Printable View
Working on a new CoreXY printer
and was hoping you guys could give me your two cents on the basic idea of how ABL is handled in this gantry design
A Special gantry for openbuilds vslot using Mini V wheels
it also include the ABL (Auto Bed Levelling) Micro switch so when pressure is applied to the nozzle it hinged upward slightly to trigger the microswitch
http://www.thingiverse.com/thing:1737901
Video https://youtu.be/MJS9SiPSY3Y
https://youtu.be/MJS9SiPSY3Y
Do you have one working? Do you get good M48 numbers? Is that spring in the center where you set how much force it takes to lift up gantry?
Haven't had time to test it. But it only needs to lift a tiny amount to trigger the switch. And yes spring is to set tension
Here is it working. https://youtu.be/Iq-L2mW2IyM
Let's see it doing an M48 V4 P10 !!! This is a very elegant design. The only thing that I'm not sure about is whether I can use it. I really need to have my heat bed on springs because any firmware mistake drives the nozzle into the bed and I need a little bit of extra flex so I have time to press the reset button. I guess if my heat bed springs don't deflect as easily as the nozzle deflects, I might still be able to make it work for me.Quote:
Originally Posted by adamfilip
Well my bed is completely solid. and my Gantry cant go down that far. it hits a physical limit.
if it tried to drive down.. the spring would take up the pressure.
I will try the M48 V4 P10 when I get home :)
This seems very similar to the Atom 2.0 Printer:
https://www.youtube.com/watch?v=ygHrhfxhx38
It has its ABL sensor triggering in the same manner.
Yep, that printer inspired me to make this version.
Its a fantastic design and I am excited to hear your experiences. I have never used ABL because I always read about random issues with the servo for the arm,starting G code, etc.Quote:
Originally Posted by adamfilip
So if something like this becomes popular I may try it.
Havent had a chance to really print with it yet. been testing and tweaking so many things related to the printer..
but I will very soon i hope
Here are the results of the M48 V4 P10
READ: Mean: 0.664402
READ: Standard Deviation: 0.002912
so whats considered a good result?
Hi
If you are trying to print a layer height of 0.2 mm, a bed that is good to 0.02 is "ok". Anything at 0.002 on a 0.2 mm layer is well beyond what you can see. As you scale layer height, the limit (obviously) changes. It is not at all unusual to look at a "three sigma" (three times the standard deviation) to estimate how good the result will be most of the time. If you have a very un-level bed, and are taking a lot of points, that figures into the estimation as well. On a dead flat aluminum bed, I may only need three points. On a monster I may take a 5 x 5 array. With three points, the flat plate may well be better overall than the crummy bed, even after 25 point correction.
Bob
Are you referring to the Mean or Standard Deviation?
.003mm of standard deviation is good. Especially if that was accomplished with 10 probes. I've been able to get numbers down at .001mm but I have my probe leg designed to not move at all. Considering you are moving a lot of stuff to get the switch to trigger, .003mm is perfectly respectable.Quote:
Originally Posted by adamfilip
HiQuote:
Originally Posted by adamfilip
The mean is simply whatever the nominal offset to the probe was. The standard deviation is what tells you about the repeatability. Assuming you did a few dozen trials, the SD looks pretty good. If it was over a small number of trials, you need more data.
Bob
Just updated to Marlin UBL v2 redid the probe test
nice results! from M48 V4 P10
READ: Mean: -0.997358
READ: Standard Deviation: 0.000677
:)
Hi
It looks like your data is pretty good.
You might want to see if this can be moved to a more suitable sub-forum. This is the MakerFarm section and they don't have any CoreXY stuff.
Bob
sure, but this isnt corexy related really.. I am planning on making a version of this hinged gantry for my Makerfarm i3v 12