I was going to add this to the thickness planer thread. However, I think it merits its own post. Metal in wood has caused a lot of damage to tools since the development of our woodshop. Our members like to make use of used wood. This is commendable, however, used wood commonly contains metal. This can set off the SawStop, damage blades, and present a safety concern.
Now that we are building out a new woodshop. This is the time to address this. Andrew has been repairing the damage to the thickness planer and the jointer. It would be prudent to avoid it happening again. I believe this will be best addressed through education and culture change. Part of the problem is a lack of knowledge, the other is apathy. The latter is a lot harder to address, however, I think light is the best disinfectant and by educating all members about this problem we can hold each other accountable.
First the problem:
Metal in wood can be expelled from wood when it strikes the blade. This presents an obvious safety concern for the operator and everyone else in the room. Metal can also set off the SawStop, resulting in downtime and significant costs in replacing the cartridge and blade. Metal will also dull any kind of blade and especially impacts planer and jointer knives. This damage impacts all users after it occurs. This creates chip out, burning, and gouging. This impacts the enjoyment of the space for everyone. Metal in wood is not always obvious. Wood can self-heal to a degree. When it gets wet fibers close around nailholes making visual inspection less effective. Some fasteners such as brad nails and staples often hide very easily, especially in some wood and grain conditions. Staples are also common on new lumber, so no wood is truly safe.
Ok, some solutions:
I am going to look into getting a metal detector. I know they are fairly common for testing reclaimed wood. I will also work on increased signage about this problem. Ultimately we will need a woodshop 101 for all users, however, I don't think we currently have the capacity for this. And lastly, we all need to let one another and new users know about this problem. I would like to know what other solutions you may all have to prevent this.