We sell what we know, not everything

Compact Weems Parallel Plotter

A smaller version of our traditional rolling plotter. Great for use on coastal strip charts, chart books or on small chart boards and tables. The 8" x 2" plotter, mounted on a marine aluminum roller assembly, contains a semicircular protractor, distance scales of 1:20,000 and 1:40,000, as well as an inch scale. Recommended for use in conjunction with the Weems & Plath® Vecta-Rose for folded charts. Wt. 3 oz

Item # 060
$28.95 + shipping

Weems Parallel Plotter

Our most popular plotter!
The instrument consists of a plotter mounted on a roller. The plotter contains distance scales at 1:20,000,1:40,000 and 1:80,000 to fit the N.O.S. Coast and Harbor Charts and also an inch scale. A semi-circular protractor is included for measuring courses and bearings against a meridian on the chart, and two quarter circle protractors for measuring courses and bearings against a parallel of latitude. Courses and parallel lines are transferred and kept parallel by means of two rollers which are mounted on a slide axis. Used for measuring or laying off courses and distances on a nautical chart. Instructions included. Wt. 5 oz.

Item # 120
$29.95 + shipping


This navigation tool is versatile and can be used to lay off a course or a bearing, measure distance between any two points, plot a position on a chart from a given set of coordinates, or determine the coordinates of a position on a chart.  It is an updated version of the Breton and Portland Plotters.  Pencil and sharpener included.

Item # 255
$26.95 + shipping

7" Matte Nickel Divider

This lightweight matte nickel plated, brass divider is ideal for all applications. 

Item # 261
$27.95 + shipping

Ultralight Dividers/Compass

These robustly built dividers weigh only 3 oz. and are heftier than standard size dividers. Made of a coated marine alloy to resist corrosion. Gear synchronized arms allow one hand use and provide excellent point alignment while the center wheel/extension bar construction allows for fast action and precision adjustments. The Weems & Plath® Ultralight features hardened stainless steel points and are fully adjustable. Or, replace a point with lead (supplied) and you have a navigator's compass.

Item # 176
$23.95 + shipping

Parallel Ruler 15" Brushed Aluminum Arms

15 inch length, 0.22 inch thickness, aluminum arms and handles. Wt. 7.5 oz.

Item # 141
$28.95 + shipping

Parallel Ruler 12" Brushed Aluminum Arms

12 inch length, 0.22 inch thickness, aluminum arms and handles. Wt. 5.5 oz.

Item # 140
$24.95 + shipping

Light Pen

This unique pen has a small green LED tucked into its tip right next to a high quality medium ball point, just give the top of the pen a twist and you will be able to see what you are entering in the log on those long dark nights without having to light up the whole cabin. Comes with a clear cap to help prevent leaving it turned on by accident, also allows you to clip it to your chart or pocket if you just need a small light to see by. Runs for hours on end using 2 LR44 1.5 volt batteries located in the top.

Item # 1121
$8.95 + shipping

Navigator's Pencil

We feel this mechanical pencil is perfect for the navigator. It has a super fine eraser that won't mar your charts when making corrections, which adjusts out as you wear it down similar to the way you adjust the lead on the writing tip.

Item # 1141
$15.95 + shipping

Sharpening Pad

A handy addition to your navigation kit for keeping the proper point on pencils and compass leads.

Item # 92323
$6.95 + shipping

Nautical Slide Rule

Gives immediate solution to all speed-time-distance problems. Equally applicable for nautical or statute miles. Speed in knots or m.p.h., time in hours, minutes or seconds, distance in nautical or statute miles (or yards if desired and if speed is in knots). Easy to read and accurate. Standard in U.S. Navy.

Item # 105
$27.95 + shipping

Universal Plotting Sheets

These are also known as VP-OS sheets. A graduated circle printed at the center allows meridians of longitude to be constructed for any latitude, thus creating a custom-made chart for any geographical position. Available as a 50-page Plotting Sheet Pad.

Item # 5910
$10.95 +shipping

Primary Navigation Set

All the basics for charting and navigation functions. This mix of plotting tools is a tremendous value. Features our best selling #176 Ultralight Divider along with our #140 milled 12" parallel rulers for accurate course lines, #105 Nautical Slide rule for speed and distance calculation and a navigator's pencil.

Item # 32200
$79.95 + shipping


Finally, a way to keep those navigation tools neat, organized and ready to go aboard anywhere. This portfolio is designed to hold a wide variety of Weems & Plath® plotting tools. The NaviTote's heavy, 10 oz. khaki colored canvas is attractively finished with navy blue piping, nickel plated grommets and web tape handle. Designed for carry on use, or can be hung on the bulkhead.

Item # 325
$32.95 + shipping


ROADrule® USATONS (#290) identifies the most common U.S. aids to navigation, rules of the road, and maneuvering and warning signals for U.S. waters. This simple to use identification tool shows the actual view of maritime buoyage systems with corresponding chart symbols. It describes bridge lighting and Intracoastal Waterway markings. ROADrule® takes a large amount of complex information and makes it easy to understand and quick to refer to. Whether in a classroom or at the helm, critical decisions can be made quickly and with confidence with the aide of ROADrule®.

ROADrule® is constructed of durable two-sided black PVC. Its design is similar to a slide-rule. The various buoyage markers are drawn in color to match the chart symbol. This quick reference tool is a great value, is stored in a vinyl sleeve and fits nicely in a chart table. Dimensions: 16" x 5 ¼".

ROADrule® complements the recently introduced LIGHTrule® COLREGS that has become an instant success. We have also expanded the line to include three additional recognition tools and study aids that cover European inland Canals and International Waters.

Item # 290
$38.95 + shipping

The Paralock Plotter

Weems & Plath has developed the Paralock Plotter, a new parallel rule in a compact size that is particularly suited for use on modern small chart tables. The primary purpose of the Paralock Plotter is to enable the transfer of GPS positions rapidly, easily and accurately to any paper chart. The Paralock Plotter features three unique design concepts: a locking knob that allows the user to quickly plot a GPS position on paper charts, two sets of finger holes that enable finger tips to act as friction pads on the underlying chart, and, although shorter than standard size rules, the Paralock Plotter opens to the same width as conventional rules and therefore covers the same chart area.

The most inventive feature of this patented device is the locking knob located at one of the four pivot points of the rule’s cross–arms. This knob enables the two rulers to be fixed in any given separation which allows rapid determination of GPS position. The Paralock Plotter is only 7.25" long as opposed to the standard rule length of 15", but its opening width is the same as standard rules. Placing finger tips in the twin finger holes allows easy operation of the rule and readily informs the operator if a slip has accidentally occurred while aboard a rolling or pitching vessel. The Paralock Plotter is made of sturdy, clear acrylic for maximum chart visibility. It has graduations so it can be used as a protractor to determine compass bearing. It also has a millimeter metric scale across the bottom, making it is easy to take distances and transfer them to a mileage chart.

The Paralock Plotter has all the features of a standard parallel rule but fits in a pocket and is easier to use. It is perfect for any boater who keeps track of latitude and longitude coordinates on a paper chart. Its compact, convenient size makes it the right tool for use on boats with limited chart space.

Weight: 3.4 oz. Dimensions: 7.25", 18.5cm long

Item # 090
$35.95 + shipping

Professional Brass Pencil Compass

This large solid brass compass is perfect for the professional navigator using large charts. Because of its length, with adjustable pencil mount and angled stainless steel point, it can draw a 24" circle. The compass was designed by Weems & Plath and made in Germany by a company well-known for its precision instruments. The compass comes with a pencil, a sharpener and a plastic pouch for safe storage. It has a lifetime warranty.

Weight: 145.15g Dimensions: 20.95cm x 3.175cm

Item # 1049
$74.95 + shipping

Telescoping Chart Case

THE PERFECT STORAGE SOLUTION FOR CHARTS ON AND OFF THE BOAT. Not just a tube; it's a real CASE! The reinforced rib design provides strength and the twist-lock telescoping feature easily adjusts to accommodate chart lengths from 24" to 47". The 3" diameter offers ample storage space. Each case has an adjustable shoulder strap and threaded cap for security.

Item # 080
$27.95 + shipping


--New innovative design for day and night use.
--Red LED light built into each leg for use in low light conditions.
--Center adjustment mechanism allows quick, precise operation.
--Tool functions as both a compass and divider.
--Battery lasts approximately 20 hours with lights on.
--Uses one CR1220 battery.
--Spare point, lead and knob provided.
--Complete instructions included in package.

Item # 276
$44.95 + shipping