Consumer Design Projects
A small Wilmington, NC company named Porta-Nails, Inc. (PNI) found a successful niche in the consumer products industry by obtaining the rights to manufacture and sell a line of manual nailers and nails originally designed by Rockwell. These were intended specifically for installing hardwood flooring. While PNI also produced other niche products targeting woodworking and carpentry markets, the flooring nailer and nails were their flagship product. The tool underwent drastic change during the years I worked at PNI, from one style of nail and two types of nailers, to a line of purpose-built pneumatic and manual nailers and staplers as well as multiple nail lengths offered in two different styles; the traditional “T” Nail and the “L” Cleat. My responsibilities included leading many of the manufacturing and engineering changes to bring this about. A common phrase used at PNI was “we all wear many hats” and I was no exception to that. These are some of the projects with which I was involved.
The traditional manual nailer was initially designed for installing one type of hardwood flooring. Accessory pads or shims could be applied to the “shoe”, the portion of the nailer that rested on the flooring, to adjust for differing flooring geometries. The extension handle shown left was initially cast aluminum, but was changed to glass filled nylon and injection molded to provide lower cost and more durability. The change from cast aluminum to molded glass filled nylon reduced the instances of breakage from significant to negligible. A similar change was made in the “pusher” which changed from an aluminum extrusion to a glass filled nylon extrusion with much the same results.
The traditional “T” nailer was a basic staple of the rental industry for its reliability and was widely accepted for its simplicity and ease of use. Many of these tools returned their initial investment many times over in rental fees and nail sales.
The manual nailer saw many significant changes in addition to the extruded pusher. The “pusher” and the associated compression spring which fed clips of nails to the nailer were replaced by an extruded magazine with an injection molded pusher mechanism and constant force spring. This enhancement was taken from the design work on the pneumatic nailer design and adapted to the manual nailer in an effort to make the components more interchangeable, to drive down manufacturing and inventory costs, and to make the tool adaptable to different styles and sizes of nails.
The pneumatic flooring nailer was designed to emulate the appearance of the manual nailer. As demand for the product increased far faster than our design budget, we went to market on a limited basis in advance of cosmetic enhancements to the tool intended to more closely emulate its manual predecessor. However, market feedback after seeing the rough, sand cast look of the new pneumatic nailer favored retaining the appearance because it was viewed as more robust and better suited to industrial use. Acceptance of the tool was hindered by air volume and pressure requirements, which were slightly higher than competitive tools. Modifications were made and tests were run using the PNI pneumatic tool and several competitor’s tools. The results indicated that the traditional “T” Nail was the culprit in the higher air pressure requirements. The side benefit from the testing and modifications was that we now knew how to accommodate additional styles and lengths of fasteners with our tools.
The original “T” nail made by Porta-Nails was and probably still is the best fastener for holding down hardwood flooring. The cut nail pulls the flooring into position with the driving forces used to seat the nail and holds it there by virtue of its wedge shape. The tip of the nail is concave, presenting a cup face to the grain of the wood which inhibits splitting the wood and cuts the grain to allow penetration. This is also why the nail requires additional pressure to drive and to seat the nail. In pull out testing, the nail succumbed to elastic failure long before releasing its grip on the sub flooring. Except for one or two incidents, where nail manufacturing was contracted out to domestic sites while the Porta-Nails facilities were down, the “T” nails were manufactured from coils of rolled steel on high speed presses in Wilmington, NC. Addition of a laser welding system greatly improved the quality and consistency of the nail clips being produced over the previous method of gluing the nails into strips.
I've often speculated that the development of the “L” cleat may have resulted from patent protection granted the Rockwell “T” nail. The “L” cleat became the alternative method of attaching traditional ¾” hardwood flooring using tools other than the Porta-Nails tool. The traditional “L” cleat was a cut nail, but the serrations along the body were parallel instead of wedge shaped. The tip of the nail was rounded instead of cupped. This ultimately required less force to drive and seat the nail, although splitting along the grain could be an issue and the ultimate holding power was provided only by the head of the nail. As with the “T” nail, the shape of the cleat gives the fastener its name. Porta-Nails adopted the “L” cleat, and going one better, incorporated the cupped tip and the wedge shaped body while retaining a profile which would accommodate other tools that used the traditional “L” cleat. The “L” cleats were manufactured and imported, while the “T” nail was still produced by Porta-Nails, at their Wilmington, NC facility. Regardless of market preference for fastener type, we added the ability to fulfill that need.
During my tenure at Porta-Nails, we grew our offering from one style and length of fastener to multiple lengths and styles of fasteners available across several tools. This was accomplished through a combination of product design and private labeling of existing product to leverage competing methods in our favor. We were able to accomplish this in spite of shrinking markets caused by the growth in competition from big name companies with deep pockets and the advent of glue down and snap together flooring options which were much more attractive to the DIY market. I’m very proud of my contributions in both engineering design and as a member of the management team.
As part of the effort to continue broadening our offerings and to keep up with industry trends, PNI introduced an imported pneumatic stapler designed for installing the thinner laminate floorings coming to the market. Unlike long established standards for ¾” hardwood flooring, the profusion of styles and manufacturers of new, non-standard hardwood laminates, composite laminates, and bamboo flooring resulted in less than predictable flooring geometries and created issues with positioning the tool to deliver the fastener where it was needed. For this reason the “shoe”, the portion of the stapler that rests on the flooring, was designed to be adjustable.
Even with the added adjustments, some flooring geometries could not be addressed by simply adjusting the shoe.
Another refinement, shown in the second image, was the addition of a second trigger close to the air inlet to allow a more ergonomic hand position on the tool.
The Omni Jig dovetail jig was manufactured by Porta-Nails, Inc. from the mid nineties through roughly, 2008. Porter Cable made the decision to outsource the product to various offshore suppliers and following various quality and production issues was replaced by a new design. Many wood workers still own and swear by this design with it's precision machined cast aluminum frame and precision templates, and simple set up. This device is used in wood working to cut mating dovetail joints.
As a CAD professional, I've worked with and become familiar with a number of 3D printer makes and models and have even had the opportunity to work on a project related to the development of one such model of 3D printer.