Extrution build up problem

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3DFrost
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Extrution build up problem

Post by 3DFrost »

Hi, so I've almost got my H1-1 almost printing well (almost) but my prints keep being messed
up. For some reason in certain parts of the print the print head will just stop for a half second
causing excess extrusion to build up at that point, messing up any layers that might be printed
around or behind it.

So I'm wondering if this is problem with either Slic3r or Mach3 and how I'd go about fixing it?

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mhackney
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Re: Extrution build up problem

Post by mhackney »

Hey 3DFrost, what type of a PC are you running mach on and what is your kernal speed. When does the pause happen - always at the same spot if you print the object a second time or in a different time? Does it happen in 1 direction like X only or Y only?

A couple of things to check starting with the simple:

1) check the tensions of your belts and also that the idler pulleys (especially the X ones) are not binding and turn freely. I had a situation where one of these was not rotating and I would get a pause and hop of the print head.

2) have you run the Mach test app (I forget what its called) to make sure your kernal speed and PC are up to snuff? Hesitations that are random might be due to this.

3) Does this happen with more than one printed thing? If it happens on everything you print it is probably not a slicing issue but may be one of the above.

Start with something simple to print like a basic 1" cube. Work on that until you solve the problem and then fine tune and move on!

cheers,
Michael

Sublime Layers - my blog on Musings and Experiments in 3D Printing Technology and Art

Start Here:
A Strategy for Successful (and Great) Prints

Strategies for Resolving Print Artifacts

The Eclectic Angler

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3DFrost
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Re: Extrution build up problem

Post by 3DFrost »

mhackney wrote:Hey 3DFrost, what type of a PC are you running mach on and what is your kernal speed. When does the pause happen - always at the same spot if you print the object a second time or in a different time? Does it happen in 1 direction like X only or Y only?

A couple of things to check starting with the simple:

1) check the tensions of your belts and also that the idler pulleys (especially the X ones) are not binding and turn freely. I had a situation where one of these was not rotating and I would get a pause and hop of the print head.

2) have you run the Mach test app (I forget what its called) to make sure your kernal speed and PC are up to snuff? Hesitations that are random might be due to this.

3) Does this happen with more than one printed thing? If it happens on everything you print it is probably not a slicing issue but may be one of the above.

Start with something simple to print like a basic 1" cube. Work on that until you solve the problem and then fine tune and move on!

cheers,
Michael


Hey thanks for the response

So I don't think the tension on the X axis is too high if anything it's a little lose
I'll have to look into a Mach 3 test app but the hesitations are not random (in a particular print)
It's really rather a strange problem, currently I'm working with that 5mm steps calibration and where (looks like the thing from qburt)
it will stop varies due to settings I think but where it stops will always be the same in a given print.
By this I mean that in one print the head stopped moving on every layer (even though the perimeter of the next steps is smaller)
in the middle of the steps relative to the x axis.

Now on another print in which primarily the rate of extrusion was changed the print head no longer stopped in the middle but at the far
end of all the steps again stopping in the exact same place per each layer.

Idk that might be hard to understand I could upload photos.

It seems to happen with most of my prints the head stopping in different places depending on the print :/

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mhackney
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Re: Extrution build up problem

Post by mhackney »

Too loose tension can also lead to skipping teeth but then you get a "leaning" print. A photo of a print might help if you can post one.

Stoopid (sic) question but did you move the X carraige by hand (with no power to the stepper) to see if there is a "catch"? Same with the Y table?

Regards,
Michael

Sublime Layers - my blog on Musings and Experiments in 3D Printing Technology and Art

Start Here:
A Strategy for Successful (and Great) Prints

Strategies for Resolving Print Artifacts

The Eclectic Angler

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3DFrost
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Re: Extrution build up problem

Post by 3DFrost »

mhackney wrote:Too loose tension can also lead to skipping teeth but then you get a "leaning" print. A photo of a print might help if you can post one.

Stoopid (sic) question but did you move the X carraige by hand (with no power to the stepper) to see if there is a "catch"? Same with the Y table?

Regards,
Michael


Ya well I'll have to post pictures I don't think it's a binding issue because now that I think about it it stops
moving on either the x or y axis or both (has stopped in a particular spot on circular prints as well)

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mhackney
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Re: Extrution build up problem

Post by mhackney »

It might also help to post your gcode file. If there is something in there from slicing, it should show up. Does this happen in the first few layers?

I still suspect your PC and/or Mach config. Some PCs are notorious for not working well with Mach. Do you have CNC experience with Mach or is this your first time? What type of PC and OS are you running?

cheers,
Michael

Sublime Layers - my blog on Musings and Experiments in 3D Printing Technology and Art

Start Here:
A Strategy for Successful (and Great) Prints

Strategies for Resolving Print Artifacts

The Eclectic Angler

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