About to go "RAMBO" on my Rostock Max - Frustrated

[longshot]

Yeah yeah, its a pun. I met my quota for the year so don't worry about anymore.

Ok so I'm extremely frustrated at my Rostock. Like many others here, the setup has been nothing but one thing after another. I'll start from the beginning so folks don't assume I've done something dumb like forget to plug it in or something:

Specs: Rostock with Rambo 1.1
Round heated plate (Onyx) and Glass (ordered from seemecnc)
Added Tricklaser's ball bearing carbon fiber arms
Using Repetier (sp?) 0.80 - Stable
Printing: PLA (Blue) 1.75mm
Stock Extruder
Stock Hot End - 0.5
Power Supply Stock
Hot End Temp: 195C
Hot Bed 60C
Layer height 0.2
First layer height 0.3

Calibration:
PID checked/tested/calibrated the heat bed and the hot end.
Did the trick with the piece of paper, looks good, adjusted endstops, paper grips but does bend or pinch with everything hot.
Glass bows up in the middle when heated and adjusted Printer radius
Redid the z axis and Printer Radius with good results
Checked extruded grip on plastic (enough to pull plastic,
Checked extruded steps (within 0.5mm)
Checked extruded plastic width (per extruder multiplier) is calibrated (0.5 +10%)

Printing surfaces tried:
ULU Glue stick
Painters Tape (scotch blue)
Acetone + Glass

Problem:
I can't get a darn thing to stick. I can print calibration cubes to print all day long but I can't print anything else. I don't have stiff arms because of the ball bearings and I've added rubber bands to prevent backlash. So everything is highly repeatable.

So when it starts to print, the outside perimeters (test perimeters), takes a little bit of time for the plastic to start to extrude. I'll see little blobs here and there and eventually a nice even lines starts. It finishes in about 3 passes and then on to the work piece. So the first line isn't a problem, but when it picks up it'll leave a little plastic wisp, and when the hot end comes back over it, it'll melt and pick up the entire layer and thus destroying the piece. Sometimes I get a good layer and then it just doesn't want to stick anymore, balls up on itself as the plastic extrudes, the ball of plastic becomes molten, picks up anything including the entire next layer and destroys the work piece again. What I end up with is a of molten plastic and constantly cleaning the hotend.

I have no idea what I'm doing wrong . . . I've looked through these forums endlessly and every frustrated post, i have tried such a solution to no avail. Please help, about to toss my awesome Rostock in the trash. I'm just not getting anywhere.

[cambo3d]

that's a long description for not be able to get your print to stick...

"Glass bows up in the middle when heated and adjusted Printer radius
Redid the z axis and Printer Radius with good results"

printer radius is not meant for this purpose. if your heatbed is bowing find another solution.
what kind of glass are you using. glass should not bow in the middle. Heat bed will bow but not the glass.


Second.
what are you using to get your prints to adhere to the printing surface?
Most people use abs juice (acetone with abs filament mixture) with abs filament., blue painters tape or pva glue or hairspray with pla.
so what are you using?

third.
do you have the proper z height set for good first layer adhesion?

[longshot]

Thanks for the quick reply, I tend to be a bit verbose in my posts because limited information seems to be a cause of a lot of back and forth in the posts i read. I do appreciate you reading through it ...

1.

printer radius is not meant for this purpose. if your heatbed is bowing find another solution.
what kind of glass are you using. glass should not bow in the middle. Heat bed will bow but not the glass.

Ok then I got a big problem. The glass is borosilicate, matter of fact i ordered it through SeeMeCNC.com. the glass is held in 3 places using the clips supplied. I can only clamp it in so many places because of the wiring on the far end of the plate.

So the procedure is to check the home position at Z0. If its high or low I adjust the Z height. Then I check Z at each pylon and adjust the end stop screws till the little paper slides without pinching. When I re-home the paper pinches really really hard at Z0, which tells me that the glass/surface is warped. If my logic is flawed, please tell me. As a result i adjust Z height and print radius for the curvature found.

2.

what are you using to get your prints to adhere to the printing surface?
Most people use abs juice (acetone with abs filament mixture) with abs filament., blue painters tape or pva glue or hairspray with pla.
so what are you using?

Stated it above, I've used Glue Sticks on Glass, Painters Tape, and Acetone on Glass. The blue painters tape seems best and I can print calibration blocks till I'm well . . . blue in the face. (promise last pun). Never tried hairspray or abs juice (since i'm printing PLA)

3.

do you have the proper z height set for good first layer adhesion?

Maybe I'm nuts here but isn't that the whole point of the paper slide trick? If there's another procedure i should be doing, please for the love of all that is holy . . . enlighten me.

Thanks a bunch.

[Batteau62]

Why are you heating the bed for PLA? Doesn't really need to be. I don't print PLA on my Rostock but I do print it on a Printrbot jr. which has a wood surface covered with only blue painters tape. You do need to clean the tape with rubbing alcohol before you print. Have you tried PLA other than the "blue" you mention? Maybe it's bad filament?
Pics or video of your attempts might help with a diagnosis.

[JohnStack]

ibid Batteau.

[Polygonhell]

So the procedure is to check the home position at Z0. If its high or low I adjust the Z height. Then I check Z at each pylon and adjust the end stop screws till the little paper slides without pinching. When I re-home the paper pinches really really hard at Z0, which tells me that the glass/surface is warped. If my logic is flawed, please tell me. As a result i adjust Z height and print radius for the curvature found.

No it tells you either the surface is not flat OR more likely that the printer motion is domed, which is what adjusting the printer radius is there to correct for.

[longshot]

Batteau62 and JohnStack - i'll try to get some pictures and or videos of my attempts.

You make a good point on the PLA but the manual says to keep the plate heated at 60C for PLA and as high as 110C for ABS. So naturally I'm thinking yeah i got to keep the plate at 60C. I will give that a shot when I get home.

Bad plastic? Is there such a thing?

Polygonhell:
No it tells you either the surface is not flat OR more likely that the printer motion is domed, which is what adjusting the printer radius is there to correct for.

Makes sense either way I have to use the Print Radius to correct for it. If I'm using it wrong let me know, or if there some other mechanical way of adjusting for it.

[longshot]

OK tried it with no heat in the heat bed. Blue Painters Tape and rubbing alcohol to clean. Results are mixed. Looks like the results are better. Definitely huge leaps beyond the craptastic prints before, but still no dice.

I'm attempting to print this: Its a fan made with a bunch of support risers to keep it upright. They about 1-2 mm apart and are prebuilt into the model so there's no real adjustment there. It can be found here on thingiverse: http://www.thingiverse.com/thing:110305
Its made for the rostock max so I'm thinking it should be printable by one.

[img]http://i1303.photobucket.com/albums/ag155/longshot114/IMG_10561_zpse9805d88.jpg[/img]

Here's the picture of print:
[img]http://i1303.photobucket.com/albums/ag155/longshot114/IMG_10551_zps8f93deff.jpg[/img]

So I'm thinking it might be retraction, but I've tried multiple values. I'm not sure on speed either. Current settings:

Retraction: 1
Z lift: 0.2
Speed 20
Extra Length on Restart: 0
min travel on retraction: 3mm
Retract on Layer Change: yes
Print Speed 175mm/sec
Everything else is set to 20mm/s
External Perimeters is at 80%
Extruder Multiplier: 0.6
Infill: 0.1

What about print speed? Do I need to increase flow? Am I starving the extruder?

Thoughts? Comments?

[foshon]

I think you should increase your hot end temp by 5 degrees at a time, see if it helps. I would reduce that print speed until you get a feel for printing, I would try around 50mm during the first few prints. Also, bowden retraction with the original hot end is tricky. To get the speeds right and not clog the hot end you'll have to have a fan blowing on the peek insulator.

For now I would recommend trying a few smaller prints that print quickly. I would also turn off retraction until you get the extrusion figured out. IIRC, in the end you'll need around 7-11mm of retraction to stop stringing.

[jesse]

Get rid of the tape and use PVA glue stick.

[img]http://i.imgur.com/wy1FLrO.jpg[/img]

Another option is hairspray

[Batteau62]

I'm with foshon on this one. Play with temps,(Verify temp at the hotend with multimeter thermocouple thermometer), slower speed, turn off retraction, install a Peek fan(if you haven't) and a fan for part cooling. I would also advise an upgrade to an ezstruder, the stock one was nothing but headaches for me.
Also, in your pic of the print, how many layers is that? Do you get a good first layer?

[geneb]

I've got 160+ hours printing with Orange Menace so far, and I use a 10:1 mix of water to Elmer's white glue in a spritz bottle, right on the glass @55C. Zero adhesion issues. I'm running a LOT of SeeMeCNC's translucent PLA at 190C - mostly because I run it pretty fast, but it couldn't hurt to try tweaking your extrusion temps as suggested.

g.

[longshot]

Foshon:
I think you should increase your hot end temp by 5 degrees at a time, see if it helps. I would reduce that print speed until you get a feel for printing, I would try around 50mm during the first few prints. Also, bowden retraction with the original hot end is tricky. To get the speeds right and not clog the hot end you'll have to have a fan blowing on the peek insulator.

For now I would recommend trying a few smaller prints that print quickly. I would also turn off retraction until you get the extrusion figured out. IIRC, in the end you'll need around 7-11mm of retraction to stop stringing.

I would think increasing hot end would be counter productive. The problem is the plastic seems to stay molten just a tad. As the head passes over the previous layer, it'll pick up the old stuff and mess up the work piece. I will try it. But wouldn't a higher temp make things worse?

The PEEK has a fan on it from the very beginning. I read the fan post stickies at the top of this forum and understand its importance.

As for smaller prints. I have printed about a dozen calibration cubes with no issues. I have another dozen thin wall tubes to get e-step and extruder calibration correct. All can be done with very little problems.

I'm second guessing the retraction. Setting it at 0 for thin wall cal squares is one thing but when i got to make a bunch of perimeter jumps I would think a more aggressive retraction is needed. I do notice that it does dribble in a few spots. . . am i starving the hot end?

Jesse:
Get rid of the tape and use PVA glue stick.

Geneb:
I've got 160+ hours printing with Orange Menace so far, and I use a 10:1 mix of water to Elmer's white glue in a spritz bottle, right on the glass @55C. Zero adhesion issues. I'm running a LOT of SeeMeCNC's translucent PLA at 190C - mostly because I run it pretty fast, but it couldn't hurt to try tweaking your extrusion temps as suggested.

I can try it again with the glue stick (this time with a non heated bed) and elmer and water mixture to see if that gets me anywhere. I'll also play with the temps. Thanks, Geneb for responding!!

Batteau62:
Also, in your pic of the print, how many layers is that? Do you get a good first layer?

2 layers. The first layer looks decent but has some blobs and small strings here and there. I think its the darn blobs that get caught on the hot end and dragging whatever its connected to.

[barnett]

I agree with the other advice (regarding temps, retraction, try simpler prints; how about the calibration pyramid?).

But you also might try bumping your z height up a smidgeon (making z=0 slightly closer to the surface, maybe +0.03mm for starters). I found that the filament sticks better when I squash it down on the tape. Just don't crash your nozzle.

[lordbinky]

You could always try different sets of calibration objects, like this retract calibration one.
http://www.thingiverse.com/thing:101056

I can't see the pictures so my response may have slightly originated completely from my imagination.