Re: [Harp-L] Chromatic customizing

["Vern Smith" <jevern@xxxxxxx>]

----- Original Message ----- 
From: "David Payne" <dave@xxxxxxxxxxxxxxxxxxxxxx>
To: "Harp L Harp L" <harp-l@xxxxxxxxxx>
Sent: Monday, February 18, 2008 5:28 PM
Subject: [Harp-L] Chromatic customizing


> Trying to get an idea what other guys are doing. Specifically, I'm 
> wondering about the slide. Machining new parts aside, what do you guys do 
> to make the slide a little more air tight?

This subject is covered in both Tate's and Schackner's books, referring to 
the 270-type chromatic.  You carefully and accurately reduce the excess 
height of the little turned-up flanges on the U-channel.

I am sending your inquiry via BCC to some techs who have special equipment 
for the task and might be persuaded to do it for a fee.  If they are 
interested, they'll email you.

The clearance in the slides is variable up to .007" as a 270 comes from the 
factory.  I like mine reduced to .002".  It is ticklish business so be very 
careful or have it done by an expert.   I also rub the parts of the slide 
with crocus cloth to make them smooth and wax them with Johnson's (carnauba) 
paste floor wax.  The wax gives a little lubrication but is mainly to 
prevent saliva from sticking in the slide.

IMO, reducing slide clearance will contribute more to the responsiveness of 
your harp than any other modification.

No matter what else you do, you will still have a lot of leakage without 
valves.  Especially at the low end of the harp, the opening (not sounding) 
reed already has a big gap and opens even wider in response to your breath 
pressure.  This flow passage has many times the area of the clearance 
between the sounding reed and its slot. If you do not use valves, then you 
won't notice any improvement from embossing, arcing, or modification of the 
slide.

> The specific harp I'm working on right now is a Borrah Minnevitch slide 
> harp Chrom from the 1920s, external slide spring (which I think looks 
> really cool), etc. This harp has no windsavers. I'm wanting to keep it 
> that way if possible, I'm embossing and arcing the reeds now to make it a 
> little more tight. I'd like to make the slide a little tighter, if 
> possible. If I can't get the slide any tighter, I'll probably half valve 
> it.
>
> Dave
>
> ______________________
> Dave Payne Sr.
> Elk River Harmonicas
> www.elkriverharmonicas.com
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