Tunes With Fire

 

One thing that I've noticed in recent times is that there are a lot of electronic gizmos out there that try to jam a lot of gimmicks into a single device.  A lot of those gimmicks I find to be a bit on the tacky side and really don't add any real improvement on the prime purpose of the device. 

I think a lot of that stems back to my university days when I took a course on human interface design (granted it's a bit of an obscure subject, but I did find pretty fascinating). In broad strokes, the main take away I took from the course was that more the "stuff" you cram into something, the more unusable it becomes for a human to operates it. Back in the day, the prime suspect of this crime was the lowly clock radio that tended to have many, many buttons that control things that aren't related to the function of keeping time and waking you up. Sadly, considering that I still have difficulty in finding the snooze button in the morning, this is still very true today. 

So it's safe to say, I don't tend to pay much attention to the noise that emanates from the electronics section of your typical discount department store, but for some strange reason, this caught my eye. 

Fireplace Bluetooth Speaker

On the surface it's basically just another Bluetooth speaker, but what really caught my attention was the "fireplace" feature - yes, another gimmick, but I was actually always a bit curious on how the fire place effect was accomplished, considering that those electric fireplaces you find in homes are a popular item these days, I always wondered how this effect was done and I always wanted to try and recreate that effect on a future project.

So, I popped it into the cart and brought it home. 

Box Contents

Getting it home and opening up the box I found the usual stuff that you would expect (Aux and USB cables, a small manual and the speaker itself). The speaker appears to be made of the sort of cheap plastic that I would would fully expect from something like this. 

 Flipping over the back showed the specs of the unit

Speaker Specifications

Looking at the back of the speaker, I confirmed the suspected country of origin, along with a good assortment of certification labels. But one thing that did leap out at me was the power output of the speaker.  Five watts is actually pretty impressive for something like this, whether that it is accurate we won't be able to confirm until we get inside. 

We got this far, how does it sound?  How about does the "fire place" look? 

On the whole it's OK - I wasn't keen on it being defaulted at full volume on start up, but it's about what I would have expected for an inexpensive Bluetooth speaker, but that wasn't what I bought the speaker for.  The fire effect is basically what I was looking for and definitely looks like what an electrical fireplace would look like. 

So, let's open the hood and take a look inside. 

Opening the Hood

My goal with this exercise is to not destroy the speaker, but rather just to take a look to see how it was put together. 

Off the bat, I'm actually pretty impressed on the design of this thing.  Normally I would have expected the back to be glued in place, requiring a "cut job" (and wrecking my goal of not destroying the thing), or one of those proprietary screws for which no screw driver exists. Instead the back was secured with some good old Philips screws. 

Philips screws!

Once the screws were removed the back was easily opened to expose its secrets.

The secrets within

The first thing I noticed that the speaker was stamped as a 5 watt speaker, so that's a good start 

5 Watt Speaker

Next I also noticed that the front of the speaker was basically a translucent piece of orange acrylic that was textured, most likely used to help with the flame illusion. 

Orange Acrylic

At the bottom of the speaker, there was an opening in the acrylic with a series of orange LED's that were of the steady burn variety (personally I was kind of expecting them to flicker since I know you can get LED's that simulate a  candle/flame effect).

Orange LEDs

Now what really struck me was that the flame effect was actually accomplished by a fairly simple mechanical means in the form of an electric motor that was geared to turn at a slow speed. The motor itself was connected to a shaft on which had what I can only describe as shredded tinfoil attached to it.

"Shredded Tinfoil"

The flame effect was accomplished when the motor spun the tinfoil, which in turn reflected the light from the LED's casting the light on the back of the acrylic sheet

That basically explained how we get "fire" and I have pretty good reason to assume that this is also the same approach that's used in those home fireplaces. 

With that sorted out, I took a look at the brains of the operation. 

Bluetooth Speaker Circuit

At first glance, it's a pretty basic circuit board and it's got the type of features that I would expect including a SD card slot, power switch and the standard USB and aux ports.   

One thing that really impressed me though was that the wiring connections were connected by sockets on to the circuit board, which actually makes any future repairs or upgrades very easy since it's literally a plug and play solution. Usually in something made at this particular price point, I would have fully expected the wiring to be directly soldered. 

At a high level, it looks like everything is being run by 4 chips. To a get a better sense on how things were put together, I took a look at the individual chips to see what they did. 

Basically each chip handled one key function of the speaker. 

The main chip in the board is the brain that reads and decodes the Bluetooth signal.

Bluetooth Chip

Another chip drives the audio output to the speaker, looking up the specs on this chip indicated that it was rated for 5 watts output - so the speaker is really and truly putting out 5 watts of power, so I was quite pleased to see that the manufacturer was not misleading us.

 

Audio Amplifier Chip

 Of course we need a voltage regulator to make sure nothing bad happens to the various electronic bits. We don't want to release any magic smoke after all. 

Voltage Regulator

And of course we want to make sure that we can keep the lithium battery properly charged to make sure that the fire in the speaker stays fake.

Lithium Battery Charger Chip

So it is really a pretty simple circuit which makes sense. but like I said earlier I did notice that there are some really nice touches in the overall design that would make this speaker pretty easy to hack into something else.  

But for now I carefully put things back together and played some tunes. 

With that, a purely impulse buy became a learning experience wrapped up in something that I could modify into something different if I ever get tired of listening to tunes. 

By the way - the song I played is "Scarlet Fire" by Otis McDonald  - Thanks to DankPods to putting him on my radar (though I didn't blow up my speaker like he typically does!)    

Engraving Glass With A Diode Laser

 

Engraving a Mug

As I may have mentioned in the past, I've gotten fairly heavy into the laser engraving world which has morphed into a nice little side hustle for me

As with any business, the key to success is to keep growing your product lines, giving your customers a wide variety of products to choose from. 

I've had some pretty good success in providing a wide selection of wall hangings and custom signs with my ORTUR engraver, but I was starting to feel a bit pigeon holed of being a "sign guy" and was starting to feel a little creatively limited.  

About a year ago I came across a Facebook Market place ad for another ORTUR engraver that was available locally and at a reasonable price. Since I was wanting to have another engraver to potentially increase my productivity I decided to jump on it. 

Once I finally collected my new acquisition, I noticed that I also acquired a few other goodies as part of the deal, including a  rotary roller accessory which gave me the ability to engrave cylindrical objects. 

This opened a whole new world of opportunity for me to explore. I played with my new tool, trying it out on round wooden items like pieces of dowels and rejects from my lathe until I got to the point that I was pretty comfortable on how to properly engrave round things. 

Excited about my new found skill, I wanted to use it to do something more useful. Obviously I can use it to engrave things that I produced on my lathe, but I did want to see what else I could do with it.    

The obvious item that came to mind was glass drinkware - This was something I could easily get an almost infinite supply for very little money.  The idea of being able to sell them as customized engraved items was also pretty appealing.   

An Unblemished Mug

My initial experiments were a little disappointing. First off I discovered that most people engrave glass with a CO2 laser, not with the LED Diode laser that I had. The main reason for this is that a CO2 and a Diode laser work on different parts of the light spectrum. Effectively, the light from my diode laser, because of the particular wavelength that it used, was just passing through the glass as if it was air. 

Doing some experimenting, and after a few donations of my rejects to the local thrift store (they were still perfectly good drinking glasses, they were just a little "unique" - no sense in having them go to waste), I came upon a process that let me reliably engrave glass with a diode laser. 

How To Do It

Painting

The trick is to put on a thin coating of black acrylic paint on the area of the drinkware that you want to engrave. Acrylic is the paint of choice since it is primarily water based, hence would make removing the paint later fairly easy. Acrylic paint is also pretty easy to find since you can find it at any place that sells craft supplies.  

I had also discovered that the paint needed to be a matte (or similarly dull) finish since anything that had a gloss to it tended to reflect the laser beam, greatly reducing the effectiveness of the laser.  

This in turn created another problem. I found that for whatever reason, matte black acrylic paint didn't really adhere properly to glass, resulting in the paint flaking off when it dried. Strangely enough, gloss paint didn't seem to have that problem. 

Because of that, I ended up using a 2 coat paint process to prepare the drinkware for engraving. 

First I applied an thin, even coat (this is important since I found that a thick or uneven coat created spotty results on the engraving) of black gloss paint on the glass surface that I wanted to engrave

Glass Acrylic Paint

Applying a thin coat

I found that using a small roller brush provided the best coverage.

Once the first coat had dried I then applied a second coat of paint, but this time using a matte black paint. Again making sure that the coat was thin and even. 

Matte Black Paint

Getting ready to paint

Painting the matte black paint

Once that coat is dry I now had a glass cup prepped for engraving

Ready to Engrave

Next step is to set up my laser software for engraving. 

When engraving anything cylindrical, I discovered that I needed to set my image to a 90 degree angle and mirror reverse the image - otherwise result would be something that was both sideways and backwards - Like I said, the local thrift store has some unique looking drinking glasses on the shelf at the moment due to me finding out about this. 

Setting the image

Setting the image

Once I got the orientation correct, I then adjusted the image size, engraving speed and laser power. 

Of course the size needs to reflect the area that I want to put the image on, but the key settings here are the laser strength and the speed. In these case, I need the laser as strong as possible, moving as slowly as possible. 

Setting size, speed and power

Once things are set, it's time to engrave. 

Engraving

Once the engraver is finished, you would get this as a result

Finished Engraving

The only remaining thing to to is to clean the paint off. This is just a simple matter of using soap, water, and a little bit of elbow grease. 

Clean Up

Scrubbing

In the end you get a nicely engraved mug (in this case) ready for a hot cup of Joe.

Ready to drink

Now, if you can excuse me, I need to go put the kettle on....