Originally shared by Jeremie Francois Part two, and the actual design and motives:

(Jeremie Francois) #1

Originally shared by Jeremie Francois

Part two, and the actual design and motives: I hacked my Ultimaker so it now boasts a fully automated bed leveling and tool height adjustment. No more hacking with the Z-screw, Z height adjuster, nor Z underside thumbwheels. I hope I’ll forget everything about Z-wth.

(René Jurack) #2

There is a german http://reprap.org user, that has done nearly the same thing, just with ordinary RAMPS or RADDS with extension for 3 Z-Steppers. (link: http://forums.reprap.org/read.php?336,565658 ) He uses an ordinary (micro-)Arduino for computing and it’s done IN the firmware itself. Still, pretty amazing job! Keep up the good work!

(Jeremie Francois) #3

I love it when google tries to translate German (that I barely can read natively), such as: “Is there Empfindlichkeitseinstellbarkeit already?” :smiley:
It’s a bit hard for me to get it all though… especially as it is a 14-page long discussion. Not sure I will have the patience and make the effort to read it all thus, but it is a pity as I am sure there are interesting pieces of information to share. Looks like there is some info that gets lost because of language :frowning:

(René Jurack) #4

You are surely welcome to this thread. Sharing knowledge is always wanted there! The users there (including me) are surely willing to explain things…

(René Jurack) #5

“Is there Empfindlichkeitseinstellbarkeit already?” - This means “is there a way to adjust the level of sensivity, yet?”

(Jeremie Francois) #6

I could not help but dig in the thread (thanks for the help anyway – would love to spend more time in forums also). I saw they also had to avoid the FSR saturation, and did some nice boards.

(James Rivera) #7

@Jeremie_Francois I finally got around to reading the whole post. GREAT work! You are really showing your technical ability by skipping the Arduino code on the slave and making use of interrupts for better control. Kudos! Also, nice work on the improvements–you saved me some typing. :wink:
For now, I’m still using an induction sensor and software compensation on my Printrbot LC+ v2, which works well enough, but I’ve really been wanting to build a printer that only moves the bed in the Z-axis. I know the UM1 uses laser cut panels, but you have me wondering if I should try to make them on my OX CNC. I will probably not do that because I’ve been eyeing an aluminum extrusion version of the Ultimaker (e.g. Eustathios) for quite a while, but still…this just makes me want an Ultimaker even more! Again, great work!

(Jeff DeMaagd) #8

So it actually levels the bed rather than do constant z motion to compensate for bed skew? That sounds like a much better solution if you can stand the extra cost. And I bet that makes the bed more rigid too.

(Jeremie Francois) #9

@James_Rivera thanks for all the kind words :slight_smile: May be… I would gladly trade a bit of my software skills for hardware skill (or at least hardware productivity – I am not lacking ideas but when it comes to realize it always takes more time than expected)…

(Jeremie Francois) #10

@Jeff_DeMaagd yes, constant/common Z is done only when printing. During calibration the 3 Z are independent. Some group the 3 FSR sensors in parallel, but I found it much more reliable to be able to filter them separately (the weight/placement has a lot of impact on the signal, and putting them in the same bag probably makes it way trickier to get a nice on/off state in the end). And yes, making the bed more rigid was one of my first goal. Being able to auto calibrate was a nice and logic second step :slight_smile:
There are some ways to make it cheaper. E.g. instead of 3 NEMA 17 and controller, I think that 3 of those Chinese dirt-cheap $5 stepper motors with their ULN2003 drivers would be possible: 3 of them are driving the bed so we need less torque and speed is not really an issue for Z.

(Jeremie Francois) #11

FYI, I just added a “make it reprap” addendum to the post with different options to get the whole cheaper. / cc @Jeff_DeMaagd