Hi all,
Wondering if anyone can help.
Ok, so first of all have been printing great with ABS. Updated to sailfish, still great. Sick of sprays and abs slurry and the like so installed a PEI bed. (Wanhao dup 4s)
Loaded a Red ABS which I’ve used before and now my prints are stringing with tiny holes. Can’t think how to fix or why it’s happening.
http://i.imgsafe.org/6d03db9.jpg
The top case was the original print, the case in the bottom of the photo is a recent print.
Now I used to print at 237c and 110 bed and these were perfect. Because of the PEI I use gcode temp override to lower the bed temp so I’m able to use the same gcode file as before.
Got 1 print off which was ok but not great quality, then extruder started to click when printing.
So I clean the nozzles out, and drive gears of the extruder motor and try again. No clicks, yey! But now the prints are stringing with tiny imperfections. I’ve noticed the ABS is leaking a lot, not like it used to.
Any ideas? Is it because my nozzle has been cleaned out and now over extruding/ extruder skipping?
Just wanting to know why this is happening now and how to fix. Sailfish is setup correctly reset to factory defaults so probably not a firmware problem.
Thanks for any tips guys
Usually when my extruder clicks I’ve got my bed too high and it can’t extrude properly. If you had glass before your new bed might warp when hot. I use lexan and have had problems with it deforming under the heat. I preheat the bed when I have to level it. Not sure if this is the problem, but it might help. Good luck!
Depending on how fast you’re moving 237 might be a bit hot as well. If you reset to factory it might have reduced your speed. 220 at 30mms is what I default to.
Based on what you described and the picture provided. I will says that it’s most likely your filament as absorbed humidity. This can happen when the filament is not stored properly depending on where you live there is a huge amount humidity in the air and ABS, PLA, Nylon and other filament absorb humidity quiet a bit.
You can put the roll in the oven at 50 degree C for about 3 to 4 hours (make sure the oven do not go higher than 50) I know it sound crazy but it’s a recommended practice.
I recommend you to store all your filament in sealable plastic bag and use more than the small desiccant little bag I use those small space dehumidifier and change them regularly I know it’s expensive but you don’t have much other choice.
http://www.amazon.co.uk/Pack-12-Dehumidifier-Discreet-Moisture-x/dp/B00CV79F60/ref=pd\_sim\_201\_5?ie=UTF8&refRID=0SANEM5R334KBT7Y7163&dpSrc=sims&dpST=\_AC\_UL160\_SR160%2C160\_
A pictorial that show the same issue:
http://reprap.org/wiki/Print\_Troubleshooting\_Pictorial\_Guide#Material\_Handling.2C\_Material\_Contamination\_01
Hope that help best of luck
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If it were me I’d clean out the extruder and then verify stepper motor operation (no missed steps) Then verify nozzle is clean with a flashlight.
Thanks for the tips guys.
Update: I’ve got rid of most of the stringing by printing at a lower temp (220) but that’s not the main problem now.
The prints are very weak, the case above where the vents are snap off while printing. When the print has finished its very easy and brittle to break. It was not like this before.
elmuchacho would humidity cause this weakness also? All my filament are kept in plastic bags then in a box, but I haven’t changed the desiccant in them from when bought a few months ago.
Nozzle and extruder are clean, what is the best way to verify missed steps?
When printing my abs at 237c I’ve always used a cooling fan to get better results. Wondering if this fan is now having an effect on the strength of the prints because I’m
Now printing at 220c.
I’ll put the abs in the oven, work out how to calibrate my extruder, re check and input filament diameter and try again at 220c 90c pei bed.
Perso I think 220 is too low and your part now are suffering from what could be referred as delamination.
http://reprap.org/wiki/Print\_Troubleshooting\_Pictorial\_Guide#Part\_Temperature
Who will make the part really weak and the effect accentuated if moisture has made his way through.
The problem with the small desiccant bag is that you never know when they are saturated with moisture and when they are ultimately they are useless. This is why I switch and use the small space dehumidifier who become gooey when saturated and you can ditch it in the bin.
I’ve printed literally 100’s of the hinges on the picture and even if made with PLA, I think the point is still relevant with ABS
Each batch of 20 hinges use 800gr of filaments and it’s rare that I open a new roll and always endup using the left over from the previous batch. If the filament roll is kept in sealable bag with dehumidifier for a period longer than 2 weeks part printed with the same settings are usually 10% to 20% weaker and I once forgot to store it and left the filament roll on the open air for 2 weeks while I left on holiday. Result was filament completely unusable for printing part requiring strength.
This is only my personal experience and the symptom you describe seems similar than I put my money on moisture it sound nuts that a little bit of water might cause so much problem but it really does.
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I agree with ABS @ 220C being too low - 230-235 is where I usually am when using hair spray or ABS Juice on a 110C bed.
To verify missed steps you can either remove the fan and heatsink from the extruder and look at it visually while printing a small test, or, unload the extruder and manually tell it to keep extruding using software such as Simplify3D and basically do the same.
Sometimes a quick spin on the stepper while it is unplugged will tell you if something is binding… Doesn’t sound like the issue at this point…
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Update 2: Ok so put the filament in the oven for 5 hours and managed to get an ok print finish @ 230c , success!
I store the filament for a couple of days and try another print. Disaster, similar to before. I’m thinking this can’t be right, so i try the print again but this time with new filament that’s never been opened.
Same problem awful quality and strings. I try this at different temps and still no joy. I’m thinking because I haven’t calibrated for this new filament so I’ll measure the diameter and try again at some point with a new gcode file. It started to print ok but as you see in the photos gets worse. When extruding this new filament when loading there were bumps in it, not nice and smooth as usual, thought this was strange.
Through out all of this I’ve noticed that any ABS I load, leaks out the nozzle more that it use to. I’ll load the filament, stop, and it will still come out slowly for a second or two, is that normal?
