Solar powered buttons

I've been playing around with new buttons but from a different angle.

I'm using some stuff called Sculpey to press into the molds. It's not transparent but it does raise some interesting possibilies since it comes in different colors (including 4 glow in the dark colors), is cheap and doesn't have a problem with bubbles.

You can buy it at any craft store (Fimo works too). It doesn't provide the true back lit buttons but it's another option. Just make sure you make your mold out of a silicone rubber that can take the heat (265 F).

I used Smooth-on's Evergreen 40 rubber. It's pours bubble free but has a low melt point (170F which I didn't find out until after I made the mold). If you want to do resin casting, it seems to work well and is a 1 to 1 by volume mix ratio.

Hmm... Interesting...

My only concern would be the "staying power" of the glow. It might be possible to mold this into a thin layer, combine it with backlighting (buttonhack) to constantly "charge" the material.

Yes, it fades fairly quickly. I was thinking about filling a Farnell transparent button with it for the new face. I think it would give an edge lit effect with a glowing center. I've also got some phosphorescent powder that I'm going to try mixing into some silicone that way you get the translucence and the glow.

Have you heard anything from Casting_Fool lately? It'd be nice to have someone with more experience solving this one.

Actually, yes and no. I have not heard a status recently, but Stu sent out a Eutronix newsletter. In it was a statement that he had the documentation for the button kits ready, and that castings would likely be available "soon". I presume that significant progress is being made, but nothing made available yet.

This is cool. Now I need to find some blacklight leds....

Exactly what I was thinking. They'll charge the buttons from behind whenever the empeg is on.

I found some but all of them carry warnings like...

Never look directly into the LED - especially at close range.
Never point the LED at someone's face.
Wear UV filtering glasses/sunglasses.

How bad are these things on your eyes? Would putting them behind the buttons act as a sufficient filter?

http://www.etgtech.com/product_9.html

How bad are these things on your eyes? Would putting them behind the buttons act as a sufficient filter?

Here's an interesting link on UV:

http://wolfstone.halloweenhost.com/TechBase/blttip_BlackLightTips.html

The host is missing for the link to the leds, but just about anything filters uv out. These buttons would fer sure. I'd be sure that they are mega-sheilded from any leakage to your eyes and also from any plastic other than the buttons. Most plastics are not UV stable.

Cool, thanks.

I've got a couple of sources for the LEDs but am not sure they'll work with Stu's button kits. I've pinged Stu for an assist but does anyone else know if these will work?

http://www.led-center.com/products.htm

http://www.roithner-laser.com/LED_diverse.htm

At the second link I spotted no 3 mm UV LEDs, but at the first site they have 3 mm ones WUV303-C395-C(395±5nm) , WUV303-C405(405±5nm).

IIRC, the supply voltage is 5V, so the 3.7V they sport should be OK. You might want a different resistor value than supplied (IIRC 1kOhm) in the resistor pack. I'd get the LEDs, hook one up with wires and trim potentionemeter, and trim until you had the output you wanted with the knobs you're using. Then measure what the pot says and get the closest available resistor pack...

But for the knob you need SMD LEDs, which the second site has (the first hints that all their LEDs aren't in their catalog, so you might want to ask them about SMD LEDs as well).
E1S09-OPOAP-02, 385 nm, 1.7 mW @ 20 mA, SMD, 3.0 x 3.4 mm², 110° viewing angle
looks to be the best match.

/Michael

Mmmm.. which reminds me..

Here's Alvin playing with his Lego (Duplo) set:

Ahh, thank you very much. I'll contact the othe site to see if they have 3mm also.

Those are hi-tech, RTV retaining walls. I only play with bionicles now.

Forgot to say - I think the size of the SMD LEDs vary between some of the kits/boards available - check which size fits the board you have/will get...

/Michael

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I've got a couple of sources for the LEDs but am not sure they'll work with Stu's button kits. I've pinged Stu for an assist but does anyone else know if these will work?

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Hmm, never got anything from you. The UV T1 LEDs should work fine. Their forward voltage is within 1/10 that of the white ones we use. I don't see a link for UV surface mount LEDs in your links. I can probably get them if you need them for the knob board. And as far as that goes, here are the dimension used in the surface mount pads we have on our knob boards:


Stu

I thought I sent an email but thanks for the reply here. If you have a source for either the UV T1 LEDs or the surface mount LEDs, I'll take you up on the offer. I've got an email in to a source in Taiwan and Austria but no response as of yet.

How many do you need? The smaller the quantity, the less cooperative many distributors become. The ones I've found are a little oversized for the knob board, but not too bad. Availability is sketchy, especially on the SMDs, but I think I can get them.

Stu

A minimum would be 4 of the T1s and 4 of the SMD's. Depending on price ($5/range?), probably a max of 10 of the T1s and 10 of the SMDs.

Anyone else interested?

It's not transparent but it does raise some interesting possibilies since it comes in different colors (including 4 glow in the dark colors), is cheap and doesn't have a problem with bubbles.

It looks very similar to the stuff I keep talking about... where it's milky-white translucent so that it diffuses the light. Can you see light through it at all?

Yes you can see light through it but it's not great. I'll take a pic tonight. The also make a translucent clay and fluid but I haven't tried it yet.

I'd love to see if you can mix the translucent stuff with the white stuff. My ideal would be a gray shade that looks similar to the original buttons when unlit, and faintly backlit when the LEDs are on.

ooooh... that would be so sweet. A smoke grey color that slightly glows when backlit. Very nice. me wanty.

Ok I'll give it a try. I'm making a new mold right now so it'll be a week or so. I've got some silicon rubber that I'm going to try soft touch buttons so I'll try to color it also.

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Depending on price ($5/range?)

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Somewhere in there. Maybe a little less.

Edit: I am expecting a call from a distributor regarding the SMD UV LEDs. If there is enough interest, I can already buy the SMD units from another distributor, but only in 100 unit minimums. The T1s I can get in a 25 unit minimum.

Stu

It transmits light more than I thought. I've got a pen flashlight behind the knob so its brighter than it would normally be but it's a softer glow than the pictures show. It don't have the button illumination kit installed yet so it's tough to say.

Gonna cast both Mk2 and Mk2a knobs?

I've got the mold for it but haven't tried it yet. The edges are very thin on that knob. I'll give it a whirl tho.

I'm going to try soft touch buttons

Explain. Do you mean you can create buttons that have that rubberized feel to them? I was just thinking about figuring out how to do that.

couldn't you coat a thin layer of some sort of vulcanizing rubber in the mold, then fill the rest with plastic?? Hm... you'd have to use a hard mold for that though wouldn't you... or do they have rubber molds than are compatible with other types of rubber...

I don't know. Maybe.

The knobs in my new car are rubbery on the surface, but hard underneath and I thought it would be cool to have my empeg's knob be the same. Thinking about new buttons, too, but we'll see about that one.

Regardless, I need to get it installed first.

I'm using a smoothon rubber mold material called Clearflex 50. If you use mold release, you can pull the rubber parts from a rubber mold. See the product sheet for more info.

http://www.smoothon.com/PDF/Clear%20Flex%2050%20&%2095%20Combo.pdf

As to how to do it, Rob S mentioned the idea in Amersfoort and Hugo suggested it here. I've got a set of transparent button from farnell that I am trying to cast around. I say try because this is just theory at this point.

Okay, the UV LEDs are on order. Not the easiest to get, but it's done.

Stu

Impressive work, Mach.

Things hit a bit of a wall here when I got ill for a few months (chlorine gas poisoning, lots of fun), but we're slowly bringing the shop back up to speed. I'm a one-man operation, so when I did the "gas thing" all of our projects fell behind. Which affected our income, etc..

I've got a few days of intense work this weekend and we should be back on schedule with the projects that ended up on hold, like the fascia/buttons. Pending some client's payments that are in the mail, I'll have the materials to pour the first molds end of next week.

I like the smoked idea, and will be trying a few different fillers to test their effect on the clarity of the buttons.

I probably won't be doing any soft-surfaced/hard-center buttons, but for the record, some soft urethane resins will bond permanently to a compatible hard urethane resin. I've done some experiments involving scale WW II tank road wheels that turned out rather well.

My sincere apologies for the long wait. Had to catch my breath... ;O)

(BTW, our website is temporarily unavailable. It'll be back up soon.)

Glad to hear things are looking up for you!

Wow, chlorine, that's nasty! You have my sympathies!

The next time that I help design, build and maintain a water treatment plant, the ventilation system is going to be a used turbine from a 767.

We had a chlorine solution failure that over-taxed the ventilation systen in the building. Over the course of 4-5 months I was getting a daily dose of just enough chlorine gas to affect my lungs, but not knock me out or indicate that anything was wrong in the building.

About the time that I couldn't draw a full breath and my son got tired of my... ah... reduced mental capacity from lack of oxygen, we figured it out and replaced the bad solution with good. I also upgraded the ventilation until we got rid of the balance of the old solution.

The hard part is getting through the slump caused by the loss of time in the shop. Lost time = loss revenue. It's been tight, but it looks as if we'll get through it okay.

Thanks for the encouragement!

Thanks! I'm definitely out of my depth but it gives me something to play around with.

I'm glad to hear you caught the source of your health problems. Please try to stay out of the life threatening gases for a while, huh?

I'll be watching the button thread for more info.

So second mold is finished. I tried a rough run with decorating gel made by Eberhard Faber. Some things worked; some didn't. Here's what I found...

The Farnell buttons embedded in the mold before casting worked well. Use the shortest (16mm). The 19mm give too much of a halo within the buttons.

The decorating gel tears too easy (the 4th button tore apart) but is flexible when it sets up. (Flexible buttons are very cool.) The color is about right for white glow buttons. It's tough to tell in the photos but they have a frosted glass look to them.

I tried another batch with black pigment to attempt the color discussed above but the buttons came out with a purple color and glow with a wine tint.

The mold itself needs work. I'm using a silicon RTV rubber that can take high temperatures. The button tops cast clean but the sides are a ragged. I didn't take into account the farnell buttons blocking the sprue holes.

I also tried some FIMO clay for the knobs but they crumbled when I tried to pull them from the mold. The Sculpey clay seemed to work better.

Hey Alvin,

looking really cool! Keep on trying...

I have the feeling, it's not a long time any more to get coool buttons.

cheers, Thomas

Thanks! I hope so. It's an interesting problem to play with.

For anyone interested, we have a limited supply of UV LEDs on hand at $5 each. PM me for details.

Stu