Screw decisions for assembly


comradekingu

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The pandora screws are regular types, and its easy enough to strip the screws. Considering where they are, its not that easy to mend the situation once damage is done.

Changing to pozidriv might help, and better, harder screws too.  Screwing into plastic isnt ideal, but thats harder to do anyhting about. A snap-together case is easier to do, but still a bit involved.

Hex keys are different from imperial to metric, so inevertably someone will strip them by doing it wrong, as many are not aware of this.

Maybe the back end of the new stylus could be a torx screwdriver and that could be a way to go with screws that are more resistant to stripping.

Also wondering what the pandora screw specs are, so that the wiki can be updated with where to get replacement ones.

https://en.wikipedia.org/wiki/List_of_screw_drives
 
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Screw decisions! Screw them, I say!!! We don't need no steenkin' decisions!!!

I have a box of 20mm x 3 torx screws in the workshop, with the slogan "Super screwing power!" proudly emblazed all over the box.

...sorry 'bout that. I'll go get my coffee now.
 
...sorry 'bout that. I'll go get my coffee now.
Already beat you to it. No, really. :p

Is snap on an option? Actually, I might not want the whole case be a snap on.
 
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Is snap on an option? Actually, I might not want the whole case be a snap on.
As ED specifically mentions an additional screw in the Pyras display lid as an improvement, I guess not.
 
Snap on stuff is a pain to get apart if it's at all sturdily made. You either end up with something that's fragile or hard to get into (I've a set of guitar picks, bent through use, for getting in to snap on devices).


So screw on for me please. The current Phillips drive screws aren't bad, but the problem with the ones in the deep wells especially at the front edge is that that well isn't always quite big enough not to grip the head of the screw as you try to unscrew it. You've a choice then of applying more pressure and risk stripping the threads, or less and risk the screwdriver falling out and stripping the head. If the head wasn't held by the case, that wouldn't be an issue, and a consistent pressure would keep the driver in while you unscrewed it.


I didn't know that the Phillips drive was designed to let the screwdriver slip out if the ratio of torque to downward pressure exceeds a certain amount to avoid over-tightening. Posidrive which was designed to not slip out would be a better choice if it really lets you apply more torque without increasing the pressure unnecessarily, though I must admit I've never really felt much of a difference between the two heads in use. Mind you, all my watchmaker screwdrivers only came in flat and Phillips heads, and the smallest metric Posidrive screwdriver I have is M5.
 
I don't know how widespread the Robertson head is in Europe (I know it isn't very common in the US) but it's an amazing screw and I'd be quite happy if it were considered. It used to annoy me having to have so many different sized square drivers until I realized that my ratio of stripped Phillips head to stripped Robertson was infinite.
 
I don't know how widespread the Robertson head is in Europe (I know it isn't very common in the US) but it's an amazing screw and I'd be quite happy if it were considered. It used to annoy me having to have so many different sized square drivers until I realized that my ratio of stripped Phillips head to stripped Robertson was infinite.
It's actually quite common in house building now in the US, but never seen it on machine threaded screws.
 
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I hope ED does not choose the cheapest solution unlike Pandora screws. All of the screw counterh oles are basicly destroyed due the poor plastic. My Pandora even had one ordinary wood screw when I recived the Device!  <_<   

I suggest to use metal inlays to sink the screws in and protect the plastic. Should be doable without much additional costs.
 
Metal inlays that need to be hammered in to precisely manufactured holes in the plastic sound exactly like the sort of small fiddly parts that ED has been eliminating in the Pyra's design.


Perhaps the case makers are able to do this at a small extra cost, but if not I wouldn't expect it to be something ED goes for.


There's nothing wrong with the Pandora's design if they made the wells properly and didn't ever use dodgy screws like chipboard screws (not that I found any in my Pandora). It would be even better if the screws were made out of tougher stuff like tool steel (though I suppose you don't want your Pyra's screws rusting), but there's nothing wrong with screwing into plastic for something the average user will only ever open at most a couple of times (and hopefully less if the Pyra is a bit more reliable than the Pandora).
 
We have Robertson heads on floor board screws (the kind of thin long screws you need to do an invisible fastening of floor boards by screwing diagonally in the tongue of a tongue-and-grove-board), and usually the screws hold up quite well, but the bits get quite round quite quickly. Also, when you hit something like a knot, it really struggles to deliver power from the screw driver to the screw without slipping. They can be made rather thin, though, so I understand its use in those cases.

My preferred screw (for generally screwy situations, that is - Not talking about the Pyra specifically here) is Torx, almost every time. If I can't get that, I want Pozidrive (then again, I usually work with wood). And yes, I do feel a big difference between Philips and Pozidrive :) but to get the benefits, one must make sure that one uses proper size and shape bits. In particular, a Philips screw driver to a pozidrive screw will kill it.
 
Robertson, Torx, or Pozidriv  are the most optimal in my opinion :) it would be awesome to get very high quality metal inlays for the screws. I think it would be great for both longevity and for people who mod or open their Pyra often. But I don't think EvilDragon will go for it. We should ask him if he can see with the case manufacturer! :­D
 
How much do we want to spend on having great screws so we can avoid wear and tear that eventually makes you have to replace a 10 EUR case after opening it too many times?

After all, while I like the idea of a hardware hacker friendly device a lot, I'm not a hardware hacker myself and I assume that most of the community is not. So even if it only costs 2 EUR extra per Pyra to get extremely wear-resistant screws, I'm not sure if it is worth it -- it may be better to let those who want to do a lot of open/close cycles buy a couple of spare cases, instead of letting everyone pay for a near-optimal screw system that in the majority of cases is complete overkill.
 
I think I was being called something unpleasant for that kind of resoning :)
 
How much do we want to spend on having great screws so we can avoid wear and tear that eventually makes you have to replace a 10 EUR case after opening it too many times?

After all, while I like the idea of a hardware hacker friendly device a lot, I'm not a hardware hacker myself and I assume that most of the community is not. So even if it only costs 2 EUR extra per Pyra to get extremely wear-resistant screws, I'm not sure if it is worth it -- it may be better to let those who want to do a lot of open/close cycles buy a couple of spare cases, instead of letting everyone pay for a near-optimal screw system that in the majority of cases is complete overkill.
The pandora case survives about three openings before the battery contact compression get problematic. Though my 1 GHz pandora didn't have case parts that fit together when I got it.
 
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How much do we want to spend on having great screws
Screws are literally measured in pennies. Really high quality screws meant for wood and metal might get up to $1 each at retail, contractors and manufacturers buying in bulk get premium discounts. Realistically, for the size and quantity, we're probably looking at about 10 cents per screw at most. I'm pretty sure we can eat the extra $1 it may cost to have high quality screws, even if you never open the case at all.
 
I think I was being called something unpleasant for that kind of reasoning :)
Right, but even from the point of view of a hardware hacker: isn't it more important for hardware hackers that you can buy spare cases easily and relatively cheaply, than that you can have many screw/unscrew cycles on one single case?

If a great screw system is making the case parts more expensive, isn't that worse for hardware hackers in the end? Don't they typically drill holes in cases and stuff like that for their hardware mod projects, risking to ruin the case, so having some spare cases is necessary anyway?

I'm not a hardware hacker myself, so I'm not in a position to make big claims about this, but at least to me it looks like there is some kind of trade-off there.

For non-hardware hackers, excellent screws are essentially a non-feature, because the only potential use they can get out of it is cheaper repairs (since with poor screws, it may become more likely that the case also needs to be replaced during repair of some non-case-related issue). But if the screws can survive a dozen cycles or so, that should be more than enough to cover that.

How much do we want to spend on having great screws
Screws are literally measured in pennies. Really high quality screws meant for wood and metal might get up to $1 each at retail, contractors and manufacturers buying in bulk get premium discounts. Realistically, for the size and quantity, we're probably looking at about 10 cents per screw at most. I'm pretty sure we can eat the extra $1 it may cost to have high quality screws, even if you never open the case at all.
Yes, but I'm not talking about just the screws, I'm talking about the whole screw system, including perhaps metal case inlays or other methods to make sure the case survives many open/close cycles.

As for the screws themselves: I don't think we have any particular need for very high quality screws; I think the important thing is they are standard (so you can easily find replacement screws and a screwdriver that fits), and that they don't rust. Even if the screws that come with the device have a screw head that is not that strong, hardware hackers can just use their own superior screws instead as long as the screws have a standard screw thread. ED could perhaps even sell a "hardware hacker kit" in his shop that includes spare parts and nice expensive screws.
 
I think the important thing is they are standard (so you can easily find replacement screws and a screwdriver that fits), and that they don't rust.
I really just want anything-but-Phillips. There's a lot of standard screws which weren't designed to slip if the screw gets stuck.
 
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