AnsweredAssumed Answered

Pre-Drill diameter vs Finished diameter in wood

Question asked by Kara Tucker on Jul 3, 2019
Latest reply on Aug 2, 2019 by Kara Tucker

Hi everyone, 


I work with hardwood and plywood components. Our company is transitioning to using SolidWorks, and we are also creating a hardware standard. Most of our components will be CNC'd, but there are some that require pine, poplar, or maple. 


One of the components I am transitioning now has a 1" pine body. There is a top piece that must be removable for maintenance. We've been using 2 1/4" trim head wood screws to attach this piece to the body (it really doesn't need much maintenance once it's installed). We have never visually shown the screws in the 3D model, and now that seems to be imperative for proper communication. 


Something I can't figure out is: 

Do I need to be designing the holes for the trim head screws as pilot holes or at their finished diameter? The problem is, the carpenter's have told me that they don't need to drill a c-sunk hole, but when the screw is inserted, the head does compress the wood away. 


Should I represent these holes as simply sketch points on the wood surface and give the carpenters the option to pre-drill if needed? I did see that the pilot hole would be about 3/32" for this application. 


Thank you!