Note to self: Don't buy 2lb spools of ABS again

Well I got an order of 3 new colors in today I normally buy 1lb spools but I wanted red and the place I buy from only had 2lb red in stock so I bought it.

Designed a large fume extractor hood that needs support (6-7 hour print) set it off and went to bed (next room, left door open) after a little over 2 hours I heard what sounded like belts slipping (tooth chatter) I ran out to find about 12 feet of red ABS filament wrapped around my entire machine. It came off the spool I believe due to it being so full and just tied everything up in a knot.

I just unspooled a bunch of it (until it quite springing off on it's own) and have to clean up the glass and start over.

Is there some method of keeping spools from unwinding like this?

gravity brake,


you essentially put piece of threaded rod through the centre with big cones and mount the spool on that, then instead of using bearings for it to ride on you simply use washers

I (and many others) use half a metre of ptfe tube to feed from the spool. In the attached picture you see two, one wrapped around the spool on the back, and another empty one from the bottom left and around to the top that I use to feed from the printed spool on the right.

I've had zero tangles with the big spool on the back using this method. The front one can tangle itself on rare occasions, but I usually catch it when I check in on the printer every couple hours or so.



Edited 1 time(s). Last edit at 11/09/2012 04:40AM by Nudel.

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-Nudel
Blog with RepRap Comic

I have been using this: Prusa-Top Spool Mount with tightly wound 1kg spools. No problems with premature unrolling.