Welcome! Log In Create A New Profile


Filament feed rate?

Posted by 2SH43 
Filament feed rate?
June 26, 2013 11:09AM
Whenever I start a print, the filament doesn't extrude within the first 3 seconds of the print. The filament comes out quite slowly and only touches the bed around the 4th second of the print, causing the filament to curl up and not really stick.

Is this because of the feed rate? Or is it due to other problems that I'm oblivious about? I'm very new to 3D printing, so much more to learn. As for now, I'm pretty much stumped.

I'm using a Printrbot Jr with Pronterface + Slic3r
Re: Filament feed rate?
June 26, 2013 12:55PM
Do you do anything to make sure your hot end is primed. At least you should extrude into the air until you get good flow, nip off the filament with tweezers and then hit the print button (or some similar procedure).

You can also do the same thing with a g code preamble that slic3r allows you to add. I have a preamble that homes, moves to the right, sets the z height to 0.5mm, extrudes 3 millimeters of filament, pauses for 2 seconds, moves QUICKLY back to home, and then moves onto the print. The idea behind the quick move is to basically "wipe" the print head before the print starts. The idea behind the 0.5 height is that as the head oozes during warm up, there wont be an excessive amount of filament building up.
Re: Filament feed rate?
June 26, 2013 01:59PM
Yep. I extrude a lil filament before any printing. Some extra plastic would even ooze out.

As for g-code preambling... I got lost after "preamble" xD. Maybe I'm not looking close enough, but I can't find a "preamble" setting.

Here are some attachments of my settings.
open | download - 1.jpg (147.4 KB)
open | download - 2.jpg (104.1 KB)
open | download - 3.jpg (146.5 KB)
Re: Filament feed rate?
June 27, 2013 12:26AM
In the printer page, there is a tab for custom gcode, and one of those is for starting gcode. You have to type in the g code you want to be added to the beginning of the generated g code.
Re: Filament feed rate?
June 27, 2013 02:39AM
I'll have to do more research about this. Pretty much clueless as of now.

Thank you for the useful tips! I'll be sure to put it into use! grinning smiley
Re: Filament feed rate?
June 27, 2013 03:10AM
Have a look at this while your at it...


Waitaki 3D Printer
Re: Filament feed rate?
June 27, 2013 11:26AM
I am not at my printer right now, so I'm only going by memory, but here is an annotated list of my start g code:

G28 # home
G90 # make sure were absolute
G21 # make sure were metric
G1 X50 Z0.5 F1800 # move out on the X axis and park 1/2 mm from the print surface
M140 S[bed temperature] # turn on the bed heater
M104 S[ext temperature] # turn on the hot end heater
M190 S[bed temperature] # wait for the bed to reach operating temperature
M109 S[ext temperature] # wait for the hot end to reach operating temperature
G92 E0 # reset the E axis
G1 E5 F1000 # extrude 5 mm of filament
G4 S3 # wait for 3 seconds
G92 E0 # reset the E axis
M117 Proceeding # display on the LCD
G1 X0 F4000 # move quickly back to the origin to "wipe" the hot end
Re: Filament feed rate?
June 27, 2013 12:06PM
Oh wow thank you for those!! In the notepad it goes!!
Re: Filament feed rate?
June 27, 2013 11:09PM
Just a caveat - I'm not sure at all of the syntax for the temperatures. Of course you could use literal numeric values, but it's better to use slicer variables. I think the square brackets is the correct syntax, I'm just not sure of the variable names.
Re: Filament feed rate?
July 02, 2013 01:33AM
And the hashmark (number sign) might not be the right character to disclude the comments from the gcode. Mine always uses a semicolon. Just my 2 cents.
Re: Filament feed rate?
July 02, 2013 10:06AM
You may be right about the comment delimiter. Like I said, I was (and still am) away from my printer and just going from memory.
Sorry, only registered users may post in this forum.

Click here to login