Need advise on bridge failure

I get pretty good prints on everything but bridges so I decided to do some testing. No matter what settings I use in Slic3r (speed, bridge speed, temp....) I end up with about the same results.

[youtu.be]

If I print smaller things that have bridges they fail but not as bad as this bridge only test. Most items with no bridges seam to print pretty good.

I don't know anything about the software on the board other than it's Repetier. I use a Buda schnozzle (SP) and Gen 6 board. The machine is an Airwolf printer.

I normally print ABS at 240c and the default for bridge speed was 80 though I tried down to 40. Nozzle is a .35mm

In the video the bridge speed was 40 and temp was 230.

Any ideas?

Looks too cold and extruder too slow. I only print with PLA so ABS might be different but that is oozing out the extruder way too slow and is not hot enough to come out thin enough to span the gap. Check your filament dimension and double check the temperature of the hot end with a IR thermometer.
If you post the STL you are using I'll video my machine doing it if it helps any.

Edited 1 time(s). Last edit at 02/02/2013 04:36AM by Wired1.

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Richmond, New Zealand
Thingiverse ~ YouTube

my guess in this case:

extruder has too much back pressure slow down bridge speed by half and possibly lower flow rate for the entire print. also temp does seem a little low, what temp are you running at?

>>>In the video the bridge speed was 40 and temp was 230.

>>>I normally print ABS at 240c and the default for bridge speed was 80 though I tried down to 40. Nozzle is a .35mm

How accurate is that temperature? might be a loose or inaccurate thermistor.

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Richmond, New Zealand
Thingiverse ~ YouTube

Been fighting with my bridge issue some more to isolate the problem and I noticed something. No matter what I set the bridge speed to (Slic3r 7.2b) the perimeters of the bridge print with the perimeter speed.

I tested this theory by setting the perimeter speed to 125 (set 3 perimeters) and the bridge speed to 8 and sure enough, it went back and fourth 6 times (3 perimeters) at full speed before dropping to a crawl.

I know I have other issues but this makes it harder to narrow down the culprit.