Led ring on a glue gun, help needed. Moderators: adafruit_support_bill, adafruit

[TruckMechanic]

Hi, I'm a mechanic and I would like to improve my electric glue gun. I'm thinking of installing a led ring around the nozzle of the gun to get better visibility when applying black glue on black surfaces.
The gun has a 18V battery but I'm not planning to use this as a power-source straight away. I want to test the lighting first and if it works good I consider installing a buck converter. My plan is to use a small USB powerbank to start with. The whole system has to be as light and compact as possible since the gun is already pretty heavy. Also I need some sort of quick disconnect between the Led ring and the rest of the system, I'm not sure which connector I should use. I have to disconnect it every time I use it.

I've been doing some research, but I got lost in all the possibilities along the way.
Here's what I've come up with so far:
The Neopixel 16 RGB ring would fit perfectly around the nozzle. I don't really need the colors, but if my glue gun can perform some discrete disco light-show it sure can put some sparks in the work :-) I know the RGBW ring would be better, but where I live it's hard to lay my hands on and it's more expensive. Considering the fact it might get some PU-glue on it, the cheaper the ring the better. My only concern is if I can get some sort of "decent" white light from the RGB ring. It doesn't have to be perfect white light, just something I can work with.
Next thing I'm confused about is the controller. I was thinking to use the 5V Trinket (1501), but I'm not sure if this is the right choice. I want it to be as compact as possible, not to get in my way when using it. I only need white light and maybe a cool startup light-show. I'm not a coding expert by far, so the easier the better.
It would also be nice to have an on/off switch with the possibility to toggle between various light sequences, but I'm not sure which switch to use and if/how this would be possible with a small controller.

The main goal is to have better visibility when applying glue. Extra "sparks" are cool and very welcome, but the whole system has to be light, simple and easy to work with. I have plenty tools available and have some experience in electrical work, however I'm a complete novice with prototyping and coding.

Can you guys help me out? All your thoughts and advice are more then welcome. I'll try to post some pics in the next couple of days so you can get a better idea of what I need.
Thanks in advance :-)

[DanGR]

Hi I am a retired Marine Engineer so basically a bigger truck with a motel attached.

The smallest board the QT Py is more than capable for this project.
https://www.adafruit.com/product/4600
https://learn.adafruit.com/adafruit-qt-py

They are out of stock now but a Seeeduino XIAO would also work.
https://wiki.seeedstudio.com/Seeeduino- ... uitPython/

The best code for ease of programming is Circuit Python which is why I linked you to the Circuit Python page of the Seeeduino XIAO

The first step should get the light working then add buttons and sparkle. The cable that is used for this type of work is the JST PH. Here is a link to the JST PH 3-pin selection in the shop.
https://www.adafruit.com/?q=jst+ph+3-pin&sort=BestMatch

The second page has a 3-pin Molex PicoBlade cable set that would also work.

I think the RGB would work fine.

I will get back to you about the switches, I want to test the code on another board so I am sure that my answer is correct. I am also learning so I pick the questions I know I can answer because trying to explain this stuff makes me understand it better.

This sounds like a fun build and pictures would be interesting to see

Dan

[DanGR]

I was thinking tactile switch buttons that can control the board with code, but they are on the small size and if you are wearing gloves they might be difficult to use. A better choice might be an off on push button https://www.adafruit.com/product/3870 this could switch the power like a flashlight. A second one could be used to change the mode or a simple SPDT slide switch could be used to change mode https://www.adafruit.com/product/805

Dan

[TruckMechanic]

Thanks for the info. It's a great help and much appreciated.

As promised here are some pics of the gun I'm using.

141678721_438190410783280_4143066064267284844_n.jpg (111.28 KiB) Viewed 321 times

It's a 2 component gun and the mechanism is pretty complicated. It's a very expensive device (luckily I'm not paying) which is why I first want to try a system with a USB powerbank before getting power from the battery.
The front of the gun comes apart in two pieces, which is why I need a decent connector. I have to unplug the lights every time I use it.

140834324_433693344646360_3295410490561717341_n.jpg (57.41 KiB) Viewed 321 times

As you can see, the nozzle I'm using is pretty short. I also use a longer nozzle from time to time, but the short one is my primary nozzle.

141258873_188391516348677_895337628930264880_n.jpg (69.83 KiB) Viewed 321 times

[TruckMechanic]

The Neopixel 16 ring would fit perfectly on the gun. The 24 version would be just a bit to big, it's crucial the hardware doesn't restrict the use of the gun in any way.

140976416_1042113412962640_5203471250053608857_n.jpg (77.14 KiB) Viewed 321 times

141274776_339665413758857_4326329433475114744_n.jpg (75.19 KiB) Viewed 321 times

140636740_1069484746849673_3639916767540459016_n.jpg (75.05 KiB) Viewed 321 times

[TruckMechanic]

The QT Py is hard to get over here, but I did find a supplier for the Seeduino Xiao. They also have the RGBW version of the Neopixel ring and it's cheap :-) I guess I can get more light if I combine the white led's with the "rgb white"?
As for a connector, would a stereo mini jack be an option? I know the Neopixel requires 3 wires, but I'm not sure if the signal flow would be ok.
Can I power the led ring straight true the board via USB, or do I have to make a separate power line straight from the powerbank?

As you can see in the pics, glue gets on to the gun from time to time. Mainly when my colleagues use my gun and don't clean it :-( I know I can use it without getting glue allover the place, but sometimes things get dirty. I'm gonna order some spare parts for my gun, so I can have my own clean front parts, and keep the dirty one around for less tidier coworkers.
In the future I plan to place a buck converter inside the gun and maybe integrate the controller on the inside as well. But only after I made sure the led's are a bonus. If they tamper the use of the gun, my daughter will have some shiny lights for here doll house :-)

[DanGR]

More lights is always good in my book. Yes the stereo mini jack would work for the 3 wire connection. This whole thing can be powered by the usb. You could eliminate the connector if you glued a rubberized magnet to the bottom of the ring. This could be cut into segments to allow the wires to pass and a steel ring or another section of rubberized magnet attached to the glue gun.

Now the wires can be directly soldered to the control board and it can attach to the side of the gun with magnets and the usb acts as a power switch. This would prove a working concept.

The fancy version can be built on a solderless bread board for testing then moved to proto board. I think this one would be large enough for the project. https://www.adafruit.com/product/1214

Here is a QT Py with headers on that proto board

2021-01-21 12.57.11-1.jpg (469.07 KiB) Viewed 304 times

Dan

[TruckMechanic]

Thanks for the input.
I didn't quite get it at first what you meant with the magnets and the wires, but I figured it out in the end. Getting up at 4am all week is not without consequences :-)
Although the magnets are a good idea, I won't be doing this. When applying glue I got my hand around the front of the gun, I don't want anything in the way. I also want to keep the board out of the way of the glue. The cable can run on top of the gun, it's the only place it's out of the way.
Once I know the systems works fine for me, the plan is to build an enclosure to make it more durable. Maybe use some velcro to mount it to the top of the gun and make it removable.

How hot will the ring run at full power? It doesn't have to light up very long. The open time of the glue is only about 10 minutes, so I have to work pretty fast. I'm asking this because I'm looking at options to mount the led ring on to the red ring of the gun. I was thinking to maybe use hotglue, we got plenty of that for removing dents in bodywork. Double sided tape is another option. I just have to make sure the ring doesn't detach in the middle of the job.

I just checked the powerbank I want to use. It's a 2200mAh version, I guess that's more then plenty to power the system. It weighs 57g so it's pretty light.

I'm still not sure about the use of a switch to add some sparks. Maybe I'll just stick with a cool startup sequence, I got time for this, as I have to apply some sacrificial glue on a piece of cardboard first to get the mixture going and then get to the exact position to start gluing.

[DanGR]

The only RGBW device I had to test was this one.
https://www.adafruit.com/product/2860

I ran it full out for about 30 minutes and it got very warm but not too hot to touch so hot glue should be fine. I am not much of a glue guy so I have no real idea about hot glue failure temperature.

Yes, you could do a fancy sparkle pattern for the startup then go full out. You could even time the full out to shut off after your 10 minute working time. This whole code could be run every time you push a simple button switch.

One like this has a nice long button that could be soldered to the proto board and stick out of a hole in the case.
https://www.adafruit.com/product/1490

It might have been simpler to draw a sketch of the magnetic ring I was describing.

I have a little concern about the wires connected to the ring. It would be best to use a cable with a jacket for industrial application the weak point is where the cable comes out of the jacket and attaches to the three points on the ring. The wires could be glued to the outside edge of the ring to the point where they go to the solder junction but the cable jacket has to be securely fastened to the ring or the red part of the glue gun.

This has given me a good idea about putting a QT Py in an Altoids box with a bunch of blinky lights.

Dan

[TruckMechanic]

I'm having problems sourcing materials. I thought I had a good supplier, but it turns out Mouser is only a great supplier for business clients. For ordinary clients 20€ shipping for 15€ material plus custom fees and VAT is pretty ridiculous.
I've been searching the web for 2 days to find a web shop with reasonable shipping rates, carrying the parts I need, in the EU. It's no success yet. I did send an email to my regular local electronics shop to check if they can order parts from Adafruit or Seeed Studios, still waiting for a reply. Most of the time I can order either the LED-ring or the controller, but never both. I'm not willing to order in different shops as this makes parts twice as expensive.

Are there any alternatives for controllers for Neopixels? I consider buying the RGB ring instead of the RGBW ring. I've been looking for alternative controllers, but I got lost along the way. I see many 3V controllers, but the Neopixel ring requires 5V.
I've been looking at the MetroMini 328 5V and several Arduino versions. But I'm not sure which I'm able to program for RGB or RGBW devices...

[DanGR]

I think the simplest code to use is Circuit Python. Here is the list of all the boards that are supported by CP.
https://circuitpython.org/downloads

Any of the small M0 boards will work for this application.

Dan

[TruckMechanic]

Good news,

I was able to order the parts I wanted at a local electronics store, at a decent price. Now I only have to wait 5-10 working days.
I ordered the RGBW 16 ring and the Seeeduino which seems perfect for this project. It's cheap, very compact and I love the fact it has no reset button. I know for sure my coworkers can not resist the urge to push every button they see :-)

[DanGR]

I see many 3V controllers, but the Neopixel ring requires 5V.

I did not answer this part. Yes they are for the most part 5V devices but some take a higher voltage.

The rings will be getting 5V from the USB but the data signal is only 3.3V. This will work for the Adafriuit neopixel rings and some others I have tried. Here is a thread with a photo showing how I wired a QT Py for a tree decoration. viewtopic.php?f=58&t=173807 I powered two of the 12 pixel rings and two of the 7 pixel jewels wired back to back. So I know those products will work with the 3.3V data signal. The RGBW test I made was done with the same controller.

The code for the sparkle start can use any of the basic animations found in this tutorial.
https://learn.adafruit.com/qt-py-and-neopixel-leds

Dan

[TruckMechanic]

I'm waiting for parts, but I'm still thinking about a decent connector. I was first thinking about stereo jack, but my brother had his concerns about short circuits while plugging/unplugging this type of connector.
I'm now leaning towards mini-DIN 4 pin. I can't source the 3 pin version but 4 pin will do. I think this type of connector would rule out the short circuit concern.

Another thing I'm not sure about is wire thickness. I've been doing some research but I can't figure out what the minimum requirement is for this project. The cable length will be only about 20cm max, so unless I make a spiral cable, voltage drop will be no issue. If I use the led ring at a maximum I will draw about 960mA according to Adafruit's formula for Neopixels. I'm not sure I will need this amount of power, but still I don't want to fry something :-)

[DanGR]

The DIN 4 pin connector is a bit bulky but they are nice connectors. I could not find a DIN 3 pin set either.

Here is a calculator for DC current wire size that worked for the numbers you listed. I just used 1 amp to round things up.
https://www.solar-wind.co.uk/info/dc-ca ... calculator

Dan