
I have to say, I’m very happy I took time out of our busy schedule to do this engraving durability test!
In a very much last-minute decision, I thought it would be neat to see how the anodized aluminium would hold-up to the sand blaster as well, CNCROi.com does a lot of anodized aluminium engraving and marking!
If you are wondering how this was made, check this video out.
The engraving durability test was a surprise to me though, I didn’t expect that the anodization would come right off, it just shows you how strong both annealing and etching on 304 stainless steel really is!
This is the anodized aluminium plate straight out of the sand blaster, you can clearly see where I hit it with the sand blaster and how clean the result was.
Engraving durability test on this plate showed that it’s absolutely no match for 80 psi sand but hey, it was never meant to be to begin with so nothing really lost, only knowledge gained!
After cleaning the anodized aluminium plate, you can see how the central area of the sand blasting stream went right through the anodization and a few rings around where the pressure was less.
Here are all three of our brave Musketeers!
I’m very happy I did this test, other than the anodized aluminium surprise, it just re-enforced how durable our custom solutions are for our customers.
If this was screen or vinyl printing, the results would not even be on the same planet, that stuff comes right off under normal conditions. WE HAD TO USE AN INDUSTRIAL SAND BLASTER TO REMOVE OUR WORK!
How’s that for the ultimate engraving durability test!
Need some custom metal tags, plates and other awesome stuff? Contact CNCROi.com right now!
