Evening star. [volume] (Washington, D.C.) 1854-1972, 1920-09-26
CHANGE TO PNEUMATIC
TIRES MAY Be UNW|SE
Owners of Large Fleets of Trucks
Are Advised to Consult Tire
Experts as to Results,

Owners of large fleets of trucks will
do well to consult a tire expert be-
fore changing from solid to pneu-
matte tires, because in some cases
the truck is better adapted to the
solid tires. according to J. Newton
Gum, president Of the United States
Rubber Company.
The present tendency of tire man
| ufacturerS to recommend 20 truck
operators promiscuous change-overs
| from solid to pneumatic tires leads
me to offer word of caution" said
Mr.. Gum.
l. In my opinion the time has come
when Intelligent advice should be
given to the truck owners of the
country on this subject. There is rea-
| son to doubt whether truck owners
| IN changing over indiscriminately
| from solids to pneumatics understa nd
| that such a change over is not always
satisfactory and may even be harm
full to their trucks.
Governed by Conditions.
The truth of the matter is that
| there are certain circumstances under
| which it is wise for a truck owner to
| use pneumatic tires and other condi-
| tons under which it is equally wise
| to continue to use solids.
| THE chief purpose in making this
| statement at this time is to prevent
| dissatisfaction to truck owners who
attracted by the success of the big
| pneumatcs, may be contemplating
disseminating the use of solid tires
| and using pneumatic in their stead,
without inquiring into the suitability
| of the pneumaticS for their trucks or
| their particular needs. 1t would be
| well for an owner to consult with a
| tire expert before making such a
| change.
| Pneumatic tires have certain very
| definite advantages over solids. 1t
| is just as desirable to have all trucks
| operate on pneumatic tires as it is
| to have all passenger cars operate on
pneumatics. The invention of the
pneumatic tire was one of the great
est steps forward in the development
matte tire for trucks is as great
| step forward in the evolution of
motor trucks. But until trucks are
designed especially for them, truck
owners should hesitate about substi-
| tuting pneumatics for solids unless
| they are sure that pneumatics are
| better suited to their trucks and their
| needs than solids
Studied by Engineers.
Owners of heavy duty trucks the
weight of whose loads makes pneu-
| matte tires unfeasible, but who have
| been dissatisfied with results obtain
| ed from solid tires, may take comfort
| from the fact that tire engineers are
devoting attention to the solid tire
problem with an earnestness that is
| bringing tangible results.
Two chief obstacles have made the
use of solids in large sizes unsatis-
factory, both the result of the large
mass of rubber necessary to their
construction. In travel on solid tires
the traction wave formed in the rub
Der just ahead of the point of con-
tact with the road surface has caused
Isuch a kneading of the compound as
to result in the deterioration of the
rubber. The second obstacle has been
the difficulty of securing perfect vul-
lcanization throughout the entire mass
of rubber. AS a consequence of this
difficulty it has not been uncommon to
have tires fail because the heart of
the tire was improperly cured.
! Various styles of tires have been
designed to overcome these diff
culties. These styles have utilized a
groove in some instances and a slot
in others, but the results obtained
show that neither the slot nor the
groove has brought about an even
! INFLAMMATION or eliminated internal
| friction.