Nov 30, 2016 | By Andre

Considering the incredible number of independently operating components present in just about every modern piece of technology, it's easy to forget that most of these features were added one step at a time. Take your smart phone for example: in it you will find GPS, gyroscopes, WiFi adapters, cameras, speakers, and all manner of useful bits of technology that ultimately jive together so you too can catch that elusive Pokemon. In the world of affordable 3D printing, however, the feature list of what is available is still in its early stages of growth. So while heated platforms and dual-extruders are features that have been around for a while, additions like auto-levelling are only just becoming standard in newer generation machines.

A Kickstarter campaign is now under way for Sentinel, an innovative filament detector and cleaner module—just the sort of tool that will likely become a common feature in the world of desktop 3D printing in the very near future. Because of this, jumping on board with the trend now might be your best chance to get ahead of the game, and for a very low price too. 

The compact device—barely larger than your standard AA battery—is an optical sensor-based 3D printer add-on, tasked to perform two very important functions. As many of you know, the filament that gets pulled through into a 3D printer's extruder needs to be devoid of any debris that might clog the tiny hot-end nozzle (often a hole 0.4mm or smaller in diameter). The Sentinel's first feature is a foam pad that wipes away much of the potential debris from the extruding filament's exterior before it has a chance to get sucked into the plastic ooze chamber that is the hot-end.

The Sentinel's second feature is an optical sensor that can detect when a spool of filament is about to expire and subsequently pause the 3D print in progress. For anybody that has come back to check on a 24 hour 3D print only to realize the machine has been printing air due to an empty spool, this little contraption is the perfect solution.

The below promo video suggests that “more often than not” the team behind the Sentinel find themselves with an incomplete print due to filament that has run out. And while that is certainly an exaggeration (a typical 1kg spool of filament does go a long way after all), there is nothing more frustrating than losing a print due to material reasons.

The device works using similar optical sensors often found within a 3D printer's end-stops. These are tools that help zero the x-y-z axes and help position the extruder in place before any print starts. Basically, if the optical sensor built into the Sentinel detects a gap where you should expect filament as the extruder motor pulls along, it will send a signal to the printer that something is wrong and pause the print.

This detection feature, plus the combination of a custom circuit board and communication with your printer’s on-board software, enables the Sentinel to operate as it does. Unfortunately (or fortunately, depending on how you see things) it relies heavily on open source protocols for compatibility, so it is unlikely to work with your Makerbot or Ultimaker. This said, the Sentinel team are hoping some of the larger print manufacturers get on board as time goes on.

Whether or not this nifty little addition to the 3D printer's arsenal is worth your investment is entirely up to you, but for $35 (early-bird price) you won’t have to break the bank to have that extra bit of added security for your long 3D prints.

For me, as someone that runs filament through 3D printers consistently on a daily basis, having auto filament detection is certainly an important tool to have. And yes, while there are prosumer grade 3D printers already available that have optical filament sensors in place, having a modular option like the Sentinel for units that don’t is a great thing to have.

Of course, just like any Kickstarter campaign, there are risks and challenges such as maintaining production schedules, quality control, and ultimately funding in the first place. But considering DYZE Design, the team behind the campaign, has been in the 3D printer racket for quite some time now, I readily trust their ability to deliver on their word.

So while its likely that every next-generation, filament-based 3D printer will be equipped with the features being promoted in this Kickstarter, having a low-price option today is certainly a bonus.



Posted in 3D Printing Technology



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Dyze Design wrote at 11/30/2016 7:00:00 PM:

Wow! Thanks Andre for this amazing article!

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