Sunday, January 15, 2012

Hohner 64 Chromonica 280

The Hohner 64 Chromonica 280 chromatic is one of three Hohner models of 16 holers.  In this group are included the regular 64, the Super 64 and the Super 64X.  An older fourth version, also dubbed 64 chromonica 280, has a wooden comb and the reeds plates are nailed, just like the Super chromonica 270, but I count the model among the regular 64.

I have a regular 64, a Super 64 and a Super 64x  which are shown in the following picture:



Moving up from the regular 64 to the more modern looking  Super 64X is like being transported in time from Sherlock Holmes' to 007's.

The regular 64 and the Super 64 are almost identical except that the Super 64 has a streamlined look on account of the tapered ends of the plate covers, while the regular 64 still carries the old Hohner tradition of squared corners. However, the Super 64X is set apart from its older "brothers" with a gold-plated mouthpiece assembly and studs, see-through natural finish, plexiglass comb, thicker,  modernized brass reeds plate, on top of contrasting colors of heavy black and gold.

I reserve this space for the discussion of the regular 64 and other two models will be dealt in later posts.

Here are the notes of this 16-holer:






The notes chart of the regular 64 is identical to its younger brothers, the Super 64 and the Super 64x.  These 16 holers are capable of producing 64 notes, or 4 notes from each hole.  The notes are set cross-tuned in 4 octaves, with each set of 4 holes constituting one complete notes of scale.  The older, wooden-combed 64 is easily distinguished from the later Hohner 64 models because the holes in the mouthpiece in the older harp are lined up straight, in other words, the older 64 is straight-tuned.

The first four holes of the 64s are extra lower notes, lower than the lowest notes of  the Super 270, which means that the regular 64 is actually a 270 padded with four additional holes, which are the equivalent of an octave of low notes. Thus, the numbers etched on the cover plate are not numbers 1 to 16, but 1 to 4, then 1 to 12.

I like the sound of the regular 64.  The melody that comes from the lower notes seem to ramble through the air like a solo-playing trombone, while the swarming middle notes seem to sound once a saxophone then a violin.  I think the regular 64, or the 280, has totally drawfed its kid brother,  the Super Chromonica 270, and the big brother, or the "battleship", a name someone has coined for it, will likely push the "kid" to the back stage.


Here is a sample of music from the regular 64:


Here is another piece:




DISASSEMBLY
I always open up a harmonica just to see what is inside.   Here is the semi disassembled view of the regular 64:


The comb of the model in the picture is synthetic, but older models have wooden combs too, just like the Super 270.  However, the regular 64 carries over Hohner's tradition of using nails to hold together the comb assembly. This design has been discontinued in the Super 64 onward with the use fastening screws.  And like the 270, the reeds plates are attached to the plastic comb with nails, or better still with spikes, that are pressed fit in one reeds plate and through to the opposite reeds plate.  Anyone intending to take apart the comb assembly of the regular 64 should think twice before proceeding.

But I was undaunted, perhaps because of having done this kind of procedure very easily on several Super 270s and I thought it would similarly be an easy job to take apart the regular 64.   And take apart I did, because I wanted to see the inside and replace the "spikes" with screws, to make easier the job of cleaning or repair. If only I knew what I know now, i.e., it is not a joke to separate the spikes from the reeds plates, I would have preferred keeping the comb assembly intact, but I went ahead and almost lost a very nice Hohner 64 chromonica 280.

The difficult part is removing the spikes from the reeds plates. The spikes stays with the plates after separating the plates from the comb because the spikes are pressed fit into the hole of the reeds plate. In other words, the plastic comb is not pierced by the spikes, but is provided with holes for the spikes to go through to the opposite reeds plate, which means that for the reeds plates to hold fast to the comb, the spikes must press fit to the opposite plate.  This design is like a simulation of the screwed design now used on most modern harmonicas and a departure from the design of the Super 270 where the reeds plates are literally nailed  to the comb. In the regular 64, one reeds plate is "nailed" to the other reeds plate,  and the comb is sandwiched in between.

In separating the comb assembly, I employed the technique that works well with the Super 270s, i.e., using a one edge blade alternated by a box cutter blade to ease out the reeds plate from the comb.  And with the help of a plier I pushed down the pointed end of the spike.  I was able to separate both plates from the comb.  But, as mentioned earlier the spikes were still in the reeds plate and I am now faced with the very difficult task - removing the spikes from the  reeds plates. 

First, I tried pulling out the spikes from the reeds plate with a plier with all my strength.  But the spike passively resisted and I was successful in one only after an ardous struggle.  So I rested for quite a while thinking of a better way to remove the spikes.  Finally I thought of shortening the travel of the spike in the hole, and the way to do this is cut the spike near the hole and then pull with the plier.  Using a wire cutter I cut the spike all the way into the very surface of the plate and pulled out the remaining spike with a plier.  It was too much an easy job pulling out the rest of the spikes from there on.

These are all the tools I used to do the job:


I took a video of this procedure but  it still has the unnecessary clips.  As soon as I am done with editing, I will have it posted here.

So, here is the fully disassembled view of the regular 64:


The screws shown on the left side are replacements to the spikes that were discarded.  I used a 2mm x 16mm  size machine screws and the holes in the entry reeds plate are size 5/64", while the exit holes in the opposite reeds plate are size 1/16".  To avoid confusion, I did not follow the original alternating pattern of the spikes - head, point, head arrangement, but confined the entry holes in one plate and the exit holes in the other plate.  I also tapped the exit holes because the machine screws were not self-tapping.  I would have preferred self-tapping screws but I could not find any in the market.  The smallest I found is size 2.2mm x 15.9mm, but the 4mm head of this screw is just too big to risk as it might throw off the plate cover out of position.  Or, I could have drilled one size holes and use nuts, but for personal aesthetic bias I prefer the look of the protruding thread end, which is how the comb assembly of later models of most harmonicas look.

Note also that the slider assembly has only two parts, the back plate and the slider.  There is no cover plate  as in the Super 270 because the mouthpiece has been redesigned to act as the cover plate of the slider.  

Another key design difference between the 280 and the 270:  the hole in the slider of the 280 is situated not in the middle of the slider, but on its side, unlike in the 270 which is in the middle.  The 280 design prevents  an incorrect reassembly of the slider because there is only one correct fit of the wire spring into the tiny hole of the slider.

REASSEMBLY
The first hurdle in reassembly is finding the correct side of the comb to attach the reeds plate.  This would not be a problem if the match was marked after the disassembly.  Otherwise, here is the step by step reassembly procedure.  

Step 1 - Install the slider wire spring.  The wire spring is installed inside a rectangular space at the end of the comb where the shorter reeds are positioned.  The longer end of the spring goes out of the rectangular hole on top of the comb, the eye fits into the round seat, and the shorter end is coiled inside its housing, and is pushed to fit with a flat screwdriver.  

Step 2 - Match the reeds plates with the comb.  The correct match should have the two reeds plate fit into the guide at the base of the comb and the one that go to the side of the comb where the spring is fitted should have a windsaver as first in the row of alternating reeds and windsavers. Otherwise, the plate should go to the other side of the comb.  This first windsaver actually covers the blow reed that plays the lowest note, which is a C.

Step 3 - Install the screws.  Recall that the removal of the nails or spikes has rendered them useless, so replacement screws had to be fitted.  It may be possible to install spare nails from Hohner (I have not asked Hohner about this, but I would think it will be much more a problem fitting the nails, than tapping the holes for the replacement screws.  In working with the comb, I was hesitant to lay it flat on a surface and apply some force on it for fear of damaging the windsavers or the reeds.)

Step 4 - Install the studs.  These are the small leaf-like shaped four pieces of brass which are pre-positioned near the center of the comb to serve as support studs for the cover plate.

Step 5 - Prepare the cover plate for each side of the comb.  The plate with the numbers must be placed on top of the comb assembly, i.e., the side facing the sky with the harp in playing position. 

Step 6 - Install the cover plate bolts and tighten.  

Step 7 - Install the slider and the mouthpiece.  This is a very delicate operation and must be done with care because an incorrect reassembly can damage the slider.  Follow these steps: 

a) position the comb with the short reeds section on the right  side; 

b) place the slider back plate on top of the comb, with the wire spring positioned inside the rectangular hole of the back plate;   

c) fit the wire into the tiny hole of the slider and lay the slider along the comb on top of the back plate; 

d) prepare the  mouthpiece and the two screws -  insert screw no. 1 into the hole on the mouthpiece end with the lug and screw no. 2 in the other end and secure both with the plastic bushing; 

e)  position the end of the comb where screw no. 2 is located against a stopper, or something to hold it back;

f) place the mouthpiece with the screws on top of the slider, making sure that the mouthpiece end with screw no. 1 sits top of the wire spring; 

g)  slightly tighten screw no. 2 just enough to hold the mouthpiece; 

h) push the slider slightly to position its hole on top of the hole of back plate and lightly tighten screw no. 1;  

i)  complete the tightening of the full torque of the two screws while making sure that the mouthpiece is correctly fitted into the slider. 

j) test the function of the slider for smooth operation and untighten the screws as needed.

Here is my own specification of the location of screw no. 1 and 2 in the reassembly of the mouthpiece:


I have a video showing this reassembly procedure, but I need to clean it first with unnecessary clips, and when I am done I will have it posted here.









9 comments:

  1. Hi Vir. This is really amazing! You are amazing....was just wondering why you thought of disassembling and reassembling..quite a tedious task. You should have been a mechanical engineer and not a CPA hahaha!, ......removing the spikes from the the reeds plate....i hardly understand the terms but i did enjoy reading this. Great!

    ReplyDelete
    Replies
    1. Thanks for the nice words. I actually find enjoyment in tinkering with these little things.

      Delete
  2. Mr Leynes, Im an armonica player in colombia/south america. resently i encounter a problem with my chromonica 280C regular 64. the 6th hole doesnt sound but the mecanisim seems to be working, also the last holes doesnt sound great using the handabr. Any chance you know how to fix it? I will appreciate it greatly thanks for your time :D

    ReplyDelete
    Replies
    1. Is your 64 zigzag or straight construction? In straight construction all active reeds are located in top plate with slider out. If slider is in the active reeds are in the bottom plate. In zigzag, the active reeds alternate between top and bottom plates. Anyway, I presume you know in which plate the errant 6th reed you are talking about is located. You'll have to remove the cover to see the valves and the reeds and do correction. The most common cause of no sound is a stuck valve. You can correct this by lifting the valve with a blade or a pin depending on whether it is a blow or draw reed. A blow reed with stuck valve is easy to fix because the valve is located outside and you can use a blade to lift it up. If the reed is draw, the valve is located inside and you have to use a pin and insert it under the reed to access the valve and free it up. The other possible cause is incorrect gap of the reed - it may be close, too narrow or too large. If it is hard to blow or draw the gap may be close or too narrow. If it is easy to blow or draw but no sound, or the sound is delayed, the gap may be too large. The reed of the draw is located on the outside so it is easy to inspect and adjust. The reed of the blow is in the inside and covered by the valve. To access the blow reed you have to work under the valve and push it gently with a pin to widen it. To narrow it you access the reed from the mouthpiece hole and gently push it with a bent wire toward the outside. Similar gap problems can affect the reeds of the higher notes.

      Delete
  3. I've a quick question:
    Would it be possible to buy a Super 64X and replace the covers of it with the covers of the old 280? Would it fit? I like the older traditional style a little more 😅

    ReplyDelete
  4. The cover bolt of the 64x and the regular 280 holes match, but the 64x has studs at the bottom corners that prevent the 280 cover from getting flushed to the reeds plate.

    ReplyDelete
  5. This comment has been removed by the author.

    ReplyDelete
  6. Hello sir,
    Do you still happen to have the video of the disassembly by any chance? I'd be very interested in taking a look at it, even if it is unedited. And thank you for this very useful article, with it's help I'm hoping to replace a broken slider.

    ReplyDelete
  7. The 2021 ford escape titanium hybrid - iTanium-arts.com
    The titanium connecting rod 2021 is back. With the new version of the titanium wire hit casino, 2021 titanium white octane blueprint Casino Games titanium gr 2 2021 - Best Bonuses, titanium bolt Best Live Casino, Best Table Games.

    ReplyDelete