Homemade 3D Carving Duplicator

[Frank] is a guitar builder and has to make a quantity of acoustic guitar bridges that wouldn’t make sense to do manually by hand each time. He wanted a way of duplicating bridges quickly and precisely but he didn’t want to go to a CNC machine. Instead, he build a 3D duplicating machine.

The machine has 3 perpendicular axes, just like a milling machine. Mounted to the Z Axis is an air powered spindle that can reach 40,000 RPM. All 3 axes are moved by the operators hands. Normally, free-hand cutting something like this would be very difficult. [Frank’s] solved this in his machine by using a stylus that is offset from the cutting bit. The stylus is the same effective length and diameter of the cutting bit and is guided over a finished bridge pattern. While the stylus is tracing the pattern, the spindle and bit are removing material from a bridge blank. The stylus is continually moved over the entire pattern bridge until the spindle is finished carving out a new bridge out of the blank.

To aid in lifting the heavy Z Axis and spindle, [Frank] added a counter balance to make tracing the pattern extremely easy. Once the new bridge is carved, it only requires minor sanding to remove the tool marks before being installed on a guitar! [Frank] admits his linear bearings and rails are very rigid but also very expensive. If you’re interested in a less-expensive 3D duplicator, check out this project.

Copying complex objects in wood

[Matthias], eminent woodworker he is, designed and built an awesome machine to make copies of just about any object imaginable. With a few scrap 2x4s, and a few bolts, screws, and skateboard bearings, you too can copy anything into a solid block of wood.

The theory of operations for [Matthias]’ copy carver is mounting a router and ‘follower’ to the same piece of wood. Put that on an XY table with a rotation axis, and just about any object can be copied in wood or plastic. It’s not too dissimilar to a Dulplicarver, a routing machine meant to copy everything from gun stocks to guitar and violin bodies.

So far, [Matthias] has copied a rotary phone and a sadly non-functional wrench.  It’s the perfect follow-up for [Matthias]’ 3 axis pantograph router that can copy and enlarge any random flat object you can throw at it.

via Make