Need help with bridging pleaseeee

Hello guys and girls!

I am having trouble bridging my prints, it seems that the filament isn't actually touching the layer below it to make the bridge between gaps.
I attached a drawing to show what I mean (viewed from birds eye view, from the top).

When I print a hallow cube, viewed from the top, the left side wall, right side wall and front side wall of the cube make contact with the top layer bridging filament, but the back side wall of the cube, isn't touching it causing the bridge to just fall down because it isn't supported.

Could anyone help me resolve this issue? I tried to play with settings, but I don't think its a settings issue... atleast not bridging settings, maybe my perimeters/width arn't set up properly?

I am using 1.75mm filament with 0.4mm nozzle.
ABS with heatedbed + kapton tape.


Any advice would be helpful!
Thankssssss

1) What type of machine?
2) What slicer and version?
3) What are your speed settings in the slicer?

Fl0yd

Edited 1 time(s). Last edit at 05/31/2013 05:01PM by Fl0yd.

Yeah, couple things that could cause that.

Without knowing more, I would increase your extrusion multiplier. Maybe up to 1.05-1.07.

You should be printing support and bridges much slower than perimeters and infill.

I'd recommend 30-40mm/s for support and 15mm/s for bridges

If you supply more info, we can narrow it down for you

Also perhaps increase # of perimeters, and change bridge flow rate ration to 1.1-1.4 bridge fills go down thicker because there is usually no material beneath them.

are you running a fan with your prints? that will make a big difference for bridging your prints. Getting the correct cfm flow will make a difference as well. also set your controller to slow down the speed during bridging if you have the ability to do so.

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Hello Floyd!

1) What type of machine?
I am using prusa mendel

2) What slicer and version?
I am using slic3r version 0.9.8

3) What are your speed settings in the slicer?
All my speed settings are at 15mm/s for now until everything is calibrated


What you think I can try to do??

Hey cope413.

My speeds are all at 15mm/s for now,

I will try to experiment with my extrusion multiplier when ever I get to put my hands on my machine and I will post the results! Thank you cope413!

Speed settings in Slic3r are important, but also speed settings in your firmware.

Btw, I sometimes have the same problem that it looks as if the hotend doesn't attach the filament to the wall, but otherwise my prints print out perfectly, and usually at the second layer it does adhere enough to bridge correctly.

Hello reprap squad! I do have a fan, it is attached parallel to the hot end, I attached photo, what you think? Set up properly or I should change something??

Thanks for your input!

Hello Cope, I finally managed to try out the extrusion multiplier, but it didnt seem to work lol...

I attached copy of the hallow box opened up and viewed from the inside to show what I mean, would you have maybe another tip I can try?

Hello james!

I tried to change number of perimeters and flow ratio, but it doesnt make any dif at all unfortunately..

Also want to point out that I swapped the 0.4mm nozzle with the 0.5mm nozzle.



I am having exactly the same problem as ohmarius. the hot ends nozzle just isnt going far enough to adhere to the perimeter and make the bridge...
What can I try next? I dont even know where to begin... any advice would be helpfull...

Hey ohmarius,

I am having the same issue you are, but mine is much more severe lol. It doesnt fix itself in second layer...

My bridges are completely unexistant...


What did you do to improve your print quality?

there is another thing to try. slightly reduce nozzle size in slic3r. this will allow the walls to be calculated closer together. it seems like the flow is still not correct. have you slowed down the bridging feed rate?


also what is the surface area of the bottom of the nozzle,or at least the diameter? it looks rather large. if this is the case, then you probably need to print with larger layer heights. try printing at 0.3mm layer height. bridging may not be working properly because the end of the nozzle is clipping the filament from the inner wall of the object being printed. thicker layers on z axis may stop the issue, as long as flow rate is correct.

read a post somewhere that a users hot end was loose and this caused some serious slop that prevented proper prints. make sure also that this is not your case as well.

Edited 1 time(s). Last edit at 06/03/2013 11:37AM by jamesdanielv.