rise grooving systems is that the standard or straight alternate i-ise, hereinbefore set forth, is pro-rided with cross-over  sections  or cross-over  areas  disposed substan-

?0 tially 1onp•itudina11y on the drum core in alignment witn’ th•<  longitudinal  axis  thereof。    On  the  other  hand,  the

alternate  rise   bias  cross-over  grooving  is provided with a cross-over section or cross-over area which is canted or off-set  with  respect  to the longitudinal  axis  of  the drums

 core。

3,1 10,060

In order to provide the alternate rise—bias cross-over grooving system on a drum core, the desired parallel grooved sleeve 10 is s•1ected and is cut and re-assembled on the idrum core as  follows:

The sleeve 10 is cut or slit along the biased  or canted lines   140,   142,   144,  and   146。   One   entire   groove  148 is removed between tire limes 140! and  146,  and  tire sleeve 10 is  also  cut  along  the  substantially  longitudinal  lines 150 and  152。   Inn  this manner,  a plurality  of: se;;ments   are

revered, namely, a  first  substantially  semi-cylindrical  sec-  10 tion  154,  a  pair  of   complementary   wedse-shaped  seg- ments  156  'and  158,  a  second  substantially   semi-cylin-

drical section 160, and a second oair of complementary wedge-shaped segments 162 and 164。 The severed seg- ments are then re-arranged anal bolted or welded  to the outer periphery of the ‹drum  core  in  such  a manner that the wedge segments 156 and 155 are reversed or inter- changed between the semi-cylindrical sections  154  and 160,  and  the  wedge   segments   162  and   1$4  are   inter-

changed  between  the  semi-cylindrical  sections  160  and   20

154。

Of course, the ustial  end  filler  bars  165 and  168 may be provided adjacent the drum flanges 170 hand 172, re- spectively, as is well 1:noivn, and as hereinbefore set  forth。

In this manner, the alternate rise—bias cross-over s-•ciion 2b grooving  syster。i  may  be  provided   on  a  cable   spooling drum,  hoisting  winch,  or  the like。

It will be apparent that a  grooved  drum having  a con- tinuous  groove  thereon  comprising  a  single  cross-over section  oi  helical  portion  in  lieu  of  tne  two  cross-over   30

areas  depicted  herein may  bc  construed  in a similar man-

ner  as  hercinbefore  set  forth。   In  this  instance,  it  may be necessary to cut only one pair of complementary wedge- shaped segments  from  the  master  cylinder  and  to delete a corresponding number of grooves therefrom whereby a grooving system having a single cross-over section may be provided。 Of course, in this type of grooving,  the cross- over area must move the cable through the width  of an entire groove, and the angle of the canted 。cutting• line may

be varied in accordance to provide for  the  full  groove  40 width  cross-over  in  lieu   of   the   half-groove cross-over width  depicted herein。