Re: [Harp-L] New process for treating reeds



>
> All reedplates at every Chinese harmonica factory I've visited are baked
> prior to adjusting and tuning in order to de-tension them.  The reason for
> this is that Chinese reeds, being much softer than German reeds, are
> drastically deformed after being stamped out and riveted to their
> reedplates.  They are stacked together about 6 inches high with thin shims
> supporting the reeds and separated by blank plates with cutouts to avoid
> contact with the rivet pads, then bolted down tight in steel frames.  They
> come out of the oven lying nice and flat, with minimal work required to gap
> them thereafter.  The prepared reedplates are placed in a cold oven, which
> is gradually brought up to, I seem to recall, around 400 or 500 degrees F
> and baked for around 4 hours, then gradually brought back down to room
> temperature.




> German reeds, being made of stiffer material, are not subject to the same
> deformation that Chinese reeds are during production and don't require heat
> treating to regain the correct shape.  They do, however, need and are given
> by Hohner a rest period (Ruhezeit) of some days in order to de-tension
> before they are tuned.  It's my understanding that the only advantage to
> heat treating the reeds over giving them a rest period is in time saving.
>  In one of the articles I wrote for Hohner's EasyReeding magazine about
> adjusting and tuning reeds, I recommended giving the reeds a rest period
> after adjusting their curvature and gap and before their first tuning, and
> then another rest period before going over their tuning again.  These rest
> periods help the reeds to better maintain their tuning.


Hohner tested cryogenically treated reedplates years ago and found that
there was a minor improvement in durability.  I played these samples and
found a only slight improvement in playability.  The cost of treating the
reedplates in this manner was not considered to be worth the relatively
minor improvement in quality, compared to other quality improvements which
were implemented.

Best regards,
Rick Epping


>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Wed, 24 Sep 2008 00:11:12 -0500
> From: "Harvey Berman" <cscharp@xxxxxxxxxxxxx>
> Subject: [Harp-L] New process for treaing reeds
> To: <harp-l@xxxxxxxxxx>
> Message-ID: <62481104469648CE95B602ECE4CE9B16@harveyh9luqp7f>
> Content-Type: text/plain;       charset="iso-8859-1"
>
> When I first started blowing harps, about 10 years ago or so, I blew out
> mostly 4 and 5 draw reeds at least once or twice in a 4 hour gig.  I bought
> a bunch of different kinds of harps and had the same experience with all of
> them.  I was telling a friend, who was an engineer about my problems and he
> suggested that tried to cryogenically treat them.  Cryogenics is a process
> where you freeze items with liquid nitrogen at a controlled rate and then
> bring them back at another controlled rate.  It seems that machine tools are
> treated and they last substantially longer than untreated ones.  Also
> supposedly the reason that razor blades last so much longer now than they
> used to was because of the treatment.  It is supposed to relax and line up
> the molecules, and relieve the stress gained in the manufacturing process.
>
> I was put in touch with a company in Toledo Ohio, and discussed it with
> them, and they said that they do brass instruments for the local Symphony
> and other musicians, and that the Horn Players are very happy with the
> results, and they reported that there was a big improvement in sound.  The
> treatment is not expensive, but they charge by the pound, and there was a
> minimum charge of about $50 if I remember correctly. I could not come up
> with enough reed plates to make up a good order, so I got together with
> Dwight Grimm, of That One Dude Harp Fame, and we sent in a bunch of plates
> to be frozen.  I think that Dwight reported our project to Harp-l back then.
>  When we got the plates back, a week or so later, I anticipated a great
> improvement in both sound, and longevity.  Well, the sound didn't change
> that I could tell.  My tone sucked before and after the freezing, and still
> does today.  However, I did not seem to blow out harps at the same rate as I
> did before.  I think the rea!
>  lity of it was that I was learning not to blow so hard.
>
> I happened to go the BHF that year, and I got into a conversation with Rick
> Epping, and told him of my efforts, and asked his opinion.  He stated, if I
> remember correctly, that he had heard of it, and his opinion was that it was
> a real thing, and could prolong the like of Harmonica Reeds.  When I asked
> him why Hohner did not go ahead and treat them at the factory, I left with
> the impression that it was not in their best interest to make them last
> longer. Of course the is IMHO.  I do know that some guitar strings are
> cryogenically treated, but I do not know what the benefits are in that
> situation.  I would imagine that the process of manipulating the reeds, and
> tuning them would add those stresses right back to the reeds.Who knows?
>
> Now, I do not blow out too many reeds, and I am still playing some of the
> ones I had frozen.  Of course, thank to all of you guys I now work on my
> own, and I do not have to blow as hard to get the volume I need.
>
> Well, Back to lurking.
>
>
>
> Date: Tue, 23 Sep 2008 18:34:19 -0700 (PDT)
> From: David Payne <dave@xxxxxxxxxxxxxxxxxxxxxx>
> Subject: [Harp-L] New process for treating reeds
> To: Harp L Harp L <harp-l@xxxxxxxxxx>
> Message-ID: <79076.25104.qm@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx>
> Content-Type: text/plain; charset=iso-8859-1
>
> It's probably been done before, I've been working and thinking for a year
> on this... -and I'm mentioning it now, so hopefully others won't have to go
> through the same amount of work... annealing reeds, although what the
> process I got in the end isn't exactly annealing and I'm getting good enough
> results now to mention it to folks. What got me thinking of this was
> something carried over from guns, when you reload brass rifle cartridges,
> before you load, you have to heat treat the cartridge brass to relieve the
> stress in the metal. Everytime you shoot a shell, stress builds up in the
> brass, so you anneal to soften the brass and relieve the stress in the
> metal. If you don't, eventually the brass is going to split when you shoot
> the cartridge.
> Harmonica reeds are certainly under less stress than the brass in a rifle
> shell. So, I got to thinking, what if I applied that process to harmonicas?
> Harmonica reeds have inherent metal stress in them from the factory. I
> thought that if I could relieve that stress in the metal, the reeds would
> maybe last longer... and I prefer - probably since I was a Marine Band
> player for 25 years - narrow, brass reeds. So, I've been working for a long
> time on things I could do to make my own improvements to the Seydel Solist.
> Many, many thanks to Randy Sandoval for educating me on metals... many
> thanks, he really helped me eliminate a good bit of trial and error. I've
> experiemented with different kinds of heating, heating in different places,
> heating for different times, different temps, quenching, not quenching, etc.
> Anyway, I've found something that apparently works. I've got a couple of Ds
> now I'm working on for some guys, so I used those for the first official use
> of this process.
> The breakthrough was stopping short of annealing. Instead of using a high
> temperature, I used a lower temperature for a longer period of time. I had
> been getting close to this, but was still experimenting for the best temp,
> when Randy sent me something that said between 250 and 300 degrees would not
> make the brass softer (anneal), but would instead relieve the inherent
> stress in the metal and not change its temper.
>
> Today was the first time I did this for somebody's order. I was thinking
> longevity, which can not be tested this early, but what I got was a very
> noticeable improvement in response and a slight increase in volume... the
> difference was like how you feel when you go in and leave a chiropractor,
> perhaps for similar reasons. There was a very noticeable improvement... and
> it wasn't psycological because I wasn't expecting ANY improvement in
> response. But I got it.
>
> Another interesting note, there was one reed that took more effort to gap
> than the others... a 2 blow. I gapped and embossed before heat treating and
> after the treatment, all the gaps were the same. Except that 2 blow. It was
> way high. Now the gap adjustment is smoother... just an observation.
>
> Here's the process, it's so simple to describe, I kind of feel like a
> jackass for having worked at it so long. Time will tell if I can repeat
> these results over time...
>
> Take two reedplates 500 degrees in the oven for one hour, cool at room
> temperature.
>
>



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