That I’m thinking about buying direct drive
What do you want to print that may meed a direct drive?
Flexible filament because I’m into radio control trucks cars boats
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I print flexables on my bowden printers. Though at 82a. Do you think your going to be printing softer stuff?
I print TPU with a bowden, 30mm/s seems to work well
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If you go the direct drive route you might want to install a dual Z axis kit first. The extra weight at the far side of the gantry can cause it to droop and throw your level off. If you watch some of the YouTube 3D printer experts they show how to change the 3 V2 bowden tube at the extruder so it is less likely for the TPU to jam. Simple trick.
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It’s hard to go wrong with installing a direct drive system. I did so with my Ender 3 Pro, using a BondTech clone. The principal reason for doing so is for flex materials and the very low retraction needed for other filaments. I normally print with PETG, TPU or TPE and nylon. The results are very, very good after re-calibrating for the new feed system. The added plus is that I now mount the filament on the top centre of the frame as opposed to side. This makes a better, straighter feed path and free’s up space around the machine.
While i have printed flex without the direct drive, it is only intermittently reliable. Direct drive provides much better feed tensioning for a wide variety of flex materials.
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Don’t you have to print at a slower speed with direct drive extruder?
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@Loosenut - The problem with print speed on a direct drive extruder is that you have a bunch of extra weight moving back and forth that can cause artefacts due to the extra inertia of the print head when it is doing direction changes.
On a printer with a bed slinger design (ender 3) you have two chunks of metal and possibly a slab of glass plus the weight of whatever you’re printing that is also moving back and forth.
It can be argued that the weight of the bed is the thing that is dictating the fastest speed you can print so the direct drive extruder isn’t really handicapping you that much. You can reduce the weight of the direct drive by using a compact stepper motor as long as it still provides enough torque.
Most of the high speed printers will often use a bowden setup to keep the weight down but they also use something like a core XY motion design so the bed isn’t moving back and forth.
Direct drive can save print time in the retracts since they are quite a bit shorter distance. It might allow faster speeds with flexibles since you aren’t pushing a 30cm long wet noodle and are instead only pushing it a few cm so there is less distance for it to compress.
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hi there, I have a ender 3 with direct drive and some other upgrades. I recommend a direct drive kit as mine works great and I can print GoPro mounts and fpv quad parts with it.
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I’m with Blair here. I’d add that it will show a not so rigid frame. I am 50/50 on direct drives. 2/4 of my printers have it. One is absolutely rigid and has little ringing the other I needed to strengthen the frame and reduce print speed to get ringing under control. The Bowdens never suffered this issue. Weight at the extruder needs to be balanced with rigid frames. I don’t know how solid an ender is but the frame of most crealities seem to be an issue. I would consider adding supports and frame braces.
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Good point @kitedemon
Just a general thought, not directed at anybody:
My printers are certainly not perfect and as you get deeper into the rabbit hole of trying to achieve better results you end up getting very diminishing returns for the effort you have output. It’s pretty easy to start chasing your tail and you need to be able to step back and decide if where your results are at is good enough for your application.
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Doesn’t how well the material prints also affect print speed IE: print to fast and layer adhesion drops. Don’t filaments have a “maximum” speed that they can be printed at without causing troubles irregardless of how fast the printer will lay down filament.
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That I’m not too sure about. I’m not sure if its so much the speed of the movements as it is that the hot end can’t melt and push out enough material. Might be a bit of both? 
I don’t really push the speed of my prints so this isn’t an area I have done a lot of looking into
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Your right about it being a “melt and push” limit. Any filament has a temp limit, PLA is usually around 220 I think and if you force it to a higher temp it has adverse effects on it. That limits the amount of filament that can be pushed through the nozzle at any given time. So if you can only extrude a given amount of filament and you bump the speed up it doesn’t print properly like poor layer adhesion as an example. This would be OK if you could increase the nozzle temp. but that goes back to max. filament temperature problems. A vicious circle. This is why I don’t understand how some printers are suppose to be able to print at very fast speeds, like Vorons printing at 500 to 1000mm/sec. You can and I believe they do use something like a Volcano hot end but there is still the filament temp limit. My Ender3v2 will normally print at about 50mm/sec for PLA but it will print at 150mm/sec you just won’t like how the print comes out.
That is the world as I know it, if I have this all wrong then let me know.
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@Loosenut that is not my experience. When I was running a 0.8 I needed to up the temps quite a lot PLA at around 275. Not that the filament ever reached that due to the flow being so high. There is always a limit it is only from trial and error can the limit be found each formulation is likely to be have differently so at some point testing is necessary. Speed has a lot to do with how rigid the printer is, although flow rates also effect it.
I can run my Artillery to 45mm/s before the print quality is really bad. My Prusa with a far more rigid frame will handle 65mm/s. A core xy with a frame that is very rigid and a bed not being tossed around will be able to easily exceed these as long as the extruder can match the flow. Higher temps and delivery through the hot end can greatly increase the flow rates.
I have a volcano on the X1 sadly the frame cannot support the flow rate. Until I changed the nozzle diameter. I didn’t like the 0.8 much so I am using a 0.6 now. It can almost (not quite) print the same speed of the Prusa.
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I was thinking about factors and flow with a .4 nozzle.
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The faster you print the higher the flow and as you start to max the flow rate of the extruder if you raise the temp you can increase the flow rate. The same is true at any nozzle size you just hit the limit of flow faster.
Additionally the hotter you print PLA the harder it becomes. to some extent you can increase the hardness of PLA with temp. This is also seen in annealing the prints after printing. Same thing in many ways.
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Nope, I can operate it faster. A major contributor to speed is shortening retractions. Retraction as you know should be (~ 5 to 6.5mm) for a bowden tube feed system. With direct drive I’m running (~1 to 1.5mm). Each mm of retraction takes time. Lessening retraction reduces time.
My normal printing speed (depending on material and model) is (50 to 60mm/s) with first layer at 15 mm/s.
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I bought direct drive but the printer I put it on I’m still Is trouble shooting other issues and I don’t know if my heated bed failed and what because my power supply works and my motherboard works but if everything plugs in it won’t power up