Thievin' Heathen
118 posts
Dec 30, 2012
3:19 PM
|
I have not found a file I am happy with. Although I have several miniature files to choose from, it really just seems that I am scraping metal off the reed setting up a nice pre-crack area. I have discovered that a cone shaped abrasive wheel from a Dremel tool, held in my hand, can grind away brass in a nice even area. I have not seen anyone else using this method and I am concerned that others have tried it and discarded it for some reason. Burrs on the surface and edges immediately come to mind.
Has anyone else tried this?
Anyone know of any ill side effects from this method?
|
arzajac
930 posts
Dec 30, 2012
3:57 PM
|
Any method can cause burs, puncture, deform or otherwise destroy a reed beyond repair. A Dremel may work just fine if you use a really light touch - The risk that comes to mind for me is raising the pitch by 50 cents when you were aiming for five.
Burs won't ruin a reed, they can be cleaned off. But that makes for more work and if you are aiming for efficiency, that may make you pick a different tool/method.
----------
Last Edited by on Dec 30, 2012 3:58 PM
|
ElkRiverHarmonicas
1457 posts
Dec 30, 2012
8:12 PM
|
You're just moving the attachment with your hand? That sounds pretty cumbersome.
Try one of these, only put it on the actual dremel so it spins. I use it to get the reed close. If I'm making a really fine adjustment, I'll use a specially-made carbide scraper that I've got, which also works on Stainless steel reeds. Sleigh's drawscraper will work too on brass reeds.
----------
David
____________________
At the time of his birth, it was widely accepted that no one man could play that much music so well or raise that much hell. He proved them all wrong.
R.I.P. H. Cecil Payne
----------
David
Elk River Harmonicas
 
|
STME58
343 posts
Dec 31, 2012
12:17 AM
|
I don't have a lot of experience with tuning but from a mechanics of materials standpoint, scratches on the free end of the reed, where you remove material to raise the pitch, are not a problem as there is little stress there. On the root end there is high stress so scratches are more significant. You can minimize the effect of these scrapes by making sure they go along the length of the reed, not across it. I think this is the direction most people would naturally tend to scrape. From both experience and analysis, the worst place to have a scratch across the reed is about 1/4 to 1/3 od the way from the root to the tip. I am looking at a reed I replaced that failed at this point and this is where most of mine fail. A modal analysis of the reed shows this as the highest stress point. David Payne has an image from the analysis I did, showing the high stress point on the reed, on his website;
http://elkriverharmonicas.com/harp_school/reed_fatigue
I usually use 600 grit sandpaper to tune, with a business card under the reed to support it and to protect the reed plate and other reeds. It is tedious, but I don't do it often and I am new to tuning so I don't want to remove material too fast.
|
Steamrollin Stan
666 posts
Dec 31, 2012
1:08 AM
|
Reeds are so damm delicate, i'de be better off removing the apendix from and ant. Happy new year!!!!
|
Kingley
2080 posts
Dec 31, 2012
1:36 AM
|
I agree with Dave, it does sound cumbersome. I always tune use small files and reed scrapers to tune harps. When it comes to fine tuning I'd be wary of anything that could either remove too much material in one go, or was too large o that it obscured my view of what I was doing.
If it works for you though and you're happy controlling it and with the results achieved using it, I don't see any issue. There are many ways to reach the same goal. If you take embossing as an example. Many people use many different tools for that job like screwdrivers, knife blades, sockets, pennies, the UST, marbles, etc, etc.
|
ElkRiverHarmonicas
1459 posts
Dec 31, 2012
12:37 PM
|
Anytime you are talking about stress in a harmonica reed, listen to what STME58 is saying. He's got a very rare grasp on this subject and absolutely knows what he's talking about. You could literally almost drill a hole in the free end of the reed and it would be fine. There is really only one thing that will hurt a reed is a horizontal scratch at the max stress point, which is illustrated in STME58's awesome drawing.
----------
David
____________________
At the time of his birth, it was widely accepted that no one man could play that much music so well or raise that much hell. He proved them all wrong.
R.I.P. H. Cecil Payne
----------
David
Elk River Harmonicas
|
walterharp
1013 posts
Dec 31, 2012
3:52 PM
|
sad thing is how many ootb harp reeds you see tuned with a huge gash right across that stress point.. this ain't rocket science, seems like the tuning process could be just as fast without planned obsolescence. wait, they would not sell as many then...
|
