|Nick Clarke 3||07/03/2021 10:28:50|
1159 forum posts
Fitted a new reel of Filament to the 3D printer (Ender 3) and it was quite springy. The feed to the head was a bit jerky but I didn't notice until a duff print was produced.
I realised the spool was not keeping in step with the needs of the printer but sometimes over ran allowing the filament to go slack - not only between the reel and the head but on the reel itself.
I think I have fixed the original problem with a couple of elastic bands (thoughtfully left on the drive by the postman) wound round the tube it sits on providing a minimal amount of friction and preventing the over running but due to having been loosened the filament now jams in the loose winding on the reel when the feed reaches the cheeks of the spool.
What to do? Carefully unwind the filament until a tightly wound section is reached and dumping the excess, the same but try to carefully rewind it tightly or saying 'to hell with this its only £20' and dumping the whole reel to obtain reliable printing?
5834 forum posts
Do lyou expect the filament to be tight between the spool and the feeder? I always stand by the machine pulling it off to avoid this and leaving a suitable amount loose. Means I can't leave it for more than a coupe of minutes though. Rather than adding friction I keep meanig to make a ball bearing spool holder.
|Nick Clarke 3||07/03/2021 10:54:23|
1159 forum posts
I didn't seem to be the looseness that caused the problem but rather the top layer in the spool becoming loose and then trapping the outgoing filament so it jerked before carrying on.
|Dave Halford||07/03/2021 11:36:36|
|1395 forum posts|
I would have thought that any filament 'spring' would always cause the outer layer to uncoil the first chance it gets given a bit of slack. You might have success with making a soft foam 'grommet' to fit between reel and drive to run the the filament through.
That said it's a shame to waste a whole reel and Creality talks about a tight filament pathway, which you don't seem to have so perhaps the spool is not to spec.
943 forum posts
Don't ditch it, the reel can probably be saved. Firstly rewind the reel to get rid of serious overlaps and more importantly make sure the filament is not trying to tie itself in a 'clove hitch' where the end has managed to get under one or more previous turns. Then make sure the filament is dry, put it in a bag with some fresh silica-gel for a couple of days. Also worth checking that the entry and exit points to the bowden tube are nice and smooth, no sharp corners. Restrict the reel from swinging too much, as you have with the elastic bands.
It helps to buy quality filament have a look at the following images the first is from Prusa (Prusament) note the even wind. The second is an unknown brand but note how uneven the wind is. The difference is fairly obvious as is the outcome. Always try to keep the filament under control when loading. Even a smoothly wound roll can end up in a mess if the turns become too loose.
The second image also shows some useful ball-bearing spool holders (search TUSH on Thingiverse). I have recently made myself a dry filament feeder box using these ** Journeyman's Workshop ** and they work well.
Edited By Journeyman on 07/03/2021 13:02:57
|Alan Wood 4||07/03/2021 20:30:12|
|190 forum posts|
I would echo the comment that despite being a new reel the filament might have a high moisture content and needs drying out. I always soak heat a new reel before using. 36 to 38 degrees for PLA/ABS /PETG for 5 hours.
1775 forum posts
I have this problem - I have a stick leaning against the spool, in contact with the filament to act as a restricter, works perfect
|Neil Wyatt||07/03/2021 22:52:31|
18558 forum posts
It's amazing how filament bvaries in its vulnerability to humidity. I recently had a reel of PLA where the unwound length filament would spontaneously snap after about 24 hours. Because of the move another PLA reel spent weeks with an unused section when moving the printer I had to cut it because I couldn't get it to snap, even bent double!
Clearly there is PLA, PLA and PLA!
|Henry Brown||08/03/2021 13:02:44|
438 forum posts
I've had similar issues with PLA, even though the printer is in the living room and apparently the more exotic filament can be worse! I have some silk silver PLA that seems to be very susceptible to moisture and some Aldi black PLA that has gone brittle as its got towards the centre of the roll.
I started off by putting them in the oven for a few hours at 50 degrees C but found that the enemy wanted to use it for cooking so invested in a cheap second hand food dehydrator that has a timer and temperature control that seems to do the trick just as well. There are several blogs/videos on the web showing how to do this.
5834 forum posts
Those spool holders immediately made me think of rolling roads. Got the ruler out and yes, my spool is gauge 3.
Is brittleness the sign of damp? I hear people mention it and thought the problem was the danger of steam generation during melting.
943 forum posts
|Henry Brown||08/03/2021 18:55:02|
438 forum posts
This is what moisture does, the little pits are just about visible:
It can be heard popping while printing and if it happens on the outer layer is quite visible and it is supposed to weaken the print if excessive. This is the silver silk PLA I mentioned in my earlier post, after drying I have almost removed the moisture and it has printed quite well this afternoon.
I made a spool holder from some 50 x 50 box with some POM wheels that the spool mounts on, I mounted it on a large block of oak as the spool has to be parallel to my printer due to space limitations.
Edited By Henry Brown on 08/03/2021 18:57:27
|not done it yet||08/03/2021 19:25:37|
|5790 forum posts|
Nylon is the worst for a steam problem - it can absorb loads of moisture.. PLA will be brittle and break easily if it picks up moisture.
Please login to post a reply.
Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!
You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.
Click THIS LINK for full contact details.
For subscription issues please see THIS LINK.