Re: [Harp-L] Tension Headache

[Joe Leone <3n037@xxxxxxxxxxx>]

On May 9, 2011, at 9:57 PM, Elizabeth Hess wrote:

> Okay, so, while waiting for my valved harps and PT Gazell valves to arrive, I decided to bear down and try to set up one of my harps for overblows.  I heard a rumor that after you learn a certain amount about how to do it, the key thing is determination.  So far this seems partly true.
> 
> I have arced and gapped the reeds on my Bb Special 20.  I contrived a light box, and have embossed the reed slots of 4, 5, and 6. You know how, sometimes, when you're part way through cleaning a room, and it looks worse before it looks better?  That's how my week has been.  Early on, I got some pretty robust overblows on 4, 5, an 6.  Then I got greedy and tried to get 1 overblow.  Put the harp back together, and couldn't get 4, 5, or 6 for nuthin'.
> 
> Searched the archives to see if anyone had written anything definitive on why plinking is better than putting the reed plate up to your mouth and drawing air through to sound the reed (per Rupert's DVD -- Hi, Rupert!).  Didn't find anything definitive on that, but Smokey Joe is a genius:  He wrote that instead of screwing the harp back together every time, you can take two large binder clips -- the black ones made of spring steel -- clamp them on the ends, and try out your modification without all that screwing and unscrewing every time.  I tried it, and darned if I didn't get 4, 5 and 6 overblows again.  Screwed the harp back together, couldn't get them.  Backed the interior screws off a bit (Did I have them so tight that I was warping the reed plates?),

Maybe, but answer is below. 

> but no joy.  Gapped and embossed too far, backed off, back and forth, stayed in denial and just tried for determination...   last couple of days:  bupkis.
> 
> Just now I disassembled the harp, held it together gently, and didn't I overblow 4, 5, and 6 as just nicely as you please.  Put on the binder clips, and lost the overblow on chamber 5.  Took the clips back off and got it, again.  Can anyone explain what's going on, here, and what the remedy is?

Yes. 

>  Besides using the binder clips permanently, that is:  They make my harp look like an elongated X-Wing Fighter, which is kind of cool, but it won't fit in the case, and once a clip flew off and might have maimed someone, had someone been standing there.  I can't afford that kind of risk in the long term.
> 
> Thanks in advance.
> 
> Oh, and I was traveling when Michelle asked why people wanted so much to play chromatic notes on diatonic harps.  My reason:  Gluttony.
> 
> Elizabeth
> 
Your harp is suffering from ' crooked door frame syndrome'. Let me explain. Please. 

Imagine that you have just installed a door frame. And you are standing inside facing it. You measured the opening and it was 32 1/8" (the proper amount). But what you DIDN't realize was that within the 4" width of the frame, there was a deviation. The INSIDE of the frame (the edge facing you) was 32 1/8", BUT the edge facing outdoors was  only 32 1/16". You wanted the door to be tight. For security reasons. You don't want to leave any room for someone to stick in a shim and jimmy your lock. But when you go to mount the door, it is too tight and won't fit. Why? because the cant of the frame has changed the dimensions that you needed. (Key: doors are oversized anyway with the idea that they will be finish planed).

When you had the binder clips on the ends, you made a belly ever so slight in the plate. Hardly descernible with the naked eye. But there none the less. The clips have a foot pound rating of (I'm guessing) 75 to 80 foot pounds. If you were to apply one to your finger, it would exert as much pressure as if you had your finger under the leg of a loaded chest of drawers. So, embossing will exascerbate this problem because you were already working with a fairly small dimension. And now, you made it even smaller. 
So, visualize looking at the cross section of the reed slots and you will find that even this slight belly in relation to the small reed plate can be extrapolated to the 1/16th" in relation to a full sized door. 

Ergo, the slot is now too tight. Backing off the pressure will allow the plate to flatten out enough just enough that the deviation disappears and you now are SQUARE in the slot. When I use binder clips, I sometimes put them at the BACK of the plates. And even if they rest on the rivets, that shouldn't make a difference. Now at the high end (where the reeds are short and leave a lot of plate), the clips can take a deeper bite thus spreading the load more evenly.