More and Faster (3D printing)

[Strider_Matic (Tim O.)]

I’ve been working on making my printers print faster and have tried a few things. First, I had a bunch of low torque(39oz/in), motors so I tried with 2 motors per axis on a Piper1 V2.

More Motors?

So i’m sitting here in my lair wondering how I can squeeze any more anything out of my printers and I had a thought…Would there be any realistic gains by adding a second stepper to the X and Y axes of the printers? I have an MP3DP and a Piper1. I asked in another thread about beefier (wow, that work looks weird) steppers to swing the weight of that MK8 extruder and my heavy 1/2"x200mmx200mm plus heater and glass bed. But then I’m looking at it and wondered if I print the X and Y motor mounts mir…

That turned out to work pretty well. Then I bought higher torque motors (84oz/in) on my MP3DP, that works very well also. I consistently get accurate prints at 80mm/sec.

Stepper motor torque question

So I sourced a batch of stepper motors that ended up having 39oz/in of holding torque. The listing didn’t have the specs but I ended up finding out on the interwebs. I currently have them powering my MP3DP and a Piper printer. My question is, if I get higher torque motors, say like the 84oz/in jobs I have on my MPCNC, can I run the printer faster with less chance of skipping steps? The current ones occasionally skip, I think, but then they don’t have a flat spot on the shaft so it could bee the …

Still not fast enough. So here’s my latest (printer) project.

It’s pretty ugly right now since it’s already gone through a few revisions, upgrades, etc. It’s all 2020 T-slot, 310x310 heated bed, SKR 1.4 turbo with 2209s for the axes, and 8825s for the 2 extruders. The printer is based on the following design Cartesian_330X330 bed - v slots and mgn12 rail by mshonak - Thingiverse since it was the only one I could find that just used 2020 rail. I made some changes to the Y axis, again, to only use 2020 extrusion. I’m currently designing my own parts from scratch in FreeCAD to get away from anyone else’s design, plus I had to design a NEMA23 Y bracket anyway, but it will be loosely based on this one.

The big upgrades are the NEMA23 motors being used for the X and Y axes. These run exceptionally well off the 2209s that were already in place. I did have to increase the current near the max of the drivers, but they stay cool with a fan and I don’t miss any steps. I sourced these from a certain auction site for pretty cheap. $14 for 4, plus $12 shipping. So I of course had to buy 8. They have 1.26Nm(178oz/in) of holding torque and work great for what I am trying to accomplish.

So far I’ve tuned the linear advance to .25. junction deviation is at .08. 2000mm/sec2 acceleration for all moves, 200mm/sec for non-print and infill moves. 15% for 1st layer and 80% for outside walls and top layer. Now, I really can’t tell if it’s reaching these speeds because I had originally had my junction deviation set to .01 and it seemed fast, until I changed it to .08, and it’s way faster. Simplify3D says build time is 28mins, but it took 50. Here are some video links printing a 40mm XYZ cube at .15mm layer height and 25% infill. I tried originally with .3mm layers, but the extruder kept skipping steps.

https://drive.google.com/file/d/1z5ZIFgCy2eHhB6GJ7Ur_x2ZjcAm2MolE/view?usp=sharing

20210119_235128.mp4

https://drive.google.com/file/d/1z9R9MqYKvafuvuiOW-FJ4LgARP7jlwRQ/view?usp=sharing

The videos don’t seem to do it justice. It seems a lot faster in person.

Here’s pics and dims of the finished cube.

Extruder still couldn’t keep up with the solid layers. I do have 8mm bore extruder gears on the way though

So that’s where I’m at. Just thought I’d share.

[turbomacncheese (Tony)]

It sure is slinging that bed around! That’s pretty neat!

I’m curious though. If you’re after speed, why not build something with a stationary bed, or a bed that travels on the z instead of the y? Lots less mass…

[Strider_Matic (Tim O.)]

I figure this is just simpler. That would require more (quantity and specialty) parts. I’ve seen some nice CoreXY printers, but I don’t think I’m ready to get into that intricate of a design yet. Kinda like old muscle cars, wanna go faster, just shoehorn a bigger motor under the hood!

[turbomacncheese (Tony)]

I totally get that AND appreciate it! I got a part time job at a machine shop around the time I started my first engine build, a little dodge 8 valve 2.5 turbo for my 86 Shelby charger (the 2door hatchback). Ended up toasting the bearings after 500 miles because I didn’t know what I was doing. Anyway, I learned a lot from those guys, and they were OLD school. The guy that built all the engines…we messed with him one day and didn’t keep anything organized like usual. He walked in to the engine room and everything that wasn’t new or machined was just sitting there in a pile, and he still had it built about an hour before quitting and told us we weren’t leaving until it was in the car and running or he was gonna tell the owner all about it, lol.
Anyway, he always gave me crap “one day well get you to just put a small block in the, junior”
Finally hit the second motor together and took him for a ride. Asked me if we could put on in his Caravelle, lol. We could, but he never got around to anything with that car and ended up scrapping it. He just liked the big motors better, and I came around to understand why.
Anyway, thought you’d like that story, given your choice of example.

[Strider_Matic (Tim O.)]

Now that reminds me about a '80s Chevette my sister had in the late '90s. The engine went on it and I had grand plans to replace it with a Buick 3.8L turbo. I know it’s contrary to my current thinking on this project because there were folks putting small blocks into those too!

[turbomacncheese (Tony)]

Yeah, those 3.8 turbos were little whipping boys, then they updated to the 3800 and slapped a supercharger on em…not bad at all by then.

[Strider_Matic (Tim O.)]

If anyone wants 'em here’s the link to the Nema23 motor parts and associated trimmings.

Nema23 motor mounts and XZ axes for 2020 extrusion 3D printer by torenich

Currently working on a dual extruder carriage that will have the necessary mounts for part fans for the higher speed prints.

Was able to push more plastic through the hot-end with the bigger motors, but I don’t think it can heat fast enough to keep up to ludicrous speed. The extruder gear keeps scraping the filament since it can’t melt fast enough. I think I need to crank the hot end to 11 but I’m going to need to cool the extrusion a lot faster then. So much to do…

[tfaigle (Tom)]

@turbomacncheese yea those were nasty. I was in college when the Grand Nationals then GNXs were the hottest thing on the street. OMG I wanted one but needed a truck with 4WD so wound up keeping my Camaro and getting a truck.

And when they finally post off Chevy and the Corvetter crowd and killed the GN/GNX the Cyclone and Typhoon were the hot ticket. Loved them but they were just not practical for a guy working two jobs to get through college!

[turbomacncheese (Tony)]

A friend of mine traded an 11 second dodge shadow turbo (csx) for a grand national that a kid took apart and couldn’t put back together, lol. He got it running, then traded it to his brother for an old charger (I think it was) that his brother had just painted and replaced the interior. My friend had already rebuilt the engine in it because…he’d traded it to his brother for the shadow, lol.