destroyer2012

I basically followed the instructions here

I have discussed this here viewtopic.php?f=6&t=733

Thanks My machine is up on a little cabinet and so if I roll my office chair up to the cabinet then the screen is at eye level. But if I am standing the angle is annoying, you are right. I might change it later. There are two bolts which stick out from the back of the panel which I can easily attach some kind of angled stand to, and I might just have enough cable slack to do it . Several of the parts I didn't buy specifically for this project but I just had laying around, for example the perf boards, wires, screws, and SD card port. As I said below the images in my original post, I think the total price would be something like $35 at most. I really wish it had more buttons though, navigating menus to move the other axes, or to turn down the flow rate during printing is annoying. Also, I think the finger wheel design works better with a rotary encoder that doesn't need to be pressed. So, I might move that to another button or even better, add three or four more buttons to the panel, for X, Y, Z, E for example.

I decided that Daid was right and I did need a full ultipanel for my ultimaker ! However I did not want to spend >$100 on a legit ultipanel, so what I did was I basically modified the panelmax to fit my ultimaker. I made a custom enclosure for the 20x4 LCD and click encoder and for the SD card reader I used the same board as for my previous SD card reader (viewtopic.php?f=6&t=688) except instead of a soldered in SD card I soldered in an SD card port salvaged from an SD reader dongle. I used this screen ( http://www.ebay.com/itm/190344295723?ss ... 1952.l2649 ) and this encoder (

Just as an update, I installed a PTFE bowden tube in my ultimaker like a month ago and have been printing ever since. No issues with stretching, popping, etc. In fact I just switched out the silver PLA for blue and all I needed to change was the filament diameter in KISSlicer. Everything else just worked, and I feel like part of that is due to how much slipperier the tube is. EDIT: I did have to replace my bowden clamps with these http://www.thingiverse.com/thing:11864 http://www.thingiverse.com/thing:17027 EDIT2: Well maybe I didn't have to... but I did.

I recommend doing this hot, while extruding the filament. Just to make sure you are measuring the right thing

Sorry I haven't tried printing it, only extruded it into the air for a little bit to plug up gaps in my nozzle. Wait what do you mean it's backing up in the bowden tube, is it doing that during a print as a result of retraction? Does it work without retraction? Does it extrude fine into free air? Can you extrude it by hand? What layer height are you trying for? I heard ABS doesn't like to be stretched thin as much as PLA. Are you using a fan? Try without cooling, maybe that will make the ABS a bit more liquidy. I have heard that other people print ABS without cooling. I have never experienced my "filament backing up into the bowden tube" so I have no idea what that looks like or why it might be caused. Maybe you could take some pictures?

Doesn't work. That's what I had before I switched to the other fan.

is your ABS filament appropriately sized? Maybe it's too big so it gets stuck in the bowden tube? Is it forming a plug? Unlikely since your PLA didn't but it's possible. At 260 you might be BURNING your ABS. Try 230? That worked for me.

There are many slicers out there just as easy to use as netfabb but free. For example, Cura, slic3r, KISSlicer. There are only a few things that you need to do to get any of these three to work well: 1) Measure your filament with calipers to get a diameter to three decimal places. EG, 2.705 mm. 2) Measure your extruder steps/mm with calipers. I do it by drawing a line on the filament a known below the extruder, then extruding, then measuring the distance to the line again. Do this a few times to get an average steps/mm. 3) Level your print bed. I do this with a 1 inch travel indicator. Before I got the indicator I did it by lowering the nozzle down to zero and screwing the bed up until the reflection of the nozzle meets with the real thing. That worked OK but the indicator works much better. 3) Come up with a good start.gcode/stop.gcode. This means working out your the z height of your nozzle exactly when its at the home position. Cura and KISSlicer already have pretty good start/end.gcodes, just edit them to your liking. This is all assuming your extruder doesn't slip or jam. And in my opinion it covers the issue of "quality". If the problem is jamming, what we are talking about is assembly issues or design problems. However, if it does jam, there are several things you can do: 1) Adjust the tension knob to press the filament into the hobbed bolt harder. But not too hard! 2) Increase the temperature of extrusion. If you have the plug problem, then more drastic steps may need to be taken, such as re-engineering the bowden clamp as discussed in many threads on these forums. But in my opinion the plug forming is just a symptom of the bowden tube developing grooves from the compression fitting, which is normal. After the plug forms just take the hot end apart, remove the plug, then tighten the aluminum plate up higher without taking the bowden tube out of the fitting. This is made easier by deviating from the assembly instructions a bit and making the bowden tube stick out a centimeter longer than they instruct, so there is a gap between the aluminum plate and the wooden head. Thus, when it does slip the first time you have space to adjust it up. It shouldn't slip again after the grooves are created. Thus, I think it's not hard for general users to achieve high quality assuming they don't run into the plug problem, which has been a buzz killer for many people. However, if you do run into that problem, there is help, and it has definitely been resolved. One must keep in mind that $2000 is actually a very small amount to pay for the type of quality people typically expect from 3d printers. Not to mention, UM is a kit, so if you don't expect to be mucking about and re-engineering stuff or figuring stuff out yourself, stay away.

The rod is definitely bent. Whether I bent it or it was bent to begin with I don't know but it seems to be bowed out in the middle by about 0.2 mm. That means the axis block goes up and down by 0.4 mm as the head travels to the +X. The head probably moves up and down a lot less by lever action, but potentially a non-negligible amount when doing really thin layers. I'm probably just going to disregard it for now because printing at 0.2mm works with no problem. But just a heads up guys: Check if your rods are bent. It could be responsible for why your axes are so hard to move. I loosened the belts just a bit and applied some foosball table lubricant to allow my axes to move better. Also re-squared everything again. The wobble is still there but I think it is affecting my travel speed much less now.

If you use KISSlicer you can get better looking top surfaces because KISSlicer increases the sparse infill density as the printer approaches the top surface. So if you start out with like 20% infill the three layers right before the top surface will be printed in a 50% infill crosshatch so the top layer has something mostly solid to sit on. Printing more than one top layer is preferable; three has worked well for me (with 0.2 mm layer height)

It is possible it was bent to begin with, however, I do not remember what it was like to begin with so I am left with potentially bent rods NOW. I really hope I didn't bend the rods.. I am struggling to see why else that axis block would move like that though. Perhaps my bearings are asymmetric somehow, or the belt pulleys are torquing the rod? I tried loosening all four of the belt pulleys for the y axis and the up and down motion was still there. The rods were still turning with pulleys loosened though, so it is still consistant with bent rods. When I get home I'll take it apart and see. Maybe it doesn't matter but I can only see this problem getting worse over time. Not to mention this might be the reason why my axes don't move as smoothly as they should.

So I've had my UM for about a month now and I've been printing stuff for about 2 hr almost every day, but recently I've noticed a ticking sound while the UM is working, almost like a wood settling noise. I thought nothing of it, oiled my rods etc, but now I noticed that the left Y axis block (the moving block attached to belts which holds the cross bar that the head is mounted to, on the left side) is actually moving up and down as i move the head back and forth along the y axis by hand. SO just to clarify what I'm doing, I am moving the head parallel to the cross bar that I'm accusing of moving up and down. As I move the head by hand I can see the axis block which is not moving sideways (stationary axis) move up and down as if the rod it's on is wobbling up and down, about half a millimeter total travel. This corresponds with the ticking noises I mentioned; must be some wooden part is shifting as the cross bar is being bent out of shape by the wobbling rod. As far as I can tell it's because my rod is slightly bowed. I haven't taken my UM apart yet to ascertain if that is the case for sure but it's the only explanation that makes sense. The question I want to ask is, has anyone else experienced this? What could cause those rods to become bent? I didn't realize I could pull the belts tight enough to bend the rods, maybe that happened? If that is the case, UM you guys better get on this belt tensioning thing! It sucks, and could cause severe damage to the printer if done wrong!

I've had this issue. It's because the captive nut is too far forward. Try pushing it back/ turning it so the flats on the nut are parallel with the left-right axis. That whole nut trap thing is in severe need of some bolts or something... because it's super flimsy. Might want to take out the nut trap and sand it a bit to make the square holes a bit wider. The nut should slide side to side but NOT up and down and it should NOT turn. Good luck!

In my opinion the only reason you would ever need to retract one extruder while pushing on another is to make tool changes. Thus, it could be a pre-programmed tool change sequence triggered only by T0 T1, etc. Although if we did that then we'd have to finally change the E command to be volume instead of distance. Which is really the way it should have been. Printing multiple objects at the same time might be useful for some things but no commercial machine does this, and I don't see why we should build our whole firmware-software architecture around something so specialized. Besides you could just put in a command to select all tools and still print multiple objects with only one E command per line (volume).

I feel like firmware side support is the way to go... just like how acceleration used to be software-side but then switched to firmware-side because it was faster. Firmware-side multi-strusion would give us more flexablity in terms of being able to specify idle modes, extruder specs, etc. After all, you are more often going to change your software than change the number of extruders you have. In my opinion.

well, we already have the two parameters E_steps_per_mm and filament diameter. Those two together give you a volume extruded, and are both fairly easy to measure. They work fairly well too, as you can see people on this forum have been able to print at very tiny layer heights indeed (0.05 mm?). At that height, any error in volume extruded becomes disasterous, and the fact that they are able to do it means measuring those two parameters works fairly well. I don't see how you could use weight to measure the volume of filament going in. You could measure the amount of filament coming out but then you can't do that during printing. One thing we could do with those sensors, however, is measure the amount of pressure applied to the filament by putting that sensor on the bowden tube. Bowden tube stretch is likely proportional to the force pushing the filament, which is in turn proportional to the rate that extrudate is coming out. Since we also know how fast the filament is being pushed in (extruder stepper) we could set up a control system to make the pressure on the filament stay constant, or make retraction much more effective by retracting only enough to bring filament pressure to zero. If we could regulate filament pressure, I think we could do a lot to eliminate strings, blobs, and filament slip, and the machine could be much more failsafe. The question is whether putting a sensor on the outside of the bowden tube would even work; whether its sensitive enough, and whether there is a better way to solve those problems besides adding more complexity. I wonder how much those sensors cost...

I disagree. Both slic3r and cura try to simplify the process of turning stls into gcodes, so they are comparable from a user standpoint. You may have lofty ideals as a developer but I don't care when I'm just trying to slice an stl, slic3r and cura seem the same in my eyes. well that's funny because I've had the opposite experience a lot of the time. That's why we are having this discussion. You say slic3r lacks features, well I think cura lacks a lot of features too in terms of parameters we aren't given access to.

is your fan on all the time? You'll want it on for overhangs. Try going a bit slower.

Multi-input nozzles have been tried. The results suggest that good mixing is ESSENTIAL, and this is complicated by the fact that plastic is very viscous and doesn't mix well at the temperatures we extrude at. A tip that mixes the plastic automatically (like those epoxy nozzles) would be nice but that would be a fairly large volume of plastic you would be throwing away with each color, as you'd have to flush out what's in the mixer tip to make the next color. You could try to predict the upcoming colors and push in the appropriate filaments, but I just don't see that giving you enough of a solid color, more of like a shade of the previous color that was in the mixer. But that doesn't mean you shouldn't try it!

I am curious if anyone has had good success with retraction. I have tried (at Daid's suggestion in some thread) retracting 2 mm at 50 mm/s and priming 2mm after but it seemed I was net losing plastic and oozing was not really going away. I noticed that he had done that at 200C whereas I am printing at 230C, which is considerably higher and my PLA is considerably more like goo. We've all seen the crazy stringy prints people have been getting. Does anyone mind posting pictures of how retraction improves print quality? Anyone got any good examples of prints without strings as a result of proper retraction settings?

check to see if your axes move smoothly (ish... mine still require some force to get the head moving, but I would say like a moderate amount). Make sure they are aligned and the belts are tight. Loose belts cause the axes to skew during fast moves and that may make them bind. Those belts are such a nuisance!! How fast are you trying to go? To get rid of this problem I had to realign my axes (using a pair of calipers!) and grease my rods (I used silicone grease like for foosball tables). I also slowed my printer down a bit (200 mm/s travel instead of 250). Some people have had success with taking the brass bushings out and sanding the insides of them to widen them a tiny bit. I was too lazy to take my printer apart to do that, but you might have to.

just an update: I recently installed the printed bowden clamps and i must say it is much better than the stock compression fittings. What I did was: -insert the bowden tube through the printhead-side of clamp ( http://www.thingiverse.com/thing:11864 ) and extend it down too far. -Then put the PEEK part on the end of the tube and thread the aluminum plate onto the ends of the head screws as it's holding the PEEK/nozzle assembly (don't tighten anything yet). -Now, tighten the knurled part on top a bit so the bowden tube doesnt move freely, and then tighten the four screws holding the aluminum plate all the way. -The bowden tube should remain firmly pressed into the top of the PEEK part as you are tightening. After tightening the aluminum plate then tighten the knurled part on top all the way. I used the "extra grip" insert to hold the bowden tube. I left the white part of the circlip on just to guide the bowden tube down the middle of the wood hole, but you shouldn't have to. Or you could replace it with a circular printed part as it's just a guide and doesn't have to grip. This setup is now working wonders on my printer. Granted, I don't have two print heads, but it should be possible to do it with two. You just have to modify the printed bowden clamp stl to have two threaded segments.

What i've observed with the circlip is that after an initial "digging in" state where the tube appears to slip, the clip makes indentations and gets a good grip on the bowden tube, which prevents further slipping. SO what I've done is just run the printer, let it slip, then cleaned out the plug and tightened the hot end back up to the new higher height. Works well. I know that won't help you because you are trying very hard to get the heads exactly level, but perhaps what you could do is something like that to allow the clips to dig in, then take apart both heads and cut both tubes down to exactly the same length. An alternative might be using the printable bowden clamp? That thing grips REALLY good and has a wide grip footprint so it doesn't need to "dig in". I am not currently using that method myself but it seems like it would make more sense than the circlip. good luck! And could we see some multi-color prints that you have made with the setup?