cant get bridges right

Printer: Solidoodle 3 (RepRap Based)
Slicer: Slic3r 1.0.0RC1
Control: Repetier Host
Filament: 1.75mm ABS
Temps: 200/105
Enclosure: Yes
Nozzle: .4mm

I can't get bridges to go good! Using Slic3r default speed of 60mm/s for bridging, the strands don't anchor (or snap or something and curl up) which screw up the print. Faster speeds only make it worse. Slow speeds below 20mm/s for bridging, the strands anchor and go correctly, but sag a little bit. I tried lower bridge flow ratio in Slic3r and it doesn't help the sagging and only makes the fill on top of the bridges more sparse. Tried higher bridge flow ratio and fills better but makes it sag more.

help!

You might need to try a higher nozzle temperature so that the strands don't snap.

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4MULE8
You might need to try a higher nozzle temperature so that the strands don't snap.

Tried that, no go. Don't want to go much higher than 240c for fear of damaging my extruder

I've grizzled about bridging in Slic3r before. I drew a simple bridging model to find out why Slic3r struggles sometimes (see pic). What happened was, after the supports were printed to bridge level, the first part of the bridging started by laying the perimeters down (3 perimeters chosen in Slic3r), BUT, the perimeters were extruded from the extreme ends of the supports so the filament was laid in a continuous 'stretching' mode from one end to the other - the bridged portion was straight without sagging. Once the perimeters were done, Slic3r then started the bridging proper from the INSIDE edges of the supports - the result wass sagging filament or the filament did not even attach to the supports. I wish Allesandro would look at this this!

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Waitaki 3D Printer

Quote
waitaki
I've grizzled about bridging in Slic3r before. I drew a simple bridging model to find out why Slic3r struggles sometimes (see pic). What happened was, after the supports were printed to bridge level, the first part of the bridging started by laying the perimeters down (3 perimeters chosen in Slic3r), BUT, the perimeters were extruded from the extreme ends of the supports so the filament was laid in a continuous 'stretching' mode from one end to the other - the bridged portion was straight without sagging. Once the perimeters were done, Slic3r then started the bridging proper from the INSIDE edges of the supports - the result wass sagging filament or the filament did not even attach to the supports. I wish Allesandro would look at this this!

Wow, that sounds exactly like the problem I'm having. I'm getting the sag in the middle of the bridge like you said, not the perimeters of the bridge. Seems like this would be an easy fix for the slic3r team to do. How do we get the slic3r guys to fix it? Let's all mass email them.

Well, the author on here goes by the name of "Sound" although I'm sure he's reachable at Slic3r.org.

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Waitaki 3D Printer