You should give the option to the user to extend the solid infill area when it comes to parts that are in the middle of the print.
Sometimes when you have a 10% or less infill, the solid parts fail just because there is nothing there to support it. In this cases the only solution is to increase the infill density, while if there was an option to extend the solid infill area would have solved the problem.
Re: Solid infill area
Isn't the solution for this just to add more top solid layers?
Re: Solid infill area
i recently had a situation where this would have been helpful. it was basically a big block and in the center it had a large vertical hole which got tapped for threads. as joe said most of the strength comes from the hole being attached to the top and bottom layers but it really needed alot of perimeters set around the hole so that it would still be nice and thick after the threads were cut in. only option really was for me to apply alot of perimeters to the whole model. normally not a problem but because it was a large block that didnt need strength it turned out to be a major waste of time and plastic. its very rare that i would need a feature like this but it definitely would be nice for those instances
