1 Topic by lawsy

  • lawsy
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Topic: Bridging performance

Hi guys,

After having my printer for a few days and spending a decent amount of time calibrating, my printer is working quite nicely. I did have a lot of trouble getting the first layer to stick, but this has now been fixed.

My main issue is poor bridging performance. This is the main difference in print quality I'm seeing compared to a Makerbot Replicator. I'm finding that even on short distances, the filament will not span gaps. It doesn't seem to catch nicely on either side of the bridge as it starts extruding. I've had to turn the solid surface layers up to 4 to compensate.

Does anyone have any advice on improving bridging performance?

A fan would help but isn't supported by the electronics. My other ideas involved playing with the 'extra length on restart' for retraction, or the 'bridge flow ratio' in Slic3r.

lawsy's Website

2 Reply by IanJohnson

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Re: Bridging performance

An earlier version of the Fan Duct I posted had a 40mm bridge across the top of the opening for the fan.  It would droop a little as it went across, and then tighten up straight as the plastic cooled and shrunk.

I have Bridge speed set to 80 in Slic3r and bridge flow to .7.  That helps to stretch the filament across.  I didn't have any trouble with anchoring on the ends.  It might help if there is a straight run into the bridge and not a direction change at the ends or in the middle.  You definately can't change direction in the middle of a bridge since there is nothing to stick to along the way.

3 Reply by lawsy

  • lawsy
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Re: Bridging performance

I'm going to run a series of tests to try and improve the performance.

If there is a 10mm gap, it will get about 2mm across before the string of hot filament breaks and curls. I'll post some photos as I complete my testing.

lawsy's Website

4 Reply by lawsy (edited by lawsy 2012-09-08 05:56:57)

  • lawsy
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Re: Bridging performance

I made a small piece to test on. Takes 1.5 seconds to slice and about 4min to print after heating.

All prints were set to 2 solid layers and two perimeters.

Print 1: 70mm bridge speed, 1 bridge flow ratio
Print 2: 70mm bridge speed, 1.2 bridge flow ratio
Print 3: 70mm bridge speed, 1.4 bridge flow ratio
Print 3: 70mm bridge speed, 1.6 bridge flow ratio

Edit: Didn't mean to hit post yet, will re-edit with pics.

lawsy's Website

5 Reply by FordGalaxie

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Re: Bridging performance

lawsy my brother what happened to the pictures?! haha

6 Reply by lawsy

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Re: Bridging performance

Turned out I had misunderstood what settings related to bridging in my early days. The entire exercise was useless as the test prints weren't relevant to what I was trying to achieve.

lawsy's Website

7 Reply by wire10ga

  • wire10ga
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Re: Bridging performance

Lawsy, nice to see you still around.  Thought you went over the dark side (CNC) on us smile

SD2 - Glass Bed, Fans on PCB and Y motor, Custom enclosure
Slicer - Simplify3D

wire10ga's Website