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I have defined Plated through holes on my PCB design.But somehow my pcb manufacturer has drilled it as non plated through hole and PCB has arrived.Now I need a suggestion to convert this non plated through hole to plated through hole using wire /solder pin.

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First you should contact the PCB vendor and try to get them to remake the boards correctly. If this is not possible you could try making the repairs yourself as follows:

If the hole takes a through hole component just be sure to manually solder each pin at both sides. If the hole is a via from an outer surface to the opposite outer surface then a simple fine wire or pin soldered at both ends should do. (If the via is expected to pass a high current use a thicker wire.) If the board is to be wave soldered or put through an SMT oven be sure to bend the wire or pin at both sides to prevent it from falling out.

If the hole or via needs to connect to an inner layer then you have much bigger problem. If you absolutely must solve this type of problem (on a limited number of holes) you could try using a small flat tipped drill (this might be known as a milling bit), the drill diameter should be smaller then the upper pad. Very carefully drill out the hole just enough to access the foil pad on the next inner layer, then solder the inner pad to the other layers with fine wire. If it is a 4 layer connection then repeat the partial drill out from the opposite side before soldering. Obviously this is very tedious work, you'd only want to try this if you absolutely need to get a working board.

Lastly, manually drilling PCB material can create glass fiber dust which is quite unhealthy, so be sure to use a filter mask if you try this.

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If you have defined the holes correctly, then the fab should do a repeat run for free to correct their mistake, and they should do it expedited if you shout loud enough. However, this is not going to get you boards tomorrow.

Do you have a 2-layer, or more-layer board?

If you have a 2-layer board, then you can do a repair, as you have access to both top and bottom copper. Clean them of any solder resist round the hole, and pass a pin or wire through the hole, and solder top and bottom.

If you have a 4 or more layer board, and you need connections to the inner layers, then you are in much more trouble. There is no easy way to do this.

You might be very lucky and find that the inner layer connections come out somewhere else close by on the board, and you can link them there.

If not, there are products on the market called things like 'PTH repair kit', that claim to be able to plate the inside of holes. These are very difficult to use and get good results, especially if the board has been through a complete fab cycle. You will need to drill out the hole a little larger, to get access to clean copper on the inner layers.

How much larger depends what sort of mistake the fab made. If they built a non-pth hole, then inner copper will stop with a clearance back from the hole, and you need to expand the hole considerably to pick up the copper. If they built a pth hole, but didn't plate it for some reason, then the inner copper will meet the sides of the hole, and you only need to clean it by drilling slightly larger.

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  • \$\begingroup\$ It is a two layer board.Thank you for the suggestion and the repair is a temporary fix since its a protoype \$\endgroup\$ – ANONYMOUS Apr 25 '16 at 11:27

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