Upgrading Longer LK5 Pro with BTT SKR mini E3 V3 & Pi2 v1.0.1

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Thank you in advance for helping a neophyte in the printing world. I have been printing with a Prusa until a few years ago I got fed up with constant repairs. Last year I found the Longer LK5 Pro and bought it. I used it for 6 months while researching how to upgrade it for faster, smoother and quieter printing. I tore it down 3 months ago and can’t get it working. I hope you have the time and the inclination to help. I would be eternally grateful.

Heres where I am; Installed an SKR Mini E3 V3 jumpered for sensor less homing. I have a BLtouch installed and connected to the board. I Installed a filament sensor above the direct drive.

I have a Pi2 v2.1 attached to the back of a TFT 70 V2.1.

I connected the Pi2 to my wifi a few times before it decided to stop. I thought I did something to the board so I bought another one. No connection. I am 80 years old and sometimes forget things so I could have forgotten the ip address. Could never find the actual one since my desktop does not see the Pi2.

After research I found that I can Klipper print utilizing an SD card and forget the wifi connection. If I can get it connected that would be great, but not necessary if I’m right in thinking I can print from the sd card.

I finally got the TFT70 to show a flash when I powered up the Pi2 but after the Pi2 loads the screen doesn’t show anything. Probably because I can’t find the code or where to load it to make the display work.

I burnt both sd cards for the SKR and Pi2 and flashed the boards.

I think what I need next is to get the display working. Then I should be able to control the printer from that. Then I need the code and where to put them for the filament sensor, and BLtouch. Then load Klipper and figure out how to use it.

Please help.

Phil

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Hi!
Lots to unpack here. I’m going to tackle the RPi bit first (esp. since I don’t know the first thing about your printer of choice)

I was toying with taking me CR-10 Smart Pro over to Klipper, but the 2 RPi’s I have are in use, one for OctoPrint, and the other for PiHole, and that one struggled to run larger prints when it was my OctoPrint server (that’s on my RP5 now). I know when I looked at it, the Pi2b was just barely able to handle Klipper - and the recommendations are to run it headless, so your TFT70 would possibly be a bit of a hinderance.

From the Klipper FAQ:

Klipper will run on a Raspberry Pi 1, 2 and on the Raspberry Pi Zero1, but these boards don’t have enough processing power to run Klipper well. It is common for print stalls to occur on these slower machines when printing (The printer may move faster than Klipper can send movement commands.) It is not reccomended to run Klipper on these older machines.

I also costed out what it would be to move over to clipper, and decided the cost to benefit on this now 5 or 6 yr. old printer wasn’t worth it, and I am going to sink that into it, I’m going for a fully enclosed model that has some sort of AMS (probably not Bambu tho) And probably not Creality again (parts are a pain).

So, not saying don’t do it, but be prepared for … quirkiness.

The new RPi imager tool should let you load RPi OS lite, and let you set the IP address to whatever you want it to be. (I used my ptouch to put my unit’s IP address on the case because I knew I’d forget at some point to move my host table from one machine to another… (and I did, and that past me was grateful to even earlier past me).

In fact that’s how I access that unit today - via ssh or web interface for Pihole. I did set it up originally connected to an HDMI capable monitor and wireless keyboard that had a dongle that worked under linux, but now, the new RPi imager lets me set it up at the time of imaging so yay.

Once you have that, and you’re able to cleanly ssh in (putty’s great for that if you’re not familiar - and I don’t want to make assumptions) you can consider adding the packages for the TFT display.

As for getting Klipper installed, the AI search suggests using KIAUH, but when I try going to the .org page for that, my AV software has a conniption, so I suggest looking for that on GitHub.

The Klipper folks might have something else in their docs starting at Overview - Klipper documentation

I dug around and this link I have gui-v2 working decently well on a raspberry pi 4. Here's how - #13 by BVG - Modifications - Victron Community has some possibly useful info for the screen setup - esp. see the comment by **Jeroen (**Victron Staff) on Feb. 14 (2025 if I’m reading the notes right).

I’m getting out of my depth wrt. the TFT screen, but if you can locate the manufacturer, and any other info about the screen, it may be possible to hunt down how to get it working with the more recent Rpi releass. If that’s a Big Tree Tech screen, then it’s DSI, and that seems to need adjustments to be made to tell the system to use it. (Google’s AI will give you answers, but I don’t know if they are accurate.)

Hope that helps kick start things for you!