Interpretation ID: nht88-1.2

TYPE: INTERPRETATION-NHTSA

DATE: 01/01/88 EST

FROM: SAF-TEE SIPING & GROOVING INC.

TITLE: NONE

ATTACHMT: ATTACHED TO DECEMBER 30, 1988 LETTER FROM JONES TO SPRUNK, OCTOBER 8, 1987 LETTER FROM SPRUNK TO JONES, 1978 NSC WINTER TEST REPORT, AUGUST 19, 1986 LETTER FROM KEIL TO SPRUNK, ARTICLE FROM AUGUST 1986 ISSUE OF "SCHOOL BUSINESS AFFAIRS," ARTICL E ENTITLED "SLASHING TIRES FOR SAFETY AND SAVINGS" FROM DECEMBER 1984 "NATIONAL SCHOOL BUS REPORT," MARCH 20, 1985 LETTER FROM GIFFORD TO SPRUNK, OCTOBER 15, 1982 LETTER FROM PALMER TO MARCY MANUFACTURING, AND APRIL 1983 AND APRIL 1984 ARTICLES FROM "GW SAFETY TALK"

TEXT: For SIPING mounted passenger car tires & light duty truck tires

Our model SP Saf-Tee siper is designed specifically for passenger and light duty tires which are mounted on wheels. The machine comes equipped with 12 blades along with the 4 lead screws for siping depths of 5/32", 7/32", 9/32" and 11/32", a wrench for changing the lead screws and a file for sharpening the blades. The machine also comes standard with the Universal Passenger Adapter that will accommodate any wheels that have an opening of 1.75" up to 5 1/2" center hole. This machine has recently been redesigned and the lifting height of the tire has been lowered. It is fast, easy to operate and takes less than 3 minutes to mount, sipe and dismount the tire. The machine requires very little room and operates with 110 power and air.

This machine is an excellent profit builder for a tire operation or anyone who services automobiles and light duty vehicles. With the advent of high performance tires siping is becoming increasingly popular as a way to offer these tires traction and sta bility on wet and slippery surfaces, in addition to extending the tire life.

FEATURES:

* Fast . . . entire siping process takes less than three minutes.

* Exclusive spiral cut creates "tie bars" that strengthen tread components to reduce chunking.

* 90 degrees angle cut across tire gives most traction opposite to the line of travel and desired braking vector.

* Sipes remain sharp and gripping -- can be accomplished only by siping after tire is manufactured.

* Profitable. You get repeat business from satisfied customers. You give them increased safety, reduced operating costs and better tire performance.

SPECIFICATIONS: Height 38"

Width 27"

Side Width 34"

Weight 200lbs.

Motor 1 HP, 110 (standard)

The concept of siping was first patented in the 1920s by John Sipe, who made a series of small cuts in his shoes to give him better traction. The idea is not new, but modern technology has developed siping machines to a high level of sophistication. Siping cannot be duplicated during manufacturing because it leaves a small void of rubber between the sipes. After a short period of time it becomes round and ineffective. Saf-Tee sipes cut into the tire, remove no rubber and the edges remain sharp an d gripping.

Saf-Tee siping machines cut slits at a 90 degrees angle across the tire tread, from 5/32" to 11/32" deep. These slits create thousands of sharp, gripping edges to provide extra traction, safer braking and actually extend the life of the tire as a res ult of dissipation of heat on highway travel. Siping across the tire gives the most traction opposite to the line of travel and desired braking vector.

RUNNING

Under normal road conditions: The ribs flex, responding to bumps and pits in the road, reducing shock to carcass and sidewalls. The tire runs cooler. Under wet, icy snow conditions: The ribs flex, the sharp, exposed edges cut through the hazard squeege eing the water out of the way.

ACCELERATION

Positive traction starts and acceleration in all weather conditions . . . spin on snow and ice is drastically reduced: The ribs separate and expose the sharp squeegee edges to cut to the road surface and channel the hazard out of the way. And . . . sipin g reduces tread wear, extending tire life.

BRAKING

Straight line braking: Without jacknifing, fishtailing or skids. The ribs separate, squeegeeing the hazard or road film away, giving the tire a sure-footed grip on the road surface. Siped tires greatly reduce heat buildup in braking and reduces tire we ar. Siped tires greatly reduce the distance needed to stop.

TESTS

Tests conducted by the National Safety Council on the performance of siped vs. unsiped tires on ice resulted in a 64% increase in breakaway traction and an increase of 28% spinning traction. In stopping distance tests, the reduction was from 200 feet to 155.6 feet -- a 22% improvement.

Major airline engineers tested the use of siping on ground equipment vehicles at O'Hare Field. They recorded a 25.72% increase in drawbar pull on a wet ramp flooded with glycol from deicer. They also show a 33.96% increase in braking under the same conditions. Tests were made before and after siping. As a result of these tests, they have saved thousands of dollars by reducing the need for chains on all vehicles.

The winning car in the Uniroyal One Lap of America auto rally was equipped with siped B. F. Goodrich tires. The 8,800 mile, eight-day endurance race began in Detroit, traveled through 28 states, and ended back at Detroit. Even though the driver enco untered near-blizzard conditions with snow and ice in the mountains, he had no trouble with traction. After the rally the siped tires were just like new.

Saf-Tee sipers employ a circular knife to make slits around the circumference of the tire. This causes the bottom of the sipe to form a scallop pattern, providing a varied depth and strength tie between adjoining sipes. Unlike the uniform depth cut of other siping processes, these scalloped "tie bars" reinforce tread components.

WHAT THEY SAID:

"At the present time we operate three retail stores all dealing in passenger and light duty vehicles. We have a siping machine in each of these stores and in the last twelve months our income has been $ 28,000 from siping."

-- Earl Springer, VP

Roemers Tire Centers, Missoula, MT

"On three sets of our logging tires siped at 11/32 deep the results were 40% less useage of chains, less abrasive damage to tread area and 7%-10% more mileage."

-- Larry Gifford, Service Rep.

Yokohama Tire Corporation

"Increased safety and reduced operating cost don't always go together but with Saf-Tee siped tires, they do. There is no way that I would go back to running without them."

-- Bob Beach

Beach Bus Service, Missoula, MT

"We experienced severe handling problems on snow and ice with police vehicles. In an effort to improve this performance we siped tires on several of these vehicles and ran tests. We found we could negotiate 90% comers safely on ice at 25-30 miles per ho ur after siping where previously we could control the car only at 10 miles per hour. Braking was increased in all cases by 30%."

-- Lynn L. Keil City of Billings, Billings, MT

"The improved safety record of our 44 trucks has earned lower insurance rates."

-- Jim Palmer Trucking, Missoula, MT

"Our truck and trailer tires have 20% better wear after siping."

-- Holland Trans. Co., Fargo, ND

"The traction on ice/snow covered surfaces was much improved."

-- Wayne County Sheriff, Wooster, OH

"Since the tires were siped on our tank truck, we find that braking is better. Tires last longer too."

-- Terreberry Septic Service Ltd.

Port Colborne, Ontario

Call for more information, test results, testimonials, specifications and prices.

For SIPING mounted tires from 12" to 24.5"

The Model ST is our most popular siping machine because it is a multi-purpose unit -- it can sipe any tire from 12" to 24.5". with the adapters available. It's easy to run: operators can be trained in 15 minutes. It's fast: the process takes only 3 to 4 minutes per tire to perform. Any type of tire can be siped -- new, re-cap, or used -- as long as it has 5/32" of tread left. Twelve cutting blades are furnished with the ST, along with four lead screws for siping depths of 5/32", 7/32", 9/32" and 11/3 2", a file, and a wrench for switching lead screws.

FEATURES:

* Fast . . . three to four minutes per tire.

* Versatile. Depth and width of sipe can be changed in seconds. Five depths: 5/32", 7/32", 9/32", 11/32" and 13/32". Two widths: 4 to the inch, 5 to the inch. Five angles: 90 degrees standard, and optional 45 degrees right or left, 60 degrees right o r left.

* Reliable. Machines have been in operation for over 15 years, trouble free. Siping does not affect the tire warranty of major tire manufacturers.

* Profitable. Permits servicing wide range of customers. Truckers buy their tires from dealers who offer siping services.

* Exclusive spiral cut creates "tie bars" at bottom of scalloped sipe to strengthen tread components.

* Marketing assistance. A factory-trained rep will set up the machine, instruct operators, and provide a complete promotional package to help sell siping services to your customers.

SPECIFICATIONS:

Height 42"

Width 34"

Side Width 36"

Weight 250 lbs.

Motor 1 HP,110(standard)

For HIGH VOLUME SIPING before mounting on wheels

The Model STE Siper is designed for use by a retreader, large retailer or wholesaler of tires for volume siping before tires are mounted on wheels. The STE is fast. The rim inflates in about five seconds after the operator positions the tire. The whol e process, including the siping, takes less than three minutes.

The Model STE is equipped with an expandable hub to handle rims to fit tire sizes from 13" to 24.5". Four different size rims are needed to accomodate these sizes -- one from 13" to 16", 17" to 20", 20" to 22.5" and 22.5" to 24.5". Rims are optional equ ipment to be selected depending on the tire sizes you most frequently sipe.

Twelve cutting blades are furnished with the STE, along with four lead screws for siping depths of 5/32", 7/32", 9/32" and 11/32" and a wrench for changing the lead screws.

FEATURES:

* Fast . . . entire siping process takes less than three minutes.

* Exclusive spiral cut creates "tie bars" that strengthen tread components to reduce chunking.

* 90 degrees angle cut across tire gives most traction opposite to the line of travel and desired baking vector.

* Sipes remain sharp and gripping -- can be accomplished only by siping after tire is manufactured.

* Profitable. You get repeat business from satisfied customers. You give them increased safety, reduced operating costs and better tire performance.

SPECIFICATIONS:

Height 45"

Width 42" Side Width 40"

Weight 450 lbs.

Motor 1 HP, 110 (standard)

Blades Available from Saf-Tee Siping & distributors

AVIATION GROUND EQUIPMENT SHOWS NEARLY 34% INCREASE IN PERFORMANCE AFTER SAF-TEE (registered) SIPING

This chart shows documented proof of the dramatic increase in draw bar pull that can be expected with the use of "Siped" tires. Siping can reduce the need for tire chains on all your vehicles. Chains are costly and dangerous especially on airport surfa ces. The outlawing of sludded tires made our need even greater. At United where I managed the ground equipment maintenance, we Siped all drive wheel tires, and also some front tires depending on application.

Thousands of dollars were saved by United at O'Hare by reducing the need for chains on all vehicles. They have been using Siped tires for 6 years. For economy and safety I see Siping as a must in all Airport operations.

C.N. HOSTERT

Equipment Maintenance Manager-Retired

O'Hare Field

United Airlines

TIRE SIPING TEST

GATOR TRACTOR 30500# AT 55

TEST ACCOMPLISHED USING DIGAL READOUT DYNAMOMETER ATTACHED TO REAR HITCH OF GATOR AND FRONT HITCH OF T800 WHICH WAS USED FOR LOAD. A. DRAWBAR PULL BEFORE DRY CONCRETE RAMP SIPING AFTER SIPING % INCREASE TEST 1: 14250 15000 5.26% TEST 2: 14200 15300 7.75% TEST 3: 14350 15800 10.10% AVG. 7.70% WET RAMP (FLOODED WITH RUNNING WATER) TEST 1: 11800 13200 11.86% TEST 2: 11900 12800 7.56% TEST 3: 11650 12500 7.30% AVG. 8.91% WET RAMP GLYCOL (FLOODED WITH GLYCOL FROM DEICER) TEST 1: 9750 12400 27.18% TEST 2: 9700 12160 25.36% TEST 3: 9550 11900 24.61% AVG. 25.72%B. BRAKING TEST ACCOMPLISHED STATIC BY LOCKING BRAKES ON GATOR AND DRAGGING WITH T800 BEFORE DRY CONCRETE RAMP SIPING AFTER SIPING % INCREASE TEST 1: 13000 13800 6.15% TEST 2: 13100 14000 6.87% TEST 3: 13200 13950 5.68% AVG. 6.23% WET RAMP (FLOODED WITH RUNNING WATER) TEST 1: 10700 13450 25.70% TEST 2: ? 13600 ? TEST 3: 11200 13900 24.11% AVG. 24.90% WET RAMP . GLYCOL (FLOODED WITH GLYCOL FROM DEICER) TEST 1: 8700 12270 41.03% TEST 2: 9500 12380 30.32% TEST 3: 9500 12400 30.53% AVG. 33.96%

Test conducted by United Airlines Engineers