Author: Chris P
Date: 2007-08-06 23:14
Here's a venting guide - check with feeler gauges made from sheet brass or plastic with tips of 1mm, 1.5mm, 2mm, 2.5mm and 3mm to check the opening at the front of the pads (furthest away from the hinge):
Top Joint:
2nd 8ve - between 1-1.5mm - see below.
1st 8ve - adjust the screw so the 2nd 8ve opens between 1-1.5mm.
3rd 8ve - very little, but only just opening and check the altissimo speaks.
trills - 1mm.
LH 1 fingerplate - very little, check the upper D and alt. C#.
C vent - 2mm.
All other pads once regulated should have the correct venting if the C pad opens by 2mm (sand the cork under LH 2 key foot anf under the side G#-A trill lever to open up the venting, or replace the corks if there's too much venting). The Ab-Bb link from the G# key should have enough play in it so the G# pad opens as much as possible, but the side G#-A trill key (the one that overlaps the side G# key) should be able to close the LH 2 fingerplate as well as LH 3 - though it's not important that it closes LH 2 fully. It still has to close LH 3 otherwise the G#-A trill won't be in tune using the side key.
Lower joint:
RH 1 - should have a fair amount of venting, determined by how much it opens the top joint Bb and C pads by, and also a tiny amount of double action before it lifts the linkage (con bar) to be sure the Bb and C pads are fully closing, and after to be sure RH 1 closes.
F# vent - 2mm.
RH 2 and RH 3 - determined by the venting of the F# vent. Adjust RH 3 with the adjusting screw that operates the F vent rocker, and RH 2 by sanding the cork on the foot that also closes the F vent.
Low C and B - 3mm max. If more venting needed on the low C, adjust by carefully bending the wire that connects with the underside of the C# touch. if the low B needs more venting, either sand the cork on the RH low B key foot (the part that operates the low B key) or carefully bend the low B key upwards to get more opening, and adjust the C# screw so it closes with the low B. On closing the C key, the screw adjustment on the touchpiece arm should be adjusted to almost close RH fingerplate 2 (the middle fingerplate with the small hole through it), and adjusted to get a clear and in tune altissimo C# and D.
Eb and C# pads - venting determined by the adjustment from the C and B keys. If there's a split D#-E ring, the adjusting screw on the link has to be set so when the Eb pad is fully open, the lower bush pad on the split ring is fully closed.
Bell key - adjust the screw on the link so both the bell key and low B keys move together and close together, and check there's no play between the bell link and the bell key itself, and that the bell vent key pad is closing. The bell key will have more venting than the low B key, but is determined by the low B key venting. If there is no bell vent, the cork stopper on the bell key bend should be thick enough to prevent the bell key opening too much once the bell is off, but not too thick to cause double action between the bell link and the bell key.
Former oboe finisher
Howarth of London
1998 - 2010
The opinions I express are my own.
Post Edited (2007-08-07 10:51)
|
|