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I'm getting really frustrated with my RMax... I'm about to just sell it off and buy an Ultimaker clone or something. I've spent all my time on it trying to get it to do what I want, I haven't been able to actually USE it to make anything that isn't for the printer itself.

After tweaking and tweaking and tweaking, this is the result of my test print of the Maker Faire robot (http://www.thingiverse.com/thing:40212). Tested 0.1mm and 0.2mm layer height, with various speeds and temperatures. Bed's calibrated, adhesion is good, temps are stable, vibrations are minimal. This is with a single E3D hotend.

[img]http://i.imgur.com/je07d9o.jpg[/img]

The pic isn't even showing the worst of it. I look at the other "makes," and they look really decent.

$20

You're probably not far off.

layers look pretty good, it looks like the dingleberrys are leftover plastic that was stock on the nozzle and comes off at random times. What exactly are the issues you want to correct?

What slicer are you using?

No, I was watching the whole print, no dingleberries at all. It's hard to see in that pic, but it's actually much worse. Those are how the layers printed... mushy. I tried setting a lower temp, thinking it was just too hot, but that wasn't the case. It can't print overhangs worth a damn, and I think that's the problem. It should have no problem with those overhangs, supports shouldn't be needed, but the crotch area is spaghetti, and the arms just as bad. In fact, even when I print with supports the outcome is similar.

Tried with Cura first, which is what I typically use, then tried again with Slic3r.

this was sliced in s3d, .15 layer, 215c pla, 3 oulines, 1500mm/sec speed.

[img]https://lh5.googleusercontent.com/-vYE8 ... 222900.jpg[/img]

as with any slicer, each will require a bit different settings to get the optimal print.

If things are getting mushy, i would try turning down your extrusion multiplier or double check your filament diameter.

overhangs are hard, but on an object this small depending on layer heights you could easily be printing in open air and that's no good.

Thanks for taking the time to print it out. I'll try with again with PLA, this one was done in ABS. Just been having a frustrating, bad day, and I realized that since I purchased my printer I've only printed parts to try and make it function better, haven't actually had a chance to use it and be creative. I think the majority of my frustration came with my failed dual hotend setup (having spent enough on it to have been able to buy a printrbot or other cheapy printer on the side!).

yup keep it simple, if your machine is mechanically sound stick with a single slicer and get your prints perfect. only if you are ready for a headache would i change anything away from the stock Rmax. I have never used Cura, slic3r was working good (until i started to slice for dual materials) kisslicer is good also.

Well, the reason I've been upgrading is because I've been unhappy with prints... mainly issues with overhangs. I very much wanted a dual extruder setup for supports. So many things I want to work on that are just too complicated without, and I'm not a fan of gluing plastics.

The upgrades I've performed have all been to improve print quality really. The reason I switched to Cura was because Slic3r was giving me really bad gaps and other issues. Cura did a better job, and was much faster.

alrighty so i just read your other post about print quality, i wouldn't worry about overhang if you aren't even able to get it to print the basic layers correctly. From what it sounded like in the other post back in May some of the other users on the forum were waiting for you to change some settings in the firmware and reflash. some of the settings aren't configurable in EEPROM and can only be changed within the program and recompiled/flashed to RAMBo. At this point its probably best to step back, breath and start over from the manual. If you machine is stock you should be able to get the seemecnc guys on the phone and they could help also. it might be worth it investing in a dial indicator to help with bed2nozzle distances.

The previous problem with the massive gaps had been resolved for the most part... it does involve me smashing the filament into the bed, but yeah, I did go through the firmware when I was working on the dual extruders. I changed several things, but I'll go through again... still, this is what I mean, constant, neverending tweaking to get it to perform adequately... fruuustrating. You're right though, time to step back and take a breather.

smashing the filament into the bed is not a solution.... honestly it doesn't look like your effector is traveling along the desired path... and that happens to be the most important thing in overhangs is building up from a good base.

atoff, what is your current configuration? Dual E3D extruders with RAMBo and the latest Repetier firmware?

Were you able to get good simple prints like the calibration cube at any point?

The "trick" with 3D printing on any consumer machine is to nail the basics. If you can't print a decent simple cube and have it come out nice looking and the correct dimensions, you'll have no chance with anything more complicated! The other thing to keep in mind is that a lot of the STLs out there were designed by neophytes who really don't understand how to design for plastic extrusion printers. If you need support for instance, I personally think it is a disaster waiting to happen to let the slicer attempt to figure it out for you. Even S3D has it's support issues. It is much better to learn to use a CAD or STL editing app to place supports where they makes sense. A perfect example of this is Johann's new ball bearing carriages for the Mini Kossel. It has integrated Z like support that literally zips off the part. There is no other way to make a part like this with the required precision. The fact is, the current generation of Slicr3s do not provide the tools or sophistication needed to do non-trivial things. In the machining world, the CAM application is often the most sophisticated and expensive app in the tool chain - it's where the cutter hits the metal to paraphrase the old "rubber hits the road" saying!

I know a lot of folks don't have an interest in designing or modifying parts, that's fine. It will take some time but I see a future (soon) where designers will "get it" and start designing in necessary support structures, etc. Johann's example is a good one.

All of this said, the part you are attempting to print has more issues than just support/overhang issues that need to be addressed. Have you nailed prating the single perimeter calibration cube?
I slice this using a scaled Z so I don't have to wait to print the entire thing. Something like 8 layers should be enough to know if you have it right. Search here for "single perimeter" and there are details on how to proceed. Now, if you've already done this in the past and were satisfied with the results, I recommend you go back and try it again. There are lots of little tweaks possible to really improve things but I have to say, the photo you showed yesterday has much larger problems that should be easy enough to track down and correct!

Cheers,
Michael

I was going to say much the same as MHackney, if you can't get good quality with cubes and cylinders everything else is wasting time.

My favorite print to dial things in is two cylinders, I'll print one to check layer alignment and consistent extrusion, then I'll print two on the bed because I want to set up retraction.
Even if you get that dialed in, small prints, severe overhangs and small details take some messing about, but at that point it's mostly about temperature and cooling.

Use a smaller nozzle. I never got perfect prints until I switched to a 0.25mm. Parts look almost like they're lathe turned from the grooves, and overhang performance is way better with smaller nozzles. The retraction marks aren't noticeable either.

Smaller nozzle = better quality
Bigger nozzle = faster prints

Generic Default, I absolutely agree with your assessment of nozzle size vs quality. But until one has nailed printing with a .4/.5mm nozzle attempting to print with a .25mm nozzle will be a frustrating experience. Once you are comfortable printing good quality parts with a larger nozzle, then the learning curve for a smaller nozzle is a lot lower.

cheers,
Michael