Question: Are you aware of any time studies or standards that have been developed to determine the amount of time it should take to create a solder joint while hand soldering, either a through-hole, or surface mount component?
Answer: This is always an interesting topic, time studies to determine how long it takes to create a solder joint. Lots of things are involved and I’ve attached some web addresses which will help with the background, but basically this is an industrial engineering application and is based upon the motions of movement and reach of the operator, the ergonomics of the workstation, the accuracy of placement and the fatigue and delay times associated with each task. So take a look at the following data and presentations on the subject.
Powerpoint Presentations (to download):
As you view these sites, there are also some areas where you can purchase the standards, but remember you’re going to have to be the one, who analyzes the movement to develop the individual time.
Now, using this type of information at one particular company, we figured on one to three seconds to make a solder joint. This included getting the solder iron from the holder, wiping it on the sponge, applying solder to create the solder bridge, contacting and heating the solder joint, then applying the solder to complete the creation of the joint. Subsequently the time to clean the joint also has to be included in this time, but the operators can clean more than one joint at a time so you have to figure an average time to do so many solder joints.
So if you use three seconds per joint that 20 joints per minute, 1200 joints per hour, etc. and since they are manually created, there can be lots of variation between operators creating those solder joints, which is why the process get automated. Automating the process, increases consistency of the solder joint and reduces many of the variables involved in creating the solder joint.
Another element that was used was, actual average times, which meant monitoring how long it takes to solder a given quantity of solder joints, which should include rest breaks, paperwork documentation, hygiene breaks and all other incidentals the operator does during the soldering operations. Divide the amount of solder joints into the time it took to make all those joints and you have the actual average time. For example if you made 100 joints and it took 20 minutes, then the actual average time would be 12 seconds per joint.