marposs M1 Star MBG User manual

Instruction Manual
CONGRATULATIONS TO HAVE CHOSEN
Marposs M1 Star MBG (Mechanical Bore Ga ge)
Reading this manual will enable you to use the product in the best way,
and to become acquainted with all the system characteristics that mark
it out and make it unique of its kind.

WARNINGS
In order to protract the correct operation and high quality standards of the bore
gauge, it is advisable to comply with the warnings below.
FOREWORD
The M1Star MBG mechanical bore gauge is a new-concept product, designed to
measure the inside diameter of blind or through bores in a quick and reliable way.
This product is innovative in its contents: the pioneering technology employed in its
construction ensures the utmost reliability and accuracy.
The concepts of extreme modularity on which the MBG system is based makes it possible
to meet the manifold application needs present in a normal work-shop environment.
This User Manual is supplied only for information purposes. Marposs SpA reserves the
right to change the contents of the manual without being obliged to give advance notice
of it and/or not to notify any possible modification of the product.
The descriptions contained in this manual may not be tampered with or altered by
unauthorized personnel.
For further information, we invite you to visit our website, www.testar.com, where you
can download the updated versions of the individual instruction manuals.
All the products, company names and logos are protected by copyright.
WARNING:
Do not manipulate or twist the measuring armset inside the plug gauge (see Fig. 1);
any operation that may be carried out inside it is authorized only if the appropriate tools (mentioned
in this manual) are used; otherwise the transmission system might get damaged.
WARNING:
Do not use solvents: the maintenance and/or cleaning of the plug gauge must be carried
out following the instructions contained in this manual.
WARNING:
The bore gauge must not be dropped
and/or hit: this might damage the
measurement detection system, particularly in
plug gauges for small diameters.
NOTE:
Any damage on the product and/or
relevant components due to an improper
use of the product void the Marposs SpA warranty
terms.
1

CONTENTSCONTENTS
CONTENTSCONTENTS
CONTENTS
CHAPTER 1. DESCRIPTION OF MAIN PARTS 5
CHAPTER 2. ASSEMBLY AND ZERO-SETTING OF INDICATOR 6
PENCIL PROBE 6
MARPOSS MECHANICAL/ELECTRONIC INDICATORS 8
NON-MARPOSS INDICATORS 9
CHAPTER 3. REPLACEMENT OF PARTS AND COMPONENTS 10
3.1 PLUG GAUGE 10
3.1.1 REPLACEMENT OF PLUG GAUGE 11
3.1.2 CAP REMOVAL 13
3.1.3 CONTACTS REPLACEMENT 15
3.1.4 DISASSEMBLY OF NOSEPIECE/ARMSET 19
3.1.5 DISASSEMBLY OF BUSHING, ROD AND SPRING 23
3.2 HANDLE 25
3.2.1 PENCIL PROBE HOLDER 26
3.2.2 INDICATOR HOLDER HANDLES 28
CHAPTER 4. OPTIONAL ACCESSORIES 29
4.1 THREAD ADAPTORS 29
4.2 ANGLE 30
4.3 DEPTH STOPS 31
4.3.1 ASSEMBLY OF DEPTH STOPS FOR DEPTH EXTENSIONS 32
4.3.2 ASSEMBLY OF NOSEPIECES DEPTH STOPS 33
4.4 HOOKS 34
4.5 DEPTH EXTENSIONS 35
4.6 ROTARY SPACER 36
CHAPTER 5. TROUBLESHOOTING 37
5.1 REPEATABILITY TEST 38
CHAPTER 6. MAINTENANCE 39
6.1 ORDINARY MAINTENANCE 39
6.1.1 THREE MONTHS MAINTENANCE 39
6.1.2 SIX MONTHS MAINTENANCE 39
6.2 SPECIAL MAINTENANCE 40
CHAPTER 7. LIST OF SPARE PARTS 41
7.1 STANDARD INDICATOR HOLDER 41
7.1.1 COMPONENTS 41
7.2 MINI INDICATOR HANDLE 42
7.2.1 COMPONENTS 42
7.3 PENCIL PROBE HOLDER 43
7.3.1 COMPONENTS 43
7.4 PLUG GAUGES 44
7.4.1 NOSEPIECES 45
7.4.2 MEASURING ARMSETS 46
7.4.2.1 COMPONENTS 3 - Ø< 5,5 46
7.4.2.2 COMPONENTS 5,5 - Ø< 7,5 46
7.4.2.3 COMPONENTS 7,5 - Ø< 9,5 47
7.4.2.4 COMPONENTS 9,5 - Ø< 26 47
7.4.2.5 COMPONENTS 26 - Ø- 300 48
7.4.3 CONTACTS 48
7.5 ACCESSORIES 50
7.5.1 THREAD ADAPTORS 50
7.5.2 ANGLE ADAPTOR 50
7.5.3 CAPS 50
7.5.4 DEPTH STOPS 51
7.5.4.1 DEPTH STOPS FOR EXTENSIONS 51
7.5.4.2 DEPTH STOPS FOR NOSEPIECE 52
7.5.5 HOOKSHOOKS
HOOKSHOOKS
HOOKS 52
7.5.6 EXTENSIONS 52
7.5.7 ROTARY SPACER 53
7.6 INDICATORS 53
7.6.1 PENCIL PROBES 53
7.6.2 MECHANICAL INDICATOR 54
7.6.3 ELECTRONIC INDICATOR 54
7.7 WRENCHES FOR RETOOLING/RECONFIGURATION/MAINTENANCE 55
7.7.1 WRENCHES FOR CONTACTS 55

5
DESCRIPTION OF MAIN
PARTS 1
Chapter 1 - DESCRIPTION OF MAIN PARTS
Thanks to the extreme flexibility of the MBG bore gauge, it is possible to achieve the
configuration that is most suitable to any individual requirement.
The graphic representation below identifies the main parts of the bore gauge, which will
be analyzed in detail further on.
HANDLES
THREAD
ADAPTORS
ANGLE ADAPTOR HOOKS DEPTH STOPS
DEPTH
EXTENSIONS ROTARY SPACER CONTACTS CAPS
PLUG GAUGE

2ASSEMBLY AND
ZERO-SETTING OF
INDICATOR
6
Chapter 2 - ASSEMBLY AND ZERO-SETTING OF INDICATOR
There are two procedures for the assembly and zero-setting of the indicator:
Procedure for appliances where PENCIL PROBES are present;
Procedure for appliances where MECHANICAL or DIGITAL indicators are present.
PENCIL PROBE
The operations sequence varies according to the model purchased:
a) Bore gauge WITH Marposs pencil probe (or compatible) mechanically installed and
zero set (follow SET-UP A procedure)
b) Bore gauge WITHOUT pencil probe installed (follow SET-UP B procedure)
SET-UP A
1. Connect the bore gauge at the electronic indicator by means of the connector
2. Insert the bore gauge in the master (the displayed measure must be next to zero)
3. Perform the electrical zero setting of the bore gauge, following the procedure of the
electronic system in use. Please refer to the mechanical zero setting (SET-UP “B”;
from step 7 to step 12) in case the zero setting is not obtained by means of the SET-
UP “A” procedure.
SET-UP B
1. Apply the 13 A/F wrench to the threaded connection seat “E” (see fig. 1), unscrew
and extract from the handle the measuring unit (probe holder “A” + threaded
connection “E” + plug gauge “B”, see fig. 1b).
2. Unscrew and remove the nuts from the cable-holder clamp unit using the 4 A/F
wrench, and disassemble the two semi-clamps by means of the 1.5 mm hexagonal-
end wrench (see fig. 2).
3. Manually loosen the ring nut “C” (if too tight use the 16mm A/F wrench), then unscrew
and disassemble the unit “E” + “B” from the probe holder “A” (see fig. 3).
4. Loose the tapered nut “D” and insert the probe in the relevant holder at a 14 mm
protrusion (see fig. 4). Manually screw the tapered nut “D” until its stopped.
5. Firmly apply the 10mm A/F wrench to the probe holder, and then permanently lock
the tapered nut “D” using the 15mm A/F wrench (see fig. 5).
6. Insert the connector in the handle then plug it in the electronic display.
7. IInsert the plug gauge “B” in the zero-setting master.
8. Insert the probe holder unit “A” in the group “E” +”B”. Firmly holding the unit “A”,
screw “E” + “B” turning them counterclockwise (see fig. 6).

7
ASSEMBLY AND
ZERO-SETTING OF
INDICATOR 2
9. Manually screw the ring nut “C” until its stopped, trying to maintain the zero-setting.
Firmly apply the 13mm A/F wrench to threaded connection “E”, and then lock the
ring nut “C” by means of the 16mm A/F wrench (see fig. 7).
10. Re-assemble the two semi-clamps to the relevant cable holder seats, inserting in-
between the cable (*) (see fig. 8).
11. Replace and screw the 2 nuts in the cable clamp, and lock them using the 4mm A/
F wrench (see fig. 8).
12. Screw the handle to the measuring unit (see fig. 9), and lock it by means of the
13mm A/F wrench.
13. Perform the electrical zero-setting of the bore gauge through the electronic system
in use.
(*) The pencil probes for the M1 Star (see page 53) have been manufactured with a 4,7
mm diameter cable. In case the pencil probes in use have standard diameter cables
(3,3 or 3,8 mm), it is required to use the specific tear-resistant gaiter included. Please
refer to fig. 8 for assembling.
NOTE:
The removal and/or replacement of the plug gauge may result in the loss of the zero-
setting of the bore gauge..
13A/F

2ASSEMBLY AND
ZERO-SETTING OF
INDICATOR
8
MARPOSS MECHANICAL/ELECTRONIC INDICATORS
In order to complete the bore gauge, it is necessary to assemble the display dial and to
follow the quick set-up procedure described below, which is suitable only for indicators
with Marposs characteristics.
SET-UP WITH TD1, TD10, TD1P AND QUICK DIGIT INDICATORS
1. By means of the A/F 16 mm wrench (fig. 1-A), or a 2 mm hexagonal wrench (fig. 1-
B) loose the ring nut “1” and manually unscrew the indicator-holder until extraction
from the handle.
2. By means of the hexagonal-end 2 mm wrench, insert and lock the indicator in the
relevant indicator-holder (*) at the following distances:
• 7 mm A-distance (fig. 2) in case of standard indicator holder-handle;
• until its stopped (A= 0 mm) in case of mini indicator holder-handle;
3. Apply the bore gauge to the zero-setting master (see fig. 3).
4. Re-insert in the handle the indicator-holder unit, manually screw it so as to notice at
least a 500 mm shifting of the indicator pointer (for models TD1, TD10 and Quick
Digit). For the TD1P model the indicator pointer has to be within the ±30 mm range,
in order to be sure to retrieve the ZERO by means of the mechanical potentiometer.
5. Firmly apply the 27mm A/F wrench (**) to the seat of the plug gauge handle “2”,
and lock the ring nut “1” using the 16mm A/F wrench (see fig. 4) or the 2mm
hegagonal wrench.
NOTE:
The indicators, since they are not components of the plug gauge, are not assembled,
but placed within the package.
(*) The 3/8’’ indicator-holder require the extension “B” included, to be placed
between the indicator rod and the gauge contact (see fig. 6).
(**) If the mini handle is employed it is required to use the 15mm A/F wrench.
2 A/F
27 A/F
16 A/F

9
ASSEMBLY AND
ZERO-SETTING OF
INDICATOR 2
TAB 1
L max
20 mm
L min
16 mm
L1 max
16 mm
L1 min
14 mm
L
L1
ZERO-SETTING OF TD1; TD10; TD1P AND QUICK DIGIT INDICATORS
TD1 AND TD10:
Rotate the quadrant ring nut of the indicator, until have the ZERO corresponding to the
pointer.
TD1P:
On the upper part of the indicator unscrew the plastic plug, and operate on the
mechanical potentiometer in order to have the pointer set to ZERO (see fig. 5). It is
possible to operate on the whole display range (± 50 µm). Replace the plastic plug.
QUICK DIGIT:
Push the RESET button to zero the indicator.
NON-MARPOSS INDICATORS
Many indicator models are available on the market, so it is difficult to determine a set-
up procedure that can meet all needs. Table 1 shows the maximum indicator
specifications with which the procedure described above can be followed.

3REPLACEMENT OF PARTS
AND COMPONENTS
10
CHAPTER 3 - REPLACEMENT OF PCHAPTER 3 - REPLACEMENT OF P
CHAPTER 3 - REPLACEMENT OF PCHAPTER 3 - REPLACEMENT OF P
CHAPTER 3 - REPLACEMENT OF PARTS AND COMPONENTSARTS AND COMPONENTS
ARTS AND COMPONENTSARTS AND COMPONENTS
ARTS AND COMPONENTS
The concept on which the bore gauge is based makes it possible to retool it via a
simple and direct replacement of some of its parts and/or components. Below all the
procedures for a correct replacement of the components are described.
3.1 PLUG GAUGE
The plug gauge is the basic element of the bore gauge, because it contains all the
movement-transduction technology. It is supplied completely assembled (see Fig. 1),
calibrated and tested at the Marposs center.
Figure 2 shows all the components that form the plug gauge and that can be replaced
in case of wear.
COMPONENTS:
1. CAP
2. CONTACTS
3. MEASURING ARMSET
4. NOSEPIECE
5. LOCKING NUT(*)
1
2
3
4
5
12
(*) A special ring nut is included for the 7,5 – 9,5 range.

11
REPLACEMENT OF PARTS
AND COMPONENTS 3
DISASSEMBLY OF PLUG GAUGE
To remove the plug gauge use the special wrenches, inserting them in the appropriate
seats (see Fig.1 and Table 1).
1. Apply wrench “A” (*) to handle seat “3” (see Fig. 2).
2. Firmly holding “A” (*), apply special wrench “B” to seat “1” and loosen the plug
gauge by turning it counterclockwise (see Fig. 3); in plug gauges for measuring
range 3 to 7.5 mm, the seat to apply the wrench “B” must be “2”.
3. Manually disassemble the plug gauge, taking care not to drop any part of it.
(*) for an INDICATOR HOLDER, use the 27mm A/F wrench;
for a PENCIL PROBE HOLDER, use the 13mm A/F wrench;
for a MINI INDICATOR HOLDER, use the 15mm A/F wrench.
3.1.1 REPLACEMENT OF PLUG GAUGE
The plug gauge can be replaced if its components are worn out, or if a retooling is
required in order to measure a different diameter.
For retooling procedures it is important to consider that the size of thread “M” for plug
gauge and handle connection, changes in relation to the measuring range of the plug
gauge (see Fig. 1 and Table 1).
1
“M”
“1”
“2”
“M”
RANGE 3-7,5 RANGE 9,5-300
RANGE 7,5-9,5
23
“A”
3
“A”
“B” 1
Ø3-5,5 5,5-7,5 7,5-9,5 9,5-26 26-300
“M”
“1”
“2”
M3,5 x 0,35 M6 x 0,75 M10 x 1
- - 6 A/F 8,5 A/F 23 A/F
3 A/F 4 A/F - 7 A/F 16 A/F
TAB. 1
“1”
“2”
“M”
“1”
“2”
ATTENTION:
The removal and/or replacement of the plug gauge may result in the loss of the zero-
setting of the bore gauge.

3REPLACEMENT OF PARTS
AND COMPONENTS
12
IMPORTANT:
The force to be applied to wrench “B” in order to lock the plug gauge depends on the size
of the latter. The table below indicates the maximum force to be applied, expressed in
newtons/meter.
45
“B”
ASSEMBLY OF PLUG GAUGE
“1”
ATTENTION:
In case of substitution of the plug gauge with one of bigger diameter, make sure that the
stem does not compress the sensor so as to reach the limit stop. This circumstance may
demage both the sensor and the plug gauge. On Fig. 6 are represented the instering distances
of the plug gauges in the handle, and the height of the thread adaptor if applied.
1. Manually screw the plug gauge in the handle seat until stopped (see Fig. 4).
2. Apply special wrench “B” to seat “1” (see Fig. 5), and lock the plug gauge to the
handle. The wrench “B” must be applied to seat “2” for plug gauges with range from
3 to 7.5 mm.
3-5,5 5,5-7,5 7,5-9,5 9,5-26
0,8 0,8 0,8 3,5
26-300
5
SUGGESTED TORQUESSUGGESTED TORQUES
SUGGESTED TORQUESSUGGESTED TORQUES
SUGGESTED TORQUES
Ø
Nw/m
range 3-5,5
range 5,5-7,5
range 7,5-9,5
range 9,5-26 range 26-300
6

13
REPLACEMENT OF PARTS
AND COMPONENTS 3
3.1.2 CAP REMOVAL
The cap is a component always supplied with the plug gauge and/or complete
application. Its function is to preserve the mechanical elements inside the plug gauge
from the penetration of coarse solid matter such as chips.
The cap can be removed in order to clean the mechanical transduction assembly and/
or to replace some components within the plug gauge.
The assembly/disassembly procedure of the cap differs according to the diameter range
of the plug gauge, as indicated below.
DISASSEMBLY OF CAP IN PLUG GAUGES FOR 12 - Ø< 120
1. Insert the bent circlip pliers in the holes “A” (see Fig. 1).
2. Tighten the pliers and extract the cap (see Fig. 2).
ASSEMBLY OF CAP IN PLUG GAUGES FOR 12 - Ø< 120
1. Take the cap and insert the bent circlip pliers in holes “A”.
2. Tighten the pliers and insert the cap in its seat within the nosepiece, as shown in
Fig. 3.
3
12
“A”
“A”

3REPLACEMENT OF PARTS
AND COMPONENTS
14
NOTE:
caps are provided for B/BC/T plug gauges with measuring range > 12 mm, and for SB plug
gauges with measuring range > 26 mm.
5
6
4
DISASSEMBLY OF CAP IN PLUG GAUGES FOR 120 - Ø< 300
1. As shown in Fig. 4, apply the 2 mm hexagonal-end wrench and unscrew the 4
screws.
2. Extract the 2 half clamps from the plug gauge.
3. Disassemble the 4 spacers by means of the 8mm A/F wrench (see Fig. 5).
ASSEMBLY OF CAP IN PLUG GAUGES FOR 120 - Ø< 300
1. Assemble the 4 spacers by means of the 8mm A/F wrench (see Fig. 5).
2. Insert the two half clamps in the plug gauge, so as to cause the holes on the half
clamps to coincide with the spacers (see Fig. 6).
3. Insert the 4 screws and screw them by means of the 2-mm hexagonal-end wrench,
so as to lock the two half clamps.

SOSTITUZIONE DELLE
PARTI EDEI COMPONENTI 3
3.1.3 CONTACTS REPLACEMENT
Marposs has developed interchangeable contacts, because these parts are subject
to wear. For their replacement, a set of special wrenches (see Table “Wrenches for
contacts”) is provided: they vary on the basis of the technical specifications of the plug
gauge. The table below indicates and represents the specifications of the contacts and
the method with which the contacts are fastened to the measuring armsets: the methods
vary in relation to the application (for through/blind bores or superblind bores) and/or to
the diameter class.
ATTENTION:
(*) The positioning of the contacts and/or extensions on the measuring armset depends
on the nominal diameter of the nosepiece, because the contact must NOT protrude more
than the maximum value expressed in the table.
(**) The values are only referred to configuration with standard clearance nosepiece/piece, for
under/over-sized configurations contact the nearest MARPOSS office, in order to get detailed
information on the application.
(***) The pipe wrenches to be applied to assembly/disassembly the contacts are in conjunction
with the application itself (through, blind, super-blind or BC), by the contacts building material
and by the diameter range of the plug gauge. In the table chart “CONTACT WRENCHES” are
expressed the wrenches according to the features mentioned above.
SUPERBLIND BORES
The contacts are an integral part of the
measuring armset, so they cannot be
disassembled.
3 - Ø< 5,5
5,5 - Ø< 7,5
THROUGH/BLIND BORES
SUPERBLIND BORES/BC
THROUGH/BLIND BORES
SUPERBLIND BORES/BC
THROUGH/BLIND BORES
SUPERBLIND BORES/BC
THROUGH/BLIND BORES
7,5 - Ø< 26
26 - Ø- 300
CONTACTS SCREWED SO AS TO TOUCH THE
MEASURING ARMSET.
CONTACTS SCREWED IN AND POSITIONED (*)
ON THE MEASURING ARMSET, AND LOCKED BY
MEANS OF ASELF-LOCKING THREAD.
CONTACTS SCREWED IN AND POSITIONED (*)
ON THE MEASURING ARMSET, AND LOCKED BY
MEANS OF ALOCK NUT.
CONTACTS SCREWED IN AND POSITIONED (*) ON
EXTENSIONS BY MEANS OF SELF-LOCKING
THREAD, WHICH IN TURN ARE SCREWED IN SO AS
TO TOUCH THE MEASURING ARMSET, BY MEANS
OF ALOCK NUT.
CONTACTS FITTED SO AS TO TOUCH THE
EXTENSIONS, WHICH ARE SCREWED IN AND
POSITIONED (*) ON THE MEASURING ARMSET, AND
LOCKED BY MEANS OF ALOCK NUT.
AA
AA
APPLICATIONPPLICATION
PPLICATIONPPLICATION
PPLICATION DD
DD
DIAMETRICALIAMETRICAL
IAMETRICALIAMETRICAL
IAMETRICAL CC
CC
C
LASSLASS
LASSLASS
LASS
(mm) FF
FF
FASTENINGASTENING
ASTENINGASTENING
ASTENING METHODMETHOD
METHODMETHOD
METHOD RR
RR
REPPRESENTATIONEPPRESENTATION
EPPRESENTATIONEPPRESENTATION
EPPRESENTATION OFOF
OFOF
OF AA
AA
A
SSEMBLYSSEMBLY
SSEMBLYSSEMBLY
SSEMBLY
RR
RR
REPRESENTATIONEPRESENTATION
EPRESENTATIONEPRESENTATION
EPRESENTATION OFOF
OFOF
OF WW
WW
WRENCHESRENCHES
RENCHESRENCHES
RENCHES
OPENOPEN
OPENOPEN
OPEN BOXBOX
BOXBOX
BOX
PP
PP
PRETRAVELRETRAVEL
RETRAVELRETRAVEL
RETRAVEL VV
VV
VALUESALUES
ALUESALUES
ALUES
(**)(**)
(**)(**)
(**)
MM
MM
MAXAX
AXAX
AX PP
PP
PROTRUSIONROTRUSION
ROTRUSIONROTRUSION
ROTRUSION OFOF
OFOF
OF
CONTACTCONTACT
CONTACTCONTACT
CONTACT
OUTOUT
OUTOUT
OUT OFOF
OFOF
OF
NOSEPIECENOSEPIECE
NOSEPIECENOSEPIECE
NOSEPIECE(*)(*)
(*)(*)
(*)
(***) See following
Technical Table See following
Technical Table
TABLE OF CONTACTSTABLE OF CONTACTS
TABLE OF CONTACTSTABLE OF CONTACTS
TABLE OF CONTACTS
_
_
_
1,6
4
3,5
For nut
For extension
For nut

3REPLACEMENT OF PARTS
AND COMPONENTS
16
(1) It consists of the measuring-armset overall travel (from the max opening position to the internal stop)
(2) Difference between the contacts max opening position and the nosepiece minimum diameter.
NoteNote
NoteNote
Note: Each contact can be calibrated with a different pretravel value, provided that the “Minimum Pretravel”
reported on the table is applied and the sum of the two pretravels don’t exceed the expressed value on
Standard Pretravel (considering also the reported tolerances)
(3) Maximum pretravel adjustment margin, as indicated on point (2)
(4) Tolerance range of the piece to be measured by the plug-gauge.
(5) Maximum measurable range of the plug-gauge, considering the contacts coupling and an adjustable pretravel
as expressed on point (3)
(6) Plug-gauge measuring force for each contact, measured at bottom end of the working range in compression
stage; without pencil probe or dial indicator.
Note: When a pencil probe or dial indicator is associated to the plug-gauge, it is necessary to add to the
measuring force F at zero per contact (as indicated in the table), the force of the probe or indicator (Ft)
multiplied by a coefficient of 1,34 (from 7,5 to 26 mm), or 1,2 (from 3 to 7,5mm and from 26 mm to end
range).
F with probe or indicator = F + ( Ft * 1,34 ) (plug-gauges 7,5-26mm)
F with probe or indicator = F+(Ft* 1,2) (plug-gauges 3-7,5mm and 26-300mm)
To decrease the measuring force it is possible to remove the spring from the plug-gauge, or to apply
low-pressure pencil probes or dial indicators.
(7) Meaning with "range" the range of values where the MBG is actually gauging, within the application range.
For instance: within a range of 100 µm, the plug-gauge accuracy error will be (1+1) µm= 2 µm. exagonal "U-shape"
Pipe Wrench Open wrenches
CONTACT WRENCH TABLE
1346041100
1346041101
1346041102
1346041103
1346041104
1346041106
1346041107
1346040025
1346040021
26 ≤ø<300
20 ≤ø<300
16 ≤ø<300
26 ≤ø<300
26 ≤ø<300
9,5 ≤ø<26
7,5 ≤ø<26
16 ≤ø<20
7,5 ≤ø<9,5
7,5 ≤ø<16
5,5 ≤ø<7,5
7,5 ≤ø <26
7,5 ≤ø<26
26 ≤ø<300
4 mm “U” pipe wrench
3,8 mm hexagonal pipe
wrench
3,5 mm hexagonal pipe
wrench
3,1 mm hexagonal pipe
wrench
2,5 mm hexagonal pipe
wrench
1,5 mm hexagonal pipe
wrench
1,5 mm “U” pipe wrench
1,6mm A/F open wrench
4mm A/F open wrench
DESCRIPTION ORDER CODE
Tungsten Carbide and DLC
Diamond
Diamond
Contacts Extensions
Tungsten Carbide and DLC
Tungsten Carbide and DLC
Tungsten Carbide and DLC
with 2,5 mm radius
Diamante
Tungsten Carbide and DLC
with 1,5 mm radius
Diamond
Tungsten Carbide
Tungsten Carbide
Lock nut contacts of
Tungsten Carbide and DLC
Lock nut contacts of
extension
CONTACTS TYPE APPLICATION
SB
B
T
SB
B/BC/T
B/BC/T
T
B
B/BC/T
B/T
B/BC/T
SB
SB
T/B/BC/SB
RANGE
(mm)
-10 ÷ +65
TECHNICAL TTECHNICAL T
TECHNICAL TTECHNICAL T
TECHNICAL TABLEABLE
ABLEABLE
ABLE
DD
DD
DESCRIPTIONESCRIPTION
ESCRIPTIONESCRIPTION
ESCRIPTION
DD
DD
DIAMETRICALIAMETRICAL
IAMETRICALIAMETRICAL
IAMETRICAL RR
RR
RANGEANGE
ANGEANGE
ANGE
MBG-T/B
MBG-SB/BC
RANGE(1)
ø 3 ÷ 4
mm
ø 4 ÷ 5,5
mm
0,31÷0,4
STANDARD
PRETRAVEL(2)
0,250
00
00
0
+0,05+0,05
+0,05+0,05
+0,05
M AX . A PPLICATION RANGE
(5)
UU UU
UNITNIT
NITNIT
NIT
ø 5,5 ÷ 7,5
mm
ø 7,5 ÷ 9,5
mm ø 26
÷ 60
mm
ø 60 ÷ 150
mm
ø 150÷200
mm
ø 200÷300
mm
ø 9,5 ÷ 26
mm
mm
0,34÷0,45 0,36÷0,7 0,37÷0,7
0,37÷1,2
0,55÷1,05
0,55÷1,2 1÷1,5 1÷1,5 1÷1,5 1÷1,5
MBG-T/B
MBG-SB/BC
mm
0,280
00
00
0
+0,05+0,05
+0,05+0,05
+0,05
0,300
00
00
0
+0,05+0,05
+0,05+0,05
+0,05
0,300
00
00
0
+0,05+0,05
+0,05+0,05
+0,05
0,350
00
00
0
+0,05+0,05
+0,05+0,05
+0,05
0,500
00
00
0
+0,05+0,05
+0,05+0,05
+0,05
0,700
00
00
0
+0,05+0,05
+0,05+0,05
+0,05
0,800
00
00
0
+0,05+0,05
+0,05+0,05
+0,05
0,900
00
00
0
+0,05+0,05
+0,05+0,05
+0,05
0,520
00
00
0
+0,05+0,05
+0,05+0,05
+0,05
0,580
00
00
0
+0,04+0,04
+0,04+0,04
+0,04
0,580
00
00
0
+0,04+0,04
+0,04+0,04
+0,04
MBG-T/B
MBG-SB/BC
MIN PRETRAVEL
FOR EACH
CONTAC
mm
0,125 0,140 0,150 0,150 0,175 0,250 0,350
0,260
0,400
0,290
0,450
0,290
ADJUSTABLE
PRETRAVEL(3)
MBG-T/B
MBG-SB/BC
mm
APPLICATION
RANGE(4)
MBG-T/B
MBG-SB/BC
mm
no
0,100
no
0,120
no
0,120
up to 0,35
0,120
up to 0,5
0,120 0,150 0,150
0,120
0,150
0,08
0,150
0,08
up to 0,8
up to 0,65
up to 0,8
up to 0,65
up to 0,95
up to 0,65
up to 0,95
up to 0,65
mm
no no no 0,170 0,220 0,320 0,320 0,320 0,320
MEASURING FORCE(6)
N
-1 µm
ACCURA-
CY
RANGE (0÷100)µm
(7)
RANGE (>100)µ m
(7)
%
1% measuring range +1µm
2% measuring range +1µm
OPERATING TEMPERATURE
THERMAL
DRIFTOF
ZERO
3-ø<80
80-ø<150
150-ø-300
µm/°C
°C
-0,15
-0,2
-0,25
-0,3
m
REPEATABILITY (2,77σ)
0,1 - 0,5 0,1 - 0,5 0,1 - 0,5 0,1 - 0,5 0,1 - 0,6 0,4 - 1,35 0,4 - 1,35 0,4 - 1,35 0,4 - 1,35
ø 25 ÷ 300 mm
ø 3 ÷ 5,5 mm
0,200
00
00
0
+0,05+0,05
+0,05+0,05
+0,05
0,200
00
00
0
+0,05+0,05
+0,05+0,05
+0,05
0,100 0,100
0,007 0,007

17
REPLACEMENT OF PARTS
AND COMPONENTS 3
DISASSEMBLY OF CONTACTS
1. Unscrew the contact and disassemble it, using the appropriate wrench (see Table
of Contacts).
ASSEMBLY AND POSITIONING OF CONTACTS
The positioning of the contact depends on the type of measuring armset that is being
used (see Table of contacts). There are basically two types of contacts:
••
••
• those that are screwed to the fingers so as to touch them;
• those that are screwed to the fingers but require a position adjustment, because there
is no mechanical reference.
Below there is a description of the procedure, in relation to the indicator that is being
used.
DIAMETER ADJUSTMENT OF CONTACTS WITH PENCIL PROBES AND TD1, TD10 AND
QUICK DIGIT INDICATORS
1. If not assembled, insert and lock the indicator to the bore gauge, at a depth that
ensures a view of the entire bore gauge pretravel (see Table of contacts).
2. Screw in contacts “T1” and “T2” by means of the relevant wrench (see CONTACTS
WRENCH TABLE), so as to fit them inside nosepiece “A” (see Fig. 1).
3. With the bore gauge in vertical position, unscrew contact “T1” so as to protrude it
out of the nosepiece (see Fig. 2) by an amount that ensures that, when the plug
gauge is inserted in the master and pressed against it on the side of contact “T1”,
the display shows a shift equal to 50% of the application range as specified on the
TECHNICAL TABLE.
4. Unscrew the contact “T2” so as to protrude it out of the nosepiece by
approximately 50% of the application range; inserting the plug gauge in the
master, the display must shows a value next to the application range (see Fig. 3).
5. With the plug gauge inserted in the master, carry out the fine zero-setting procedu-
re of the display device.
12
3
T2
A
T1
C/2
C/2 C/2
T1
NOTE:
make sure to have an equal protrusion of the two contacts outside of the nosepiece.

3REPLACEMENT OF PARTS
AND COMPONENTS
18
DIAMETER ADJUSTMENT OF TD1P INDICATOR
1. Insert and lock the indicator in the indicator holder by means of the 2 mm hexagonal-
end wrench (see Fig. 4) at a 7 mm “A” dimension.
2. Loosen the ring nut “1” by means of a 16mm A/F or with a 2mm hexagonal wrench
(see Fig. 5). Turn the handle clockwise so as to visualize zero on the display (see
Fig. 6).
3. Manually lock ring nut “1” so as to obtain a friction movement of the indicator holder.
4. Screw the contacts by means of the relevant wrench (see CONTACTS TABLE), in
order to bring them inside the nosepiece (see Fig. 1).
5. Unscrew the contact “T1” and, inserting the plug gauge in the master, check for a
shift of + 50 µm on the display (see Fig. 7).
6. Firmly holding the indicator turn the handle clockwise until – 50 µm is visualized by
the display (see Fig. 8).
7. Repeatedly extract and insert the bore gauge in the master unscrewing contact
“T2” each time, until the value ZERO is displayed.
In this way the excursion for each contact is 50 µm (equal to a 100 µm application
range). If the application range defined on the TECHNICAL TABLE has not been
reached, repeat steps 5 – 6 – 7 until its achievement.
8. Unscrew the plastic plug from the upper part of the indicator, and set the indicator
pointer to ZERO by means of the mechanical potentiometer (see Fig. 9). It is possible
to operate on the whole display range (± 50 µm).
Replace the plastic plug.
78
456
NOTE:
make sure to have an equal protrusion of the two contacts outside of the nosepiece.
“A”
9

19
REPLACEMENT OF PARTS
AND COMPONENTS 3
3.1.4 DISASSEMBLY OF NOSEPIECE/ARMSET
NOSEPIECE:NOSEPIECE:
NOSEPIECE:NOSEPIECE:
NOSEPIECE:
The nosepiece (see Fig. 1) is the guiding element that makes the measurement
independent from the operator’s manual skill. Despite its considerable hardness, it is
subject to wear, therefore it can be removed and replaced with a new or reconditioned
one.
MEASURING ARMSETMEASURING ARMSET
MEASURING ARMSETMEASURING ARMSET
MEASURING ARMSET
The measuring armset is the bore gauge measuring element, transducing the mechanical
movement of the contacts for the display device. The versions developed are basically
2: one with FINGERS (measuring range from ≥3 mm to < 26 mm), and one with
PARALLELOGRAM (measuring range, from ≥26 mm to ≤300 mm). Fig. 2 shows the
models in relation to their measuring range. Fig. 3 shows, as example, the measuring
armset composition for a range between 9,5 and 26.
A. Armset
B. Rod
C. Spring
D. Sliding bushing
E. Nosepiece locking nut
NOTE:
It is possible to perform the retooling of the bore gauge by replacing the nosepiece and
contacts (unless the latter cannot be repositioned), provided that the nominal diameter of
the nosepiece is compatible with the measuring range of the measuring armset (see Fig. 2).
3
1
2
3-Ø<5,5 5,5-Ø<7,5 7,5-Ø<9,5 9,5-Ø<26 26-Ø<300
B
A
C
D
E
ARMSETS PARALLELO-
GRAM

3REPLACEMENT OF PARTS
AND COMPONENTS
20
DISASSEMBLY/ASSEMBLY OF NOSEPIECE/MEASURING ARMSET FOR
RANGE 3 - 5,5 mm
Due to the reduced dimensions of the components the interchangeability is
not possible.
DISASSEMBLY/ASSEMBLY OF NOSEPIECE/MEASURING ARMSET FOR
RANGE 5,5 - 26 mm
Special tools are required to disassemble and assemble these components, in order
to ensure the proper nosepiece/measuring armset coupling. Due to this reason it is
strongly recommended to contact the nearest MARPOSS office.