It’s alive!
Lots of new toys on that build, must be like Christmas finally putting it all to use!
Linear advance seems like a really solid option, never thought about how much it must help a bowden while printing super fast. Perfect pair.
When looking into Linear Advance for the first time, be sure to check the version that’s being described. Newer versions end up with much smaller values (by an order of magnitude) than the original version, and there are a lot of tutorials out there that might have you start with a value way out of the current ball park.
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@ttraband yes, you’re right. I was thinking of my older setups. The current generation of linear advance uses much smaller #s and yields better results.
Yep, and linear advance needs to be tuned. I have to get the bed level working before that will work though, and the bed isn’t in exactly the right place, so it is probing off the edge when I try to level it, because I offset the bed with my goofy mount… So, I have some work to do still.
I will say that the motion system seems to be doing much better. I very carefully adjusted all the nylock nuts on the idler screws. That seemed to help a lot. I also found this:
So I flipped that around… 
I added grease (some thicker stuff) to the leadscrews and some chain oil to the linear rails. That helped a lot too, but I was then getting lots of skipped steps on the Z. I have some 16T pulleys, and I grabbed one and showed it to the motor, but didn’t swap them out. That seemed to scare into working. I also adjusted the leadscrew height to lift it up a tad, which I think reduced the friction against the bottom of the plastic mount.
I flipped and flopped the settings and the wires around until I had the coordinates the way I want them. If you are looking at the logo on the gantry, I wanted X+ to be to the right, and Y+ to be away. Also, because I’m still using sensorless homing, I wanted Y_HOME_DIR to be +1. G28 works reliably for the dozen or so times I’ve tried it.
I am very happy with the printer. The design is simple, and it is very customizable. The motion system works well, AFAICT. It will take a while for me to just get used to how fast it is. My other printers are so tame by comparison.
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Tune it in, we need to see a video at some point! Faster printing could really really really, did I say really, help me out.
I need to get better at video editing first, so I can speed it up, and make it louder. 
In your production, if it was 2.0x faster, but 2.0x more expensive than your MP3DP would that help? I imagine it would help when making a pile of prototype primo parts, but having twice the machines running for twice as long seems like close to a wash.
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Here is a short video I took while it was printing that block. This is the starting position, which is already quite a bit quicker than the wanhao:
FYI, That object is the default object and those are the default slicer settings for gridbot v2 in kiri:moto.
In that scenario no, because any issue means any breakdowns hurts more with the twice as fast printer.
Fast and quiet. I need to see how many of those bearing rails I have on hand. Seeing new cool printers is awesome and makes me want one.
Got a note on OpenBuilds from someone who is in the process of building 10 GridBot V2s. I’ve asked for more details. This intrigues me.
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You need a GridBot v2 bot. Something that can make grid bot printers from scratch .
I am not in a good position (yet) to recommend it. It is just waking up for me. Feel free to point them to this topic to see what I have said about it.
Are you thinking about selling the flat parts and/or printed parts as a set? That might help smooth the initial transition.
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I need to revisit Kiri’s defaults. I haven’t tuned them or even looked at them in a long, long time.
Any cube like object it printed would have made me happy at that point. I am not done messing with the slicer settings, but if you have some settings that work for you on an ideal printer, I would like to check them out.
OHHHHHHH, that is how it all starts. You are about to be a hardware company!!!
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I have three teenage sons home for the summer. My eldest is interesting in making GridBot kits.
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Um, perfect! I am looking at it, and you may want to design an electronics enclosure(s) so the parts fit in a standard flat rate box, but otherwise, it would be a pretty effective fit.
He can even enlist the smaller ones into counting bolts.
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Hey Jeff, is your belt missing a chunk by the hot end?
On the right in that video? That is some adhesive left from the tape that they used to keep it together when shipping it to me. I need to clean it off, although at that spot, on that side, it doesn’t touch anything.
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@stewart, Do you have any tips on bed leveling? I know that is a big question…
I have been using UBL, like your software, and I’ve used Bilinear in the past. I set the number of points to a 5x5 grid, and I’ve done and saved the G29 P1 grid. It looks like then, at the beginning of a print I should do G28, G29 L0, G29 J. Is that right? I’m having some low spots and some high spots which are a bit annoying, so I’m not sure what’s causing that.
The bed is generally pretty consistent. It is 0.3mm at the high spot, and -0.3 at the low. Which is enough difference for me to need to compensate (or buy a flatter bed), but not enough for me to worry about goofy artifacts when printing big pieces. The bulge is bigger with temperature, so I think I need to make sure I always probe it at operating temperatures.
I’m thinking about increasing the number of points on the bed probe to 7,8,9. At least with UBL, I wouldn’t have to probe all 81 points on each print.
Actually, now that I think about it, I wonder if the G29 J is causing me problems, because the probe points from the grid aren’t that close to the edges, and it is probing to tilt the mesh by probing at the very extremes. Maybe I’ll just pull in those 3 probe points to be inline with the probe grid, and that would be more consistent. Thanks! 
I use a 5x5 grid. once I’ve enable UBL, I only do a G28 at the start of the print.
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That makes sense.
I got my pi screen today. I have a lot to learn about this interface, but I will take a close look. It seems to be well suited for this printer. I might edit a few things, just to get familiar with it. I think in gcode too, so I am still working through what the different buttons actually do. The touch screen is so nice to have. Is there a baby stepping menu item? I saw in the config the Z probe offset, but I like to fine tune that value when I’m watching it print the skirt. Maybe that is something I will try to poke at.
I didn’t try the DC/DC converter until today, and the one from the BOM doesn’t seem to want to reduce the output. I turned the trim pot for a while, and it didn’t seem to end up anywhere else beside 23.3V output. I have another one though, and I used that instead (no pi’s were harmed, I was safe for once).
I will say, I am getting pretty tired of removing the back electronics panel. I think it would be great to mount a bracket inside the 2020 frame to the 2020, with those hammer nuts, and then have something to screw into to attach the back panel to. The back panel is just annoying enough trying to get those 5 hammer nuts in place every time I need to get back there. I have been trying to make my trips into that door more efficient by combining updates. Things like that. If the hammer nuts were always keeping the brackets on, and the brackets had captured M5 or M4 nuts, then the back panel would be a lot easier to get on and off.