Dynabrade 50727 User manual

Always operate, inspect and maintain this tool in accordance with the Safety Code for portable air tools
(ANSI B186.1) and any other applicable safety codes and regulations. Please refer to Dynabrade’s
Warning/Safety Operating Instructions for more complete safety information.
Air Motor and Machine Parts
Parts Page Reorder No. PD00•15
Effective February, 2000
Supercedes PD97•17
.4 Hp/Right-Angle/Rear Exhaust
2" Depressed Center Wheel Grinder
Index Key
No. Part Description
150041 GuardAssembly
1A50081 Wheel Flange
250083 Spacer
302028 Spindle
402035 Lock Nut
501486 Felt Silencer
654520 Bearing
797116 Shim
897117 Shim
997118 Shim
10 02623 Gear - 12,000 RPM
02597 Gear - 15,000 RPM
02599 Gear - 20,000 RPM
11 02042 Wick - 12,000 RPM
02044 Wick - 15 & 20,000 RPM
12 02043 Wick - 12,000 RPM
02045 Wick - 15 & 20,000 RPM
13 02031 Housing – Includes:
13A01041 Gear Oil Fitting
13B02041 Gear Oil Plate
13C02033 Needle Bearing
14 02624 Pinion - 12,000 RPM
02598 Pinion - 15,000 RPM
02600 Pinion - 20,000 RPM
15 01461 Lock Nut
16 02697 Bearing
17 54543 Shim
18 54544 Shim
19 54551 Shim
20 01478 Bearing Plate
21 50767 Pin (2)
22 01479 Spacer
23 02037 Rotor
24 01480 Blade (4/pkg.)
25 01476 Cylinder
26 02676 Bearing Plate
27 02696 Bearing
28 02679 Shield
29 01547 Collar
30 02066 Housing - 50727
02067 Housing - 50728
02068 Housing - 50729
31 12132 Pin
32 01449 Valve Stem
33 01448 Throttle Lever
34 01464 Seal
35 01472 Tip Valve
36 01468 Spring
37 01564 Spacer
38 95558 Retaining Ring
39 95730 O-Ring
40 01469 Speed RegulatorAssy.
41 01024 O-Ring
42 95438 O-Ring
43 95711 Retaining Ring
44 94521 Muffler Base
45 94528 Felt Muffler
46 94522 Muffler Cap
47 95375 O-Ring
48 94526 Spacer
49 94523 InletAdapter
50 94519 MufflerAssembly
WARNING
!
Models:
50727 – 12,000 RPM
50728 – 15,000 RPM
50729 – 20,000 RPM
A8
O1
3
5
7
9
4
6
8
11
10
12
14
15 16 17 18 19
20
21
22
23
25
24
21 26
27
28
29
30
31
33
32
34 36
35 37
38
40
39
41
A8
A4
W1
W1
13
13C
13B
13A
17 N•m
T
34 N•m
T
For Serial No. 0B1000 and Higher
23 N•m
T
23 N•m
TO1
2
1
1A
45
46
47 48
49
44
43
42
50
Loctite: A4= Loctite #680
A8= Loctite #567
Torque: N•m x 8.85 = In. - lbs.
Oil: O1=Air Lube
WWicking: W1= Gear Oil
O
A
T
KEY
A8
Left Hand Threads
Right Hand Threads
Buy parts on line at https://Dynashop.co.uk/ for all things Dynabrade
Buy parts on line at https://Dynashop.co.uk/ for all things Dynabrade

2
Model Length Height Weight Spindle Air Flow Rate Sound Motor Motor
Number Inch (mm) Inch (mm) Pound (kg) Thread SCFM (LPM) Level HP (W) RPM
All Models 7-5/16" (186) 2-7/8" (71) 1.22 lbs. (.54) 3/8" -24 male 21 (595) 84-86 dBA .43 (321) 12,000-20,000
Additional specifications: Air Inlet Thread 1/4" NPT • Hose Size 3/8" (9 mm) • Air Pressure 90 PSI (6.2 Bars)
Warning: Eye, face, respiratory, sound, and body protection must be worn while operating power tools. Failure to do so may result in serious injury or death.
Follow safety procedures posted in workplace.
1. With power source disconnected from tool, securely fasten abrasive/accessory on tool.
2. Install air fitting into inlet bushing of tool. Important: Secure inlet bushing of tool with a wrench before attempting to install the air fitting to avoid
damaging valve body housing.
3. Connect power source to tool. Be careful not to depress throttle lever in the process.
4. Check tool speed with tachometer. If tool is operating at a higher speed than the RPM marked on the tool or operating improperly, the tool should be
serviced to correct the cause before use.
Maintenance Instructions:
1. Check tool speed regularly with a tachometer. If tool is operating at a higher speed than the RPM marked on the tool, the tool should be serviced to
correct the cause before use.
2. Some silencers on air tools may clog with use. Clean and replace as required.
3. All Dynabrade air motors should be lubricated. Dynabrade recommends one drop of air lube per minute for each 10 SCFM (example : if the tool
specification state 40 SCFM, set the drip rate of your filter-lubricator at 4 drops per minute). DynabradeAir Lube (P/N 95842: 1pt. 473ml.) is
recommended.
4. An air line filter-regulator-lubricator must be used with this air tool to maintain all warranties. Dynabrade recommends the following: 11405 Air Line Filter-
Regulator-Lubricator — Provides accurate air pressure regulation, two-stage filtration of water contaminants and micro-mist lubrication of pneumatic
components. Operates up to 40 SCFM @ 100 PSI has 3/8" NPT female ports.
5. Lubricate wick system through angle gear head Gear Oil fitting with 2-3 drops every 8 hours of use for maximum gear life. Important: Use recommended
angle gear oil only for wick system. Do not contaminate wick with any other oil or grease product (Order 95848 Gear Oil and 95541 Gun).
6. Use only genuine Dynabrade replacement parts. To reorder replacement parts, specify the Model #, Serial # and RPM of your machine.
7. Amotor tune-up kit (P/N 96179) is available which includes assorted parts to help maintain motor in peek operating condition. Please refer to
Dynabrade’s Preventative Maintenance Schedule for a guide to expectant life of component parts.
8. Mineral spirits are recommended when cleaning the tool and parts. Do not clean tool or parts with any solvents or oils containing acids, esters, keytones,
chlorinated hydrocarbons or nitro carbons.
Important Operating, Maintenance and Safety Instructions
Carefully read all instructions before operating or servicing any Dynabrade®Abrasive PowerTool.
Warning: Hand, wrist and arm injury may result from repetitive work motion and overexposure to vibration.
Important: All Dynabrade air tools must be used with a Filter-Regulator-Lubricator to maintain all warranties.
•Important: User of tool is responsible for following accepted safety codes such as those published by theAmerican National Standards Institute (ANSI).
•Operate machine for one minute before application to workpiece to determine if machine is working properly and safely before work begins.
•Always disconnect power supply before changing abrasive/accessory or making machine adjustments.
•Inspect abrasives/accessories for damage or defects prior to installation on tools.
•Please refer to Dynabrade’s Warning/Safety Operating Instructions Tag (Reorder No. 95903) for more complete safety information.
•Warning: Hand, wrist and arm injury may result from repetitive work, motion and overexposure to vibration.
Notice
All Dynabrade motors use the highest quality parts and metals available and are machined to exacting tolerances. The failure of quality pneumatic motors can
most often be traced to an unclean air supply or the lack of lubrication. Air pressure easily forces dirt or water contained in the air supply into motor bearings
causing early failure. It often scores the cylinder walls and the rotor blades resulting in limited efficiency and power. Our warranty obligation is contingent upon
proper use of our tools and cannot apply to equipment which has been subjected to misuse such as unclean air, wet air or a lack of lubrication during the use of
this tool.
Operating Instructions:
Safety Instructions:
Products offered by Dynabrade should not be converted or otherwise altered
from original design without expressed written consent from Dynabrade, Inc.
OneYearWarranty
Following the reasonable assumption that any inherent defect which might prevail in a product will become apparent to the user within one year from the date
of purchase, all equipment of our manufacture is warranted against defects in workmanship and materials under normal use and service. We shall repair or
replace at our factory, any equipment or part thereof which shall, within one year after delivery to the original purchaser, indicate upon our examination to
have been defective. Our obligation is contingent upon proper use of Dynabrade tools in accordance with factory recommendations, instructions and safety
practices. It shall not apply to equipment which has been subject to misuse, negligence, accident or tampering in any way so as to affect its normal
performance. Normally wearable parts such as bearings, contact wheels, rotor blades, etc., are not covered under this warranty.
Buy parts on line at https://Dynashop.co.uk/ for all things Dynabrade
Buy parts on line at https://Dynashop.co.uk/ for all things Dynabrade

Disassembly/Assembly Instructions - Right-AngleTools
Important: Manufacturer’s warranty is void if tool is disassembled before warranty expires.
Please refer to parts breakdown for part identification.
Gear Casing Disassembly:
Important: inlet adapter must be secured before attempting to remove air fitting to avoid damaging composite motor housing.
1. Secure motor housing in vise using 52296 Repair Collar or padded jaws, so that 02031 Right-Angle Head Housing is facing up.
2. Using an adjustable pin wrench turn 02035 Lock Nut counter-clockwise.
3. Remove spindle from 02031 Housing.
4. Using a screw driver, pick wicks (2) out from housing (Note: wick may already be removed with the spindle).
5. Using a 34.0 mm crows foot wrench, remove 01461 Lock Nut by turning counter-clockwise.
6. Place 02031 Housing in an arbor press with spindle opening facing down.
7. Using a 9.0 mm drift pin press out 02041 Gear Oil Plate and 02033 Bearing (located on the top of the 02031 Housing).
Motor Disassembly:
1. Remove tool from vise.
2. Pull motor assembly from housing assembly.
3. Disassemble motor assembly by pressing 02037 Rotor from 02696 Rear Bearing. Press 02696 Bearing out of 02676 Rear Bearing Plate.
4. Remove 01476 Cylinder and 01480 Blades.
5. Place 02037 Rotor in a vise with soft jaws and unscrew pinion using a counter-clockwise direction.
6. Slip 01478 Front Bearing Plate off of 02037 Rotor.
7. Remove 01479 Spacer from 02037 Rotor.
8. Remove 02697 Bearing from 01478 Front Bearing Plate.
9. Remove shims from 01478 Front Bearing Plate.
Valve Body Disassembly:
1. Secure motor housing in 52296 Repair Collar or padded jaws with motor opening facing down.
2. Unscrew inlet adapter turning counter-clockwise.
3. Using needle nose pliers, remove 01468 Spring, 01472 Tip Valve, and 01464 Seal.
4. Resecure housing in vise making sure throttle lever 01448 Throttle Lever and 12132 Pin are accessible.
5. Using a 2.5mm diameter drift pin and hammer, tap 12132 Pin until it falls out of the housing and remove throttle lever.
6. Remove from vise.
7. Remove 95558 Retaining Ring using retaining ring pliers.
8. Push 01469 Speed Regulator from housing.
Gear Casing Reassembly:
1. Press 01041 Gear Oil Fitting into 02041 Gear Oil Plate with 01041 Gear Oil Fitting Head
recessed into 02041 Gear Oil Plate.
2. Place 2 drops of #680 Loctite®(or equivalent) at location below.
3. Place 02041 Gear Oil Plate into 02031 Housing as shown.
4. Press 02033 Needle Bearing into 02031 Housing as shown.
Motor Reassembly:
Important: Make sure parts have been cleaned and thoroughly inspected for wear and
damage before reassembly.
1. Place 02037 Rotor in soft jaw vise with threaded spindle facing upward.
2. Slip 01479 Spacer onto 02037 Rotor.
3. Place a .002” Shim into 01478 Front Bearing Plate as an initial spacing then slip 02697 Bearing into 01478 Front bearing Plate. Slip assembly onto
02037 Rotor. Tighten pinion onto rotor torque 17 N•m, 150 in.-lbs.
4. Check clearance between rotor and bearing plate by using a .001" feeler gauge. Clearance should be at .001" to .0015". Adjust clearance by repeating
steps 1-3 with different shim if necessary.
5. Once proper rotor gap clearance is achieved, install well lubricated 01480 Blades into 02037 Rotor (use 95842 DynabradeAIr Lube or equivalent).
6. Install 01476 Cylinder so it rests against the 01478 Bearing Plate (making sure inlet holes of cylinder are in alignment with inlet holes in 02676 Rear
Bearing Plate).
7. Press 02696 Bearing into 02676 Rear Bearing Plate. Press these parts onto 02037 Rotor. Important: Fit must be snug between bearing plates and
cylinder. If too tight, rotor will not turn freely. Rotor must then be lightly tapped at press fit end so it will turn freely while still maintaining a snug fit. A
loose fit will not achieve the proper preload of motor bearings.
8. Secure housing in vise using 52296 Repair Collar or padded jaws so that motor cavity faces upward.
9. Install motor assembly in housing, make sure motor drops all the way into housing. (Note: Align the nodes in side of housing).
10. Slip 01547 Insulator Collar over 01461 Lock Nut.
11. Apply Loctite®#567 to threads, and screw 01461 Lock Nut (left-hand threads), onto 02031 Housing.
12. Thread 02031 Housing and 01461 Lock NutAssembly onto motor housing assembly (right-hand threads), drawing the two assemblies together.
13. Adjust orientation of throttle lever to agree with your grip and comfort level allowing for additional rotation due to tightening to set torque.
(continued on next page)
3
02031 Housing 02033 Needle Bearing
02041 Gear Oil Plate
2 Drops of Loctite
01041 Gear Oil Fitting
Buy parts on line at https://Dynashop.co.uk/ for all things Dynabrade
Buy parts on line at https://Dynashop.co.uk/ for all things Dynabrade

Disassembly/Assembly Instructions - (continued)
14. Using a 34.0 mm crow foot and a torque wrench set at (34 N•M/300 in. - lbs.), secure the gear case housing and lock nut in place.
15. Press 54520 Bearing and then gear onto spindle shaft, making sure drive hexes are aligned.
16. Place 01486 Silencer over spindle shaft at threaded end.
17. Slip bottom wick over spindle shaft, then place top wick over spindle shaft.
18. Insert spindle shaft assembly into 02031 Housing.
19. Torque 02035 Lock Nut to 23 N•m, 200 in. - lbs
20. Shim spindle assembly using shims if required.
Note: When assembling angle-head assembly onto the motor housing, make sure flats on the wicks are both facing the pinion or tool will not run.
Tool Assembly is complete. Please allow 30 minutes for adhesives to cure before operating tool.
Important: Before operating, place 2-3 drops of Dynabrade Air Lube (P/N 95842) directly into air inlet with throttle lever depressed. Operate tool for
30 seconds to determine if tool is operating properly and to allow lubricating oils to properly penetrate motor. Motor should now be tested for proper operation at
90 PSI. If motor does not operate properly or operates at a higher RPM than marked on the tool, the tool should be serviced to correct the cause before use.
Loctite®is a registered trademark of Loctite Corp.
DYNABRADE®
DYNABRADE, INC., 8989 Sheridan Drive •Clarence, NY 14031-1490 •Phone: [phone] •Fax: [phone] •International Fax: [phone]
DYNABRADE EUROPE S.àr.l., ZoneArtisanale •L-5485 Wormeldange—Haut, Luxembourg •Telephone: [phone] •Fax: [phone]
©DYNABRADE, INC., 2000 PRINTED IN USA
Visit our Web Site: www.Dynabrade.com Email: Customer[email protected]
Accessories
96179 Motor Tune-Up Kit
•Includes assorted parts to help
maintain motor in tip-top shape.
DynabradeAngle Gear Oil
•Specifically formulated to saturate wick system in right
angle gear head.
•95848: 2 oz. tube
•95849: 10 oz. tube
52296 Repair Collar
•Specially designed collar for use in vise to prevent damage
to valve body of tool during disassembly/assembly
Dynaswivel®
•Swivels 360° at two locations which allows an
air hose to drop straight to the floor, no matter
how the tool is held.
•94300 1/4" NPT
Buy parts on line at https://Dynashop.co.uk/ for all things Dynabrade
Buy parts on line at https://Dynashop.co.uk/ for all things Dynabrade