Page 1 of 1

First prints questions

Posted: Thu Apr 28, 2016 7:03 pm
by Cosmeo
Allos, I guess this is my obligatory "Look at what I made mom!" post.

First off thank you to everyone on the boards I've learned a lot here just by reading posts and thanks to makergear for making such a nice printer.

So I started with the bracelet like probably everyone does and it printed well (slight corner bulge) and then I moved on to printing Jules new tool attachment (Your awesome btw if someone hasn't told you today).
But I have a few questions about how the print came out. It bulges out on corners, doesn't seem to fill properly and first layer it takes a second to extrude out enough to stick to the plate till then its just a couple of dots, so far its sorted itself out when its doing the outline thing.

going to try and post a picture here but I'm kinda new at this and I'm old so..
https://www.dropbox.com/s/pwlwx93qph2y7 ... 5.JPG?dl=0
not sure how to make it display in the forum sorry.

So I went over to simply3d trouble shooting page and for the corners it says to hot and over extruding can cause that problem, but for the filling issue and the first layer it says under extruding is the problem. So since it dosnt agree with what I'm seeing I thought I would ask before I start messing with anything.

Also is there some good test items that people print to calibrate too?

Re: First prints questions

Posted: Thu Apr 28, 2016 9:31 pm
by Jules
Cosmeo wrote:.....then I moved on to printing Jules new tool attachment (Your awesome btw if someone hasn't told you today).
I like you! :D
But I have a few questions about how the print came out. It bulges out on corners, doesn't seem to fill properly and first layer it takes a second to extrude out enough to stick to the plate till then its just a couple of dots, so far its sorted itself out when its doing the outline thing.
What slicer software are you using? Simplify3D or Slic3r? Sounds like you might need to adjust your Startup script to make it purge before the print. It primes the nozzle and gets it ready to lay down an even thread.

That print looks very good.....the slight bulge that you see at the one corner is probably due to printing at too high an acceleration. (That's another thing you can change with the Startup script to slow it down a little.) Might be a little fast on the printing speed too - the default is really high. But it isn't going to affect the functionality of the toolholder and it's going to be hidden against the machine, so I wouldn't even bother to reprint it.
Also is there some good test items that people print to calibrate too?
Yep, because it takes so long to print and check and print and check.....the smaller the item you are testing the sooner you finish. Ed came up with a little 2 mm calibration square that I have printed literally hundreds and hundreds of......and as he likes to say, "If you can print a thin-wall calibration square, you can print anything." (Or something along those lines.)
calibration.zip
(1.98 KiB) Downloaded 460 times
You've gotten off to a great start....(be sure to read the Beginner's Guide in the How To forum if you haven't yet). The rest is just fine tuning. :D

Re: First prints questions

Posted: Thu Apr 28, 2016 9:53 pm
by Cosmeo
I'm using simplfy3D, the purge is when it runs off the platform and extrudes for a few seconds if so then its already doing that.
Ill try slowing it down and see how it turns out on a few other things, I didn't plan to reprint the tool holder for the very reasons you said.

I've printed the calibration cube a couple of times, my height is spot on but for some reason one side is just a bit thicker. three sides will be .43-.44 and the side facing the back is .49-.50 its the same on both the prints I've done. I have to wonder if I messed up the height adjustment I might try running that again, tbh I had a time with getting the same "light resistance" during the setup.

Re: First prints questions

Posted: Fri Apr 29, 2016 1:02 am
by Cosmeo
Another question! Apprently I don't read enough because I couldn't find how much bite was supposed to be on the filament.
I changed colors so I retracted my filament, and this is the bite that was on it.
Is that normal or too much pressure on the filament?
https://www.dropbox.com/sc/f3y1vlntsid1 ... rVZk4Y0kla

Speed fixed some of the problems above namely the fat corners then I did the solid cube and the layers are not solid you can see space between each row, so now I'm off to see what I can find about that.

oh look its drink o'clock!

Re: First prints questions

Posted: Fri Apr 29, 2016 4:05 pm
by Jules
By the way....late last night I noticed a tiny hiccup in the starting thread extrusion as well, on the most recent version of the firmware for the Rev. E dual, so it might not be your purge. (The purge is that part where the nozzle moves off to the right side of the machine and drops about 20 mm of filament before every print, then wipes itself off on the plate.)

I usually just print with a skirt around the object, 2 or 3 outlines, at a distance of 2 to 4 mm, to make sure that the flow gets going well before the main print. That usually takes care of any problems. :D

Re: First prints questions

Posted: Sat Apr 30, 2016 7:06 pm
by Cosmeo
"Smile when your frustrated, that way no one will see how much you want to cry."

So I am still having problems. I have kept trying to dial in the settings according to the print trouble guide over at simply3d but they don't seem to be helping.

I kept at the thin wall box but never managed to fix rounded corner issue. I tried printing the hexa demo file but the bottom was still gapped on one side and the top again had thin filament that didn't fill in with the last couple layers pulling away at the corners.
IMG_1752.JPG

I re ran the platform leveling and it said it was level. I re did the starting height adjustment.

So I tried the full box and adjusted my extrude multiplier till the last two layers were filling in and making a solid top just up to .94, but the corners were still bulging out and the size of the box was 20.2.

Then I decided just to try and print something else and just see how it worked out. in simply3d I set the temp to 220 bed to 70 extrude to .90 speed to 3000 mm/min and printed the makey robot. That went really bad. by the first cm it started pulling up off its self. guide said not enough cooling and printing to hot. so I put a box fan behind the printer, dropped the temp to 205 and tried again.
IMG_1756.JPG
IMG_1758.JPG
IMG_1759.JPG
Those didn't turn out so well either. I dropped the temp again to 190 speed to 2400 and tried again. Same problems, bulging corners, warping on the over hangs.
I reprinted the demo pieces, bracelet comes out ok, Hexa comes out with gaps and top layers to thin.
I just don't know enough to know where to go from here.

Re: First prints questions

Posted: Sat Apr 30, 2016 9:51 pm
by Jules
Cosmeo wrote: I couldn't find how much bite was supposed to be on the filament.
That might be a just a hair too much tension on the Filament Drive screw....there's a write up on it here.
viewtopic.php?f=3&t=2694
Speed fixed some of the problems above namely the fat corners
I kept at the thin wall box but never managed to fix rounded corner issue.
It's not so much the printing speed causing bulging problems at 90°corners....unless the file is designed with a reverse dog-bone, corners always bulge a little with this kind of depositional modeling. (And I sure didn't bother with that with the tool holder design, it's not structurally significant.) You're squirting down molten plastic spaghetti, when the machine makes a sudden direction change, the plastic is going to bulge a little as it follows.

You can reduce the "ringing" effect of that a little, by making a hard coded change to the Startup Script to slow the Acceleration. (Not just the printing speed, although that helps too.)

This is the code, and you have to add it to the front of the Startup Script in S3D:

M201 X1000 Y1000 ; lower default accelerations

printing the hexa demo file but the bottom was still gapped on one side and the top again had thin filament that didn't fill in with the last couple layers pulling away at the corners.
You did the right thing checking the level and resetting the starting height on that hexa print. What you don't know yet is that most white filament is a pure-D-b*tch to print. It's the nature of the additives in that color or something, and it frequently thins out and sometimes stops completely. So don't be surprised or frustrated when it happens, just reprint.
I tried the full box and adjusted my extrude multiplier till the last two layers were filling in and making a solid top just up to .94, but the corners were still bulging out and the size of the box was 20.2.
You have the Rev.E version of the machine, right? That takes care of everything that a beginner needs to worry about, and all of the earlier stuff that was necessary for the other machines is not necessary for the Rev.E users. (Keep the extrusion multiplier at 0.90 for now.)

The disadvantage for the Rev.E users currently, is that there is not an easy way for you to dial in tighter dimensional accuracy with your machines at present. When the Z-Adjust app is finished, there will be.

But I really do think the thin spots in your prints are largely because you are printing in white plastic.
....printed the makey robot. That went really bad.
That is a small PLA print with overhangs and a small footprint. And it's warping because it's too hot.

1. You need to cool it off a lot.

Point a desk fan at it, (or take off the fan guard on the bed fan), print with support, and use adhesive on the plate.

2. Do not print the PLA at a temp over 205° to 210° when you have overhangs. (Lower temps are fine if you are getting good bonding between the layers.) Take the bed temp down to 55° to 60° and use adhesive. Hotter is not better with PLA.

The hotter you print PLA, the longer it takes to cool down, and the more warping will occur while it is cooling. (Once it cools down, it stops warping.)

3. Use support under the warp prone areas. (In general, not necessarily for that particular print. The overhang areas are small.)

This is all just learning the specifics of printing different kinds of plastic....there is a fairly complete write-up on printing PLA in the Beginner's Guide here:

viewtopic.php?f=3&t=3542

:D

Re: First prints questions

Posted: Sun May 01, 2016 1:22 am
by Cosmeo
Thanks for the advice, ill switch back to the black and print out a few things with these suggestions. Ultimately though ill be printing in white for several projects I've got in mind so I will have to learn how to make it work some day.
The tension came like that but I'm going to loosen it up a bit it seemed excessive when I switched it out.

As for the bed level, program says its level, done it three times each time it says its level and no adjustment is needed. But it just, I don't know, it doesn't "feel" level. Its silly I know but looking at how the prints are on the first layer its what it seems to be.

Ive got to figure out the corners to, on the tool holder your right in that its not important, but I want to print gears that will work together. Model pieces that join well. I don't see that happening if all the corners bow out :(

ok back to the learning curve.

Re: First prints questions

Posted: Sun May 01, 2016 2:56 am
by Jules
Slightly rounded teeth on the gears....do not let them come to a point. They will still mesh, and rounding a corner gives the machine time to turn in place - so less blob. (You can't do sharp points on gears anyway - makes them stick.)

When you start designing, you are going to have to leave a little space between your parts - like for pegs in holes. You can't make them the same size due to hole shrink. Ed recommended about 0.2 mm size difference when i started designing, and that's worked pretty well so far. (Square holes shrink less than round ones, and round pegs tend to shear off easily.)

Designing for these things is fun - but there's a heck of a lot to think about. :|