No. 39  Universal Thread Ginding Machines

These fully universal machine used conjunction with the wide range of ancillary equipment available are applicable to almost every aspect of precision thread grinding. Annular forms can also be ground.
Large quantity production or specialized applications can be undertaken with equal facility.
Plunge or traverse grinding techniques can be employed, using single or multi-ribbed grinding wheels.
Threads of practically any from single or multi – start, right or left hand, parallel or tapered can be ground in addition, worm forms can also be produced.
A relieving mechanism incorporated in the basic machine enables taps, thread milling cutters and similar components to e ground.
So supplement inherent versatility, a large range of wheel forming equipment is available.

Specification:

                                                                         No.39 machine                          

Maximum length between centres                          508mm 20in                              
Maximum length ground at one setting                  482mm 19in                              

Maximum diameter admitted                                                    254mm 10in
maximum diameter swing into gap                                             305mm 12in
maximum helix angle                                                              45⁰ right or left hand
Pitch range                                                                           0,42 to 305mm lead 60tpi to 12in lead
Workhead speeds (forward)20                                                   0.2 to 60 rpm
Return speeds                                                                       25.4 80 rpm or same as forward speed
Grinding wheel spindle speeds                                                   850 or 1310 or 1540 rpm
Grinding wheel size (standard)                                                  406x25x205mm bore 16x1x8in bore

Maximum taper on diameter                                1 in 8                                                      1 in 12

Relief (variable up to )                                                            5mm 0.2 in
Maximum chaser length                                                           254mm 10in
Wheelhead motor                                                                   4.4/2.2kw 6/3 hp
Crushing motor                                                                      0.25 kw 1/3 hp
Gearbox motor                                                                      0.55kw 3/4 hp