Some more of my ideas

[Tenka]

I wonder how the fiber-reinforced plastic feels.

Very good. I got too whistles made out of carbon-fiber-reinforced polymer.

They feel and sound beautiful and are light weight although you could batter someone with the Low-D whistle without damaging it at all.

What sort of good?  Do they feel like aluminum?  Cold to the touch?

 

[mclien]

Here some important things not to confuse: there a 2 very different sorts of fiber (for this consideration, it even don't matter WHAt kind of fiber is used) reinforced plastics:

1. a mixture of resin and very short fibers (normally <1mm in lenght) which are injetable into a mold

2. a fabric woven out of "endless" fibers, which is then (with diffrent procedures) embedded into a matrix of resin

Both variants are lighter than metal (specific wieght, from mind: plastics about 1,5/ magnesium 1.8/ alluminim 2,7/ titanium 4,5/ steel 7,65) I tent to forget the exact unit.

The reults are:

1. no visible fibers, one monochrome color, surface is harder than unreinfoced plastics, strenght/stiffness is better, too. But it's not sure it's better as metal, I gess not

2. visible fibers (when used with dlear resin), surface like the resin (untill you hit the fiber , of course), strengthstiffness better than all the others (even than steel, if made propperly).

To shininess: aluminium and plastic are about the same when it comes to scratches (unless you use anodizesed aluminium,which is mate or expensive when "shiny" anodiszed). reinforced material as in 1 will be a bit better, since the fibers are near the surface and harden it somehow.

Last note to the 2. Material: there are a lot of design fabrics like aluminuim coated glasfiber (I#ll take some pictures, when back home). Kind of loooks like a material woven from aluminum twill.

 

[mclien]

I wonder how the fiber-reinforced plastic feels.

Very good. I got too whistles made out of carbon-fiber-reinforced polymer.

They feel and sound beautiful and are light weight although you could batter someone with the Low-D whistle without damaging it at all.

What sort of good?  Do they feel like aluminum?  Cold to the touch?

From temprature same as plastic (what is in fact partly is made of), from hardness simmelar to aluminum (depends on fiber percentage of fibers in the material. the more fibre, the more hardness)

 

[xiongxioi]

Before we got all excited for this "fibre-reinforced plastic", no one has ever made a reinforced plastic as case for small devices commercially.

Sure, it is not easy to crack it, but we have better chance making the cases out of carbon fabre than reinforced plastic.

What ever reinforced plastic is, it is still plastic, it still feels like plastic, it still looks like plastic. I would choose aluminium for it's metallic feel and nothing else.

If we want strentgh, most industrial standard plastics with decent case design would be sufficent. Pandora's plastic is hard, but very brittle, the case has several thin parts with large residual stress.

If we want a cost effective method that also looks good, we need to choose in what way we want the finishing be. Not just paint it blue and call it a day. However, finishings good as the 3ds or vita may cost quite a bit, it all depends on what ed can get his hands on.

 

[_wb_]

I guess the type 1 is easier to work with (so cheaper to produce and easier to design for) and still better than what we have in the Pandora 1 in every way but maybe not as good as aluminium in terms of strength.

Type 2 is harder to do (more suitable for something like a bike) but could be even stronger.

I'm assuming ED was talking about type 1.

If it's going to be significantly stronger than the current cases, that's probably strong enough. When the strength is reached to make cracks virtually impossible and to survive 1 or 2 meter drops, scratch resistance and overall cost are probably more important criteria. There is no point in making a super-strong case that is able to survive 100 meter falls, if that means it's going to cost 300 EUR for the case alone, and if it still gets scratches easily.

Anyway, I don't like the cold feel of metal for a handheld. Yes, it could also be an advantage that the case conducts heat well, but I don't want to have to run a cpu stress test for a minute or two just to get the device to feel not too icy, and then when I'm using it, have to make sure I don't get the cpu too hot for a human heat sink.

 

[xiongxioi]

 There is no point in making a super-strong case that is able to survive 100 meter falls, if that means it's going to cost 300 EUR for the case alone, and if it still gets scratches easily.

Anyway, I don't like the cold feel of metal for a handheld. Yes, it could also be an advantage that the case conducts heat well, but I don't want to have to run a cpu stress test for a minute or two just to get the device to feel not too icy, and then when I'm using it, have to make sure I don't get the cpu too hot for a human heat sink.

 A material's resistance to scratches depends solely on its hardness. So, whatever the kind of plastic or aluminium you are using, they will be scratched because neither aluminium nor plastic is hard. Materials like glass or ceramic are hard, but very brittle, so they are not good for this purpose either.

In other word, if people want pandora's case not to be scratched by some coins or keys, the material that the case is made off must be even harder than coins and keys which are made off copper and stainless steel. There are few materials that are harder than these and suitable for making into cases. A round about way would be put a soft silicon case over pandora's case.

On the other hand, the cracking of something, usually ties with a few factors: material strength (how hard you would have to stretch it before it fails), ductility, resistance to impacts, and most importantly, the case's design aka loading path. Pandora's case can be cracked rather easily is due to a few factors, such as the brittlenss of the plastic, how each part of the cases connect to others (those annoying little hooks). I would recon, using a more ductile plastic, getting rid of many of the small bits would help a lot in this case. Use screws instead of those hooks will make everyone's life easier, just make sure those bits that the screws go in aren't the critical load pathes.

I personally love the texture and look of metal, sure it's not very utilitarian, but it feels classy. However, I can deal with some nice polished plastic finishing as well; if this will please more people and make ED happy.

 

[mclien]

OK, I didn't mentioned itclearly: Type2 is (in my Opinion, baesd on my experience from experiments with small sized parts) for custom build cases only (at least here aka for  the pandora or its/hers successor(s)).

That was my intention starting this thread: http://boards.openpandora.org/topic/15036-carbon-fibre-case-considerations/

For the standard production clearly a no-go. The type1 is a nice idea, when not rising teh cost much (mold cost could be the show atopper, I guess)

 

[_wb_]

There is no point in making a super-strong case that is able to survive 100 meter falls, if that means it's going to cost 300 EUR for the case alone, and if it still gets scratches easily.


Anyway, I don't like the cold feel of metal for a handheld. Yes, it could also be an advantage that the case conducts heat well, but I don't want to have to run a cpu stress test for a minute or two just to get the device to feel not too icy, and then when I'm using it, have to make sure I don't get the cpu too hot for a human heat sink.

 A material's resistance to scratches depends solely on its hardness. So, whatever the kind of plastic or aluminium you are using, they will be scratched because neither aluminium nor plastic is hard. Materials like glass or ceramic are hard, but very brittle, so they are not good for this purpose either.

In other word, if people want pandora's case not to be scratched by some coins or keys, the material that the case is made off must be even harder than coins and keys which are made off copper and stainless steel. There are few materials that are harder than these and suitable for making into cases. A round about way would be put a soft silicon case over pandora's case.

Yes, but according to mclien, plastic with short carbon fibres in it is slightly better than regular plastic or aluminium in terms of hardness. Of course if you put it in a pocket together with your keys, it will still get scratched. But if it's more scratch resistant (even just a bit), and it also does not have a paint surface or whatever kind of surface different from the material itself that can be scratched away, then at least it will be much less likely to have visible scratches.

On the other hand, the cracking of something, usually ties with a few factors: material strength (how hard you would have to stretch it before it fails), ductility, resistance to impacts, and most importantly, the case's design aka loading path. Pandora's case can be cracked rather easily is due to a few factors, such as the brittlenss of the plastic, how each part of the cases connect to others (those annoying little hooks). I would recon, using a more ductile plastic, getting rid of many of the small bits would help a lot in this case. Use screws instead of those hooks will make everyone's life easier, just make sure those bits that the screws go in aren't the critical load pathes.


I personally love the texture and look of metal, sure it's not very utilitarian, but it feels classy. However, I can deal with some nice polished plastic finishing as well; if this will please more people and make ED happy.

I also like the look of metal, but I care more about function than about looks. I intend to use this device to use it, not to impress people with it.

For the same reason, I prefer non-glossy finishes: I don't want to have to clean the surface all the time or get fingerprints on it, and I want as little distraction from the screen as possible: a dark matte bezel is best, please no bright glossy colors anywhere near my screen!

 

[WizardStan]

It could be as well that whatever instruments you have to measure the quality of the sound do not account for the overall quality but only some aspects of it

If the audio wave is exactly identical, I cannot begin to think what else you could possibly measure. Are you suggesting that there is some ethereal component to audio that simply cannot be recorded and compared by a machine, that only a human can tell the difference between two seemingly identical sounds?

if you blind people, ask them to rate what sound is better from 2 different sources... and if they spot a difference, it means that your tests don't cover everything

Except that we frequently see the opposite. When people know what they're listening to they will claim to hear a difference but in blind test after blind test they cannot tell the difference.
I still have no idea what we're arguing for. Is there a point to whether or not bluetooth audio can be deemed reasonable or not?

 

[EssoAir]

It could be as well that whatever instruments you have to measure the quality of the sound do not account for the overall quality but only some aspects of it

If the audio wave is exactly identical, I cannot begin to think what else you could possibly measure. Are you suggesting that there is some ethereal component to audio that simply cannot be recorded and compared by a machine, that only a human can tell the difference between two seemingly identical sounds?

if you blind people, ask them to rate what sound is better from 2 different sources... and if they spot a difference, it means that your tests don't cover everything

Except that we frequently see the opposite. When people know what they're listening to they will claim to hear a difference but in blind test after blind test they cannot tell the difference.

I still have no idea what we're arguing for. Is there a point to whether or not bluetooth audio can be deemed reasonable or not?

bluetooth audio is not tho. I have so few bluetooth devices (only one I can think of is my Pebble). I use 3.5mm AUX for everything. im cool with the addition of blurtooth audio, but I dont want to buy an expensive headset only to add ONE more thing to my list if battery operated devices.

 

[mclien]

To the carbon short fibre material:

I could do a test part. I still have my mold from the abacus Wrist watch packplate. And I think I have a bag of schort carbon fibres also. I could do a homemade testing part from that and epoxy resin. It is about 50x40mm, weight next to nothing and fits perfectly into an envelope, which could be send around in the community....

 

[Klumpen]

I wonder how the fiber-reinforced plastic feels.

Very good. I got too whistles made out of carbon-fiber-reinforced polymer.

They feel and sound beautiful and are light weight although you could batter someone with the Low-D whistle without damaging it at all.

What sort of good?  Do they feel like aluminum?  Cold to the touch?

Same temperature as plastic, so warm to the touch and more comfortable and way more sturdy (visible fibers) than aluminium.

 

[Grench]

To the carbon short fibre material:

I could do a test part. I still have my mold from the abacus Wrist watch packplate. And I think I have a bag of schort carbon fibres also. I could do a homemade testing part from that and epoxy resin. It is about 50x40mm, weight next to nothing and fits perfectly into an envelope, which could be send around in the community....

Odd question - how does hit hold up to being threaded with/by/for machine screws? Will threads need to be created with a tap, or can the screws self-thread?

It's been a common issue with the old cases that on re-assembly people will strip the screws as the old plastic doesn't hold much for threads. A disadvantage of aluminum (or any metal) is that there is machining costs associated with creating/machining threads after molding.

Where does the CF material sit in relation to machine screws for assembly?

 

[Klumpen]

Please not screwing inside of the plastic anymore, there are alternatives.

 

[comradekingu]

Such as? Screws are user servicable, thats a good thing for them.

 

[Klumpen]

Such as? Screws are user servicable, thats a good thing for them.

Screws yes, but metal inserts on the other side, there are flat ones available.

 

[Letalis Sonus]

Such as?

Metal inserts.
He didn't criticize the screws but the way they're being used.

Edit: Bah, too slow :/

 

[b_o_b]

I also like the look of metal, but I care more about function than about looks. I intend to use this device to use it, not to impress people with it.

Exactly!  I think we already determined this community wants a device that has functionality as its main feature. I don't have any problem paying an additional sum for improved cpu/gpu/keyboard/backlight/sturdiness/reliability/wifi/screen though.

 

[comradekingu]

What is a metal insert? Show pics. Whatever replaces screws needs to keep it together and keep the keyboard from flexing. Tool-less sounds good, but many of those solutions tend to be worse than the basic.

Metal is unfeasible for wireless signals. If one wants it there is no reason it cant be milled out of solid metal. Hoping the design files are available for that.

 

[TrashyMG]

What is a metal insert? Show pics.

It's literally adding a metal insert with machine screw threadings.. makes it more serviceable as it's not using a pointed screw driving directly into plastic.


I'll be for it as long as it doesn't add to thickness of the device.