Page 893 - Tungaloy Catalog

Regrinding Procedures
(3) Honing
Fig.3 Honing
• The honing angle θ and width H will vary depending on the
drill type, diameter, and work material. Recommended honing
specifications are given in the Table below.
• Honing procedures (refer to Fig.3)
(1) Round the R portion shown in Fig.3 in large. But, do not round R
it for DSC-F, DSC-FQ, DMX-F and DMX-FQ type drills used for R
cast irons and aluminum alloys.
(2) Then, roughly hone the cutting edge lines by using an electro- DSC DSX, DSE, DSS, DSC-F, DMX-F
DMX
DSC-FQ, DMX-FQ
deposited diamond file of around 170 grit.
(3) Carry out finish honing by using a diamond hand stick of 400 to H
600 grit.
• For DSC type drills, there is no need to hone the thinned portions. θ Rake face
R0.01
• For DSX, DSE, DMX and DSS type drills, hone the R and thinned Relief face ~0.02
portions uniformly. A A A-A section
• For DSC-F, DSC-FQ, DMX-F and DMX-FQ type drills, hone the
thinned portions uniformly.
• The honing width should be changed depending on the drill
diameter. For smaller side of diameters, the width should be in
smaller side of values given in the table.
Honing specifications for DSX, DSE, DSC, DMX and DSS
• Round the R portion in large.
Table 3
~ ø6 mm ø6 ~ ø10 mm ø10 ~ ø16 mm ø16 ~ ø20 mm
θ -20º -20º -20º -20º
Mild steels
H 0.08 ~ 0.10 0.10 ~ 0.12 0.12 ~ 0.15 0.15 ~ 0.20
θ -20º -20º -20º -20º
Hard steels
H 0.05 ~ 0.07 0.08 ~ 0.10 0.10 ~ 0.12 0.12 ~ 0.15
Honing specifications for DSC-F, DSC-FQ, DMX-F and DMX-FQ
• Do not round the R portion.

~ ø6.0 mm ø6.1~ ø8.0 mm ø8.1 ~ ø10.0 mm ø10.1 ~ ø16.0 mm
θ -10º -10º -10º -10º
Grey cast irons
H 0.03 ~ 0.05 0.04 ~ 0.06 0.05 ~ 0.07 0.06 ~ 0.08
Ductile cast irons θ -25º -25º -25º -25º
H 0.05 ~ 0.07 0.06 ~ 0.09 0.08 ~ 0.11 0.10 ~ 0.12
Aluminium alloys θ Without
H Without 11
θ = angle, H = Honing width

After regrinding, check the following before use.
• The difference of the lip height is kept within 0.02 mm. Drilling Tools
• Any damaged portion on the cutting edges is not left.
• Cutting edges are properly honed.
• Any grinding burr is not left.

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