3D Printing a Knuckle Duster Nozzle
Why print a new nozzle?
Somehow in the shuffle of activity in the shop recently, I lost the nozzle tip of my knuckle duster. It was a simple nozzle that screwed into the business end of the knuckle duster that was perfect for, well, dusting. The knuckle duster was effectively worthless without it.
I did a quick search and didn’t find where I could just buy the nozzle without a whole new knuckle duster kit. I wasn’t about to drop $10 to replace such a thing so I hopped on Thingiverse to see if there was one out there. To my surprise, there wasn’t. I found a Venturi style nozzle (that had the wrong thread, but I had an adapter) that was not nearly as good as I had hoped. So I fired up Fusion 360 and got my feet wet.
The Design
I am no means an expert at Autodesk Fusion 360 or even CAD for that matter. So it took me probably a little longer than it would most people. I first downloaded a pipe nipple model from McMaster Carr and modified it. That way I didn’t have to concern myself with the threads and I knew that would be correct (1/8″ NPT in this case). I then molded the non-threaded end of the pipe to be more like a nozzle.
The first design was simple, 1/4″ inner diameter, just like the original model. I printed it and then quickly went out to the garage to test it. Looking back, it shouldn’t have been a surprise that it worked as well as not having one on there since it was the same inner diameter as the knuckle duster. So I went back and filled in the center of it and closed down the diameter to 1/8″ and beveled both ends where it choked down to help with air flow.
This time I was justified in my excitement to try it out after a quick 25-minute print, it worked and worked very well. I want to say it probably works better than the original but there isn’t a good way for me to quantify that.
The Model
If you are looking to get your hands on it, I have it posted to Thingiverse where you can download it for free. If you want one and don’t have a 3D printer or access to one, contact me and I am sure I can print one out and mail to you fairly cheap.