ToolMaster TM-U3 - Twist Drill Grinding Attachment Setup; Setup Operations for Twist Drill Grinding

Twist Drill Grinding Attachment
The twist drill grinding attachment has been designed for grinding twist drills of 3 to 16mm (18” to 58”) di-
ameter. The tip angle is always 116 , while the back rake angle is adjustable as required.
To mount the attachment (see Fig.. 2), attach a 12 mm spring collet to locating pin land insert the collet Into
the index head slide of the index head bracket, introducing retaining pin 2 into hte bore of the offside set-
tinggauge.Adjustablestop5hasaatfurfaceononesideforholdingtwistdrillsof3to16mm(1/8”to5/8”)
diameter. The drill is held by hand against stop 5 and the swivel-mounted V-guide 4 during grinding (Fig.l).
After backing off clamping screw 7, stop 5 with ring 9 can be pulled off’’(depress catch 10) and mount ina
reverse position. This permits the clamping of small drills (3 to 6mm or18” to 1/4” dia.) by means of clamp-
ingscrew6,since‘experincehasshownthatsuchdrillsaredificulttoholdbyhandgrinding.
Setup Operations
i 1. Release clamps K3 and K4. Hold index drum T4 against stop by means of the knob and set swivel arm
at 13 . Retighten clamps K3 and K4.
2.Release clamp K2 and set swivel arm at zero on the setting scale T2 (resulting in a normally suitable
rake angle). If larger or smaller rake angles are required, adjust swivel arm accordingly. Retingten clamp
K2. Release clamp K6 and screw D6. Move index head slide T until its front face roughly coincides with
the front face of cross slide Q.
3.Retighten clamp K6 and screw D6
If new grinding wheel is used :
4 Release clamp K5, move cross slide Q fully to the right using knurled screw S5. Retighten clamp K5.
Release clamp 3(on attachment) and adjust swivel-mounted V-guide 4 until the scale shows the diam
eter of the twist drill to be ground. Retighten clamp 3.
5.Release clamp K1, and tighten clamp K. Move Index head bracket on the tubular guide until gauge plate
8 is position approx .04” laterally to the face of the grinding wheel
6.Align vertical swivel mount index mark with the reference line of the tubularguide, then retighten clamp
K1 and release clamp K3. `
7.Place test drill on V-guide K4. Back off clamping screw K7 and advance stop K5 until the cutting face of
the drill rests against gauge plate K
8, projecting approx. 0.02”(.5mm). Tighten clamping screw K7,
When using the adjustable stop in the reverse position (for small twist drills of 3 to 6mm 18” to 14” dia.),
tighten clamping screw K6.
Setup Operations
8.Swivelthetwistdrillgrindingattachmentupwards.UseneadjustmentscrewFtoadvancethedrilluntil
itcontactsthegrindingwheel.Grindtherstcuttingedgebyswivellingtheattachmentdownwards
(Fig. 3). Repeat feed and grinding operation If required.
9.Place twist drill into V-guide 4 in 180 inverted position and grind second cutting edge leaving the attach
ment and the adjustable stop in the previously used position
(i.e.notadvancingneadjustmentscrewF.)