Thievin' Heathen
587 posts
Aug 16, 2015
9:44 AM
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I have seen "Polished Reeds" mentioned in relation to custom harps a few times. I don't know exactly how this is accomplished. I have put a buffing wheel with polishing compound on my Dremel and polished a few reeds but I have given up the practice out of concern for the heat. Those little reeds get hot quick. I seem to recall things going flat after being polished.
Are my concerns legitimate?
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STME58
1442 posts
Aug 16, 2015
1:54 PM
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From a mechanics of materials standpoint, a polished surface is much less susceptible to fatigue failure than a rough one. I don't know what the temper state of reeds are in as delivered harps. If they were tempered and you heated them above the annealing point (~700 deg C for steel) you could soften the metal. Softer means it would bend and take a set easier. Very hard metals break before they bend and take a set.
The pitch of the reed is determined by its stiffness and its mass. When you polish a reed you change both of these so you can expect you will need to re-tune after polishing. The critical area to have polished is from the root of the reed to about half way out. The tip of the reed moves but does not flex so this is a good place to remove material for tuning as the scratches in this area won't matter. Removing material at the tip raises the pitch. to lower the pitch you need to either add material at the tip or reduce the stiffness by thinning near the root. If you leave rough areas or scratches near the root this could reduce the life of the reed.
 This image shows a failed reed and a finite element analysis (FEA) I did of that reed. The red areas are the highest stress and where the FEA predicts failure will occur. The red and green areas are where polishing will have the most effect.
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GMaj7
739 posts
Aug 16, 2015
5:53 PM
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I polish reeds on almost all of my diatonic and chromatic Seydel repairs. However, most of these are stainless steel reeds, although a few are brass.
I don't think polished reeds will improve one's playing or make them any closer to Howard Levi or Jason Ricci. However, I can say that I mark all my repairs and very few polished reeds break or fail.
Some extremely talented players report that the polished reeds play a little better, but I would be cautious about making any claim to this.
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Greg Jones
16:23 Custom Harmonicas
greg@1623customharmonicas.com
1623customharmonicas.com
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chromaticblues
1689 posts
Aug 22, 2015
5:37 AM
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I would NEVER use a dremel or any power tool. All you should be trying to do is remove the milling marks and/or the tuning marks from the factory on the section of the reed closest to the rivet. It is not needed to "polish" any more than that. I don't like using the word "polish", because you have sand the milling marks down, but you can only sand very little on new Hohner harps because the reeds are so thin. Older Hohner harps have thicker reeds in this area and do improve greatly by sandng the milling marks/tuning gafs. This has to be very carfully and with very fine sanding wands.
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Gnarly
1447 posts
Aug 22, 2015
9:16 AM
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I use a Dremel style tool and Shofu Brownie polishing bits, and recently acquired a plug in style attenuator from Radio Shack, so I can get it to go as slow as I like.
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GMaj7
747 posts
Aug 22, 2015
9:44 AM
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I use a powered reamer with no torque and a silicon bit.
Conservatively speaking, I polish about 25 a week.
Not sure about the other advice up here but that's the way I do it.
Gnarly would be the category of folks who know how to do this, too...
I guess you could use sanding wands, but if this takes me longer than 3 minutes, I'm losing money.
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Greg Jones
16:23 Custom Harmonicas
greg@1623customharmonicas.com
1623customharmonicas.com
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mlefree
375 posts
Aug 22, 2015
1:26 PM
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Acknowledged master harmonica technician, co-creator of the fabled "Renaissance" chromatic harmonica and chromatic virtuoso himself, Douglas Tate would agree with Greg. He advised polishing reeds way back in 1999 when he published his book "How To Make Your Harmonica Work Better," one of my first references on how to work on harmonicas.
FWIW as I recall, though, he used sanding wands.
Michelle
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SilverWingLeather.com
email: mlefree@silverwingleather.com
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Greg Heumann
3084 posts
Aug 22, 2015
7:20 PM
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Polishing, like anything else is a skill and an art. You can polish scratches out of plastic with a dremel, but heat buildup will ruin the piece very quickly. I learned how to polish scratches out of plastic watch bezels, eye glasses and even lacquer with a Dremel. YOU have to control the heat! Period. How fast heat builds up depends on the material, the polishing tool and its diameter, the abrasive in use, the RPM, and the pressure. MOST of these are under your control.
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***************************************************
/Greg
BlowsMeAway Productions
See my Customer Mics album on Facebook
Bluestate on iTunes
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chromaticblues
1690 posts
Aug 22, 2015
8:20 PM
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Anyone using dremels or any other power tools is trying to do it fast to make money! Not trying to do the best job possible! I don't care who does it!!
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boris_plotnikov
1078 posts
Aug 23, 2015
4:40 AM
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I just get a harmonica half tone higher and tune it down by accurate even lenghtwise removing reed material using rotary tool. It leads to slightly thinner reed than on regular key. in case of Seydel stainless steel reeds this techniqe gives me more overtones and faster responce (but a bit less volume). And theoretically it have to lead to more durable reeds, as I remove milling marks. All my best instruments are made using thistechnique.
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Excuse my bad English.
My videos.
Last Edited by boris_plotnikov on Aug 23, 2015 4:41 AM
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GMaj7
749 posts
Aug 23, 2015
9:17 AM
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Hey Chromatic Blues,
There is a high probability that the guys doing it to make money, know more and do a better job. I put myself squarely in that category.
I'll match mine to anyone out there. When you do something often enough, you learn it.
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Greg Jones
16:23 Custom Harmonicas
greg@1623customharmonicas.com
1623customharmonicas.com
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Thievin' Heathen
593 posts
Aug 23, 2015
9:41 AM
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Lots of interesting ideas. Looking into Greg's method, I found the silicone polishing bit to be impregnated with their own abrasives. I think Boris might find these useful in taking stainless steel Seydels down a half step. That has to be a lot of precision work. Maybe that's what he uses?
I think Greg's power reamer is spinning much slower than I have been going with my Dremel.
Somewhere along the way, I started using polishing compounds on cotton wheels. Yesterday, I purchased a package of wood shafted Q-tips. I have high hopes for these, used with polishing compound. They hold up well and are effective. I also discovered I can cut all but about 1 inch off the shaft and chuck them into my $10 Harbor Freight rotary tool. It spins pretty slow.
Thanks for all the suggestions.
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Greg Heumann
3086 posts
Aug 23, 2015
10:22 PM
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There's no advantage to turning slower except that polishing takes longer. Yes, there is a speed below which it is hard to do damage. But a pro can use a fast tool successfully.
This is true for polishing automotive paint as much as it is for anything else. Amateurs use an orbital buffer because without practice and training they will burn through the paint if they use a rotary polisher. But you won't find orbitals in body shops. They use rotary ones because the get the job done 10 times faster or more.
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***************************************************
/Greg
BlowsMeAway Productions
See my Customer Mics album on Facebook
Bluestate on iTunes
Last Edited by Greg Heumann on Aug 23, 2015 10:24 PM
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