The Espruino now has mounting holes - plenty of them!

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  • 3D picture of E Block R1 from TinkerCad 3D on-line program.

    The Espruino now has mounting holes - plenty of them!
    In fact, there are more holes, in this ABS 3D plastic enclosure, than in a slice of Swiss cheese!

    A 3D "open source" stylish, colored/coloured, ABS, "E_Block" Espruino enclosure with cover was designed with 10 mounting holes!

    Espruino now has many more mounting options (11 versus zero) now include the following:

    1 - 6 internal 4/40 (0.125" or 3.175 mm M3 x 1.5p) mounting holes. (countersunk holes)
    2 - 4 external 4/40 (0.125" or 3.175 mm M3 x 1.5p) mounting holes.
    3 - Foam/3M tape on the back of the enclosure.
    4 - Hot glue on the enclosure back or sides.
    5 - Velcro (industrial) tape on the back of the enclosure.
    6 - Hot glue on the external mounting tabs/holes.
    7 - Tie wrapping the enclosure.
    8 - 4/40 1/16" nylon standoffs with adhesive foam backing for the mounting holes.
    9 - 4/40 metal hex/round standoff(s) for the mounting holes.
    10 - ABS plastic adhesive (Vendors: Loctite/JB Plastic Epoxy for ABS) on back of the enclosure for permanent mounting.
    11 - 1/8" aluminum or plastic rivets can be applied to both the internal and external mounting holes. Be careful when riveting the soft ABS plastic and use backup washers.

    Note A: Need a larger hole size? - just carefully use a hand reamer on the ABS 3D plastic!)

    Note B: You can use the enclosure as a "protective enclosure box" for the Espruino. Just machine/sand/grind off the external mounting tabs.

    To obtain your own E Block for the Espruino, all you need to do is to use the "attached", F R E E industry standard "stl" files and take it down to any "mom and pop" 3D printing service and have it sliced or printed for a "fee". Before you do this, check the text below
    to see if it will fit your needs.

    3D printing tips:
    There are really only two main types of 3D plastic slicer/filament materials ABS or PLA. The petroleum base ABS (better for this application) than the environmentally safe, corn/sugar based, low temperature, better resolution, PLA filament. (Your choice)
    (E Block and Lego blocks are also made out of ABS. Playing with the Espruino is the same as playing with Lego blocks!)
    PLA has a lower melting temperature and if you leave your E Block in a hot vehicle it might warp!

    There are so many 3D filament colors to choose from - just pick any colour. You can even pick "fluorescent" to have your Espruino "glow in the dark". I prefer "black with my Espruino" or maybe fluorescent to match the color of my Espruino when smoking or burning-up. (bit of humour)

    Infill density is what you don't see in a 3D print. It's what is behind the solid looking walls of the enclosure. 0 % is hollow and 100% is solid. In this design, 50% infill density was specified which is good. Having it higher would takes many more hours to print and waste filament resources. In this design, a 3 hour print would almost double to 6 hours if the infill was changed from 50% to 100% !

    Never ever choose a hourly rate for 3D printing and just only pay for the volume. The unit of filament volume is always cm3. The going rate in US is @ $0.25/cm3 ($USD), which is 7 times the cost of 3D slicer filament and all vendors make money but they still have to defray their inital cost for their 3D initial investment which runs into several thousand US dollars. Now days, their same piece of 3D machinery, can be had below $500 ($USD) (examples: XYZ printing - DaVinci 1.0 $499 USD or Ez3D The Phoenix $399) Other 3D printers want $100 "setup fee" just to turn on their machine and they also charge by the hour and by volume! Be extremely careful and do not pay excessive fees just for a piece of printed ABS/PLA 3D plastic!

    We like to be clear. The above two reference 3D printers are only for a price reference only
    and not an endorsement. Both 3D printers have flaws and you need to do thorough research before buying any 3D printer!

    Files attached:
    E_Block_R1.stl volume (cm3): 48.11 @ 0.25 ($USD) = $12.03 or 9.15 euro (1 US = 0.76 euro 3/9/14)
    E_Block_Cover_R1a.stl (optional) volume (cm3): 9.84 @ 0.25 ($USD) = $ 2.46

    3D printing/manufacturing stats (3D machine dependent):
    E_Block_R1 enclosure: 41 grams/16.73 meters of 1.75 mm filament @ 180 min./ 3 hours runtime/printing time (3D machine dependent)
    E_Block_Cover_R1a : 11 grams/04.39 meters of 1.75 mm filament @ 41 min.

    Summary:
    To print out the E Block enclosure, specify the material ABS, your color or the color the vendor has on hand and the infill density of 50%. Hand the "stl" file(s) to your 3D printer and negotiate the fee. The already computed "enclosure" volumes in cm3 are above.

    The finished computed volume in cm3 is for a 100% infill density.
    Since most 3D printing vendors put a default of 50% infill density to save time and material, which makes a "honecomb fill structure" between the surface walls, don't let them charge you full price for the "finished volume" when you are getting 50% less!

    3D E_Block Enclosure Design:

    The E block enclosure was designed to fit the Espruino, have mounting holes, allow for "open front" power and Espruino programming. You have to take the optional lid/cover off for access to the two push buttons for firmware updates. The enclosure cover/lid was only made for the two 20 pin GPIO female headers (0.350" / 9.017 mm or less in height). The horizontal 10 pin GPIO header could not be incorporated, in this design, due to material cover/lid stress. Of course, you could ditch the cover and just only use the protected 3D enclosure. The female header(s) do not fully protrude through the cover due to clearance of the battery connector. This means you will need to attach your wiring harness through the cover first then attach the lid to the Espruino. Due to accuracy/resolutions of different 3D printers, there might be a tight fit of the Espruino in the enclosure channels. Take out your Dremel or miniature rotary tool and grind or sand the ABS for proper clearance. (Do not machine the hard FR4 fiberglass of the Espruino printed circuit board even though the PCB routing clearance could be the source of the problem!)

    This 3D enclosure design incorporates an "open front" for easy access to the battery connector, micro USB connector and the SD/transflash drive. Having an "open front" also provides for easy viewing of the Espruino's three RGB status LEDs.

    Note C: You might have to drill a hole in the E_Block enclosure and lid/cover tab for a very secure lid tie-down. Be sure your mounting hardware does not conflict with the Espruino. Also, just use any plastic epoxy (Loctite/JB Plastic Epoxy) and secure a nut on the enclosure lid tab for easy assembly. Also, you could use Velcro across the lid to hold it in place.

    Note D: The Espruino hortizontal connector GPIO header has 10 pins but in this design only 2 GPIO can be accessed (I2C2 bus). Of course, leave the lid/cover off and there would be no problem. Do not used any Espruino female "stacking header" connectors with this enclosure!

    Note E: When applying female headers to the Espruino, for the first time, make sure on the bottom side when soldering all solder joints are even in height for a level fit into the enclosure. You might have to trim or cut the excess leads.

    Note F: The E Block enclosure was not designed for optional component additions to the Espruino but many of them will fit. Just keep the components below and in between the headers. You will need to make sure your optional components will not conflict with the enclosure.
    If so, you could modify the enclosure to your own needs. (see below)

    Note G: The Espruino mounting in the enslosure, is a "friction/jam fit" and if need be apply a small dap of plastic hot glue to hold it down or just let it float.

    For those hackers, like me, who like to "tinker" and need to modify this design, just go to the "Free" on-line TinkerCad.com and modify or create another design from my open source public design. Just use their extremely easy to use and learn 3D TinkerCad and import my "open source" E_Block_R1 / E_Block_Cover R1 files and tinker away with your heart's desires. Export your design file in the "STL" format and you are ready for another 3D printing. (Search in TinkerCad.com "Gallery" for E_Block_R1 and E_Block_Cover_R1a)

    Whew ... a lot of work for a piece of 3D plastic with holes in it!

    Disclaimer --> This project is "as is!" <--<<<

    End of project ...

    Enjoy / Cheers ...


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  • BTW - also attached is the E Block Cover/Lid

    Update 8/9/14 - adjusted horizontal notch - revision goes to a.


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  • E_Block_Reduced_Cost_R1 ---> 19.014 cm3
    (Use "attached" stl file below for 3D printing)

    This is a new modified E Block design that reduces the cm3 volume from 48.11 cm3 to
    19.014 cm3.
    A 2.53 x reduction in volume should reduce the cost by a factor 253 %.
    19.014 x $0.25 = $4.75 or 3.61 euro (1 US = 0.76 euro 3/9/14)

    Be sure to shop around for the best price for 3D printing. We found many vendors with ridiculous, exorbitant, high prices.

    This is a "bare bones" design without the fancy "bells and whistles" of the E_Block_R1.
    There is no optional top cover.
    There is no external four mounting holes in the enclosure but it still contains the six internal countersunk mounting holes.

    To review this 3D E Block cradle design enclosure, for the Espruino, go to the TinkerCad.com
    website and under "Gallery" search for "E_Block_Reduced_Cost_R1"
    Again, if you need to modify this design ... "just do it"

    Enjoy / Cheers


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  • E_Clips_R1 ----> 0.3809 cm3
    (Use "attached" stl file below for 3D printing)

    E Clip cm3 0.3809 x $.25 = $0.095 or 0.072 euros <--- This cost is shocking!
    Of course, you still have to negotiate for the best and lowest possible fee for 3D printing.

    The lowest cost solution to mechanically hold the Espruino v 1.3 in place. It has a 1/16" / 0.062" or ~1.57 mm notch to grab the side of the printed circuit board. Order as many as you like but you need at least three of them for secure mounting. (2 sides / 1 back)
    Do not use this E Clip anywhere on the front near the USB connector - there are small SMT components positioned in that area!

    Has two 0.125" / 3.175 mm holes for secure mounting.
    E Clip suspends/elevates the Espruino above the surface plane by 0.393622" or 10 mm. and it obstructs nothing.
    The front transflash SD and USB micro connector can be easily accessed using the E Clip.

    3D Printed order suggestion:
    Make the "Infill density % = 100%" for the maximum strength possible.

    To review this 3D E Clip, for the Espruino, go to the TinkerCad.com
    website and under "Gallery" search for "E_Clips_R1"
    Again, if you need to modify this design ... "just do it"

    Enjoy / Cheers


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  • Wow, thanks for posting these up!

    Do you have any pictures of what they're like holding the board when printed?

    Would it be ok if I put the files on this webpage where there are some other 3D printed designs?

  • Do you have any pictures of what they're like holding the board when
    printed?

    Just hot off the 3D printing press...
    The E Block R1 enclosure is on foam nylon 1/8" standoffs for demo purposes.
    Clearances are very tight and there is no need for hot glue to hold the Espruino in its cradle or cage.

    Would it be ok if I put the files on this webpage where there are some
    other 3D printed designs?

    Not quite yet ... The E Block R1 came back today and the Espruino fit was good. We had to
    immediately revise the E Block Cover from "E_Block_Cover_R1" to E_Block_Cover_R1a"
    Wait for the dust to settle. Besides, there is no place for "credits" and links in the folder to
    this forum link to inform the users on what to do when placing their 3D printing order.

    On another note ... The rough looking ABS texture is normal for the infill density of 50%.
    There is a "Acetone 3D ABS vapor treatment" (google for it) that will make it shine like Lego blocks. Also, requiring the low temperature type PLA filament will make the texture look better.

  • For those who want a shiny porcelain finish on their "ABS" only E Block enclosure ...
    Note: Will not work on PLA type filament plastic.
    Note: Do not over do this process for you will melt all the ABS away!

    http://airwolf3d.com/2013/11/26/7-steps-­shiny-finish-on-abs-parts-acetone/

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The Espruino now has mounting holes - plenty of them!

Posted by Avatar for user7114 @user7114

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