Re: [Harp-L] Shortening slots

[Joe and Cass Leone <leone@xxxxxxxx>]

On Apr 12, 2008, at 1:09 AM, Paul Bowering wrote:

> I came up with a fairly radical but potentially great altered tuning.

Ok, and since you don't specify whether you are tuning up or down,  
this leaves some questions. Far be it for me to ask what the tuning  
is because I have found out (the hard way) that sometimes, one's own  
tuning is something to covet. So, I won't ask for you to expound.

> The problem is that the first hole would require too great a retune  
> to be feasible.

Ok, again, I don't know which way you are going, but assume that you  
are going UP and the amount of material you would have to remove from  
the reed would be too great. Inasmuch as most up tuning is done on  
the free end's 30%, one comes to a point where the tip of the reed  
would be the thinness of foil. This is never stable.

> I planned to simply replace the reed but taking a reed from a short  
> slot plate to put in a long slot plate doesn't work either.

Ok, again, because you seem to want to use a short reed, I assume you  
want to tune UP.

> Any suggestions on how to fill in the slot a little to make it  
> shorter?

There are many ways to do this job. But as customization tricks are  
even more closely guarded than your tuning, I would suspect that only  
a few people (who have no rice bowl to protect) will give you any  
definitive answers.

1... I would first try to use the existing reed. This may entail  
shaving the reed to wind up a sliver of metal that is just out and  
out plain easier to work with. The trade off could be lower durability.
2... If you are working with a weighted end, the proper procedure is  
to take metal away from the REAR of the weight. (In other words the  
edge towards the rivet pad or boss.
3... Naturally you want to try to stay away fro the 70% of the reed  
that will either take you neutral or down in pitch.
4... Using a smaller (shorter) reed, entails exactly how much you are  
dealing with in length.

5... If we're talking 1 mm or less here, I would suggest two things.
6... Move the rivet hole (take a piece of brass (or copper) wire and  
fill the existing rivet hole in the PLATE. Trim it flush with emory  
board. Drill another hole by centering the 'wire sized' bit (a tiny  
bit smaller than the rivet dia) ON the SEAM of the wire AND the plate  
brass in the direction you wish to go. In your case, that may be the  
seam closest to the dead end of the reed. This will already move the  
reed 1/2 mm and close up the slot tolerance.
7... Then you can take a nail set with which the tip has been ground/ 
filed to a SQUARE. It will need to be at least 2mm. Now placing this  
nail set with the leading edge 1 mm FROM the end of the free swinging  
end of the slot, punch a depression into the brass. This will swage  
some brass INTO the end of the slot. Don't expect more than 1/2 mm.

8... For distances greater than 1mm (total), I would take a piece of  
brass or copper (maybe a scrap reed with a weighted end). Stand it up  
in the end of the slot and solder in place. After set time, slice off  
the dangling participle, file the top & bottom and blend it in with  
the reed plate. This will give you a sharp clean edge for the reed to  
'work' against. For really wide gaps, you will need to make a pin or  
plug from a larger piece of scrap brass. I have cigar boxes of itsy  
bitsy electronical parts around, so scout around. Some times a  
machine screw filed square will work. There is even the possibility  
of screwing a machine screw INTO the end of the reed slot and THEN  
after 'flush' cutting it top and bottom, filing the working side square.
9... These are the quick and dirty methods. I have made reeds out of  
razor blades, flattened bullet casings. It's all a gross amount of  
work but if you're young and have steady hands, the challenge is fun.  
It gives you a sense of accomplishment.

Good luck with your project, and BTW, Vern's method is coming from an  
engineering standpoint and is a permanent job.

smokey-joe

> Paul
>
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