Pro-Grip Comparison Testing

Tests were made of the non-skid performance of
several candidate materials to be used as non-skid
on small boats.

Procedure:
The test equipment included a windsurfing shoe
presently found to perform well both on wind
surfers and trapezing on a Contender. The shoe
was weighted with some lead weights near the
toes which together with the shoe weighed 2
kilograms. The bottom (gripping) surface of
the shoe was drenched with water ahead of the
test.

A spring scale was hooked to a convenient loop
on the heel of the shoe and tension was applied
horizontally to the shoe to cause the shoe to slide.

The material under test was continuously watered with
low velocity fresh water from a garden hose.

Tests were performed on material identified as Pro Grip
3 mm thick, on a similar looking and feeling material
identified as ethylene vinyl acetate (EVA) 1.5mm thick,
on an unvarnished redwood plank, on the shiny and
varnished bow of a Contender and on the moulded in
non-skid on a fibreglas Contender built in 1979.

Data is presented both as measured and also converted
into a coefficient of friction.

Normal force: 2 kg

gil_pulling _bootie
Moulded non-skid on top, Pro-Grip on the bottom
wet suit booty weighted to 2 Kg and dragged
across non-skid. Water is flowing during the testing.

Material

Force

Coefficient
of Friction

Redwood plank

1.3 kg

0.65

Moulded non-skid

1.5 kg

0.75

Shiny varnished deck

1.8 kg

0.9

Ethylene vinyl acetate (EVA)

2.5 kg

1.25

Pro grip

2.5 kg

1.25

This is a non-commercial, non-solicited plug.
There is a vendor for EVA material located in Hood River, OR. Generally they sell this to the windsurfing
industry. Gil Woolley has dropped by a couple of times to buy the material which they know as
Ethylene Vinyl Acetate (EVA). It is only available in black(back in 2000 ask for others) but it is available
in at least two thicknesses -1/8 (3 mm) and 1/16 (1.5 mm).

Europeans seem to use only the 3 mm material but Gil has been happy with
the 1/16. 1/16 is less likely to peel up due to friction between your foot or your wetsuit against the edge
of the pattern. On the other hand, the 1/8 is cushier on the knees installed on the cockpit floor.
The sheets are available apparently with or without adhesive. Gil used Weldwood contact cement applied
to both the deck and the Pro-Grip.

Nick Mockeridge purchased the material with the adhesive already in place. You still have to apply
adhesive to the deck.

You can make butt joints which are invisible so you can plan your upgrade using smaller pieces and
make it appear like on larger piece.

The sheets have been about 36 inch by 72 inch. It cuts readily with a Xacto or a utility knife. If you are
very skilled, you will cut the edges with the blade angled to leave a 45 degree bevel at the edge.

North Shore Inc
4 4th Street, Hood River, OR 97031
(541) 386-1980
padz @ gorge.net (remove spaces in address)
Website http://www.northshoreinc.com

Talk to the folks there for pricing.

You will probably have to telephone. You want to buy sheets of EVA in sheets and cut the
shapes to suit your boat. I recommend two sheets per boat.

As a final plug. Your Pro-Grip installation can cover up a multitude of sins on the side
decks. Your wet suit will not be worn out in 3 days sailing by an abrasive non–skid
and you will have much better grip between your feet and the boat.

Updated Thursday 7 December, 2006 by Gil Woolley