folgertech 2020 Pursa i3 first prints and questions

Hi, all. I brought a forgertech 2020 Pursa i3 and I finished the build two days ago. I was struggling with X-axis homing issue, but found solution at the printer official thread --[forums.reprap.org]. Later on When I was trying to calibrate the extruder, I realized the extruder motor pins are reversed in the built guide. So I fixed it and successfully calibrated the extruder. Here are some pictures of my first few prints-- two single wall hollow box and three end stop mount.









They are not too bad for the first prints, but as you can see that I am suffering from the ripple-line and small gas between layers. I know I still need to tune the printer for better prints, but can someone enlighten me the causes of these artifacts? I heard that the ripple-lines could be caused by the small vibration in X and Y movements, but I am not sure about it.

Also, i tried to follow the calibration guide on reprap wiki, there are some terms like 'perimeter width over thickness', 'extrusion feed-rate', 'bridge feed-rate multiplier'. Where can I find all there parameters if I need to change them? Is it inside the firmware or software? I am using repetier host with built-in slic3r.

Thank you in advance, and please let me know if you need extra information.

I'm sorry I can't help diagnose the issue (I'm facing much the same issue on mine). Can you tell me what guide you followed to calibrate the extruder?

I followed the guide on [www.instructables.com]. The extruder motor pins are not corrected on the built guide, and I reversed it. here is a pic of correct one.

The waviness looks like z wobble to me, Are your 5mm rods bent slightly? What are you printing, ABS or PLA? What temps are you using?

I would go into the Folger Tech google drive and use their configuration manual. I've been running those settings for the most part. What layer height are you using? It looks like like it might be a little tall from the pictures.

Hmm doesnt look quite as good as my first prints. I would say get your Z end stop perfect. Start in the middle of the plate, and get your hot end so close in the home position that it lightly drags on a piece of paper. Then move it to each corner and use the screws in the bed to make them all that same distance from the hot end. Then move it to the middle and double check/make slight adjustments to the end stop. The main point is getting the bed as level as possible and get the Z end stop right. It does look like your layer height was thrown off by bad Z axis calibration and was printing from too high up. Thus creating that separation/solid line type extrusion. The Zig Zag is probably Z wobble as mentioned above, but that will probably also be reduced a bit by getting that Z axis closer, but wont go away entirely until you adress the cause of it.

I also think you could fine tune that extrusion some more. Maybe try some different temps, but I think most of the reason your extrusion looks bad is Z calibration.

I am no expert but I got mine printing really well already having built it on saturday and my prints look like this:

My first 3 prints: [imgur.com]

How my prints look now with proper extrusion and Z calibration : [www.thingiverse.com]

Edited 2 time(s). Last edit at 06/30/2015 10:34AM by mel0n.

I was using 1.75mm PLA with temp 185/70 for those prints. The layer height was 0.4 and extrusion width was default in rep host.I read online that lower layer height and lower acceleration could help, so I changed the layer height to 0.2 and extrusion width to 0.5 with x/y acceleration to 500. Now I do not see the ripple lines anymore, but new artifacts was introduced. Sorry that I am currently out of town and could not upload any picture here. I will try my best to describe the new artefact here. For the 0.5-thin-wall hollow box, it looks like there are changes of extrusion width or slightly direction variation every few mm on both x-axis and y-axis. In the end, I have these diagonal lines across all four walls. and if you touch it, you can feel all these bumps on the wall. I was think that it may be caused by a clogged hot end, so I disassembled the hot end and cleaned it, but the artifacts still exits.

Mel0n, thank you for your advises. I will re-level the bed when I go back, but I think my bed is close to level. You mentioned extrusion calibration, could you be more specific on that or direct me to some reference? I also noticed every time when it was extruding the extruded material tend to bend up and stick to the hot end and created a mass down below. I have to kill/restart the print. I believe this is a extrusion problem, but still not be able to identify the cause. Do you think that the flow-rate could be a cause? if so, how do i tune these parameters.

Heres a quick how to for your extrusion [www.youtube.com]

Works great for me, I still believe yout z-axis is off. Mine curls up when it oozes but thats a property of PLA so if thats what your using thats normal. I would play with your temps on some small cubes and see if you can get some improvement there as well. If your getting the curling up while printing I say that your x axis is too far up and possibly temps. What are you using for layer height?

Edited 1 time(s). Last edit at 07/02/2015 02:56PM by mel0n.