ENDER 3 Control Panel Circuit Cover for TFT35-E3 V3.0 Display

Last crawled date: 4 years, 3 months ago

IMPORTANT, PLEASE NOTE: 06/01/2020:
Thingiverse user biniecki reports that BIGTREETECH HAVE CHANGED THE BOARD DESIGN, and that my case no longer fits the revision.
BigTreeTech have indeed added a riser board to the rear of the main board, immediately behind the rotary encoder, even though BTT haven't yet mentioned it in their listing.
If your TFT35 has this extra board (marked "BTT TFT35-E3 ENC V1.0") attached to it, I recommend the use of Andy1974's design (https://www.thingiverse.com/thing:4091472).
I'll leave this design on Thingiverse for those who wish to use the Sketchup design as a starting point, or for those who just want to point and laugh!
Thanks to biniecki for the heads-up, and further thanks to user JDPenney for letting me know about the two other designs (and for helping me with my firmware!)
Update 11/12/2019: Added a variant permitting access to all 3 EXP ports for those needing to use two ribbon cables. Many thanks to Thingiverse user 5bites for alerting me to the need for this.
I upgraded to the rather nice BigTreeTech TFT35-E3 control unit - https://www.biqu.equipment/collections/lcd/products/btt-tft35-e3-v3-0-display-touch-screen-two-working-modes . But then I found that my previous circuit board cover didn't fit (thing 2858209 by Rocco81-92).
I couldn't find any modified versions on Thingiverse. Probably because (at the time of writing) it's a relatively new design and all the truly talented people haven't got around to it yet. So, despite my obvious lack of talent, I was obliged set about drawing up my own.
It's inspired by Rocco's original, but is a complete new ground-up design. I started from the circuit board specs on the BIQU page to get the fixing holes in the right place, and applied my trusty (some say rusty) vernier calipers for the port locations.
It took me several prints to finally get one that fitted - although there is still room for improvement here and there. The first print was my biggest blunder: as you can see in the bonus picture, I placed the top ribbon cable ports on the wrong side! D'oh!
I wanted to have recessed screw heads. But as I draughted it up it quickly became apparent that the multiple port openings limited the space available for such niceties. Thankfully, the screws are on the underside when it's fitted, so it's not really a problem. Speaking of screws, you'll need longer ones: The top two need to be 20mm, and the lower two need to be 15mm.
I had hoped to print it without supports. But the slope on the case means that the printer doesn't bridge the side ports in one go. That, combined with the thin walls of the case, causes a very unsightly result. So I used Cura's experimental tree-support to see what difference it made. I'd never tried it before, but I was pleased with the results - Although I'm sure normal support will do the job just as well, and custom support would be better still.
Design tweaks I would consider if I were printing another? I'd consider increasing the depth of the case so that the entire USB port is enclosed, and I'd definitely open the SD card port about 2mm towards the PCB. It works fine, but the card does rub on the edge as you push it in. I could attack it with a file but, thanks to Octoprint, the amount of times I actually use an SD card on my printer could be counted on the fingers of a leper's left hand.
Thoughts on the BigTreeTech TFT35-E3 V3.0.
Although I am pleased with the panel, I was disappointed to find the display screen doesn't quite line up with the aperture on my Ender 3's mounting plate. The display is offset towards the left edge, which is distracting enough. But you can also see some of the conductive traces for the screen connections on the right edge, and it looks a bit of a bodge (I'd be interested to know if they are all like that, so let me know in the comments).
Don't get me wrong; they've made a great board, at an amazing price, and I have no doubt that designing it to fit it into the original footprint was quite a challenge for them. But it still sets my teeth on edge when I see it.
I hope to update the firmware for more colourful icons. But I'm still very much a beginner with that stuff and, despite attempt after attempt, I have yet to get anything to compile into a .bin file.
That's yer lot. And, as badly translated instructions might well say:
Many printings of happiness to you all.