Maritime Wood

Consider this: Two power tools both, for the sake of comparison, drills displayed side by side at the corner hardware store. At first glance they seem to be the same, but the-price-tag signals difference. One drill might run as low as $25; the other over $100. The store clerk explains that the expensive drill is a “professional” model, hence the higher price. Is this a marketing gimmick, or are there true differences between the so-called professional tool and the nonprofessional, or “consumer” type?

Simply put, professional tools are designed to be more powerful, last longer, and perform better under stress than their consumer counterparts. They are built for carpenters, boat builders, electricians anyone who uses a power tool day in and day out to make a living. They are designed to stand up to heavy-duty, knuckle-busting use. Consumer tools -for home handymen- on the other hand, can perform the tasks assigned to them usually as well as the professional type, but they aren’t built to last under ‘round-the- clock abuse. The differences between the two types of power tools are strictly of function and designs, which are ultimately reflected in the cost to manufacture them and the price to the buyer.

For example, the motor in a professional power tool has to be able to handle an extremely heavy work load, so it must generate more power than a consumer tool. It also must withstand as well as sustain overloading for long periods of time without burning up.

Of primary importance are the ratio of power to weight and the physical dimensions of the motor. A professional uses his tool all day long, so the lighter and smaller it is, the more comfortable it will be to use. He wants the maximum power from the minimum package, so whatever weight and bulk can be eliminated makes the tool more easily handled. The proper designing of a professional tool is complex.

The selection of wire for winding the motor of a tool is important. The choices are aluminum or copper wire, with the latter usually used in professional tools and the former found in consumer tools. Copper wire is much more efficient than aluminum. If a length of copper wire and a length of aluminum wire are of the same diameter, at any given voltage more current will flow through the copper. So a motor wound with copper will provide more power than one of comparable size wound with aluminum. Copper wire, however, is considerably more expensive than aluminum, so while it contributes to the power of a professional tool, it also contributes to the higher price.

ower tools that are worked hard and continuously are susceptible to overloading and heat buildup. Several methods are used to compensate for this in professional tools. For example, the wire is insulated with a substance that resists high temperatures. Also, after the wire has been wrapped around the commutator and the armature, resin is dripped onto the windings. This resin finds its way by capillary action into the coils and coats every wire, bonding the wires together into a solid unit. At high temperatures and speeds that can go to 25,000rpm, the resin prevents one wire from rubbing against another and causing a short circuit, as well as guarding against the entry of dust and grit. In some superior professional tools, the resin will be topped with a winding of tape or some other coating to keep abrasives from wearing away the wire insulation.