The Choice Between Aluminum or Stainless Steel Plates

[Karura]

Hello!

At some point in time, those who have contemplated custom keyboards, or have taken a look at Korean custom keyboards should have come across the question: Do I want an Aluminum (Al) or Stainless Steel (SUS) plate?

I feel that some custom keyboard makers such as OTD has consistently offered Al plates for reasons unknown to me, so I assume that a plate with the stiffer material (Ti even) will not automatically make it a better material to use.

My preliminary research, observation and conversation with members of the community (including kin25, quochung and others) have yielded the following sentiments (just a short list of some):


Al:

• Al plate feels better to type on
• Al plate has more colour choices (anodizing)
• For tactile switches (brown/clear), Al is preferable

SUS:

• SUS plate is a lot more rigid and durable (great for putting on and taking off keycaps)
• For linear switches (red/black), SUS is preferable

Although the choice of feel is always subjective to the user, for the sake of generating discussion, I want to pose the question:
Is Aluminum or Stainless Steel the better material for plates, and why?

[Giorgio]

Stainless steel, when not kept perfectly clean, rusts.

I'm not sure that the rigidity of steel is so desirable, since it resonates more than aluminium, and it dissipates the vibrations with less efficiency. I'm sure that steel pings much more than alu.

[CPTBadAss]

I prefer stainless steel as I like the rigidity and weight. The aluminum plate I have is very very light and I'm not a huge fan of it.

Stainless steel, when not kept perfectly clean, rusts.

I'm not sure that the rigidity of steel is so desirable, since it resonates more than aluminium, and it dissipates the vibrations with less efficiency. I'm sure that steel pings much more than alu.

I've never had any issues with rusting or pinging with a stainless steel plate. Not sure if you've experienced that or not.

[nubbinator]

Stainless steel, when not kept perfectly clean, rusts.

Depends on the stainless.  T304 should not rust.

[CPTBadAss]

Depends on the stainless.  T304 should not rust.

Yup, please keep in mind narrowing it down to "aluminum" or "stainless steel" still leaves a lot of variables as there are tons of different variants of both metals.

[Giorgio]

T304 is not rust proof

http://www.meganracing.com/tech/faqs.asp?id=89

This must be the reason why steel plates in stock keyboards are usually painted

Stainless steel, when not kept perfectly clean, rusts.

Depends on the stainless.  T304 should not rust.

[CPTBadAss]

But...nothing is corrosion or wear proof. It's more resistant. Nubbinator said it *shouldn't* rust in normal use and unless you're in a super humid climate or using it at the beach, I don't see why it would.  Your board will be in a nice indoor environment, not an exhaust system or at the beach.

[HoffmanMyster]

Your board will be in a nice indoor environment, not an exhaust system or at the beach.

Don't tell me how to live my life.


I like both, they both have their pros and cons as has been outlined already. Steel feels rigid which is nice for a board meant to be "heavy" while aluminum can be nicer for typing feel and if you don't want the weight.

[zombimuncha]

What about fibreglass?

[Photekq]

It's entirely a matter of opinion.

I feel that some custom keyboard makers such as OTD has consistently offered Al plates for reasons unknown to me, so I assume that a plate with the stiffer material (Ti even) will not automatically make it a better material to use.

Also offered for some keyboards are partial (missing entire alpha cluster) polycarbonate plates. Evidently, rigidity isn't always favoured.

[Spopepro]

But...nothing is corrosion or wear proof. It's more resistant. Nubbinator said it *shouldn't* rust in normal use and unless you're in a super humid climate or using it at the beach, I don't see why it would.  Your board will be in a nice indoor environment, not an exhaust system or at the beach.

Heck, even plain old 4130 steel shouldn't corrode for years if kept indoors.  My high carbon steel knives don't as long as they are looked after.  If your SS keyboard is oxidizing... stop using it in a desalinization plant?

[Giorgio]

Not sure what happened here, but surely that's some ugly rust!





https://geekhack.org/index.php?topic=37861.msg725596#msg725596

[Tiramisuu]

I like the cheaper one.

[Giorgio]

If you get a quote for a custom cut plate, the price will be the nearly the same.

I like the cheaper one.

[Dreamre]

Al because of the colour options! You can also get thicker Al plates too.

[VoteForDavid]

Giorgio, either that is not a stainless steel plate, or someone is fooling around with strong acids/bases while typing.  That looks like some *mild* steel with an uncleaned-up soda spill right there.

Most of my experience with stainless steels are either high end knife steels that don't rust, or 316L valve bodies that will adsorb contamination but you won't catch it rusting in most environments.  "Stainless" is a pretty broad term.

[Karura]

For the record, I am not really talking about your run of the mill mass-produced keyboard plates that come with questionable quality of metals

I only mean the very best custom keyboard parts that are hopefully made with carefully chosen corrosion-resistant high quality material

[Giorgio]

Analyzing what happens in industrially made keyboards is a good way to understand what could happen with custom keyboards.

Custom keyboards are not better by definition, I haven't seen many artisans specify exactly what kind of metal they use.

For the record, I am not really talking about your run of the mill mass-produced keyboard plates that come with questionable quality of metals

I only mean the very best custom keyboard parts that are hopefully made with carefully chosen corrosion-resistant high quality material

[njbair]

The plate inside a Model M is mild steel. Some of those are in really bad shape after 25+ years, while others look fine. It really does have everything to do with the environment the keyboard is subjected to.

[Giorgio]

It can't be thicker that 1.5-1.6mm. You can make a thicker plate, but I will be very difficult, because you need to make some very special notches in order to allow the switch to click-in, even more complicated than that if you want to allow the switch top removal without desoldering.

Al because of the colour options! You can also get thicker Al plates too.

[CPTBadAss]

Al because of the colour options! You can also get thicker Al plates too.

You can always powercoat steel. Just as many colors .

I haven't seen many artisans specify exactly what kind of metal they use.

There are plenty of custom boards which say what metals they use. For example, I believe most of the LZ and KMAC boards are aluminum 6061T6. Here's an example where Duck states he uses Aluminum 6061 for the housing on his Duck Viper and Eagle.

[jonathanyu]

I prefer plateless or acrylic plate, but if I need to choose between aluminium and stainless steel, I would chose aluminium

[FoC_Tow]

Al:

• Al plate feels better to type on
• Al plate has more colour choices (anodizing)
• For tactile switches (brown/clear), Al is preferable

SUS:

• SUS plate is a lot more rigid and durable (great for putting on and taking off keycaps)
• For linear switches (red/black), SUS is preferable

Im confused why you would pick Al rather for tactile and SUS for linear switches tbh?

Al plates should give you a softer feeling, especially on bottom outs which (depending on preference) could be preferable for any switch type but linear is usually more prone to get bottomed out.
SOS plates give you a heavier, more solid feeling board (as well as being easier to design and work with) and should also make for a very crisp/less-dampened tactile feedback.

In my opinion its very much a question of preference as well as case design, but if I had to make a suggestion based on switches I would personally probably go the exact opposite route.

Al because of the colour options! You can also get thicker Al plates too.

You can always powercoat steel. Just as many colors .

Just as many colors +1 actually!* 
Don't forget those smexy white powder coats CPT! 

[Karura]

I'm not the one who said those; it's the Korean community's collective guidelines for custom keyboards.

I assume Al dampen the bottoming out, so it makes sense to me to have dampening for that.

Linear switches feel smoother the more rigid the keyboard is, so it also makes sense why people prefer SUS to keep the switch stable.

[tp4tissue]

The material for Plates DO NOT matter..

As long as there IS a plate,  ur g2g..


Rigidity, resonance,  all non-issues, because the difference is so small, you'd never feel it unless you're actively looking for it,  No one actually uses a keyboard that way... 

It's like you scrutinize everything about a toaster before you buy it..  but then you forget all about that, because hell you're just making toast..

Same with the keyboard..  You're just using wasd 12345  qe  zxb,   

[FoC_Tow]

Not sure if you notice much difference during actuation of a linear switch since you are just working against the resistance of the spring (no friction from a tactile actuation point) so I believe it should mainly affect bottom outs on linears. If there is a noticeable difference except for bottom outs tho shouldn't soft feel even smoother vs hard feeling more direct/precise?

I can understand why people might prefer Al for tactile switches as it would for clicky switches for example dampen the sound slightly and most likely result in a deeper tone.

After all, it probably comes down to personal preference in the end either way, but I just have to wonder about the train of thought behind recommending hard for linear in general. =)

The material for Plates DO NOT matter.. 

I wouldn't totally agree, but imo its a question of the case design in general. Cases can have a huge impact on feeling and sound (resonance, stiffness etc) but the plate alone is not a determining factor for this.

For example a stainless plate might lead to very different result using a Al vs acrylic/polycarbonate case.
An Al plate might lead to very different result depending on the how much flex the mounting points allow for. (mounted all around vs only top & bottom for example)

What about mounting a stainless plate, using O-Ring dampeners on the screws btw?
(actually sounds kinda interesting, rugged plate yet dampened feel...?)

[Elrick]

Not sure what happened here, but surely that's some ugly rust!

Show Image

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https://geekhack.org/index.php?topic=37861.msg725596#msg725596

You have just shown some CoolerMaster XT or Storm Quickfire type of corrosion which is quite common due to  the low standard of steel used as a plate for their switches.   They just used standard mild steel with paint applied and like an old Holden Kingswood, will start rusting away soon as you open the box to use it.

Real Stainless Steel Plate is exactly that, 100% "Stainless" free from any normal corrosion for decades to come.  Good note to only buy from decent Korean or Japanese manufacturers because they actually use Stainless Steel when specified.

[Touch_It]

IMO steel.  But that is for the weight.  I like my boards nice and heavy.

[Spopepro]

So... the whole thing about "ringing" and such has got to be psychosomatic.  Aluminum has a dampening factor of ~.004, and steel ~.008.  Steel will resonate less than aluminum.

However...

Aluminum sandwiched between other materials with different resonant qualities can have very, very good dampening properties.  There's a little bit of that going on, but they often aren't firmly coupled enough to really make a difference.

I don't think you could successfully get people to tell the difference between aluminum and steel plates from feel and sound alone in a blind test.