how to keep through hole components correctly oriented when soldering?

[matrixofdynamism]

When soldering through hole components, since the board is unside down, it often causes the component to disorient.

Basically, one would orient the component correctly, then solder it with the board tilted or upside down. To keep the component in place, one may even use paper tape. However, it often happens that one side of the component is much closer to the PCB surface than the other.

For example, when soldering a through hole 1/4W resistor, one of the sides gets soldered while being significantly closer to the PCB than the other. This is a very annoying problem.

What practices/solutions exist to mitigate this? Should I simply never try to pull the pin of the component as I solder it since even with tape, due to gravity or push from the soldering iron, with the board upside down, the component may go slightly out of place.

 

[d123]

Hi,

Annoying, isn't it?

I don't think it's necessary to pull any pins while soldering through-hole, bent at 45º, and just touching the pin and pad with the iron while delicately applying the solder should help to mitigate movement of the component.

A laborious (and I can't be bothered doing this anymore for those nice, neat regimental topsides of a through-hole pcb that only I will see) method is to make toothpick/flat wooden kekab sticks, etc, moulds to fit the shape and top of the component, it's surprisingly effective, but time-consuming, then with masking tape stick it to the board, away from the point where you are soldering. Paper (masking) tape alone can come loose with the pressure applied on the other side, unless you make a thick pad of the stuff and really press the sticky bits down with a little overlap on the soldering side to provide "strain relief".

45º bending, making use of gravity, (checking after each solder point to straighen up any changes), and mainly delicacy seem important?

 

[KlausST]

Hi,

With automated THM soldering the PCB isn´t upside down. Only with hand soldering.

One solution is to do it like a car service station: They lift the car and work from below... Do the same with a PCB ;-)

No, just a joke.

There are soldering aids: like this one: **broken link removed**

You assemble the components from comonent side, then you place the cover and the foam keeps the comonents in place.
Then turn the whole frame 180° and solder the components from solder side.

Klaus

 

[c_mitra]

Soldering is an art; you need to devote time and effort for good hand soldering. It will be worth the effort.

Please place big components first, bend the legs so that they stay in place, solder one leg only at a time, check and recheck (believe me, it is easy to make mistakes) and finally solder the items.

If you have SMD and legged components, you must be far more careful. But it can be done and it takes time for a good job well done.

 

[ads-ee]

I remember back in the days of DIP packages when I worked my first job, the technician that we had would perform a sequence like:

repeat {stuff-solder} end

The soldering would just be the something like the power ground pins (corner pins on the diagonal). They would keep the part flush with the board during soldering by setting the back edge of the board on this piece of anti-static foam and the component position supported by another piece of foam that had a peak in the center. With a light touch of the soldering iron nothing moved (they would put something heavy-ish on the PCB like a heatsink if things were too wobbly).

Once they soldered all these corner pins it was really easy to finish the board up at any angle (nothing will move at that point).