MMDR Designs 3D Prints a Working Pocket Knife on Form 1 3D Printer

I am always fascinated by the new designs and creations that individuals and companies come up with. Whether it is a 3D printed Lego man, a 3D printed driveable vehicle, or a 3D printed gun, it seems as though each and every week there is something that fascinates me just a bit more than before.

One company, MMDR Designs, pride themselves on “turning ideas into reality.” The company, consisting of David Rosenfeld and his wife, had mostly been taking on 3D printing projects for their co-workers, friends, and family, until recently when they decided to take the next step and form an official company.

Rosenfeld, who had a hobby of creating knives using conventional means, has recently taking a liking to the processes of 3D design and 3D printing, and using some of his old designs decided to try and come up with a 3D printed pocket knife.

“The knife design was created a long time ago using the old fashioned method of pen, paper and trial and error,” Rosenfeld tells 3DPrint.com. “Back then, I made knives out of steel and aluminum by hand using a drill press, grinder and a scroll saw. I heat-treated the components, assembled the knives, showed them to some friends and put them away in storage and forgot about them for about 10 years.”

Rosenfeld then purchased a software package created for designing objects for CNC machining, called BobCAD. Using it, he attempted to turn his original knife drawings into a CAD file and then try and fabricate it on a CNC mill. After teaching himself how to draw in BobCAD and how to use a CNC mill, Rosenfeld found that some of the components of his knife were not coming out how he had intended in the CAD software, thus he put the project aside.

“A few years later, I bought Alibre (now Geomagic Design) and started teaching myself that program,” Rosenfeld told us. “During the Alibre learning process, the world of 3D printing was starting to come into its own at a semi-affordable, home-use level. My Alibre knowledge increased significantly, but my desire to continue to machine steel and other metals began to decrease. I became increasingly frustrated with the results from my own lack of machining skills.”

So, Rosenfeld decided to try to enter the 3D printing world by purchasing a MakerBot Cupcake 3D printer. After using the Cupcake for some time, it was eventually retired, and he ended up purchasing a 3D Systems Invision LD. The Invision LD allowed Rosenfeld to experiment more with what 3D printing technology was capable of, and it brought his attention to potentially 3D printing a knife. Around this same time, Rosenfeld discovered a new 3D printer by Formlabs, called the Form 1.

“I started the process of finishing the drawings for the individual knife components,” said Rosenfeld. “It was around that time that we purchased the Form 1 (3D printer). With many successes and many failures from our Form 1, I considered trying to print the knife parts out on it. When Formlabs released their version of Preform that enabled the users to better calibrate the XY scaling, I decided to print this knife. Most of the parts were oriented with the supports on the spine to preserve the front and back surfaces.”

As for the knife, the resin allows for the blade to be sharpened like more traditional metal knives, although Rosenfeld believes that the resin is probably too brittle for the knife’s liner lock to continue functioning, day in and day out. At the same time though, he never modified his drawings from his original design for the metal knife.

“I did not draw the liner lock with the bend in it because when machining it, the liner lock would be cut from a flat piece of stock, heated, and the locking mechanism would be bent and then cooled to retain the shape,” said Rosenfeld. “So, I never updated the drawings for better printability. I plan to update the drawing and attempt to print it again, however, we no longer have the Form 1, so we will either have to use the Invision LD, send it to a printing service, or acquire another 3D printer.”

Regardless, 3D printing appears to be on the course of creating knives printed in strong plastic materials that could potentially become useful tools. At the same time though, this could also bring up potenially controversial issues such as 3D printed weaponry. Plastic knives, if created with strong enough material, could lead to security issues on airline flights and at certain events where metal detectors would not be able to detect them on passengers and attendees.

What do you think? Will we one day soon be able to 3D print plastic knives that could actually be useful tools and weapons? What do you think about this design by MMDR Designs? Discuss in the 3D Printed Pocket Knife forum thread on 3DPB.com.