[Matt]’s been working on a small hombrew MP3 player, and although it’s not much more useful than an iPod Shuffle, sometimes that’s all you need. Besides, it turned out to be a beautiful project, completely custom, and a great example of what a high resolution 3D printer can do with an enclosure design.
Inside Bumpy is an ATMega32u4 with a VS1003 MP3 codec IC. The device is powered by a 1000mAh lithium battery, and the user interface is an exercise in simplicity; a single click/scroll wheel changes the volume, toggles play and pause, and selects the next or previous track. Eight LEDs mounted in the center of the board glow through the case for status, volume, and interface feedback.
By far the most impressive part of Bumpy is the case. It was printed at [Matt]’s place of employment – Formlabs – in white UV curing resin. The pictures show a surface finish that would be difficult to replicated on a squirting plastic style 3D printer, with a textured, bumpy surface that inspired the name.
Not many people can say they made their own MP3 player… PCB design looks very nice and the case is beautiful!
Indeed. My home is also a 3D design and manufacturing company.
Printed standing up those bumps aren’t difficult at all to print with a standard FDM printer. I can’t quite figure out why he decided to tilt the parts the way he did. Looks like a LOT of wasted support material. Then again I’m not very savvy when it comes to those types of printers so I’m sure there’s a reason for it.
I was wondering the same, maybe it’s simply a photo, and not the way he actually printed it.
May be he was trying to minimize the printing area?
But I am not an expert so :P
This makes sense, looking at it, he could’n’t fit the two sides, and this type of 3d printer takes FOREVER, so to save time he probably raised it so he could fit both in 1 day, rather than wait 2 days for two parts.
Some SL 3D printers can make a layer in less than 10 seconds. I’m not sure you can do that with FDM 3D printers…
I printed the case at an angle because completely flat surfaces are easily distorted by the print process — Formlabs recommends printing flat surfaces at a 10 – 20 degree angle (https://support.formlabs.com/entries/23388606-Model-Orientation#angle)
Interesting, had no idea that was an issue. Thanks.
I printed the case at an angle because completely horizontal surfaces are easily distorted by the print process. In the official documentation, Formlabs recommends printing flat surfaces at a 10 – 20 degree angle (https://support.formlabs.com/entries/23388606-Model-Orientation#angle).
I think Formlabs encourages printing parts at an angle to minimise the printing area in an effort to avoid adhesion issues when peeling. People have been complaining about larger prints failing and also unsettling “cracking” sounds during peels on large prints.
oh wow, I had no idea. Makes me wanna stick to ABS and PLA, but then again they’ll never look this good.
Yeah, put me off a bit too… IIRC the issue of larger prints failing is brought up in a Q&A session in this video (46 minutes):
https://www.youtube.com/watch?v=Ypf1qu5o_iY
Adhesion to the bottom of the vat is one of the main problems with bottom-up sla machines I think. And the PDMS non-stick coating needs to be “refreshed” quite often.
Too bad the case is going to hide that pretty PCB!
i loooooooooooooooooove the design – but i would really like to see mp3 player with 18650 swappable battery / and on/off headphone amp for big cans
I wonder if it would be hard to port MP3 libraries to Cortex M3/4 micros that have some DSP instructions. Like Tiva C or STM32F4.
Helix is an open source MP3 decoder that can be put into service for that purpose : https://datatype.helixcommunity.org/Mp3dec
http://hackaday.com/2011/10/18/tiny-mp3-module-is-perfect-for-your-next-project/
That one still relies on a decoder chip!
cool project. I just wondering why to use mp3 and not oggvorbis/flac for an open project. Aren’t there any chips which can do that?
Hello Bryan
I am working on a wet able with a MP3 player and would love to be able to talk to you and have you expertise on this project. Please send you contact for further discussions .
Best regards
Amadou diene
Sorry for the typo I wanted to say wearable.