Guitar Bridge FMEA
From DDL Wiki
(Difference between revisions)
Jozer99 (Talk | contribs)
(New page: ==== Fender Failure Mode Analysis ==== {| class="wikitable" border="1" |- align="center" ! Item & Function !! Failure Mode !! Effects of Failure !! S !! Causes of Failure !! P !! Design...)
Newer edit →
Current revision
Fender Failure Mode Analysis
Item & Function | Failure Mode | Effects of Failure | S | Causes of Failure | P | Design Controls | D | RPN | Recommended Actions |
---|---|---|---|---|---|---|---|---|---|
G1 Back Panel Cover Screw
| Screw holes may become stripped with frequent removal | Back panel no longer secure, lack of panel could cause harm to bridge internals or user | 4 | Screw holes become stripped | 4 | Test number of screw/unscrew cycles before failure on test guitars | 1 | 16 | Use metal inserts, or a latch system instead of wood screws on higher end guitars |
G2 Back Panel Cover
| Back panel may break when large amounts of pressure are put on it | Without back panel, the bridge mechanism can become fouled on user's clothing, may pinch user | 4 | Plastic plate cracks | 1 | Test force necessary to break back pannel | 2 | 8 | Use stronger plastic back plate, or a plastic/metal plate |
G4 Springs
| When springs removed for servicing, may shoot off | Harm to guitar, or user | 9 | Springs not adequately anchored | 3 | Measure spring tension at factory | 3 | 81 | Design springs to be easily removable, or create anchor cable to prevent spring from flying away (like a garage door spring cable) |
G5 Whammy Bar
| Shear failure at base | Broken handle, leading to an inability to use tremolo function without replacement. | 7 | Bar not strong enough near base | 2 | Test for imperfections using x-ray | 7 | 98 | Design bar to be thicker at base, where forces are greatest |
Hard to tell if bar is inserted correctly | 3 | None (design flaw) | 1 | 21 | Design bar so it is difficult to insert incorrectly | ||||
G6 Bridge Mounting Screws
| With excessive use, the screws may become lose | Lose bridge, resulting in tuning problems | 3 | Bridge screws not tight | 4 | Measure screw tightness at factory | 2 | 24 | Use special screws designed not to work lose with operation of the bridge |
Floyd Rose Failure Mode Analysis
Item & Function | Failure Mode | Effects of Failure | S | Causes of Failure | P | Design Controls | D | RPN | Recommended Actions |
---|---|---|---|---|---|---|---|---|---|
FR1 Whammy Bar
| Shear failure at base | Broken handle, leading to an inability to use tremolo function without replacement. | 7 | Bar not strong enough near base | 2 | Test for imperfections using x-ray | 7 | 98 | Design bar to be thicker at base, where forces are greatest |
Hard to tell if bar is inserted correctly | 3 | None (design flaw) | 1 | 21 | Design bar so it is difficult to insert incorrectly | ||||
FR2 Springs
| When springs removed for servicing, may shoot off | Harm to guitar, or user | 9 | Springs not adequately anchored | 3 | Measure spring tension at factory | 3 | 81 | Design springs to be easily removable, or create anchor cable to prevent spring from flying away (like a garage door spring cable) |
FR8 Clamp Screw
| Screw head becomes worn | Becomes impossible to unscrew screws, or change strings | 3 | Screw metal too soft | 3 | Measure screw hardness at factor | 2 | 18 | Use stronger metal for screws, or use screw head type more resistant to wear (Torx) |
FR11 Tuner Spring
| Spring bent when user services guitar | Spring provides inadequate pressure on tuners | 6 | Spring too easy to access | 3 | None (design flaw) | 1 | 18 |
|
Spring too weak | 3 | None (design flaw) | 1 | 18 | Redesign spring to be thicker stamped piece | ||||
FR12 Baseplate
| "Knife Edges" become dull with use | Friction at pivot point increases, bridge ceases to return to pitch correctly. | 5 | Knife Edges not hard enough | 1 | Batch test knife edges for hardness | 3 | 15 | Use higher grade steel for knife edges |
Too much pressure on knife edges | 8 | Design flaw, need pivot mechanism with larger contact area to spread pressure | 1 | 40 | Redesign pivot mechanism |