Frank Xydias works in the Department of Engineering running Advanced Manufacturing and Computer Aided Design at Milford High School’s Applied Technology Center in Milford, NH. In this educational setting, the group often accepts “live jobs” acting like a job shop within the community. That was the case when they agreed to do a one-off part in a material they thought would be acrylic. The part was a pick-guard for a Danelectro Wild Thing Baritone electric guitar. But when the material came in they found out that it was in fact, PVC. Ultimately, this would be a milling PVC application.
Milling PVC Electric Guitar Pickguard
Application Technician, Kyle Newman, was assigned to the project and he was immediately confident that the job was a nice fit for DATRON technology. First, flat stock like this is ideally suited to the use of vacuum table workholding which is an option with DATRON machines. Secondly, a wide range of DATRON customers use their machines to mill and engrave engineered plastics including Delrin, Torlon, G10, FR4, Durastone, military-grade acrylic … you name it. So, milling PVC was not going to be an issue. As for the cuts required, there was nothing complex about the part – although Newman did have some concerns about potential delamination (due to the 3-ply construction of the supplied PVC stock) that might impact the edge finish.
CNC Programming and Tools for Milling PVC
The Mastercam file provided by the school didn’t include toolpaths or speeds. So, Newman brought it into Autodesk Inventor and used HSMWorks to create tool paths. A single tool change would be required with the contour cut being done with a standard DATRON 3mm single flute end mill and a smaller 1.5mm single flute would be used to make the mounting holes used to attach the pickguard to the guitar.
CNC Milling Machine Used for Milling PVC
Newman decided to use DATRON’s flagship M8Cube high-speed milling machine featuring a 60,000 RPM 2kW spindle and an integrated vacuum table. This machine also has an integrated probe which was used to map the surface of the PVC sheet to detect any irregularities. Irregularities were automatically compensated for in the software before the milling began.
Machining Strategies for Milling PVC Pickguard
Operation: Contour around profile of guitar, slot and larger through holes.
Tool p/n: 0068430E
Tool Type: 3mm dia. single flute
Width of Cut: 100% (3mm/0.11811″)
@ 25,000 RPM: 118.11 inch/min feed
Operation: Bore milling small mounting holes
Tool p/n: 0068015E
Tool Type: 1.5mm dia. single flute
Width of Cut: 100% (1.5mm/0.0590551″)
@ 25,000 RPM: 118.11 inch/min feed
Results of Milling PVC Pickguard
Regardless of the concerns about the construction of the supplied 3-ply PVC, the end result was perfect including the edge finish on the contour cuts and no delamination occurred. Newman was able to present the part to Frank Xydias who in turn, presented it to a very happy end customer.
