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 LNBits FOSSA #Bitcoin Lightning ATM build. @Ben Arc  Still waiting for the ESP32 screen u less anyone has a donor ESP32 WT32-SC01 Ref: https://github.com/arcbtc/fossa Next the box. https://i.nostr.build/ZNeiYsx9Z59x3a4K.jpg https://i.nostr.build/iLkhhbVVmBc3HXag.jpg  
 Pretty cool 
 🤩 Can you include/upload the box template to github? 
 I have uploaded the front facia here:

https://github.com/lnbits/fossa/tree/main/3DPrints

It's still a prototype, and I await the screen's delivery. I suspect I need to add more clearance.

The back box is currently being designed; for example, it needs a lockable door.


https://i.nostr.build/see7fl9Z4nRfdAr6.png 
 If you want to try printing and let me know any issues that would be cool ;-) 
 Dude! Nice! Care to share where I would find the STL? 
 Uploaded here: https://github.com/lnbits/fossa/tree/main/3DPrints

I am still prototyping, so feel free to give feedback. 
 Thanks Ben! Not having this was the main reason why I had not completed my unit. Will provide feedback 
 OK, if you're building, you will want some extra parts ordered up.

M4 x 16mm pan head security torx tamper resistant bolts (14mm+ is fine)
These hold the front facia to the back box.
https://www.amazon.co.uk/gp/product/B0BTTRPBQV/

Tamper-proof torx wrench (T20)
To tighten the front facia Torx bolts.
https://www.amazon.co.uk/gp/product/B0D53LNNRW

M4 x 30mm carriage/coach bolts
These are to replace the bolts supplied with the coin acceptor to accommodate the thickness of the facia.
https://www.ebay.co.uk/itm/386550912089?var=653926055961

5.5mm x 2.1mm DC Power Jack Socket Female Panel Mount Connector
This allows the 12V adaptor to plug into the ATM's outside. The box assumes a diameter of 7.7mm (like these).
https://www.amazon.co.uk/dp/B01N3679B8

Rubber feet (D30x22xH15)
If you want to have this one on the table, some rubber feet will go at the bottom of the backbox with an M5 bolt. You can also use adhesive versions. Grooves in the bottom of the box will support up to 30mm in diameter.
https://www.amazon.co.uk/dp/B0CQ23M5Z5

Cabinet draw tubular 16mm lock
This will be mounted on the door. I may do a variation with an electric solenoid that can use a pin from the screen to unlock so keys will not be lost. I will create shims for different-sized locks to work with the door. NB Door design is still pending.
https://www.amazon.co.uk/Litensh-Tubular-Cylinder-Cupboard-Letterbox/dp/B09SHWXWXC/

M15 x 16mm hex socket bolts with M5 nylon nuts
To screw the rubber feet into the back box.
https://www.amazon.co.uk/16mm-Socket-Button-Head-Screws/dp/B09BG8XNM7
https://www.amazon.co.uk/Bolt-Base-Stainless-Insert-Nylock
https://i.nostr.build/aJ3n6egmVCgRFNpR.png

Will also be looking into actual 16-pin connectors and alike for a soldered finish rather than push pins that are more likely to fall out. 
 Oh, and:

Female threaded heat set knurled embedded insert nuts, M4 x 6mm L x 6mm OD
Using a soldering iron, these are heated up and pushed into the back box for better attachment of the facia.
https://www.amazon.co.uk/gp/product/B09MCVW4GQ/

Optional: Adhesive security plate and locking cable
Secure the ATM when desk mounted.
https://www.amazon.co.uk/I3C-Security-Anti-Theft-Hardware-Smartphone/dp/B07FM93JL6 
 I think the facia needs some work, the screen won’t fit! I saw you don’t have the screen yet right? 
 Yeah, not yet! Had an idea - can go off measurements of other cases for that screen. 
 I think the bill acceptor is upside down in your picture 
 Yeah, it is :-) 
 Recon 0.4 to the width and the height would fit OK? That's the extra dimension I have from a case I have found seems to allow (for the inaccuracies in printing basically). 
 It think that would probably work, the USB C port also it pretty tight to the screw hole in the facia. Probably need to print just that part to test 
 Ah, you mean the mounts in the corners? https://m.primal.net/JbHu.png  
 Yep! Since I could not fit it anyway I had a look and I think if it had more tolerance the mount would probably jam the usb c port 
 OK, also reduced the mounts from 6.8 to 6.3mm. Also added more space around the 16-pin connectors. And added cooling to the processor. https://m.primal.net/JbId.png  
 Nice! Yeah probably smart to add some space to the pin connectors. They did not fully line up 
 Did the test print fit ok? Have also made same measurement updates to the facia and a bunch of minor amendments such as more mounting holes to the rear. Will also add LNBits logo etc too soon. 
 Did you see the list if screws and alike needed? 
 Yep! Much of it is already on its way,  the print looks ace. Will send a picture soon.  Will try to print the new screen mount  in the next days 
 Keep me posted. Printing the back-box at the moment which is pretty big. Should be finished by the morning.

I’m assuming you can slip some thin nylon bolts between the layers in the screen and use suitably long bolts to hide the screen in. Although some of the holes may not have enough space behind?

Alternative will be a way to mount the screen from behind the facia with a lip to stop removal. 
 I used a heat gun to heat the printed screen mount so that it became soft and then press fit the PCB / screen inside, I don’t think it will go anywhere now 😂.  If you do this watch out that you don’t overheat 😄 
 Ha ha nice work! 
 Got some pics? :-) 
 What do you think? I learned from BC that it’s also possible to add a thermal printer, that will fit easily I guess.
https://m.primal.net/JcUF.png 
 Epic xxx I’ll add a version that has a space for the thermal printer too. Need to order one myself. Cover plate will have space for LNBits branding. 
 There’s also a plate you can print that goes the coin slot to make it black and match the other components. See “FOSSA ATM Slot Cover” in the repo. 
 Here’s my prototype FOSSA ATM so far. @lnbitsshop @Ben Arc @BlackCoffee #Bitcoin #BuildStr Waiting on the screen to be delivered.
https://m.primal.net/JcYO.jpg 
 Looks incredible. How long did that case take to print?? 
 About 10 to 11 hours 
 I mean for the big part 
 What printer you have? Settings? 
 Moneyprinter 💵 

Setting: infinity ♾️ 
 🤣🤣  
 Missed this one, K1 Max 0.24 for big part 
 On a Prusa MK3S at 0.2mm layer high and SPEED setting, backbox takes 38 hours and front facia takes about 14 hours. Something like Bamboo should be a lot quicker. @Nathan Day?! 
 I'd be terrified of a failure. I'll give it a go though. A couple of rolls of 2kg PLA / PETG I expect?

Also, check your telegram dms. 
 Let me make a minor amendment to the backbox. One of triangular supports pushes the cash acceptor. 
 About half a roll of 1kg at 10% for the backbox (thought it would be more!). 
 As long as the first layer goes down OK you’re normally good. I’m printing this in PETG. Only issue I’ve had before on big printers is the edges lifting. Now have the enclosure for the MK3S+ and not had that issue since.

Will design up a sheet metal backbox design for a more secure version with the front facia rear mounted. 
 That looks awesome! Going to print the black cover plate now 
 The door is now uploaded here: https://github.com/lnbits/fossa

https://m.primal.net/JfVZ.jpg 

You will also need a shim that you can attach to the inside of the box. 
 Starting the printer now! Should be ready in 1 hour ish 
 Pics pls :-) 
 Fits great! Maybe we don’t even need the grip? Can you pull out the door with the key alone?
https://nostrcheck.me/media/c7aa97dce57a6f7fabe0b235172feee864f112b66f8029f1b69b476c0d12c810/1e7b69f8a31e191c184d6cd3831310be236e85f8e4a93dbe2261db29714dc5a8.webp 
 Can do - more about something to hold when placing back. 
 
https://nostrcheck.me/media/c7aa97dce57a6f7fabe0b235172feee864f112b66f8029f1b69b476c0d12c810/1e7b69f8a31e191c184d6cd3831310be236e85f8e4a93dbe2261db29714dc5a8.webp 
 @Fabian pretty weird , in primal this image is loading but in Nostur I get a file not found placeholder image from Nostrcheck server 
 Would love to see a future with loads of small businesses having these next to their checkouts and on @BTCMap.org :-) @Nathan Day 
 So Awesome! When can I get one in Bitcoin Orange? 
 Just doing a few prototype prints then look at making them available. The STLs are available for printing on GitHub if you have a printer and want to try building it. 
 Sounds good. Thanks 
 Next we need a video of it working ;-) 
 Want me still to print the test print? I think you have the screen now right? 
 Just printing it now :-) 
 I hope with a beer on your desk 
 Good plan! 
 Door and lock lever shim are coming along! Did you get your lever lock? https://m.primal.net/JeyP.png  
 Nice! Nope but I think you just made me order one 🫡 
 3mm and 4mm (this is the one I need for my lock) uploaded. 
 OK, the screen fits but still too snug. Gonna make it more secure anyway and make it mountable from the rear. 
 Door test is also printing. 
 I mean even if the pcb would fit , the mount would block the pcb from snapping in 
 If you get the chance, I have added a new screen mount test here: https://github.com/lnbits/fossa/tree/main/3DPrints 
 The back box prototype is now printing. 50 hour print!

https://i.nostr.build/9x1mmkxkFE0XsW6A.png 
 If anyone has a quicker printer than me - feel free to try it out from here:

https://github.com/lnbits/fossa/tree/main/3DPrints 
 The back box is a big print! https://i.nostr.build/XHFb81QNKc59qwmR.jpg