BGS technic BGS 3200 User manual

BGS technic KG
Bandwirkerstr. 3
D-42929 Wermelskirchen
Tel.: [phone]
Fax.: [phone]
[e-mail]
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© BGS technic KG, Copying and further use not allowed
BGS 3200
Drill Grinding Attachment for Twist Drills
Dear customer,
Please familiarize yourself with the proper usage of the device by
reading and following each chapter of this manual, in the order
presented. Keep these operating instructions in a safe place for
future reference. The operating instructions contain important
information on commissioning and handling. Enclose the
instructions with the product when handing over to third-parties!
Please also read all safety instructions! These should make the
correct use easier and help you to prevent misunderstandings and
damage.
SAFETY NOTES
To avoid malfunctions, damage and health impairments, please observe the following notes:
•Persons with restricted physical, sensory, or mental capabilities may not use the device unless
they are supervised by a person who is responsible for their safety or have received instructions
from the responsible person in how the device should be used.
•Wear suitable work clothes, tie long hair together and do not wear any jewellery in order to
prevent them from getting caught by moving parts.
•Always wear safety glasses when grinding.
•Always hold the drill bit tight and wear work gloves to protect against injury.
•Check the state and fixing of the protective equipment and never remove any mechanical or
electrical protective equipment.
•Do not work with a damaged grinding stone. There is a risk of injury. Replace a damaged
grinding stone immediately.
•Also observe these safety instructions when using the grinding machine.
•Do not grind damaged or broken drill bits.
•Do not use the drill grinding attachment if it is damaged.
PREPARATION
Unpack the twist drill grinding attachment and check the parts for potential transport damage.
For the grinding itself, you need a normal firmly mounted grinding machine (e.g. double grinder). Use
a fine grinding disc or a grinding disc for carbide. Mount the drill grinding attachment in front of the
grinding stone such that the drill bit can be conveniently guided to the grinding disc.
MAINTENANCE, CLEANING AND STORAGE
Thoroughly clean the drill grinding attachment after each use, and remove the grinding dust.
For cleaning, use only a dry cloth. Do not use any cleaning agent containing solvents, industrial
alcohol or alcohol.
Do not immerse the attachment in water and never expose it to any moisture!
Keep the attachment and, in particular the adjustment screw free from oil and grease.
Change a damaged grinding stone immediately otherwise there is a high risk of injury.

BGS technic KG
Bandwirkerstr. 3
D-42929 Wermelskirchen
Tel.: [phone]
Fax.: [phone]
[e-mail]
www.bgstechnic.com
© BGS technic KG, Copying and further use not allowed
STRUCTURE
No.
Designation
No.
Designation
1
Spring mounted attachment
9
Slotted base
2
Bit tray
10
Horizontal swivel bearing
3
Bit stop
11
Swing axis
4
Adjustment screw
12
Thumbscrew
5
Control screw
13
Bit lip stop
6
Feed slide
14
Bit tray tip
7
Feed slide lock screw
15
Grinding disc
8
Wing nut
MOUNTING
1. Firmly mount the grinding machine, e.g. on a workbench. In doing so,
make sure that sufficient space is available at the side of the grinding
machine for the installation of the drill grinding attachment. In addition,
the grinding disc protective cover disc must be adjusted to enable the
free area of the grinding disc to be opposite the drill grinding
attachment. The drill bit should be sharpened by an area of the grinding
disc that is on the left of the drive hub of the machine and which is
preferably at the same level or slightly lower than the drive hub of the
grinding machine
2. Position the drill grinding attachment in front of the grinding disc and
parallel to the grinding disc. Mount the drill grinding attachment with a
wing nut (8) onto the workbench (distance to the grinding disc approx. 6
cm). If necessary, insert a spacer (wood) in order to obtain the correct
height to the grinding disc.
3. To determine the correct distance from the grinding disc, if necessary,
insert a drill bit and fit the attachment exactly in front of the grinding
disc.

BGS technic KG
Bandwirkerstr. 3
D-42929 Wermelskirchen
Tel.: [phone]
Fax.: [phone]
[e-mail]
www.bgstechnic.com
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USE
1. First, select the desired grinding angle by using the thumbscrew (12) according to the intended use
of the drill bit:
59° - general use
88° - thin materials, prevents tearing
68° - for thin drill bits with fast feed
49° - for soft metals such as copper, lead, soft alloys
41° - for countersinks
2. Loosen the feed slide (6) with the screw (7), turn back the adjustment screw (4) completely and
then insert the drill bit. The bit must protrude beyond bit tray tip (14) with its point
at a dimension equal to its diameter.
3. Now firmly tighten the feed slide lock screw (7) and the attachment screw of the
attachment (1) sightly, only enough that the drill bit is just held. Make sure that
the spiral groove of the drill bit rests against the stop.
4. Loosen the wing nut (8) in the foot of the drill grinding attachment and move the
attachment in order to achieve a offset of the drill point of approx. 0.5 mm from
the grinding disc. Tin doing so, the bit tray tip (14) must be positioned precisely
vertically in front of the grinding disc.
5. Slightly loosen the control screw (5), switch on the grinding machine and push the drill bit forward
by turning the adjustment screw (4) until the drill bit touches the grinding disc. Then swing the
entire attachment (hold at the feed slide) to the right. This will automatically create the correct cut.
View from above
As the swing axis (11) is not exactly situated in the centre of the bit tray (2). This “inaccuracy”
effects right edge grinding and relief grinding. Therefore you have to swing the swing axis (11) to
the right only.
Depending on the degree of wear of the drill bit, push the drill bit further forwards by using the
adjustment screw (4). However, this should be done slowly in order to prevent the drill bit from
overheating and becoming annealed soft.If longer grinding is necessary, take breaks for cooling
down. After grinding one side of the drill bit, screw the control screw (5) tightly. This defines the
same position for the other flank.
6. Loosen the lock screw of the attachment (1) and take out the drill bit. Turn it, so that now the other
flank rests against the stop. Turn back the adjustment screw (4) and repeat the grinding process
for this flank. If the drill bit is heavily worn, repeat the grinding process.
If this still does not achieve the desired appearance of the drill bit point, repeat the grinding with the
drill bit pushed out further beyond the stop (by more than one drill bit diameter). See further
instructions about the correct sharpening of drill bits in the chapter below.
Grinding Disc
Do not swing!
Swing

BGS technic KG
Bandwirkerstr. 3
D-42929 Wermelskirchen
Tel.: [phone]
Fax.: [phone]
[e-mail]
www.bgstechnic.com
© BGS technic KG, Copying and further use not allowed
CORRECT GRINDING, CAUSES OF FAULTS AND CORRECTION
•Despite machine assistance using the pre-set grinding angles and movements, the correct grinding
of a drill bit requires some experience, and in-particular, care during the handling of the drill bit.
•Below you will be provided with several hints about the correct grinding of the drill bit and how to
avoid faults. However, this information cannot guarantee the correct grinding of the drill bit – in the
end, your own skill, adherence to the operating instructions, the state of the drill bit and the
grinding disc will determine the result
DEFINITIONS
•Do not touch the drill bit tip after grinding! There is a danger of burns!
•Before carrying out any work on the device, switch off the grinding machine and pull out the mains
plug from the socket. Do not carry out any work while the machine is running!
•Do not grind for too long. Check the grinding process at regular intervals! Reduce the pressure on
the drill bit during grinding.
•Drill bits with a large diameter must be ground for longer until they are sharp again. Grind both
sides alternately in several short sessions.
•Allow the drill bit to cool down between sessions, or cool it in water.
•If the tip has turned blue, it has been overheated during grinding. Cool the tip in water.
•If the tip is not in the centre (one flank is sharp, the other is not), regrind the shorter
flank. This fault is avoided by uniform pressure on the drill bit during grinding on both
flanks as well as identical grinding times for both flanks.
•In particular for drill bits with large diameters and major wear, grinding with the drill bit
sharpener may, under certain circumstances, not lead to a satisfactory result. Observe
that the attachment is mainly intended for periodical re-sharpening but not designed for
the complete re-working of much worn thicker drill bits.
The angle of the tip is adjusted by the predefined grinding angle and the swivelling range when
grinding.
The tip angle may deviate depending on the material.
Aluminium: 130 - 140°
Copper, brass: 120 - 130°
Steel, cast iron: 110 -120°
Plastics: 50 - 90°
Tip angle
125 – 135°
Grinding angle
h 8 – 12°
Grinding angle k
Adjustable with
the
thumbscrew (12)
Incorrect
Edge curving
backwards
Incorrect
Edge curving
forwards
Correct
Cutting
edge
Cutting
edge
Tip
Grinding angle