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This is an automated visco (safety) fuse spinning machine. I built this myself in the spring of 2011 at Franklin W. Olin College of Engineering as a passionate pursuit. I designed and built a visco fuse (safety fuse for fireworks) spinning machine. It takes 20 spools of thread and wraps them around a black powder core, and then coats the 1/8" fuse in a waterproof nitrocellulose lacquer. It operates at a speed comparable to commercial machines (the plates spin at 544 rpm, making fuse at 204 in/min) and is built for safety; it is entirely non-sparking and removed from ignition sources. I designed it completely from scratch and machined all of the parts in the Olin machine shop.

In order to replicate it exactly, you will need a 2-axis CNC mill, a manual lathe, and a band saw. Some parts have 'High Performance' and 'Easy Machining' configurations; the High Performance parts require the use of a CNC mill, however the Easy Machining parts can be made using a manual mill. Thus the 'Easy Machining' configuration can be made entirely without CNC. Use the eDrawing file of 01-00 to view the 'Easy Machining' configuration if you don't have SolidWorks. Both designs use rubber O-ring belts as power transmission, and the 'High Performance' model uses a pair of gears, which should be greased with thick grease. Fasteners are not included in the model, 1/4" Economy T-nuts (MSC P/N 93888972) are needed to mount some parts to the frame, otherwise determine fasteners by hole size

Some parts of this are off the shelf, and not necessarily easy to find an exact match. The Sunbeam gearbox can be found fairly easily online, however, I can't remember which surplus site I bought the motor for, and even if I did they probably don't have it anymore. Therefore, you must find a motor on your own, and a few of the parts that connect to the motor you will have to size to fit your motor. Make sure you get at least 1/6th of a horsepower continuous duty at ~1700 rpm out of your motor. The less open to the air your motor is, the better, as it will be easier to shield it from black powder dust, which CANNOT get into your motor, otherwise you risk explosion.

Check it out on Hack-A-Day for a summary of what you've just read!


Machine Running
Feature on Olin Project Archive
Burn Tests


All CAD are SolidWorks files. See Links for SolidWorks viewing software. The two profile files are needed only to modify the frame extrusion profile. 01-00 is the top level assembly. A .zip file of all the CAD is available to save you clicking. It does not include the profile files.
01-00 eAssembly
80/20 1010 profile
Simplified 1010 profile

Technical Drawings

This is a full set of technical drawings. Some parts have to scale .dxf's that correspond to them, allowing you to upload them to a CNC machine to cut these parts. A .zip file of the whole package is available to save you clicking.