Musings and Experiments on the Art and Science of 3D Printing

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Friend's don't let friends use oil...

By Michael Hackney Friday, June 2, 2017

Back in the dark ages when humans knew not the subtleties of FFF 3D printing, many tried elixirs, potions, broths, salves, incantations, and many other unscientific and unproven so-called remedies.

It was a dark and dangerous time – especially for those unknowing and unenlightened followers. The "oil myth" started in the early days (circa 2013) of the full metal hot end; that which we know and love today called E3D (taking a bit of liberty here, historically, the oil treatment was developed by a Replicator 2 user as best I can tell. But the word spread fast to the delta community who were grappling with those long, filament-strangling Bowdens). The early E3D was a slightly different beast than the then-current J-head state-of-the-art hot end. And many unwittingly assumed the E3D and other all-metal hot ends of its ilk would work exactly the same, but only better. They did not understand the subtleties of a short melt transition zone that is the hallmark of these all metal designs.

So they continued to blindly slice with long and rapid retracts. And lo, as they printed, the filament – most notoriously, PLA – would jam. "It can't be my beloved slicer or filament or my lack of understanding so it must be this cursed hot end" proclaimed many. "We must lubricate it into submission. If it wants to jam, then let's oil the darned thing." And oil they did - Canola, peanut, corn and many other oils were used. And "good results" were exclaimed by those silly enough to go down this path. Until, that is, until other, more challenging problems arose – first-layer adhesion problems, inter-layer adhesion problems, gummed up extruder drive gears and a general unkempt appearance on and about the 3D printer.

Meanwhile, a few brave and hardy soles were determined to study and understand the problem. They invested 1000s of hours collectively (and some of us individually) to hypothesize and test – you know, the scientific method that seeks truth above all else. And lo, these pioneers discovered that retracting molten filament past the short melt zone and into the heat exchanger is bad, very bad. And more importantly, does not fail catastrophically 100% of the time so the unwitting could not correlate the results to its cause with certainty. However, those brave and determined few DID correlate the results to the cause. They dissected hot ends and nozzles and heat breaks by slicing them latterly after quenching in liquid nitrogen. They invented the "cold pull" test (blush) to study the shape of the melt zone and nozzle geometry, and they came up with theories, testable theories, to determine once and for all what was really going on.

Meanwhile on the forums and groups, the oil-mongers propagated their myth at a time when many, many new 3D printer users were entering the field. Not knowing the hows or whys, these noobs saw the exuberant claims made by the oil-mongers and fell prey to them. Creating a new cycle of perplexed and frustrated users.

It was just at that time when the results of all the hard and scientific work were made known after much collaboration and cross-checking and verification. The cry went out "No oil, no oil good people! It is not necessary and actually creates more problems than it solves." Data and results and explanations were shared. And the nascent hot end manufacture took note and rather than get defensive they embraced, welcomed, understood and appreciated the work and dedication to truth and understanding. They tested and verified the results on their own and went the extra steps to make changes, changes that would later propel them to the top of the hot end market for performance, reliability(!) , functionality, innovation and design aesthetics. They realized the minor flaws in their earlier designs that might lead users down the slippery oil-covered path and fixed them, saving countless others from the "oil myth" of 2013-2014.

You can read about this here: E3Dv6 Release Announcement & Design Details. And the all-important quote that tickled and caused this author to blush slightly:

• Fix niggling reliability issues.

v5 has a great track record of reliability with less than a fraction of one percent of users experiencing issues due to manufacturing issues, however we really wanted to eliminate any chance of future defects.

1.75mm Bowden users were experiencing a disproportionate amount of problems, which was traced back (with much help and hard work from Michael Hackney) to nozzle geometry in certain situations needing high extrusion pressures that resulted in starvation of filament flow.

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The first reference I can find to the use of oil for preventing PLA jams was posted on the MakerBot Operators Google Group on 1/14/13. I have not found an earlier reference, if you do please let me know!


3 comments to ''Friend's don't let friends use oil..."

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  1. You should be proud of all your contributions to the 3d printing world. Sit back and think of all the people that you have effected in a positive way. I know this article was not about you but I read that E3d link and they go out of the way to give you credit for your detective work and your accurate fixes. Btw the above article is very informative, as I have friends that swear by the oil phenomenon. I will direct them to read this. .....it is very funny as well. Good job

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  2. Thanks Jim. My goal is to do good work and share my knowledge. I may not always be right but at least I'll have the data to defend my position. Sometimes I'm missing data (as happened recently with a comment I made about the E3D sock [which I love]) or occasionally I misinterpret my data. This is all "normal science". Everyone can't be right all of the time and when I discover I made an error I do correct it as I did regarding the sock situation. If you are interested, here is the post and my comment is at that bottom: http://www.prusamk2.com/how-to-have-success-with-the-e3d-silicone-boot/?fb_comment_id=fbc_1350862241601845_1508865439134857_1508865439134857

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  3. There was some good discussion to this post on my Google+ page. I don't know why comments there aren't shared here and vice versa: https://plus.google.com/u/0/115992239115727196001/posts/67j5eD1NbbS

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