This new tool is great, NO, fantastic for removing the dents in any size trombone slide, French horn slide or other small tubing for "P.C." (playing condition) jobs or Complete Overhauls and is especially handy for RENTAL and Rental Returned instruments to keep costs down, especially these days, primarily by saving you time.  Time has always been at a premium, you only get so much!
               The more you can do within it, the better off you are.
     Now everyone knows that the trombone slide has, in addition to the regular tuning slide and other tapered tubing, A HAND SLIDE that can get damaged and needs precision repair or it won't work.   If you have a tool that can, in a precision way, remove dents and straighten the tubing; then, think how good it must be to do Trombone slides (without a problem), with such a tool.
     This NEW P88 tool completes the evolution of the tubing technology that started with the N11 Expandable trombone tool and N12 burnishing ring back in 1962 and goes through the N87 trombone slide dent rollers, the New N87A trombone pliers and now, these new P88 centerless ground mandrels, which are graduated in precise five thousandth step graduations.  These mandrels provide and maintain all of hand the precision that you have always wanted.
     These fitted, centerless ground, hardened steel mandrels are perfect for use with the N87A Trombone Pliers.  The standard N53 and metric N52 trombone mandrels we have all used for the last 60 years or so have worked well, but they were still about .015" apart; it was the best anyone could do during that era.  Now, you will always be within .005" of the tubing size, not .015" or so, that is about THREE TIMES MORE ACCURATE than before. 
     Since the late 40's Cliff has been searching for a better way to fix trombone slides and because the trombone slide is the most challenging part of Brass Repair (even more so than the valves, which are now fairly easy thanks to the N28 ground valve mandrels and the N58 ground valve sleeves).
     When you were trying to take a dent out of a slide, the mandrel or slug would always be too loose in the slide because it was TIGHT going through the soldered areas at the top of the slide from both the soldered on stocking or ferrule sleeve and the brace flange areas.  That is how and why the N11 Expandable Trombone Tool was born back in the early 1960's; so you could go down into the slide and expand to the actual size of the tube.  Since the stockings were soldered both at the top and at the bottom and the brace was soldered in the middle, there were 3 places where it was actually smaller than the regular slide tube itself, where MOST kinks, dents and pin dents happen..
     Today, most slides either have an opened swedged open end, into which the inner slide is inserted or they have a soldered connection using a ferrule tube to re-enforce the area, unfortunately the soldering makes the inside of the tubing smaller.  To solve this problem most Repairmen used some little mini slugs to try and sneak in, or Cliff's early 1960's N11 expanding tool to expand up to the  proper size after entering the slide, passed the shrunken soldered area.  Then, using GREAT CARE to carefully burnish out the dent or kink.
     On outer slides, you may have to remove the bottom bow, depending on how badly sprung the slide rails or bow tubing was.  Why, because you very seldom get a dent in a tube that doesn't also bend the slide tubing in the process.  You may not have to do this on all horns, but likely half will require it to get them perfectly correct.
     Also, with these new mandrels being within .005" instead of  .015" you will be able to do a better job than ever before because you are using rollers instead of a burnisher.   The rollers roll on both sides of the tube at the same time, so there is no bending while taking the dents or damage out.  With a burnisher, the action that makes a burnisher work also bends the slide mandrel, just like the older rollers that mounted in the vice.  This was especially true of the rollers, mounted "truck jack" fashion, even thou made or nylon or aluminum, they still bent the long mandrel.   Many repairmen replace their mandrels on a regular basis for this reason.  The N87A trombone pliers NEVER bend a mandrel!  There is no torque applied to the mandrel.

       FAST, Efficient and Profitable.                 Things we all look for.
       
     Shown with adjustable safety stop.           2 different diameter handles in 2 lengths

     There are 34 sizes of mandrels from .440" to .605".  They are numbered as such.
#1 thru #12 (.495") take the small handle and #13 (.500") and up take the large handle.
     The long handles are for trombone work, the short ones are for tuning slide work.
You will need one mandrel for the inside slide and one for the outer slide.  But, remember that many brands of trombone use the SAME SIZE bore side or inner slide size.  For example: A Blessing, Besson and Bundy all use the .495", inner mandrel.  But, for the outer slides, the Blessing uses the .525" the Besson a .530" and the Bundy uses the .535".  Thicker stockings!  (See chart below.)
     Order mandrels by size.  Ex. P88-525, for instance.

The cost of the short handles (1 large, 1 small) is $49.50+s/h

The cost of the long handles (1 large, 1 small) is $69.50+s/h

The cost of each hardened steel mandrel is $37.50+s/h

~Some Popular sizes, before the Asian Invasion~
  (sometimes fit .005" undersized, to fit in tube)

Bach: Mercedes B36,TB200.   .520" (.525")                             .555"
           36.                                    .525" (.530")                             .555"
           42,42B.                            .540" (.545")                             .575" (.580")
           50,50B.                            .555" (.560")                             .590"

Besson: 637, 937.                    .495" (,500")                              .530"

Blessing: 128                            .495" (.500")                              .525" (.530")

Bundy: 1523, (Bach TB300)  .495" (.500")                               .535"

Conn:  14H, 17H.                      .480" (.484")                              .520" (.525")
            16H, 18H, 24H.             .495" (.500")                              .535"
             6H, 48H, 77H, 100H.   .495" (.500")                              .545"
             50H, 7H, 78H.              .520" (.525")                               .555" (.560")
             8H, 88H.                        .540" (.545")                              .580"
             72H.                               .560" (.565")                              .595"

Getzen: 1050, 351.                  .495" (.500")                              .530"
               1025, 451upper.        .520" (.525")                              .555"
               1047, 451lower.        .545"                                             .580"
               1062upper.                .560"                                             .590" (.595")
               1062 lower.                .575"                                             .605"
 

Holton: TR602,511,512,513.   .495" (.500")                              .530" (.535")
              TR680,TR150.             .535" (.540")                              .580"

Jupiter: 432L.                            .495" (.500")                               .535"
               532L, 536.                   .520"                                             .550" (.555")
               636L, 636RL.               .540" (.545") .                            .580

King: Old 2B.                                .475" (.480")                             .515"
          2B (2102)upper.               .475" (.480")                             .515"
          2B (2102)lower.                .485" (.490")                             .525"
          605.                                     .480" (.485)                               .520" (.525")
          606,1506, Tempo.             .495"                                            .535"
          2115.                                    .495" (.500")                             .525"
          3B (2103, 2103F).              .505"                                           .540"
          607F,2125,2125F.               .525"                                           .550" (.555")
      4B 2104 (F),5B 2105, 1480.  .545" (.550")                             .575" (.580")
          6B(2106), 7B(2107),
                   8B(2108).                 .555" (.560")                                .595"

Olds/Reynolds(Norlin):
     A-15, TO58. Upper                .480" (.485")  (L15,T15,S15)    .520" (.525")
     A-15, TO58. Lower                .495" (.500")  (L15,T15,S15)    .535" (.540")
     A-20.                                        .495" (.500")   (V20,O20,R15)  .530" (.545")
     P-22.                                        .560" (.565")                                 .600"

Reynolds: See Olds/Norlin       Reynolds of Cleveland,OHIO you must measure.

Yamaha: YSL352,354.                .495" (.500")                                  .530"
                YSL321, 322, 421.       .560" (.565")                                  .595"

     The above list is approximate and personal preference was allowed for.
Starting in a damaged tube is variable, approximately .005" was allowed.

              Ferree's Tools-"the most copied tools in the world"