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[on:]

Hi

I have one of these that I thought I'd donate to a more permanent fixture.  Mine is a GE Tech (http://www.geeetech.com/arduino-lcd-1602-keypad-shield-p-251.html) brand, but the same design also comes from many manufacturers inc Nuelectronics and others.

What I've found is the buttons are located so low when you mount the screen to the inside of an enclosure they're a long way away from the top.  Even if you removed all the headers on the top of the board it looks like they'd still be around 5mm inside the enclosure (could poke them through a hole with a biro, but that's not ideal for this situation & project).

I've been trying to find button caps to extend them up through the enclosure top, but because they're mounted so close to each other, the ones I've found so far are either too short (don't reach out of the enclosure) or too wide (can't fit them on because of adjacent buttons).

Has anyone found a way to set one of these permanently in a project enclosure such that the buttons were accessible?  I see other keypad shields like the Freetronics one the buttons are taller and would avoid this challenge, but was hoping to use this one if possible.

Thanks
Geoff

[Reply #1 on:]

I've got appropriate buttons and caps for my serial LCD keypad panels:

http://liudr.wordpress.com/2011/12/03/phi-panel-face-plates/

The problem of long button shaft is that if you don't mount them, the long shafts are shaky and impossible to press. You will have to mount them.

An alternative is to use a membrane matrix keypad, which has adhesive to stick to a surface. You can use a serial LCD keypad backpack:

http://liudr.wordpress.com/2011/11/21/serial-lcd-backpack/

[Reply #2 on:]

I've got appropriate buttons and caps for my serial LCD keypad panels:

http://liudr.wordpress.com/2011/12/03/phi-panel-face-plates/

Thanks for your reply.  I don't see my particular keypad shield being used there - can you recommend the caps to use for the Geeetech shield?  I do have other shields, including an I2C one but was hoping to use this specific shield in an enclosure.

If you can help me with the extended button caps I'll be happy to buy them off you if that's what you do also, cheers ! Geoff

[Reply #3 on:]

The part numbers from digikey.com for the buttons and their caps are on the bottom of the blog post. You will need to see if the distributor digikey does business in Australia. I only have enough for my two prototypes and a few extra. I first tried to but some off ebay and I got 100 of them with caps. Too bad they are not tall enough even for 16X2 displays. Can't find the link but if you see something on ebay and want me to look at them just post the link.

[Reply #4 on:]

Thanks again, those would be ideal.  5mm wide means they will fit just over the buttons and 9mm tall will poke out the top of the enclosure just great.  These are the first I've seen that would work - awesome!

In other good news is Digi-Key do ship to Australia, but that's where it comes unstuck.  It's $34 for delivery (unless I buy $200+ which is a lot of caps !) so my little $2.56 (even when I added more in for extras!) soon blows out.  I've setup an eBay alert, but hopefully I'll find someone locally who stocks them to avoid such a major delivery hit.

Thanks again, Geoff

[Reply #5 on:]

I have a few spares I can mail you at fair price. Shipping air mail is not expensive. As you noticed I sell stuff (mainly on inmojo.com). I shipped many times to Australia. What I have are buttons and black and red caps. Let me know.

[Reply #6 on:]

Geoff,
Take a look at Tayda. You can get new switches with tall (up to 9.5mm) buttons for $0.04 USD.
It may be easier/cheaper to replace the actual switches.
http://www.taydaelectronics.com/electromechanical/switches-key-pad.html

They ship to Australia.

I've ordered from Tayda several times. They are great for small orders.
I've ordered shift registers, LEDs, caps, resistors, temp ICs, I2c clock chips, resonators, crystals, etc....

Their prices are great for what they have and their shipping is really inexpensive as well.
Takes anywhere from 1-3 weeks for delivery, with most of my orders getting
here to the USA in about 10-12 days. 1 order came in less than 1 week.


--- bill

[Reply #7 on:]

Thanks Bill

I actually ordered some tall buttons from little bird electronics to do just this.  Tayda are great, but to get them for the weekend I needed to buy locally. 

This sure has been a learning experience.  When getting one of these shields next time I'll know there's some customisation needed to use them in a permanent situation.

Cheers, Geoff

[Reply #8 on:]

Thanks Bill

I actually ordered some tall buttons from little bird electronics to do just this.  Tayda are great, but to get them for the weekend I needed to buy locally. 

This sure has been a learning experience.  When getting one of these shields next time I'll know there's some customisation needed to use them in a permanent situation.

Cheers, Geoff

Geoff, good to hear you found a solution. Just get some soldering braid ready to take the original buttons off the board. I remember that Si once compared two LCD shields (unfortunately neither is mine). The higher end shield is well made for mounting. The LCD is recessed. You probably just have to cover the shield with a face plate.

[Reply #9 on:]

Can I bump this please?  I never heard how it turned out, and I don't think the measurements are correct for a Sainsmart.

I've measured the distance from the pcb under the switch to the top of the LCD and I think a 13mm switch is needed, like this one: http://www.ebay.co.uk/itm/100-Pcs-6-x-6mm-x-13mm-PCB-Momentary-Tactile-Tact-Push-Button-Switch-4-Pin-DIP-/290822346269?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item43b65cd61d

I took the preceding to mean that the original buttons would need to be desoldered and replaced.  Have I got that right?


Thanks

Brian Williams

[Reply #10 on:]

Hi Brian

Apologies I probably should have posted when this was finalised.  It turned out perfectly.  Unfortunately the project itself is mounted in my father's boat and since it was a surprise gift it appears I didn't take/keep progress photos to attach here, but can step you through the experience.

The original switches were de-soldered and replaced as you suggest.  This was time consuming but not difficult.  On the board I had there were surface mount components under the switches in between their legs so it was a case of firstly getting the bulk of the solder off with a sucker and some braid, but that left them still stuck so it required  heating the legs from one side and lifting from the other with pliers rather then levering them out and risk damaging those.  The bare holes could then be cleaned up from the component side with braid.  The replacements went in with ease and poke through drilled holes in the enclosure quite neatly.  To drill the holes I made a template after the new switches were in place, with holes poked in cardboard, then marked out where to drill with a sharpie using that template.  I mounted the shield to the enclosure using M3 screws through the holes on the LCD board which extend through the shield to make that possible, then pressed the Arduino into the regular headers from behind then drowned it all in hot glue to try to make it a little more rugged.  My enclosure is mounted vertically, so I thought that should be okay.  It went into the catamaran April 2012 and regular sailing with this mounted to a bulkhead has proven that to be the case, at least to date.

I did make one terrible mistake that I'll call out in the unlikely event someone else on the planet has the same bad idea.  As part of the "ruggedisation" I initially masked the switches and sprayed the whole thing with circuit board lacquer.  As it dries this stuff spreads out, and got under the masking tape and into the new switches, locking them solid.  I used a full can of board cleaner (and what seemed an eternity of washing) to get the lacquer out of the switches and they've worked fine since, but it's a lesson learned.
 
It's disappointing that every LCD shield I've seen since also has this limitation but if they came out with the taller switches they'd be a bit goofy to use when there is no enclosure so there's a case to be made both ways I suspect

Cheers & good luck with yours, Geoff

[Reply #11 on:]

Thanks Geoff!  Wow, what an experience!.  Wouldn't it be wonderful if these jokers sold the boards with the switches unpopulated?  Maybe I'll suggest it to them, but I don't suppose anything will come of it.

It's surprising that most people seem to be happy to use an arduino lash up - at least I assume so - it is aimed at non-professionals, but there is a considerable dearth of enclosures!

Cheers!

Brian

[Reply #12 on:]

Geoff,

Great post! Since a simple button only costs a few cents (in US) but a button with the proper plunger (actuator) for a cap costs ten times more (digikey), I would imagine most LCD shields are made with the cheaper ones. Their purposes are more academic than practical

[Reply #13 on:]

Since a simple button only costs a few cents (in US) but a button with the proper plunger (actuator) for a cap costs ten times more (digikey), I would imagine most LCD shields are made with the cheaper ones.

I have subsequently bought a stack of every length that Tayda stocks, but the reality is since this project I've opted to avoid shields and run with an independent display with switches mounted through the enclosure just because it's so much easier, more flexible for the layout, and of course you can avoid trapping the Arduino and run with a cheaper board with an ATmega on it too.

Their purposes are more academic than practical

Unfortunately that bit is clear.  It's not just these LCD shields either.  Since moving to bare ATmegas and ATtinies for the final versions of project I have found a lot of display modules have their cable headers on the top side which means they need to be moved to the underside to use an enclosure.  There sure must be a lot of naked projects out there 

Geoff

[Reply #14 on:]

It's hard to prototype a project and also make nice enclosure. Afterall most people are one-man/woman team. I've also seen nicely enclosured projects. It takes money and time.