The tramming/leveling routine can be run as a stand-alone X3G that we just put on my SD card, but in my production environment I prefer to have it as part of the start.gcode for every print. The printer comes to operating temperature (so there isn't any hard ABS on the nozzle tip(s).. and so that the unit has thermally stabilized), performs the tram, and then immediately starts printing. It adds ~10 seconds to every print.
As a caveat and reminder, this system will not compensate for warped or otherwise deformed build surfaces. It will take three points on the build surface, call that a plane, and set that plane parallel to the XY motion plane. If there are mountains and valleys in-between those three points the system has no way of knowing.
As I mentioned at the beginning of this diatribe, I have two machines with this system currently installed, and there will hopefully be a third in the next week or so. To-date the results have been quite, quite promising... and the first layer repeatability has been as good if not better than what I can achieve with a methodical traditional manual approach.
The really great thing about this design is that it physically moves the bed to a trammed position using the Z motor and nozzles. That eliminates a lot of the issues with repeatability that height-sensing switches have. (Switches don't always switch at the same distance/travel.) The only position-sensing switch here is the Z axis limit switch, and tram gap positioning is relative off of that... So there's no error introduced from switch travel variation.
As long as your nozzles are even and build plate is flat, this is pretty bullet-proof.
You totally missed the operation.
Replacing the three leveling jack-screws are three "gimbaling pins", and there are three corresponding pin clamps built into the span/spreader plate. These pin clamps can lock the gimbal pins at an infinitely variable Z elevation.
That really is a beautiful, elegant solution. Well done. I hope you release the designs at some point, I would love to add one of these to my machine.
The gear-cam is simpler than one might think... but it's also a bit of a bear to print. You only need to release one clamp at a time to do the tramming, so there is only one "inverse lobe" location... with a lot of dwell.
Once you get your head wrapped around the way it works, you'll probably just say "duh".
I'm almost afraid to ask, but... Do you intend to patent this mechanism? And if you do decide to patent it (and the patent is granted), would you consider giving a license to people who build their own for personal use to do so royalty free?I know that if I built one and it worked well I would happily "buy you a beer" and then some (It's a great design!). I'd be quite disappointed if I wasn't allowed to build one of these marvelous devices myself one day.Again, this is a great idea, and thanks for sharing how it works with everyone!
Fri,I'm not trying to be a jerk here (I don't have to try, it comes naturally)... but I don't consider my implementation to be ready for public consumption yet. I'm just a bump beyond Alpha testing and am just moving into Beta.There are hardware refinements that I am currently working on, and the software side is being pondered and refined as well.I'll discuss the implementation all day, but I don't want to release any source yet. I prefer to slow-roll this a bit.