General 3D Printing Thread


 
reprap.org has tons of information including information on specific printers (prussa, mendelmax, taz, etc). Grab the beginners guide (http://reprap.org/wiki/The_incomplete_reprap_beginner's_guide)
alot of your questions will be answered in there (only to spawn new ones!)

reddit has 3d printer forums and earlier this year Misumi ran a deal where you got $150 off your order (regardless of size of order), lots of folks got
their aluminum extrusions from them.

Great hobby, and works really well with this one! I'm currently printing the case and I've made a square blower to 1.25" round transition to attach my blower
to round conduit that I have attached to my smoker. I'll be building the more sophisticated ones posted here soon too.
 
Well I got my borosilicate glass yesterday and I went from this (bare aluminum plate)


To this with the glass on it and clipped down at 4 points


I tried clipping it down with just 2 clips at the front, which should theoretically "tripod" on that hump in the middle. However, when I go to print there are still parts where I start to get infill so thin that it looks like the head is touching the bed and it starts to strip out the filament because it can't extrude any more. My first layer is 0.30mm indicating this is a pretty big hump. I'm not 100% sure that's what's happening but I start getting wicked thin infill and you can see the hobbed bolt cutting chunks out of the filament as it attempts to feed it.


There's gotta be something I'm missing here because the glass should theoretically be more or less flat. If the bed wasn't orthogonal to the extruder, then you should see it getting worse and worse the further in that direction you go. However, it's worse in the middle and works better as it moves outward. It is almost like both my X and Y axes are bent but that's almost impossible given their construction (the Y axis is supported at 4 points on two rods, for one). I'm am running flat out of ideas here, the only thing I have left is to try to lift the glass up 1/2mm on the 4 corners and see if it starts to sag or level out in the middle.
 
Your glass is conforming to the plate. This is why I used thicker glass when I used to use glass. Try fabbing 4 corner brackets that can raise the glass.
 
Are you able to set your z home extruder nozzle to print bed gap with the nozzle sitting at the high point of the bed? That should start the print high enough to prevent the filament strip. Based on your plot, you only have around 0.1mm of hump. You should be able to absorb that much error in the first couple layers of the print.
 
The TAZ suspends the glass and heater above the AL bed. That allows you to level the bed and gives you a little spring if you move the z too far down. You might be able to incorporate something similar.

You can get the bed corner and bed finger stl files here: http://devel.lulzbot.com/TAZ/2.1/production_parts/printed_parts/stl/

corner.JPG
 
Are you still running the PCB style heater? I'm guessing not, cause the pcb board heater definitely conforms to the glass rather than the other way around. If you have a silicone heater affixed to an aluminum plate instead and the glass has to sit right on the plate, your aluminum plate better be flat, seems like it isn't... Maybe sand it down or flip it over? Or move back to the PCB heater that sits above the plate....
 
It seems the glass is conforming, but if it is only clamped down on one side, shouldn't it just form a ramp that goes up 0.138mm in the middle and up to twice that by the end? I would think without clamping the other end, it would just form a plane that's not perpendicular to the extruder which would be fixed by the bed-leveling code. Instead it seems just as bad. I print with 0.24mm layers and this first layer is 0.32mm. If I back the Z-axis off by 0.15mm then the perimeters around the outside are way wrong, round and have trouble sticking.

My glass and heatbed are already suspended above the Y axis and I've checked to make sure that it isn't making contact in the middle which could be flexing it up.

It's not the bed-leveling code either because the plots above are with 0 correction. I get the same results with or without doing the leveling probes.

It just seems to me that if you have a piece of aluminum, suspend it loosely from the four corners, and put a weight on it (3mm boro glass) it should sag down in the middle not bow up. The original PCB heatbed also had the same shape. I feel like there's something fundamentally wrong with my build that's causing it across every configuration (3 different types of Z-endstop, 4 different beds) I've had because the only constant is the machine.
 
Rub your hand down your smooth rods and see if the linear bearings cut grooves into the smooth rods in the middle. I noticed that starting to happen on my y-rods and that was one reason why I moved over to pillow bearings. If so, perhaps rotate the smooth rods a bit so the bearing ride on a different part of the rod if that is the case....
 
Anybody got an opinion on the daVinci 1.0 ? For $500, it looks like a good start. I've already found how to defeat the need for cartridges & how to put Repetier FW. I'd be willing to spend more to get more, but I don't think I could put together parts for 700 to do what the daVinci is capable of. Id still need to tinker, might as well start from a 'standard'

Talk me out of it.
 
I don't have any first hand knowledge of anyone using it, but my biggest gripe would be the cartridges. If you have a way around that, then it seems OK.
 
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Anybody got an opinion on the daVinci 1.0 ? For $500, it looks like a good start. I've already found how to defeat the need for cartridges & how to put Repetier FW. I'd be willing to spend more to get more, but I don't think I could put together parts for 700 to do what the daVinci is capable of. Id still need to tinker, might as well start from a 'standard'

Talk me out of it.

I have one, you are correct the cartridges aren't as big a deal as everyone makes them out to be. For the most part they are cost effective with a cartridge being only $28 shipped from amazon prime. I too am running a hacked management software that doesn't even use the counters in them. There is a forum dedicated to it that has a hacked version of the software that allows you to load straight g-code from slic3r.

My complaint would be I can't get the thing to print accurate curves no mater what I try. The heater meter cases have been no problem, and random shaped things are fine. For instance there is a twisted star shaped vase 'demo' print built in that comes out great. However, if you want a precise circle or curve (I am currently prototyping my own damper system) it isn't accurate enough for what I want to do. This seems to be partly down to how belts work and the adjustments available for truing it up. And partly down to the plastic shrinking as it cools. The first problem makes it consistently off, which is why odd shaped things come out ok. The second is quite unpredictable and I have started experimenting with various starting and ongoing bed temps to try and address it.

Maybe my expectations for accuracy are too high, or maybe the problems I am having are just part of 3d printing. All in all, you probably can't beat the opening price for getting into 3d printing without having to build your own machine.
 
I have one, you are correct the cartridges aren't as big a deal as everyone makes them out to be. For the most part they are cost effective with a cartridge being only $28 shipped from amazon prime. I too am running a hacked management software that doesn't even use the counters in them. There is a forum dedicated to it that has a hacked version of the software that allows you to load straight g-code from slic3r.

My complaint would be I can't get the thing to print accurate curves no mater what I try. The heater meter cases have been no problem, and random shaped things are fine. For instance there is a twisted star shaped vase 'demo' print built in that comes out great. However, if you want a precise circle or curve (I am currently prototyping my own damper system) it isn't accurate enough for what I want to do. This seems to be partly down to how belts work and the adjustments available for truing it up. And partly down to the plastic shrinking as it cools. The first problem makes it consistently off, which is why odd shaped things come out ok. The second is quite unpredictable and I have started experimenting with various starting and ongoing bed temps to try and address it.

Maybe my expectations for accuracy are too high, or maybe the problems I am having are just part of 3d printing. All in all, you probably can't beat the opening price for getting into 3d printing without having to build your own machine.

Have you seen this?
http://voltivo.com/forum/davinci-hw...-circles-aren-t-round-check-this-56k-warn#276

I wouldn't think it'd be inherent in the design, probably mfg tolerance or something wonky in the movement.
I think I'm going to grab one, but i'll wait till christmas time - see if there's any deals to be had.
 
Andy, I did see that, and some of the threads on that forum are where I have figured out how to do a lot of my tweaking to the printer. I haven't printed enough that things would be worn out, at least I don't think so. I haven't even gone half through one of my cartridges. Overall I am happy with it, and I think that tinkering is part of 3d printing no matter what route you go. To me it seems that any 3d printers with belts are always going to have some amount of slop. I saw a pellet fed printer on kickstarter that used all worm drive screws, which seemed like a good idea for precision. Way out of my price range though.

Da vinci also just came out with the dual head one so you can print two colors at once. Its not much more than the single head.

If you get one let me know if you figure out any good modifications. So far I have just used the software hacks to be able to use slic3r and g-code from the management side on my computer. I haven't had to modify the firmware or anything to do that.
 
My Reprap 3D printer is alive. It came as a full kit from China and it was pretty straight forward to build, even with the Chinglish build manual. It only took me two evenings to complete. The wiring is still a mess but at least it's printing.

ReprapPrusai3-2.jpg



Small objects come out fine. (The dots on the 15mm calibration cube are my sons idea ;) )
ReprapPrusai3-3.jpg


But larger objects have these cracks, and I don't have a clue how to get rid of them;
ReprapPrusai3-1.jpg


Some help from the 3D print gurus here would be greatly appriciated. I am using PLA, the printbed is 65C and the extruder is set to 193C.
 
Nice looking machine Peter! The broken layers don't appear to be in any regular pattern so I don't think it's a leadscrew issue. You appear to be having intermittent extrusion problems which could be coming from any one of several sources.

1. hotend temp: is the hotend hot enough for smooth extrusion? PLA has a huge range of temps and I'm often in the 210C range. Conversely, is your hotend too hot and are you having problems with heat creep that could be causing jams?
2. Speed: Are you printing too fast? What are your speeds like for infill/perimeters? Printers can travel much faster than extruders can extrude
3. retract settings: are you using retraction? Too much retraction can lead to jams when extrusion restarts
4. Filament: More and more filament suppliers are coming online everyday but the fact of the matter is that not all filament is created equal and some just suck

Start with these and see what you get. The prints are looking quite good for your initial tests and you have to be the most focused person in the world to get a printer together in 2 nights and have it working already. Great job and welcome to 3d printing.
 

 

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