[Replicator] Beginning of Print Mishaps

[ulysses]

Hi,

I just got my Replicator today, and it's awesome, but when I first
start printing an object the extruder lets out a long line of filament
as it gets into position to begin the print. Is this normal? I've
been using a raft to minimize the effect this has on the print, but it
still makes the print a bit uneven. Anyone have any ideas of how to
fix this?

Thanks

[Luis E. Rodriguez]

I'm guessing this is the test extrusion but I would refer to the documentation (http://www.makerbot.com/docs/replicator/) or contact sup...@makerbot.com.

 

Let's see videos or pics!

 

Luis E. Rodriguez

Are you a Maker?

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[Greg Thorstad]

Have you tried turning on Outline and then the line of filament should lead
to the outline and then not be in the printing area.

Greg Thorstad, B. Comm.
Thorstad Computer/Thor3d.ca/Canadian Makerbot Distributor
Box 268
Outlook, SK
S0L 2N0
306 867-9596

[whoaimin3d]

I've looked through their documentation, but wasn't able to find
anything. probably because people are just now getting their
replicators. Here's some pictures showing the problem I'm having:

The starting thread: http://i.imgur.com/uiJuQ.jpg

It starts off the platform and moves towards the center of the build:
http://i.imgur.com/gJ30w.jpg

I'll contact makerbot support if no one has encountered this problem
before

Thanks

On Mar 8, 11:26 pm, "Luis E. Rodriguez" <lrodriguezm...@gmail.com>
wrote:

> I'm guessing this is the test extrusion but I would refer to the
> documentation (http://www.makerbot.com/docs/replicator/) or contact

> supp...@makerbot.com.

>
> Let's see videos or pics!
>
> Luis E. Rodriguez

> Are you a Maker? <http://www.makerfairekc.com/>

[Rob Giseburt]

Looking at the start.gcode for the Replicator you see that it’s mostly intentional:

G0 X105 Y-70 (Position Nozzle)

G0 Z0.6     (Position Height)

M108 R4.0   (Set Extruder Speed)

M101        (Start Extruder)

G4 P1500    (Create Anchor)

That sets the position, which I’m guessing is off of the right side of the platform, then starts the extruder running at 4RPM, and pauses for 1.5 seconds. Then it starts the print, without shutting the extruder back off.

This is slightly odd, and definitely something that could be changed. For example, to stop the motor and then give you 1.5 more seconds to clean it, add these two lines to the end of ReplicatorG/machines/replicator/Single_Head_start.gcode or Dual_Head_start.gcode :

M103        (Stop Extruder)

G4 P1500    (Wait for cleanup)

That last line is probably pointless, since it will most often simply wipe the noodle off on the side of the platform anyway.

Also of interest is that the Dualstrusion_start.gcode uses 5D commands, moving the E axis directly, and does not leave the extruder running into the print.

  -Rob

—

MakerBot Operator

Member of CCCKC Hackerspace

Member of KC Fabricators Google Group

[whoaimin3d]

Great find, that explains it. I won't be able to play around with the
settings until next week as I'll be out of town, but I'll let you all
know how it goes then.

[Gerald Orban]

You could also take advantage of the new M codes for the Replicator and pause the toolhead until a button is pressed using:

 M71 (Remove the excess plastic and press button to continue.) 

:)

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[W. Craig Trader]

FYI, in SkeinForge 47, the Outline plugin is now called Skirt.

- Craig -

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[Michael Wren]

Identical issues with my Replicator, I'm trying out a raftless print
with a "Skirt" added to the default profile now. Once the platform
warms up, that is.

[Michael Wren]

On second thought, I have several other things going wrong that need
tweaking before I play with raftless.

My earlier first out-of-the-box print turned out fairly good though.

http://i.imgur.com/sQexO.jpg
http://i.imgur.com/pPzAX.jpg

[whoaimin3d]

Looks pretty good. One other thing I noticed with my Replicator is
that the top of a print looks really solid and sealed off and
"finished", while the bottom of a print will look messy and
incomplete. Have you had this issue? Anyone know how to avoid this?

On Mar 9, 3:09 am, Michael Wren <phr...@mac.com> wrote:
> On second thought, I have several other things going wrong that need
> tweaking before I play with raftless.
>
> My earlier first out-of-the-box print turned out fairly good though.
>

> http://i.imgur.com/sQexO.jpghttp://i.imgur.com/pPzAX.jpg

[Jamesarm97]

My TOM does that also, I think to get the plastic going. I find it is so thin the head just melts right over it and it does not get in the way. Mine is a very thin line like a hair.

[Greg Thorstad]

I have no Replicator experience( you are one of the few who does) but if the
bottom is messy it might be that you are not starting close enough to the
platform. You might need to increase your z offset.

Greg Thorstad, B. Comm.
Thorstad Computer/Thor3d.ca/Canadian Makerbot Distributor
Box 268
Outlook, SK
S0L 2N0
306 867-9596

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[Mark Cohen]

Perhaps you have support turned on and thats the material that needs
to be pulled off.

[Owen M Collins]

Are you printing on a raft? or w/o a raft?

O.

[Michael Wren]

Here's the bottom of that same shark (this was printed on a raft), it
turned out fairly messy:

http://i.imgur.com/Er8lE.jpg

Seems like some of the first layer didn't really want to stick
properly.

I moved the platform a bit closer to the extruder with the leveling
screws and printed the 20mm test cube rafted and the bottom looked a
bit better. I followed MakerBot's leveling procedure, but it feels
like the center of my build platform is actually lower than the edges
by some amount.

Bottom: http://i.imgur.com/qOyc1.jpg
Top: http://i.imgur.com/dizLV.jpg

One thing I'm noticing is that the bottom few layers are inset
slightly, resulting in a rounded or keystoned edge at the bottom. You
can kinda see that in the calibration cube.
Also, my raft doesn't seem very "smooshed down" yet, so it might be
the z offset that Greg mentioned.

[whoaimin3d]

I have the same leveling problem as you. When I run the leveling
script I can make it a pretty tight fit, but when it does the last
check in the center it's always a fairly wide gap compared to what I
aimed for in the previous steps. Also, when it calibrates the front
left corner, the left extruder (I have dual extruders) will end up
hanging off the side of the build platform by about a millimeter or
so. I asked MakerBot about this and they said they have heard simila
reports and are working on a ReplicatorG fix for it. Did you also
encounter this problem?
I guess try loosening all four pegs a bit and seeing how that goes.

People with Thing O Matics, how does the bottom of your prints come
out? Messy or solid and flush?
I have only printed with a raft so far, by the way. I don't have any
pictures of the bottoms of my prints and won't be home for about a
week so I won't be able to take some more pictures or test anything
out until then.

[Gary Crowell]

When I get mine (still 2-3 weeks away) I intend to clamp a machinists dial indicator to the head and run it across the platform; reads in fractions of a mil, and much more objective than a slip of paper.  Besides leveling, it will clearly determine if the platform is flat.   Of course, 'leveling' isn't the proper term either.  You're not leveling it, you're making it parallel to the travel of the heads.  The proper term is 'tramming'.  FWIW

Gary

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[whoaimin3d]

Good idea, I'll see about doing that with mine as well. What do you
think the ideal height is between the nozzle and the build platform?

I'm also worried that the build platform isn't perfectly flat. It may
be bending upwards at the ends as, like I said, after I calibrated the
center of the board was much lower than it should have been

> Linkedin <http://www.linkedin.com/in/garyacrowellsr>
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[Aljosa]

With regards to the test extrusion this is to replace the outline. The extuder goes to the corner of the build plate extrudes an anchor and then continues an extrusion to the beginning of your print.

What print head have you selected for printing with is this all set to default stuff that is in RepG 33?

Also can you do me a favor and go to machine>motherboard on board preferences inside of RepG, and tell me what your X and Y offsets are set too?

On Thursday, March 8, 2012 10:15:47 PM UTC-5, whoaimin3d wrote:

[Cliff L. Biffle]

On Fri, Mar 9, 2012 at 9:04 AM, Michael Wren <phr...@mac.com> wrote:

Here's the bottom of that same shark (this was printed on a raft), it
turned out fairly messy:

Out of curiosity, does your bot engage Z-hold unexpectedly while printing the first layer?  I recently fixed a bug in RepG that caused the same behavior on my bot: it was generating small Z moves that caused lost Z steps and drifting.

-Cliff L. Biffle

[Coley]

I have the same problem with my Replicator.

I just checked the build platform against a steel ruler and it is warped.

It's about 05.mm out, very disappointing!

> > makerbot+unsubscribe@googlegroups.com.

[whoaimin3d]

Well that really sucks, I suspect many people are going to have a
warped board then if the 3 of us are all having this problem. Have
you contacted makerbot yet?

> > > > makerbot+u...@googlegroups.com.

[Far McKon]

I saw a lot of activity, and just wanted to check in on this thread for a second. I'm going to hit the key points.

Build Plates: We noticed these are not level too, and we have (literally) daily updates on the solution.  I'm collecting some info from production about this, and I'll try to get it out as soon as I understand it.  My plate on a bot here seemed a bit out of level (0.3mm maybe?) and I myself did some tinkering with the *order of tightening down the level screws* and after :15 got it to be closer.  Maybe that is another way to get a bad plate closer to level (or is that trammeled?). If it works for you as well, let me know, and we may make it an official fix.   We are on meeting daily about this (literally), and are scrambling to up the accuracy on those plates as fast as we can.  I'll make sure more info on this is posted as I get updates.

Print Anchor:  That is indeed an anchor! Ahoy!  We shipped the old style anchors in start.gcode for 0033, we will ship updated anchor code in start.gcode in 0034.  It's good to see folks tinkering with their anchor code, what we picked was a good baseline.   I'm already picking up tips from this list on what to do better baseline in future releases. Your custom fixes and individual itch-scratching are a great reference as we update things, so as you find start.gcode options that work best for you,  keep posting 'em, I love to read 'em.

Bottom Layer on raft problems: We have seen some of this in-office, but nothing that has set off alarm bells.  Since you folks are noticing it, we will take another look into it.

Thanks again for keeping an eye on our quality. This kind of feedback (and being Open Source) means we can find problems faster, make releases smarter, and in general keep in touch with the reality of what our bots produce in garages, craft-rooms and classrooms. Thanks for being on this group, and for part of that great feedback loop.

hack on,
- Far McKon

Nerd Herder (aka Software Dept. Director)
MakerBot Industries

[whoaimin3d]

While it's great to see that you guys are really on the ball with
this, what will happen if the build platforms are actually physically
deformed? It seems that they are warped upwards, with the edges of
the platform permanently closer to the extruders than the center of
the platform is.

[Gerald Orban]

I have a feeling that they've delayed further shipments of the Replicator in order to (hopefully) resolve or better this issue. I spoke to their customer support yesterday asking why I didn't receive an update and shipping window last week. They said that they're working on sending an update out with a new shipping window, no timetable for that though.

[Gary Crowell]

On Mon, Mar 12, 2012 at 12:10 PM, Far McKon <farm...@gmail.com> wrote:

I saw a lot of activity, and just wanted to check in on this thread for a second. I'm going to hit the key points.

Build Plates: We noticed these are not level too, and we have (literally) daily updates on the solution.  I'm collecting some info from production about this, and I'll try to get it out as soon as I understand it.  My plate on a bot here seemed a bit out of level (0.3mm maybe?) and I myself did some tinkering with the *order of tightening down the level screws* and after :15 got it to be closer.  Maybe that is another way to get a bad plate closer to level (or is that trammeled?). If it works for you as well, let me know, and we may make it an official fix.   We are on meeting daily about this (literally), and are scrambling to up the accuracy on those plates as fast as we can.  I'll make sure more info on this is posted as I get updates.

I like trammeled, but the correct term is trammed.  The only reason I nitpick about this is that: 1) I strongly believe in using the correct terminology where appropriate, and educating when necessary, and B) I absolutely guarantee you are going to get someone with problems who swears they "leveled" their platform... and later you'll find out they used a bubble level (if that hasn't happened already...).

Gary

 

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[SpeedBump]

Mine is warped the other direction with the center higher than the
sides.

[JohnA.]

How thick is the metal on these new build platforms?  (Anyone with a replicator and a micrometer?)


JohnA.

[Coley]

Yes, I did contact Makerbot support and they said that it is a recognised fault.

They will be sending out a replacement aluminium plate once they have some.

> > > > makerbot+unsubscribe@googlegroups.com.

[Paul Breed(unrocket)]

Hard to measure exactly as its backed by the heater PCB...
Best guess is between 3.5 and 4mm.

[Nick Tuttle]

Yup.. me too.. by about 1 mm.. Thought it might of happened during shipping since the example piece included looked much better than what I have be able to do.. 

Also It seems the thumbscrews might loosen due to the springs being too short??

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[whoaimin3d]

So I noticed today that as a print progresses, the nozzle becomes
closer to the layer it is printing. I think this is why the bottom of
the prints are so poor in quality while the top looks smooth. Maybe I
can add a Z-offset or something in the beginning of the print? How
would I do that?

[Gerald Orban]

Hey guys,

Just want to resurrect this thread as I've run come to a point where almost all prints from the right head of my Replicator Dualstruder aren't extruding correctly. Here's a shot of the screwless cube gears center piece. I attempted to print 3 today: the first one the left completely failed about halfway through (barely any plastic was being extruded) and the second failed at about 75%.

After these two prints I decided to take a look at the extruder head and gearhead. I took apart the extruder and noticed that there was a misalignment from the filament inlet to the entry of the hot end of the extruder. I also noticed that one of the fan wires had fallen down and become pinched between the screw holding the plate ontop of the motors to the hot end and forced the stepper out of alignment. I moved the wire back into a place where it wouldn't bind and pinch, reseated the stepper and screwed the whole assembly back together. I then printed my third attempt at the center hub (and a set of pins) shown below.

As you can see the problem seems to have lessened but I'm still getting wildly unreliable extrusion from the right extruder. My left extruder however, has worked flawlessly from the beginning.

I've tried a few other things which haven't seemed to help the extrusion process:

• Increase extrusion temp to 230C
• Reduce print speed (20mm feed, 27mm travel)
• Different skeinforge settings (0.2mm-0.3mm layer height, 0-2 extra shells and 0-50% infill and combinations of most of those)

Nothing seems to do the trick and I'm hoping someone out here can offer some advice, thanks!

[Rob Giseburt]

Considering all you have said so far, I'd have to guess that the thermocouple is placed badly. Do the temperatures shown on the screen seem stable, and close to the set temp? 

  -Rob

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[Aljosa]

Gerald two things to check here. 

First thing I would check is your filament diameter in Print-O-Matic (or if you are just using SF with POM turned off check in there). Make sure that is set to 1.82 iv seen these settings get messed up sometimes which can cause issues.

The other thing to check will be your filament plunger. I have seen similar things to what you are experiencing when there is too many washers in there. To do this take all the steps you have already done so that you remove the stepper from the extruder carriage. Once you have the stepper in your hand unscrew the two bolts that hold the filament block to the stepper. Then slowly take the front half off and under there you will see a little plunger and some washers around it. If you see that there are 3 metal washers inside there you are going to want to remove one, and reassemble the entire thing and give that a try. Also check what Rob said and make sure the thermocouples are secure.

What the likely cause of your problem is that there is too much tension on the filament, which is causing what your seeing week bonding of layers, and skipping at reversal points. Also bring your temp back down to 220C and then try again.

[andrewupandabout]

I had a similar thing. The first test print I had didn't go smoothly because the platform is either not hot enough or calibrated right.

Here is my first video. Any suggestions are appreciated. I plan on making videos to slowly show how I corrected the issue.

http://www.youtube.com/watch?v=ZBbJ7ZkrRFE&feature=context&context=G28cb4beFAAAAAAAAAAA 

Andrew

On Thursday, March 8, 2012 11:26:41 PM UTC-5, Luis E. Rodriguez wrote:

I'm guessing this is the test extrusion but I would refer to the documentation (http://www.makerbot.com/docs/replicator/) or contact sup...@makerbot.com.

 

Let's see videos or pics!

 

Luis E. Rodriguez

Are you a Maker?

On Thu, Mar 8, 2012 at 9:15 PM, ulysses <koen...@gmail.com> wrote:

Hi,

I just got my Replicator today, and it's awesome, but when I first
start printing an object the extruder lets out a long line of filament
as it gets into position to begin the print.  Is this normal?  I've
been using a raft to minimize the effect this has on the print, but it
still makes the print a bit uneven.  Anyone have any ideas of how to
fix this?

Thanks

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[Gerald Orban]

Rob and Aljosa, thank you for your help!

I checked the thermocouples of both of the hot ends and they are both secured tightly. I ran a print using the right toolhead (which printed mostly OK) and noticed that the temperature never deviated more than 2 degrees from its setpoint. I think we can safely say that the thermocouples are not the source of the problem.

So I went ahead and looked at the stepper motors like Aljosa had suggested and found some very interesting debris (see below).

 versus the left toolhead which looked like 

As you can see the right filament is leaving the stepper motor's gear and entering the hot end far away from its intended position: you can see gouges in the side of the filament. This also explains the chugging/crunching noises that the stepper motor is making as it attempts to force the filament into the hot end. The left stepper motor is properly aligned.

I then took apart the plastic casing infront of the stepper motor to see how many washers were holding the plunger in place (see below):

Just to ensure consistency I opened up the left stepper motor (see below):

There are indeed two washers (two metal and two plastic). It seems like there may be one too many metal washers but I'm leaving it up to your judgement.

After I verified all of this, I reassembled the cartridge ensuring that everything lined up and the result was the same.

HELP!?

[Mark Cohen]

Mk7s use 3 metal washers so I assume mk8s should be the same.

Sent from my iPhone

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[Gerald Orban]

If that were true, then wouldn't I see the same problem in both extruders? The left one extrudes fine.

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[Rob Giseburt]

You would really need to measure the washers (together) with a caliper to know if they are the same. It really is that delicate/precision.

I can think of two other things:

• Make sure the drive gear is aligned with the filament. See "Attach drive gear to motor" at http://www.makerbot.com/docs/thingomatic/mk7/ and this image in particular: http://www.makerbot.com/docs/thingomatic/mk7/attachment/415/

The alignment there is vital.

• I had this problem: Make sure the filament isn't bound up. I determined that it had somehow formed a knot (the end must have slipped under one loop while I was putting it on) an it wouldn't feed any more. 

  -Rob

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[Gerald Orban]

I have a pair of calipers to measure with however, they're not digital.

Having my filament binding at the spool was one of the first things I checked out and for each of my prints while diagnosing it (and when using the right extruder period) I manually spin the spool a bit to give it a bunch of slack every 10-15 minutes during a print. There's definitely no knots or binding of any kind happening outside of the extruder, I have even loaded and unloaded multiple times: the filament slides in and out of the whole assembly easily.

I'm running a print using the left extruder right now and will check out the links you provided once everything's cooled down.

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[Aljosa]

First of 2 metal and 2 rubber washers is the correct stack-up. MK8 is not the same as MK7 as the rubber washers have changed a bit so your good on that end.

Since we ruled out the first few things I would check what Rob suggested and see that the drive gear is indeed lined up correctly with the channel the filament has to pass through. The other thing to make sure is that the drive gear is indeed securely attached to the motor shaft, and that that set screw isn't loose.

Can you do me a favor and clean up the right head, heat it up and manually push filament down into the system. Tell me if you feel an abnormal amount of friction when compared to doing the same on the left extruder. 

Once you do that can you also take a picture of both extruders like you did you in your original post but where there is no debris so I can see a bit more clearly how the filament is traveling.

[makerman]

You can temporarily interchange the  motor connections. I the right extruder is still the problem one then it will rule out problems with the stepper driver.

If you interchange stepper motors, this will rule out problems with the motors.

Then there are only  mechanical problems to look at.

[Gerald Orban]

Checking to see if the drive gear was securely fastened was also one of the first things I'd checked before posting on here :) It's definitely as secure as it can get without fear of stripping the screwhead (or breaking the allen key).

I heated up the extruders and pushed filament through them. I started with the right and it felt like I had to place way too much force on the filament to push it through and actually bent the filament from applying too much force. On attempting to pull out the filament it snapped off inside the hot end somewhere leaving a piece of it inside the head. When I attempted the same with the left extruder it was surprisingly easy to push filament through and was able to pull out the filament without issue.

Seems like we've narrowed down the culprit!

Here are some photos of the entry into the hot end of both extruders:

And the left:

There's nothing visually distinct on the outside between either of the extruders. I also took some photos of the bottom of the carriage just in case. The left extruder has a big of nuclear green hanging off of it (the OK one) and the right is the adjacent head.

So what's next.. Do I have to disassemble the hot end? :( I'm not liking the sound of that...

[Gerald Orban]

D'oh, posted two of the same photo. Here's the right extruder's thermocouple hookup.

[Gerald Orban]

I did that a few days ago and even swapped the washers and plastic plates to no avail :( Same result.