Illus. 02 Art.106/003161 Set of Rebuilding Screws

Caution!
Behind the mouthpiece you'll find the Buffers, These can easily slip away and if they fall on the floor you'll never find the little corner they've rolled into...

So store your spare-parts in a box, like this.

Remove of the Cover Supports.

The supports are wedged into the timber of the comb, so you'll need a pair of pincers unlock them.

The new drill-holes will be marked using a paper stencil.

Download the drilling stencil by clicking on  button (below) and printing yourself a copy.

The print-out of the 270 model/12 hole must match the width of
142,5mm exactly

The stencil is then cut to size using a pair of scissors....

...and it must exactly fit the surface of the upper reedplate.

Caution !
If the stencil doesn't fit exactly and you continue working, you will destroy your harmonica.

In the case of a stencil not being properly printed out, the fault lies with your PC and its connection to your printer-driver, a feature we have no influence over.

The stencil is now carefully fixed on the upper reedplate, using adhesive tape.

The stencil is not only good for marking new holes but it also helps to protect the valves during the operation

However, you should be aware that valves can occasionally be damaged. How to change valves you will learn at Chromatic Workshop 07.

A vertical drill including a spanning device is very much recommended here.

Okay, you've fixed the stencil to the comb and now the 5 new holes for the Screws M2 x 16 must be drilled.

Therefore insert a twist drill bit with 1,6mm dia into your drill.

This will produce the core hole for the thread M2 required for tapping the lower plate.

Place the Harmonica on a flat surface which can also be drilled into (f.e. a piece of timber).

However it would be better to use the bench-vice shown in the illustrations.

Now drill the 5 holes, one after another.

Taking care to drill only the holes marked on the stencil, drill the whole package.

The new holes are situated beneath the nails which are still holding the plates to the comb.

Holding your package firmly with your hand, allow the drill to continue at high speed.

Caution !
At driving up the drill bit it tends to get stuck.

It is not possible to drill the 4 outer holes, because the nails have not yet been removed.

Now, using the M2 Tap Bit and Universal Holder tap the M2 thread into the
lower reedplate

With the aid of a sharp flat knife, prize the lower plate carefully from the edge of the comb.

 Using this method the nails are lifted, but avoids having them fall out.

Caution!

Take care! Neither the comb nor the plate must be damaged during this operation.

 Using your pincers remove
only the 4 outside nails
 on the lower plate.

The upper plate must remain in position under the stencil.

After removing the nails, drill the 4 outside holes, but from the opposite direction -
from downside to upside.
During the drilling process, do not remove the inside nails because they are holding the lower plate in place.

Caution:
The package cannot be drilled all the way through, because the nails on the opposite side are still in position.

Now, the 4 remaining threads of the lower reedplate can be cut, using the tapper bit M2.0 and the universalholder

After removing the remaining nails, we now remove the lower plate.......

.....plus the centring-bolt, which holds the slide spring in place.

The stencil can also be removed.

Now, a Twist Drill Bit Twist-Drill Bit with a 2.0 diameter is inserted.

The new holes in the upper plate are now drilled to a diameter of 2.0mm.

However. during this process, the entire package would be drilled through.

Therefore, the lower plate is dismantled and only the upper plate and comb are drilled.

Carefully lift the upper plate with your knife, ensuring the nails do not fall out.

 Now we drill the 4 outer holes to a diameter of 2mm.

 Remove the  Twist drill bit and replace it  with one measuring about 5.0mm.

Now, using this tool countersink the 4 outer holes of the upper plate.

The upper plate is still fixed to the comb with the inner nails.

Yes, we are aware that an expert would never countersink a hole using a twist-drill bit, the job requires an additional tool, (a countersink bit) and the cost of such a tool is high, so we believe this way of doing it is defensible.

The  flat headed M2 x 16 screw must lie totally inside the countersink, because the cover will be tightened over the area and must be allowed to lay absolutely flat on the surface of the plate.

Now, the upper plate can be lifted and its nails removed.

After carefully removing all shavings and cleaning the comb thoroughly, we can begin reassembling the plates.

However it's possible we may need to exchange some damaged valves too.

How to exchange valves can be learned in Chroatic Workshop 07.

Replacing the plates

Putting the Allen screw M2 x 16 VA in place.

Tightening with the Allen screwdriver

Placing and tightening the
Flat Head Screw M2 x 16 .

Caution !
It may be possible, that you have to cut this screw depending on the thickness of the reedplate-comb.
The screw must not protrude above the surface of the plate (on both sides, remember !), because the covers have to lay flat on the surface of the reedplate on both sides of the harmonica.