Measures and tolerances should be calculated previously in order to obtain the details according to the thickness required for the treatment.
Oxide (and consequently also G.H.A.®) grows directly on the base of aluminum, penetrating internally for half the total thickness. This means that on a flat surface, on a 50 μm carry over, the final result will be a 25 μm surface increase.
When we talk of tolerated holes instead, the final growth of the diameter will be exactly the same as the applied yield. This means that a hole tolerated on a 50 μm carry should be initially wider than 50 μm
In some cases it is also possible to protect areas and holes tolerated with plugs, tapes for galvanic or special paints; In this case it is correct to calculate the odds with the final values, considering that they will not be affected by the treatment. For more information, please visit the Protection section.