is there a point at which the boolean modifier will stop working? im trying to perform what can only be described as an enormous intersect boolean operation and blender has not responded for about an hour now. im wondering, if i just leave it will it eventually perform the task. or has blender stopped working/ processing?

Its quite easy to overload that modifier and have something like this happen. Depending on your machine it might work it out, but you might as well restart blender and try something a little more simple. Modeling by hand will get you better results anyway.
theres the file. if you imagine that plane below it extruded up over the square tubes. all i want left is the lines inside the box. all the other lines i want cut off. now you can see why i dont really want to do this by hand :stuck_out_tongue:

Since I am having a simlar problem rather than make a new post I think this would be a good place to make some comments about my experience. I am trying to make the ten commandments tablets. I make a cube into a tablet using the bevel took and adding vertices to round the top and then add text to the scene and extrude and turen the text into an object but don’t do any bevels or make the text more complex as this creates more problems for the boolean action. I even tried un-subivide but that really messes up the text after they are turned into an object. Has anyone tired making a tombstone and cutting out the letters using the boolean modifier? I would like to see if this can be done and use some of the text effects like bevel? This topic has come up several times on this forum just from what little reading I have done it would be nice to see if there are some tricks to make the text work in a boolean operation so that you can carve different windows fonts into an object. And yes when I do get it to work it takes allot of time for it to do the boolean which is certainly understandable. I have a AMD Phenom II X 6 10SST with 8gb memory and it still takes time.

Use the knife tool. Cut generally around the shape to make it easier to work. Join the box to the lines. Then from the top view cut around the outside of the box snapping the knife to the corners of the box as you go.

hey everyone. thanks for the comments. ive tried the knife method but it only seems to cut the top of the box section. should i have ‘limit selection to visible’ turned off when i do that?
im not sure what you mean by ‘join the box to the lines’ do you mean extrude the box into the lines or am i totally off?

ok, ive managed to cut the number of verts down by a lot. a lot lot. and the boolean finishes. unfortunatly it now says that the boolean opperation cannot be performed?! whyyyyyy :frowning: any ideas why this might be happening?

can anyone perform the intersect boolean modifier on this file cause my puter doesnt seem to be able to handle it. ive cut down the vertices, made the normals consistent, and removed the doubles. so its gone from 248039 verts to 12140

ok. im going for the knife technique. i have a problem though. the first one is that the knife tool doesnt seem to want to cut faces properly that are on top of each other. the second problem is very strange indeed. when i use the C select tool to select edges it frequently selects an edge thats miles away. im not sure if this is the code thats generated the tubes or what but has anyone come across this problem before?