Hoffmann MU3-P Operating instructions

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Hoffmann Machine Company, Inc.
1386 Drexel Road Valdese, NC 28690 –USA
Ph: (828) 430 - 4510
www.Hoffmann-USA.com
Version: 01-2018
Operating and Maintenance Manual
MU3-P and MU3-PD
manual dovetail routing machine
Version: 7.205.00
HOFFMANN
Machine
Company, Inc.

Operating and Maintenance Manual
©HOFFMANN MU3-P & MU3-PD • Version 7.205.00 • 01-2018 2
1 Table of contents
2WARNING AND SAFETY SYMBOLS USED IN THIS MANUAL...........................................................3
3INTENDED USE AND OPERATION....................................................................................................... 5
3.1 Transportation and Installation ..........................................................................................................5
3.2 Technical Changes and Maintenance ...............................................................................................6
3.3 Operator and Maintenance Personnel...............................................................................................6
3.4 Equipment Owner’s Responsibilities .................................................................................................6
3.5 Change of Ownership........................................................................................................................6
4MACHINE DESCRIPTION.......................................................................................................................7
4.1 Terminology used in this manual...................................................................................................7
4.2 Machine Description......................................................................................................................7
5 TECHNICAL DATA AND SPECIFICATIONS......................................................................................... 8
5.1 Operator Environment........................................................................................................................8
6.2 Mechanical Dangers ..........................................................................................................................9
6.3 Defective equipment..........................................................................................................................9
6.4 Electrical Dangers..............................................................................................................................9
6.5 Cleaning agents and chemicals.......................................................................................................10
6.6 Remaining Risks..............................................................................................................................10
7 Noise Emissions .................................................................................................................................10
8WARRANTY AND LIABILITY...............................................................................................................11
9ELECTRICAL AND DUST COLLECTION CONNECTIONS ................................................................ 12
10 CHANGING ROUTER BITS.................................................................................................................. 13
10 CHANGING ROUTER BITS - CONTINUED .........................................................................................14
11 ROUTER BIT ADJUSTMENTS............................................................................................................. 15
12 SELECTING KEY LENGTH AND SETTING ROUTING STROKE.......................................................16
13 CALIBRATING AND USING DIGITAL DISPLAYS (MU3-PD).............................................................17
14 CALIBRATING TOP DISPLAY TO SET THE ROUTING STROKE.....................................................18
15 OVERVIEW - CENTER FENCE PLATE AND SQUARE STOP ...........................................................22
16 EXAMPLES OF JOINING ANGLES OTHER THAN 45 DEGREES.....................................................23
17 STEP-BY-STEP INSTRUCTIONS FOR 45 DEGREE MITER JOINTS ................................................24
18-A ACCESSORIES FOR MU3-SERIES DOVETAIL ROUTING MACHINES............................................25
18-B ACCESSORIES FOR MU3-SERIES DOVETAIL ROUTING MACHINES............................................26
19 ROUTER BITS FOR MU3-SERIES DOVETAIL ROUTING MACHINES.............................................. 27
20 HOFFMANN DOVETAIL KEYS ............................................................................................................28
21 HOFFMANN DOVETAIL KEYS ............................................................................................................29
22 HOFFMANN DOVETAIL KEY SAMPLE CASES................................................................................. 30
23 TROUBLESHOOTING ..........................................................................................................................31
24-A MACHINE DRAWINGS AND PARTS LISTS........................................................................................32
24-B MACHINE DRAWINGS AND PARTS LISTS........................................................................................33
24-C MACHINE DRAWINGS AND PARTS LISTS........................................................................................34
25 PNEUMATIC CIRCUIT DIAGRAM........................................................................................................35
26 TERMS AND CONDITIONS OF SALE AND WARRANTY ..................................................................36

Operating and Maintenance Manual
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2 Warning and Safety Symbols used in this manual
Operator must read, understand and follow all safety rules, symbols and operating instructions at all times.
The following symbols are used in this operating manual:
Safety Warning Symbol
This symbol warns of a possible danger.
Ignoring the safety instructions can lead to serious bodily harm
and/or damage to the equipment and/or material being processed.
Important Instructions
Instructions listed with this symbol must be strictly adhered to.
This symbol does not include a warning.
It is used to denote helpful hints and tips to improve the operation
and performance of the equipment.

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2.1 Warning and Safety Labels attached to machine
A number of important warning labels have been attached to this MU3-series dovetail routing machine for your
information and protection.
For your own safety, please take a moment to locate and read all warning labels before operating this machine.
If a label has been removed, defaced or is illegible, please contact Hoffmann Machine Company, Inc. to request
a free replacement.
Please note that not every label shown may be attached to the machine and labels are subject to change.
NEVER REMOVE ANY SAFETY OR WARNING LABEL!

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3 Intended Use and Operation
The HOFFMANN MU3-series dovetail routing machines are designed solely for manually routing dovetail keyways for
Hoffmann Dovetail Keys into solid hard and soft wood, wood-related materials such as MDF, plywood, particleboard and
certain plastic materials.
Dovetail Keyways in sizes W-0, W-1, W-2 and W-3 can be routed with the standard router motor, a larger 1,000 watt router
motor is recommended for use with W-4 router bits.
All work pieces must fall within the following dimensional parameters:
Dimension
MIN (mm)
MAX (mm)
Width
10
Unlimited
(with optional accessories)
Thickness
10
125
Length
100
unlimited
Using HOFFMANN MU3-series dovetail routing machines for any other operation or material
can result in unforeseen dangers and is expressly forbidden!
The manufacturer is not liable for any damages resulting from unapproved use or operation of the equipment. The operator
is solely responsible for any such risks and dangers.
The equipment may not be copied or dismantled for the purpose of duplication of all or part of the design or operation.
Technical changes to this equipment require the prior written consent of the manufacturer.
Any changes, additions, removal of components, etc. not expressly permitted in writing by the manufacturer will immediately
void the warranty. Any risks, dangers or damages resulting from unauthorized modifications are solely the responsibility of
the user/operator.
Adjustments on moveable components of HOFFMANN MU3-series dovetail routing machines during the operating process
are only permitted if such adjustments are required for the proper operation of the equipment and if such adjustment
procedures are outlined in this manual. All pertinent safety rules and regulations are to be strictly adhered to.
3.1 Transportation and Installation
Hoffmann MU3-series dovetail routing machines are shipped in sturdy cardboard boxes which are strapped to shipping
pallets for transport.
Carefully check outer carton for any shipping damage before accepting delivery and compare packing list with included items
and accessories. Inform shipping company and Hoffmann Machine Company, Inc. immediately of any shipping damage,
take photographs and note damage on Bill of Lading.
Remove all strapping and packaging and carefully lift machine out of its carton. To avoid possibility of injury, we strongly
recommend two people work together to lift machine and place it on a suitable table or workbench.
Clean off oil film from machine table, fences (also underside of fences and square stop) with paper towels and non-corrosive
cleaner (e.g. SIMPLE GREEN, Citrus Cleaner, etc.) before connecting electrical power and compressed air supply.
Connect machine power cord to 120 volt outlet or suitable extension cord. Always use shortest extension cord possible.
Use a suitable compressed air line and connect machine to compressed air supply. Customer is to supply male fitting with
1/4” NPT thread for pressure regulator.

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3.2 Technical Changes and Maintenance
Technical changes or alterations of any kind are only permitted if the prior written authorization from Hoffmann Machine
Company, Inc. has been secured.
Never remove safety guards and shields, remove or by-pass safety devices, switches, sensors, use or install tooling other
than originally supplied.
The manufacturer is not liable for any injuries or damages caused by unauthorized changes, removal or add-ons to this
equipment.
Only trained, qualified personnel may perform installation, set-up and maintenance procedures as well as replacement of
parts or components of any kind.
3.3 Operator and Maintenance Personnel
Machine operator and maintenance personnel may only perform activities described in this manual.
Persons working on or with this machine must be at least 18 years old, they must be thoroughly familiar with this operating
manual and they must adhere to all local safety rules and regulations. All OSHA specified rules must be followed if
applicable.
Persons working on or with this machine must wear suitable clothing designed to avoid entrapment in rotating machine
components.
No loose fitting clothes e.g. ties or shawls, or bracelets, wristwatches, necklaces, etc. may be worn when operating this
machine.
Persons with long hair must tie their hair securely and wear an appropriate hair covering to avoid entanglement.
3.4 Equipment Owner’s Responsibilities
The owner of the equipment must make this operator manual available to all machine operators and maintenance personnel.
The equipment owner must assure that all operators and maintenance personnel are qualified to work on this equipment and
that they have read and fully understand this operator manual, especially all sections pertaining to possible dangers and
safety rules.
The owner must assure that all areas of responsibility, including set-up, operation, maintenance, etc. –are clearly defined
and explained.
All responsibilities must be assigned to and understood by all involved persons to avoid the risk of injury and /or damage to
material.
The owner is responsible for the adherence to all applicable safety rules and regulations.
The owner is responsible for the proper and safe condition of the machine; he is further responsible for the proper installation
and set-up and he must provide a safe and secure work environment.
The owner must be familiar with and is responsible for the adherence to any and all local and national safety rules and
regulations pertaining to this equipment.
The manufacturer is not liable for any injuries or damages as a result of non-compliance with, or adherence to, applicable
safety rules and regulations.
If the operator and/or maintenance personnel do not understand English, the owner must provide a properly translated
operator manual to assure the safety of all personnel.
3.5 Change of Ownership
In case of sale of this equipment all components, tools, manuals, safety instructions, accessories as well as any electronic or
software updates you have originally received with the machine must be included.
This includes any and all operator manuals, maintenance instructions, equipment or components replacement parts, etc.

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4 Machine Description
4.1 Terminology used in this manual
MU3-series = HOFFMANN MU3-P or MU3-PD Dovetail Routing Machine
Bit = Hoffmann dovetail router bits in sizes W-0, W-1 / W-2 / W3
Workpiece = User supplied moulding profiles made of wood or wood related materials
Dovetail Key = HOFFMANN Dovetail Keys
4.2 Machine Description
HOFFMANN MU3-series dovetail routing machine consists of:
HOFFMANN MU3-series dovetail routing machine
45 degree center fence plate with locking lever
90 degree square stop with locking lever
One Hoffmann router bit installed
Toolkit
Operating manual
Hoffmann MU3-P pneumatic dovetail routing machine Hoffmann MU3-PD pneumatic dovetail routing machine
(shown with optional accessories) (shown with optional accessories)

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5 Technical Data and Specifications
Electrical Power Supply
Supply voltage
Frequency
Input Amperage
Motor Speed
Collet Size
Router motors
Router bits
120 volt, single phase
50-60 Hz
8 A
34,000 rpm
1/4” (6.35mm)
Hoffmann router motor Type UAD-33 885 watt –120 volt
Hoffmann Dovetail Router Bits, size W0 / W1 / W2 / W3
Compressed Air Supply:
Compressed Air Requirements
90 psi (6bar) clean and dry air
Approx. volume 1liter/cycle = 0.04 cubic feet / cycle
Other Specifications
Work piece material
Machine performance
Weight
Dim. Length x depth x height
Noise emissions:
Sound Pressure Level (SPL):
Wood and wood related materials and certain plastics
Up to 40 cycles/hour (depending on operator, material flow,
material quality, etc.)
approx. 71 lbs.
approx. 29 1/4” x 25 1/2” x 32 7/8”
75.3 dB (A)
Machine Environment
Temperature range for operation
Temperature for storage / transport
Temperature change during operation
Temperature change during storage / transport
Relative humidity according to DIN 40040
Air pressure during operation
Air pressure during storage / transport
59.... + 104 F
32.... + 140 F
max. 20 F
max. 40 F
15... 80 % without condensation at 95 F
860-1060 hPA (bar)
860-1060 hPA (bar)
5.1 Operator Environment
The work areas for the operator have been designed with ergonomic principles in mind.
The machine owner is responsible for ease of access, adequate lighting, fresh air supply, etc.
Rules for safe work areas:
The work area must be free from clutter and must be kept neat and unobstructed. Local and national safety rules,
including but not limited to all applicable OSHA Rules must be adhered to.
Access space of no less than 24” shall be available on all sides of the machine for set-up and maintenance
procedures.
All electrical supply lines must be securely fastened in accordance with all local and national safety codes. Secure
all wires, hoses and lines and do not allow lines to lie on the floor as they may present a trip hazard to the operator. Supply
lines, wires and hoses must be inspected periodically and replaced if any damage is observed.
The environmental conditions must meet the guide lines given under section 5 “Technical Date and Specifications”

Operating and Maintenance Manual
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6 Potential Sources of Danger
6.1 Unapproved Use
Unapproved procedures are:
Processing work pieces made of material other than solid wood or wood related material such as
MDF, particle board, plywood, etc.
Operating of the machine by more than one operator at the same time.
Unapproved use and/or misuse of the machine can result in the following:
Minor to severe injuries to the machine operator and/or bystanders.
Damage to the machine and/or work pieces.
6.2 Mechanical Dangers
During operation of this machine sharp router bits rotate at high speeds.
These components can cause severe injury if hair or clothing or extremities become entangled.
Never reach into the machine during operation!!
Only make adjustments during operation if these adjustments are absolutely necessary and if the
procedure is fully outlined and approved in this operator manual.
6.3 Defective equipment
If the machine does not function properly and if the fault cannot be rectified immediately, the equipment must be
shut down by the person responsible for the operation.
Signs of defective are:
The machine shows signs of mechanical damage.
Electrical wires or cables are damaged.
The machine was stored or has not been in use for an extended period of time in an unsuitable
environment, for example in high relative humidity or too high or too low temperature.
6.4 Electrical Dangers
Dangerous electrical current is present in different locations inside of the machine’s limit switch
when the power cord is plugged in, even if the machine is not being operated and the motor is switched off. Do
not remove any switch cover or motor end cap.
Never use damaged or worn cables, wires, supply lines or electrical components or parts on this
machine.

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6.5 Cleaning agents and chemicals
Review and observe all safety rules provided by the chemicals manufacturer while working with
cleaning agents and other chemicals. Read and understand the Material Safety Data Sheets (MSDS)
provided by the manufacturer and follow all safety precautions described therein.
Always wear proper protective gear, including safety glasses and gloves, when using cleaning
agents, degreaser, etc.
Do not eat, drink or smoke when using chemicals.
Dispose of used cleaning agents and other chemicals in accordance with all State and local laws.
6.6 Remaining Risks
If the operator does not pay attention, it is possible to squeeze ones’ fingers when loading and
manually clamping a work piece. Never place your fingers under the clamp pads of the material
clamp pad or in the path of the router bit.
7 Noise Emissions
The machine generates a work place Sound Pressure Level (SPL) of approx. 75.3 dB(A)
when processing a work piece.
Local conditions could increase the SPL, which could cause hearing damage or loss.
The machine owner must provide suitable protective gear to protect employees from
hearing damage, as required by local and state laws and OSHA regulations.
Notes:
All listed values are measured noise emission levels –they are not necessarily safe working environment levels.
Local conditions, the proximity of walls and ceilings, the type of wall, ceiling and floor material as well other
equipment in close proximity could affect the total noise emissions at the work place.
The SPL values are provided as information only and it is recommended that the machine owner measure the
actual local noise levels after installation.
Machine is owner is responsible for providing suitable protective gear depending on total noise emissions and
local and state laws and regulations.
All OSHA regulations pertaining to noise protection are to be adhered to.