Bach Trumpet & Trombone Bell Thickness Stamps
Vincent Bach’s trumpets and trombones used different brass thicknesses (and suppliers) through various manufacturing eras of the Vincent Bach Corporation brands.
The list below includes details from the New York manufacturing era (pre-1953).
Note:
Modern Bach Stradivarius 180-series trumpets manufactured in Elkhart use a thicker standard bell brass thickness of 0.025″ and 0.020″ for lightweight bells combined with a bell manufacturing forming process for a more consistent bell thickness after forming.
Trumpet Bell Thickness Stamps
For a limited period (~ 1930s) during the New York era, the bell brass thickness marking was stamped on the bell. The stamp number indicated the thickness of the brass used. For example, a 45 stamp = 0.45mm or 0.018-inch brass thickness is used to manufacture the bell.
Bell thickness stamps were used through the 1930s, but discontinued as Vincent Bach Corporation started to standardize the bell thickness across more standard Bach Trumpets.
The first known examples start in the late 1920s/early 1930, and the last known bell with a thickness stamp stops around 1937 – 1938.
Serial Number # | Bell Model Stamp | Mfg. Year | Thickness Stamp | |
|---|---|---|---|---|
706 | Rotary, Bb | none | 1926 | None |
1615 | Trumpet, C | 213 | 1930 | "40" |
2019 | Trumpet, Bb | 7-10-62 | 1933 | "45" |
2552 | Trumpet, Bb | 7-10-62 | 1934 | "45" |
2659 | Trumpet, Bb | 26-59 | 1935 | "45" |
2761 | Trumpet, Bb | 7-10-62 | 1935 | "45" |
2951 | Cornet, Bb | 25-62 | 1935 | "45" |
3458 | Trumpet, Bb | none | 1937 | none |
4077 | Trumpet, Bb | 7-59 | 1937 | "51" |
Various ("67" Bronx) | Trumpet Cornet etc. | 1943 | None |
Trumpet Bell Thicknesses
After World War II, Vincent Bach had standardized his bell thickness, and the following tables are from Vincent Bach’s notebooks from 1951, before he relocated his factory to Mt. Vernon in 1953.
Model | Bb | Bb | C | C |
|---|---|---|---|---|
Bell Mandrel | various | various | #211 | #228, #238 |
Thickness | 0.018" | 0.019" | 0.018" | 0.018" |
Bell Diameter | 4 7/8" | 4 7/8" | 4 3/4" | 4 7/8" |
Equivalent Bell Stamp | 45 | 48 | 46 | 46 |
Instrument | Bb | C (SM) | C (ML/L) | D / Eb | F / G | Bb High |
|---|---|---|---|---|---|---|
Bell Thickness | 0.019 | 0.018 | 0.018 | 0.017 (D) 0.016 (Eb) | 0.015 (F) 0.016 (G) | 0.014 |
Bell Diameter | 4 7/8" 124mm | 4 3/4" 121mm | 4 7/8" 124mm | 4 9/16" 116mm | 4 1/4" (F) 108mm (F) 4 1/8" (G) 106mm (G) | 4" 102mm |
Equivalent Stamp | 48 | 46 | 46 | 43 (D) 41 (Eb) | 38 (F &G) | 36 |
Trombone Bell Thicknesses
Model - Trombone | Alto | Tenor | Tenor | Bass |
|---|---|---|---|---|
Thickness | 0.019" | 0.021" | 0.021" | 0.022" |
Bell Diameter | 6 1/2" | 7" 7 1/2" | 8" | 9" 9 1/2" |
Equivalent Bell Stamp | 48 | 52 | 52 | 56 |
source: BachLoyalist research
