The build platform needs to be parallel to the plane that the nozzle is moving on, but that also means it needs to be perpendicular to both the X and Y axes. If your platform is oriented at 90 degrees to both the X and Y axes then it form the expected Z axis of your coordinate system.
@Stephen_Baird Not sure what you mean about the platform being perpendicular to X/Y. It should be parallel to them The X and Y axes are lines, those two lines form a plane (the X/Y plane). Nozzle movement within a layer is parallel to this plane, and the platform (also a plane) is parallel to that one, while the Z axis should be perpendicular to both of those planes.
This is getting a bit out of hand.
We should all be civil and respectful towards each other when having any discussions.
Please and thank you.
If you out a square on the bed and move it around, if it stays square to the verticals then the bed is square to the frame. If you then put the square against the uprights and compare to the xy rails and they’re square you’re done right? Its harder for a delta but the first step is the same and an absolute requirement.
@John_Davis , the term plumb, and the term level, taken by themselves could be misleading.
But, when taken together:
A level X-Y plane, with respect to gravity, and a plumb Z-axis movement, also with respect to gravity, is exactly what is required.
These two terms are easily understood by laypeople, so perhaps they would suffice?
In technical terms what we are after is that the Z-axis movement with respect to the X-Y plane must be a geometric tangent, or a surface normal.
But the “tangent” and the “surface normal” are not concepts readily accessible to a layperson, so when explaining to someone new, I would consider using level and plumb.
@Brad_Hopper Except that you need to check the nozzle’s direction of movement directly against the platform rather than checking both of them against some third thing, like the Z axis or frame components, compounding error in the measurements.
Parallel makes me think of parallel bars at a play ground. Not sure how parallel fits in relation to the height of the nozzle with respect to the bed.
What makes most scenes in my mind is , leveling the bed with respect to the Z but that puts the word leveling back in and that is what people are wanting to get away from also.
Google says one definition of level is “a height or distance from the ground or another stated or understood base.”
Level works fine. Stop being so nerdy.
@Dave_Durant Level does not work fine, and it never will as long as there is a tool with that name that looks like it can be used for the purpose, but will give the wrong results.
@Wayne_Friedt , I would not think of this discussion as necessarily moving away from the word level.
Rather, we should be discussing terminology that brings everyone, or at least most people, the greatest clarity.
Framing this discussion in a positive way: we are all seeking clarity - to use words that are as clear as possible, and perhaps especially to laypeople, in deference to the “Open Source” concept.
Every word we are discussing here has its benefits and drawbacks, so it may be best to get new ideas, evaluate at all the options, and then weigh things up carefully to draw a conclusion.
@Dave_Durant I am proud to call my self a nerd. Better that a lot of other thing i could be labeled. Also i see nothing wrong with discussing a topic that has some issues in a group. Everybody is very civil with no name calling ect. It is for the better of the group to figure out what to do that is an amicable agreement.
@Whosa_whatsis , the word ‘level’ will work fine for a layperson, when combined with the word ‘plumb’.
If I were to tell somebody that I needed to make my machine’s plate level, and that the extruder head must move plumb, then they would understand exactly what I meant.
The only place I can think of where these two gravity-related terms would not apply is on the International Space Station - a very special case!
Tramming is dead wrong IMO, as is parallel. Square makes the most sense as an alternative to level since the bed “should” be 90 degrees to the hotend and therefor “square”.
The word tramming is not common enough and requires explanation. It originates from aligning a wheel (like on a tram) to be perpendicular to a surface. Align is in more common use and means virtually the same thing and could apply to machines that are not orthogonal like deltas.
Orthogonal?
The problem is that if the z axis is tilted, it can be tilted in a multitude of ways where the bed is still on a parallel plane with the x and y axis. It is true that the movement needs to be square (the y axis perpendicular to the x and z axis) so that prints don’t come out oblong, but what is really the issue is that the movement of the x and y axis to be coplaner with the bed. You could call it normalizing, as what you are doing is making the surface normal of the x and y axis equal to the surface normal of the bed. Squaring would be making the axis perpendicular.
@Paul_Gross I hate to disagree, but as a layperson (with respect to most machining or mechanical issues), I find your description more confusing than when I realized that ‘leveling’ my first printer’s bed had nothing to do with being level.
As a long-time programmer, I find this discussion really important. The correct name or term can save loads of documentation and discussion problems. I like parallel better than level, square, or tram. Unfortunately, the fact that several people have highlighted potentially legitimate points for confusion suggests that we have not found the correct term yet.
@Whosa_whatsis Thanks for collecting the thoughts on this topic to one spot. I had not seen any discussion of this and appreciate seeing how people are thinking on the topic.
Hi @G_Wade_Johnson ,
Please don’t worry about disagreeing with me - no harm is done as we are just having a polite discussion.
I am unsure exactly where your confusion arises when aiming for a ‘level and plumb’ machine.
In my mind, if you level your build area (with respect to gravity), and check that you z-axis rise is plumb (again with respect to gravity) then your machine should be correct.
As @Stephanie_A has said above - your Z-axis, when plumbed to a level build area, must then follow the surface normal from the X-Y plane, and your prints will be true to their designs (all other aspects being correctly calibrated).
What have I missed?
Hi all, just to put my two cents worth in, I do not believe one word is adequate to describe “ensuring the build platform is parallel to the relative plane of travel of the hot end” and some terms will be immediately understood by some and equally the same terms will be confusing to others, I think trying to define a single term is only going to upset a lot of people, working on a common description I believe would be more valuable to beginners/laypeople like myself.
When I started learning about printers, I came across, tram (this meant nothing to me, and required a lot of searching and reading to understand), level (this I sort of understood, but I would have reached for a spirit level until I had read further), parallel (the initial question was parallel to what, then why, then oh I see).
If you want a single term to describe this I would suggest using an acronym, of course this could be derived from the agreed upon phrase, when a concensus is reached the main thing will be consistently using it until it becomes the standard term.
Regards.