Re: [Harp-L] What's embossing?



Hi Bob,

What is embossing:
Embossing is a process of narrowing the slot in the reed plate of a
harmonica to decrease the clearance between the reed and the plate.

Why is it done:
To make the harmonica play better.

WARNING - Longer version:
Reed plates are typically made of brass.  Brass is a soft metal that does
not crack under pressure, but instead deforms or flows. By applying
pressure carefully at an angle to the edge of the reed slot, you can
actually push some of the metal down and into the slot, thereby reducing
the clearance between the reed and the plate.  As has been previously
stated, there are many youtube videos about embossing, so do a search.
You will find several different techniques - some people use a penny (U.S.
Currency).  I use a heavy-duty Exacto knife.  I have ground and polished
the blade so it is no longer sharp, but instead has a smoothed rounded
edge.

Once you have reduced the gap, it is a good idea to take a home-made
feeler gauge and run it between the reed and the reed plate to feel
whether the gap is consistent and of the right size.  Fortunately, feeler
gauges of exactly the right thickness are manufactured by the millions.
They are included inside those little white rectangular security stickers
plastered on everything from DVDs to hardware items.  Just cut open the
end of the security thingie (technical term) and you will find two perfect
shims.  Pass the shim between the slot and the reed.  If it is too tight,
you narrowed the gap too much (doh).  Most of the time you can use the
shim to trim off the excess.  If it is really tight you might have to grab
a real exacto knife to trim off some metal.  If the shim is too loose,
then give a few more passes with your embosser (penny?) and measure it
again.

As for the why emboss, sometimes you will play a harp that is really
breathy.  I don¹t know exactly how to explain it, but one harp will play
beautifully with very little air, making great sound, but another
identical harp will pass a lot of air (gas?) before it starts making
sound.  Almost always, this means the harp needs to be gapped (another
topic).  Gapping is just pressing (gently!) down on the reed to push it a
little more into the reed slot.  The breathiness is caused by the reed
being too far up from the reed plate.  Closing the gap can make a huge
difference in the playability of a harp.  But what if the reeds are
already perfectly gapped?  Well, the problem is the same - too much air
passing between the plate and the reed before the reed is forced to start
vibrating - but the cause is different.  In this case, the rectangular
hole in the reed plate is too big for the reed.  So you deform the metal
by pressing on it with an embossing tool to flow the metal into the gap,
thereby reducing the amount of free space between the plate and the reed.

Lots of words, but I hope that answers your question.  As for trashing
harps trying this, yep, sure can happen. But you would be amazed at how
tough harps can be.  If you have the covers off and you accidentally snag
a reed and bend it over, well yes, you have ruined the reed (you could
always replace it ;-).  But if you are careful, harps are actually pretty
accessible for maintenance and repair.  I would strongly suggest you start
messing around with an already trashed harp before you pick up your
favorite one to give it a tune up, but once you have opened a few covers
and bent a few reeds, you will get the hang of it.

Go for it.

Brad

On 12/6/13, 9:43 AM, "Ross Macdonald" <pdxharpdog@xxxxxxxxxxx> wrote:

>Embossing is just another way I ruin perfectly good out of the box harps!
>Ruined one last night!
>
>Arrgghh! 
>
>Save up some money and buy one from the pro harp techs instead! Can be  a
>very frustrating learning curve.
>
>Ross Macdonald
>www.sassparilla.info
>
>Sent from my iPhone
>
>On Dec 6, 2013, at 6:00 AM, Randy Redington <rwredington@xxxxxxxxx> wrote:
>
>> Don't feel bad about that Bob.
>> I know what it is but I haven't been brave enough to try it yet.
>> The concept is that you are making the space between the reed and the
>>reed
>> slot tighter, and this is supposed to make it more responsive.
>> There are a number of websites that describe the process.
>> I had the pleasure of meeting Richard Sleigh this last September.
>> He has a set of videos and tools you can get to help with this process
>>if
>> you are interested.
>> On Dec 6, 2013 7:10 AM, "bob piscura" <bpiscura@xxxxxxxxx> wrote:
>> 
>>> Now I'm letting everyone know that I'm real new to the harp world.
>>>What
>>> is embossing and why is it done?
>>> BOB PISCURA
>>> 
>>> 
>





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