MartijnvG

wow i haven't been on the forum for quite some time. But i'll introduce myself: I'm Martijn, 29 years young, started working at ultimaker 6,5 years ago. Fulfilled all kinds of positions within the company at a lot of different departments. Ended up at R&D as a project engineer, and am now responsible on helping to improve processes within the R&D department. As well as still doing the occasional hardware development. My hobby's are Climbing (Bouldering mostly), Video games, D&D and drinking beer (the last to can be very nicely done together). Like i said before, it's been a long while since i posted here. i'll try to start doing that more again. Edit: @SandervG heeey where is my Team ultimaker badge ?

woooh david we love you

hmm, maybe i'll make a small vid tomorrow and post it here if that is ok.

Another way is to drop it through platform in Cura. It will only print the part that is above the platform. Then remember that value, flip the part and drop it the total height - the remembered value. And if you are on win10 the 3d builder app has a similar option and works quite well.

good to see i'm not the only one hit with the double reply bug. secondly, Back to the drawing board my dead watson! Hehehe i covered it up by just typing some extra stuff

Just make sure you don't heat up the water to more than 35C because that can cause to deform the PLA.

ooh and i should update my printer profile right?

Wait, where we not building a giant 3d printing robot spider for world domination?

didn't he fry his last board?

cool! i would love to see a turbo fan version. I would be very careful with cooling the nozzle more then 10C this can possibly make it harder for the feeder to push material through and grind the filament faster, or prevent the layers from melting together properly and then loosing structural integrity or worse de-lamination. but i'm curious to see what you end up with!

cool i joined as drjackhol most of my time is spent on CS:GO but i'm thinking of starting some rallying on dirt rally

Hi Clamking I really like your fan-duct design. especially the flow simulations you provided next to the design. Having a close to symmetrical design would always be a preference. And the advantage of 3d printing is perfect in being able to perfectly guide the air to the nozzle as smooth as possible. But as the metal also doubles as a heat shield/ anti finger burner we made some choices in that area. One question i do have is why you have the airflow enter on the nozzle instead of underneath it? in my opinion you would be cooling down the nozzle here maybe a bit to much, especially when actually printing and printing other materials then PLA. The simulation shows how the air would flow when the bed is moved all the way down. but this is rarely the case in actual printing. there is almost always either a complete or partial layer underneath, making the air flow differently. Discussions have always been going on with 3d-printers about what would be the perfect way to cool. Very concentrated around the nozzle (https://www.youmagine.com/designs/mkiii-clone-r1-active-cooling-duct) or general layer cooling (think of the big laminar coolers on the side of the machine https://ultimaker.com/en/community/4890-the-crossflow-fan-approach). We try to do something in between, cooling the model as well as cooling the material just after printing. but with the head moving all the time while printing and the height of the print affecting the flow and backflow of the air when out of the fan-duct this is always a very interesting balancing act. Keep up the good work! i would love to see more improvements/idea's.

I only intern of Fridays all the other days i'm just a normal r&d'er. @labern Is this the thanks i get for helping you with the fanduct

Second attempt 0,25mm nozzle 5% original size 0,04mm layers

.. it needs to be pretty too! Hahaha, hey give me some slack. first attempt here

First attempt have to fix the stringing. but this is at 5% normal hight 0,25mm nozzle from olssonblock

first prints detached from bed, rookie mistake. lets go again

He told me his max was this hand at 5% size. now i must beat him :angry:

i'm game

That is the question! The workaround is fine and I am happy to have a non-zebra shippy but it is only a calibration object. Sooner or later someone will not be able to just pivot things...and given they should not have to in the first place, it does seem a permanent fix would be nice! I think @Gr5 hit the nail on the head that the problem is in microstepping somewhere. now we need to figure out if its in the boards, firmware, motors or a combination of it. So it does have our attention. the question is how deep the problem lies. so only a quick fix for now. but i'll try to keep you guys posted.

hmm i did some searching, and it seems the issue is indeed in the fact that the 1th or last step in the microstepping seems to be un-event to the rest of the steps. i found an old thread about it. http://hydraraptor.blogspot.nl/2012/04/stepstuck.html we are using the A4988 chip i think so maybe this solution might be a nice way to fix it.

No @didierKlein it was not the infill. even withouth infill it still happens. it is the accuracy of the microstepping when a plane is close to either the x or y axis. we need to get rid off the idea it was the infill.

Yeah, the effect is because we try to print a line that is nearly parallel to one of the axis. If this the case, the resolution in the x-y motors becomes visible. As we rotate away from the axis and the line has an angle of 15° or more compared to either the x or y axis, the motor resolution becomes high enough and the effect becomes invisible. It's a bit similar as in this picture. where drawing the line at a slight angle makes it have jumps in it and when the jumps become small enough they are no longer visible.

Good work @Wisar ! this really helps us understand the pattern! hopefully other people can benefit from it as well

the switch to 90° should not make any difference as the stripes are an effect of the plane not being parallel to either the x or y axis, but have a slight angle to them. the striping is the motor doing a step to make that angle in the plane. the tests @Wisar is doing should show us at which angle (compared to the x axis the effect disappears). i'll try to setup a similar test tomorrow to try and reproduce it outside of the little boat test.