FYI, just ordered some 3mmID PTFE off McMasterCarr to try out with the new direct drive setup:
McMaster-Carr
Could have got it for less from amazon/ebay, but it all ships from china, takes a month, and the shipping cost makes it about a wash.

 

I decided to move the bed arms all the way out and used a mount I modified so I wouldn't have to use any extra extruded aluminum pieces. Seems to be working pretty well for me! as far as extruding petg goes this forum has helped me immensely MakerGear Forum • View topic - Print Settings for PETG: eSUN Solid Black Filament

CoreXYbedmount by Dre363

 

Yeah that PTFE from McMaster is 3mm/5mm and the regular "3mm filament" stuff is 4mm/6mm with 6mm/1/8" fittings so it won't push into the regular 3mm OD fittings.

Here's a quick part for making a 1/8" push fit connector go onto the front crossmember so it can be used for a filament guide.


EDIT: Now looking at the picture I wonder why I didn't make it go into the vertical extrusion slot just to the right of that!

 

I just built that, it seems to be working fine. The problem is there's no option to turn off the cooling to the print. There's a remix that adds a switch to allow this though, but it's clunky.

 

Yeah I had seen that and it certainly looks neat, but I don't want always-on cooling. I only use the fan for cooling layers with short layer times and bridges so it needs to be able to be controlled from G-Code.

 

These combo fan ducts seem like a bad idea, if the fan gets switched off or cycled down at all you could risk damage to the hot end or at least get unwanted melting into the cold end.

 

Yah, I wasn't too sure about the push-fitting, but I really don't care: That's what zip-ties are for

 

The strings r from being too hot - try 195 for other than first layer and 200 for 1st.
Mine r now extremely fine and few. I don't know if I can get them to go away totally.

The fill in looks like under extrusion. It could be from setting the nozzle too close to the bed. This blocks the flow. First layer height is normally 150-200% of layer height. U have 90%, this may be why u r getting the Z setting too low. 0.90 for extrusion multiplier is probably too low also and that would contribute. I would go back to 1 while u r trying other things.

Retraction over 4mm is a jam waiting to happen for PLA. Trust me. U may get away with it if u r printing very fast.

The main cause of prints with blobs in the corners and other places is a low JERK setting. If you increase the JERK setting you will see the blobs go away. If it is set too high you will get ringing on the corners.

I have been thru all this stuff on mine and wouldn't u know somebody else already discovered the answer - surprise. Good thing for me - and u. Let me know what fixes it.

 

Try reducing the jerk first to reduce the ringing.

 

Yes, I think I am @ about $800.00, but I also bought some extra stuff, and modified the platform - but I ended up with some free stuff also (not much). That is for a 12x12.
One of these days I will add it all up.

 

I didn't see anything in the file section that had these files. I downloaded the zip file with the stl, but everything there was dated 10/19.

 

Thanks to you both!

Picked up the extrusion over the weekend along with a bunch of hardware. All that is left are the screws and flex couples.

Cheers!

 

Holy cow, it says 98 more messages unread!!! Pack, move, unpack, rent house with badd juju, buy nice new house, pack, move, unpack divided by toddler equals not enough Kg of melter plastic. Funny, I had a google now card post up about @AK Eric and his switch to direct drive made me get my printer turned back on.

How are things going in the direct drive world? Are you ready to take the big plunge and come to the dark side, start using MBI stlye short thermal barriers? I am really glad to see such great prints across the board.

 

Just got the 'beta v2' Direct Drive setup printed and installed last night. Thoughts on it:

• Based on my Rep1's print of it, the tolerances for the filament hole and lower ptfe hole were spot on: Didn't need t drill them out this time. All the captive nuts snapped into place just like before.
• The new front clamp that holds in the ptfe tube works great: Makes it super easy to get it sized correctly the first time. With a little more work it wouldn't be hard to get cut just right on top to form a nice upsidedown-V that would tuck inbetween the hobbed-gear and the compression bearing, allowing (hopefully) for filament like ninjaflex.
• Still the same width: I was (maybe mistakenly) under the impression it would go back to the original 'single extruder' size. Not a big deal, but would be cool if it could.
• Loading filament is much easier now with the extruder moved a slight bit over. Seems to extrude just fine.
• The holes in the back work great for @trublu832 's fan attachment.
• I don't remember if beta v1 had this issue, but the top left wheel is maybe 1mm away from the stepper. It has clearance, so all good there, but it's darn close.

So I'm totally sold on this new system now. In fact, I love how the stepper is slightly moved away from the hotend, to remove any possible heat-creep type issues that have effected my Rep1's direct drive in the past. Only request would be to see if it could have it's width brought back int to allow for more play on the X-axis (basically saving me from having to redesign my x-endstop ). Thanks again @Carl Feniak !

 

Do you think that having the motor above causes a pendulum effect? I had originally planned on dual extruding, mounting a stepper on the rear, balancing the gantry, but I will need to increase my frame about 60mm in the Y to achieve this. Anyone though about using the pgl35L's?

5PCS Collision Switch Limit Switch Travel Switch for Robot brand new I wasn't the one who found them, sorry I don't remember who had originally linked them first. They are a nice compact switch, 20mm wide ( conveniently ), make a great z switch.

 

Hi guys,

I've been lurking in the shadows, gobbling up all these STLs

I've printed out the direct drive parts, but modified them for using a Hexagon hotend. I am also currently printing out a bracket that attaches to the back of the X plate that is a combo fan mount and endstop switch holder. For my X endstop switch (I home to min), I ended up de-soldering the actual switch from the mini circuit board so I can "remote mount" the switch (different orientation) from the endstop switch board.

If I get it all working, I can post up some pics and STLs if anyone is interested.

-Joe

 

Printed up the parts and starting to assemble now. One thing I noticed with my print, the holes for the nuts are not tight enough to actually capture it. It falls out if I turn the piece over. That's about as far as I have gotten so far. But it is looking real nice.

 

That's what I am doing. Just waiting for it to dry a bit and will test it out. Thanks.

 

@adamcooks : I don't think there is any sort of pendulum effect: I have zero slop in my x-gantry, and I can't imagine what I'd need to put up there to cause the lower bit to move differently than the upper bit. It's pretty rock solid.
@Elmo Clarity : Yah, my nut holes are press fit: If they were any smaller, I wouldn't be able to get the nuts in at all. I currently have to use a pair of pliers to get them in. Which is really weird we'd have such different print results, yet when I do dimensional accuracy tests on my rep1 it seems spot on. I am printing with 5 shells for strength, but I don't think that should have any effect really?
@Carl Feniak : Clearance on that wheel is close, but is ok.
@Joseph Ecker : New designs are always cool. If I can find something to move my endstop to the X-gantry, I'd sure like to look into it

 

What I have seen with dimensional accuracy is if you get the outsides of an object correct, the inside will be off. The outer diameter of a ring will be what you asked for, but the inside might be bigger or smaller depending on how the slicer slices it. The extra shells, I am using 3, could make a difference. I originally printed the parts for the printer with 5 shells and found the holes for the screws to be tight. When I went to 3, they were still tight, but I could push the screw through with a little effort.

 

It never fails. I get all the nuts glued in and when testing out the last one, it strips the hole. Now I get to print the front piece all over again. Maybe wait for V3 to come out.

 

The problem with the striped hole is some glue got into the threads. I thought it had dried enough, but I guess there was still a little that wasn't.

Measuring the hole, I get 6mm flat to flat. That dimension on the nuts I have is 5.4mm.