Fresh start (again) and too much of filament? (Deformation)

[tomulinek]

Hi, I just repaired my new Printrbot Metal Simple Kit with replacement bearings and rod (and also PC power supply) from Printrbot as the first version of assembly jammed completely because of rough bearings (see with 3Dbenchy distorted before repair and disassembly).

So, I am on the start line again – and my first prints with rebuilded kit looks… Different. (Picture.)

Question for advanced Printrbot users: There is bunch of problems, like the 1st layers with corners rounded up even on raft(!), some solid walls are distorted, surface is not without small random slopes… Do you see something already resolved by you after callibrating new machines? Thank you for tips in advance.

PS: Yes, fan shroud is functional.

[Chris Knowlton]

Tom,

It looks like you are getting close. First I would eliminate the raft. Unless your bed is really out of level it should not be necessary. Then if you are having issues with your parts curling up at the edges I would use a brim. That should take care of the radius you are seeing with the first layers. Make sure you are getting a good “bedded” (flattened) first layer.

Based on the excess of material on the top surfaces of both parts it does look like, as you mentioned, you are over-extruding a little. I would reduce the extrusion rate or check your filament diameter setting.

I expect that the deformation on the right pillar, because it is a little smaller than the other two pillars, is due to too much heat. Fan on high would help. Try using a rectilinear infill which will give the walls a little time to cool before the infill is added. If you have the option use inside-out printing. For this piece you might also try slowing down the printing speed.

Chris

[cacb]

I have the same printer and heated bed. I agree with the comment about the raft, try without it. I have no PLA curling with the heated bed. Try possibly 185C, measure filament diameter/reduce flow rate and make sure the fan is on (seems to be from your picture).

[tomulinek]

Thank you both, I will try to follow your tips. As I fight with original orange kapton foil with PLA, I will also try to abrade it a bit (to matt surface) and will slow down the 1st layer. I have also bought black matt kapton which should be more adhesive.

[Mooselake]

Consider using gluestick (or hairspray, sugar water, etc.) to improve how well the plastic sticks to the print surface if you're having problems with the first layer curling. Many of us pioneers have abandoned Kapton for gluestick, etc. on glass or just the current aluminum print bed.

Rafts were used with the early reprap printers before they started using flat and level (referenced to the extruder, not the planet earth) print surfaces with a carefully set nozzle to print surface clearance. In most cases today rafts are a waste of plastic, and not used very often.

Kirk

[frankv]

Hi Tom,

Did you try painter's masking tape? I've had good results with it, both the blue stuff that everyone raves about, and just as good is cheap white stuff. Make sure that you wipe down the surface immediately before printing to remove any grease/oil/whatever. I use methylated spirits (alcohol) for this.

[cacb]

[tomulinek]

Hi all, thank you again for experienced advises. I know the blue tape (or squares) from MakerBot 5th gen. well, but it is not perfect (problematic 1st layers and impossible removal of bigger prints), so I decided for heated bed for my Printrbot Kit. Glue on glass is the best way, but original heated bed from aluminium has orange/brown kapton foil. Which is not bad, but not 100% for me yet. Hair spray is too messy and glue sticks doesn't work as well as on the glass. Technical alcohol for cleaning is very fine before every print and the real magic of kapton is easy removal after the bed is cooler. But on Czech RepRap forums (we have an active community here, not only because of famous Mr. Prusa ) there are good mentions of matt kapton foils. So I have bought them as a spare parts and will see one day...

PS: Sorry for my weird English.

[cacb]

[tomulinek]

Adhesiveness now works: I did it three things which seems to be right. 1) Kapton foil is sanded (more adhesive; but I did with not proper sand paper, so it is more scratched yet). 2) The 1st layer has only 50% of print speed. 3) I am more aggresive with Z- values (nozzle is nearer to heated bed). And the magic: Normal prints stick well (knock knock).

Plucking: On the side of the models which is hidden from my fan shroud by nozzle there is still deformations up and plucking (if it is the right term). So I've decided to print the round shroud around the nozzle – . Some say it is better from this point of view and I hope my Printrbot Simple Metal can achieve nice looking overhangs (as it did in Make's magazine 2015 test).

[tomulinek]

My fight against overhangs is still not won. I know Printrbot Simple Metal can print much better.

2015-06-14 16.49.38.jpg

As this thread starts to be a bit out off topic, I moved the theme of overhangs here – with new pictures of direct duel of Printrbot Metal Simple vs. Makerbot 5th gen:

[cacb]

[ktfergus]