Issue 3
Original Version
JUNE 2014
8
7)
MOUNTING OF CUTTERS
The machine has been made to accept cutters having 19.05mm (3/4”) dia. shanks.
The following procedure is to be used when mounting cutters.
•
Lay the machine on its side with feed handles uppermost, ensuring arbor is wound down to its lowest point to enable access to
socket screws.
•
Take appropriate pilot and place through hole in shank of cutter. Insert shank of cutter into ¾” dia. bore of arbor, ensuring
alignment of two drive flats with socket screws
•
Tighten both screws using hexagon key RD4088.
ALWAYS DISCONNECT MACHINE FROM POWER SOURCE.
8)
REMEDIES FOR HOLE MAKING PROBLEMS
Problem
Cause
Remedy
1) Magnetic base
won’t hold
effectively
Material being cut may be too thin for efficient holding.
Swarf or dirt under magnet.
Irregularity on magnet contact or work-‐piece.
Insufficient current going to magnet during drilling cycles.
Attach an additional piece of metal under work-‐piece where magnet will
be located, or mechanically clamp magnetic base to work-‐piece.
Clean magnet.
Use extreme care; file any imperfections flush to surface.
Confirm power supply and output from control unit, check supply cable.
2) Cutter skips out
of centre-‐punch
mark at initiation of
cut
Magnetic base is not holding effectively.
Worn arbor bushing and/or ejector collar.
Too much feed pressure at start of cut.
Cutter is dull, worn, chipped or incorrectly sharpened.
Poor centre-‐punch mark; weak pilot spring; pilot not centred
in centre-‐punch mark.
Worn or bent pilot, worn pilot hole.
Loose bolts on motor bushing support bracket, main casting
or loose gib adjusting set screws.
See causes and remedies above.
Replace! Only a few thousandths wear permissible. New arbor bushing
is needed.
Light pressure only is needed until a groove is cut. The groove then
serves as a stabilizer.
Replace or re-‐sharpen. Sharpening service is available.
Improve centre-‐punch and/or replace worn parts
Replace part or parts
Adjust where necessary
3) Excessive
drilling pressure
required
Incorrectly re-‐sharpened, worn or chipped cutter.
Coming down on swarf lying on surface of work-‐piece.
Gibs out of adjustment or lack of lubrication.
Swarf accumulated (packed) inside cutter.
Re-‐sharpen or replace.
Take care not to start a cut on swarf.
Adjust setscrews, and lubricate.
Clear cutter.
4) Excessive cutter
breakage
Steel swarf or dirt under cutter.
Incorrectly re-‐sharpened or worn cutter.
Cutter skipping.
Slide-‐ways need adjustment.
Cutter not attached tightly to arbor.
Insufficient use of cutting oil or unsuitable type of oil.
Remove cutter, clean part thoroughly and replace.
Always have a new cutter on hand to refer to for correct tooth geometry,
together with instruction sheet.
See causes and remedies (2).
Tighten sideway.
Retighten.
Inject oil of light viscosity into the coolant-‐inducing ring and check that oil
is being metered into cutter when pilot is depressed. If not, check pilot
groove and arbor internally for dirt or apply oil externally. (Even a small
amount of oil is very effective).
5) Excessive cutter
wear
See cause and remedy above
Incorrectly re-‐sharpened cutter.
Insufficient or spasmodic cutting pressure.
Refer to instructions and a new cutter for proper tooth geometry.
Use sufficient steady pressure to slow the drill down. This will result in
optimum cutting speed and chip load.
