Best Filament Suppliers

If you think Woodfill is steep, buy some BronzeFill
(carbon fiber is not exactly 'cheap' either)

@Printed Solid has very competitive pricing for US customers and great service/support.

 

My take on where we are at with filament manufacturers right now in mid 2015:

In early 2013, my experience working with even higher end standard quality filament was that the quality was occasionally junk. The cheap stuff at the time was nearly complete and total garbage. A few of the issues I encountered: air bubbles, entrapped moisture, large contaminants (my favorite was chunks of wood that actually clogged the heat break), large diameter fluctuations, splices in the spool, filament glued to the edge of the spool (spools were solvent welded together and the filament stuck), filament being too brittle from being wrapped too tight, and feeding issues from retained spool diameter from the spool being too small. It's also worth pointing out that some of the best printing spools came from suppliers who had major issues with other spools.

Fast forward to today: The cheap stuff has gotten better for sure. Suppliers have learned from experience extruding tons of ABS and PLA specifically for 3D printing. You should still expect a higher rate of issues with those commodity materials. Maybe expect a bad spool rate of 10% or less vs the 40-50% I was seeing (varying by supplier of course, ESun is definitely one of the best Chinese suppliers, I know first hand that there are some that are much much worse). Aside from that percentage, you should see pretty good The higher quality North American and European manufacturers should keep you well below 1% and have more consistency within that 1%, but you're paying for it. It always boils down to time vs money. If you have the patience to lose the occasional print, then the cheap stuff should be fine for many prints. Even within cheap Chinese brands, you may have differences by reseller branding since different resellers have contractual quality requirements and may or may not perform inspection of the spools as they receive them. So, the Esun filament you get from toybuilder labs under their prototype supply label is not necessarily the same as the Esun filament you pick up from some random ebay seller. My advice here is to avoid the cheap material (including the stuff that comes with the printer sadly) until you get things figured out. There are just too many variable already to have to deal with potentially bad filament when you don't yet have the experience to be able to tell whether you are having a filament problem, printer problem, slicer problem, etc... After that, it is up to your needs. Personally, I use higher quality material for any functional jobs or prints that I am being paid for, but do occasionally buy cheap stuff for trinkets.

The above holds true for ABS and PLA where the cheap Chinese suppliers have developed their manufacturing processes on the backs of their customers. It doesn't hold for anything new (or at least not until it's not new anymore) and especially doesn't hold for filled materials. As you've learned from running your own printer, different polymers behave differently in extrusion. Some amount of development work is necessary to develop a process that can produce quality filament at production volumes. This is true just when switching to a new material. When you add in the complication of filler, the amount of development work goes up; you're intentionally adding what should be very tightly controlled contamination into the mix. This is part of the reason why, for example, when you back a kickstarter from protopasta for their new conductive filament, there is some amount of time that is required between when the campaign closes and when they can actually ship material. The cheap Chinese suppliers? Not so much development time is given to new materials and the important quality characteristics are not at all established. They let the market figure it out for them. I can tell you first hand that within days of release of bronzefill, I received sales calls from several Chinese suppliers saying that they had metal filament ready for me to purchase. They used pictures from other manufacturers in their marketing literature. One even showed pics from shapeways! Obviously at that point, they hadn't even made any of that material.