Woodfill impressions, oozing issue.

I noticed that as well smells like freshly cut wood which I love

to get rid of oozing in between prints I use a bit of code in my start up the moves the axis up about 15mm does a real extrude of material of about 20-30mm and as it is doing this extrude I place my tweezers so each arm is on one side of the nozzle tip. When the extrusion stops the regular printing begins so the printer starts to move to do the skirt and at that moment I pinch the tweezers closed and actually allow it to scrape across the nozzle tip cleaning it. The print continues with a fialment that is just primed for printing so result are much more accurate no waiting for filament to flow normally. This process will eliminate the oozing that occurs between prints as well.

It is very successful for me I have been using it ever since I started playing with gcode

the code I use is placed at the end of the existing startup code and looks like this:

G1 Z0.00 F5000; move to z endstop
G1 Z15.0 F5000 ; raise nozzle 15mm
G92 E0 ; zero extruded length
G1 F200 E25 ; extrude 25mm
G92 E0 ; zero extruded length again

as I said I add this so it is the last bit of code right before the print itself starts

 

The only things I know of that can affect bridges are:
Bridge printing speed -- I would think faster is better
Filament temp -- I would think cooler is better
and bridge flow ratio; a param in Repetier I set mine at .9 , or 90%of normal

 

Hi Tyler,

Please tag me on posts like this so I don't miss them.

Woodfill can be a tricky beast. My suggestions would be to turn down the temp. 190 should be good. You'll also need to dial in retraction. Probably a little faster retraction speed, but it may not be that much of an issue when you reduce temp. One more thing to consider might be a faster non-print move.

I can't tell from the pic, but make sure you're printing at pretty thick layers. 0.2 should be about the thinnest you go with a 0.4mm nozzle. You can go thinner with a larger diameter nozzle.

There are some tips here: http://learn.colorfabb.com/how-to-print-with-woodfill/
Follow the makerbot replicator 2 tips. That is much closer to the robo than the Ultimaker is although both are quite different.

 

The tagging is brand new.

Yes, the barnacules video is a little old. Colorfabb has learned more since then. I actually routinely print it a heck of a lot faster than they recommend, but the temp settings are more important to get right for this than any other material.

When I say increase speed, I mean for non-print moves. Stick with their guidance for print speed until you get it nailed down a little.

Woodfill definitely has its challenges, but once you get it nailed down, I think you will find it to be one of your favorite materials. It's definitely one of mine!

 

It looks like you need to go cooler still or to get a little more agressive with your cooling, although I have to say that bridging and overhangs are usually one of the really strong points of woodfill so I'm a little surprised.

What hot end are you running with? A 0.4mm is the min you can run with, but you really need to be careful with settings. If the material sits for too long in the nozzle or is too hot then it clogs really easily. This becomes much less of an issue with larger nozzle diameters. I use a 0.8mm on my ultimaker and can print at 100 micron reliably.

For cleanout, you should be OK following the standard cleaning processes. Get a piece of guitar string, push it up through the nozzle end while it's hot, then flush it through with some good clean PLA.

You generally want to avoid having the wood sit in the nozzle when possible. Purge with PLA after prints. Don't let the nozzle sit warm for more than a few seconds before starting your prints.

 

What diameter nozzle is on the E3D?
(I think the default was 0.4 but I know I ordered some larger and smaller)

Good information @Printed Solid -- I'll bump mine to at least the 0.6 when using that.

 

I have a lot of nozzles in stock if you want to give a larger diameter nozzle a try.
You definitely can print this stuff with a 0.4mm nozzle and many do, but you've really got to get settings dialed in perfectly.
I have 0.4mm and 0.6mm V5 nozzles and V6 nozzles (which are compatible with the V5) all the way up to 0.8mm.

I really should write a blog post about big nozzles. There are some huge advantages as long as you don't mind the loss in x-y resolution. Faster build times and stronger prints. It's also really hard to clog a nozzle that big so it's super easy for beginners to use.

In the future, I plan on also including a few sticks of nozzle cleanout filament with every order, but I haven't been able to get any in stock yet.

 

When I say I should do a writeup on larger nozzles, I actually mean, 'it's on the list of things I'd like to do, but will never find the time to actually do.'

 

Damnit! I'm going to go knock something off the list. Bowden tube stuffed with short lengths of different types of filament, here I come!