trying to split a mold

[evanp4509U4JZ]

I've done this before but I can't remember how. The part to be split and the splitting tools are labeled. Any help is appreciated.

[jhackney1972]

You have a great big hole in your cutting plane you want to use with the Split Body command.  You also have to create a surface on two planes to get it to split correctly at least the way I see it.

[evanp4509U4JZ]

I did a combine/cut first using the "mold part" as the tool. A section analysis shoedw that worked. Then I tried to split the remaining area with the split tools. It previewed like it worked. I clicked "OK" and it says "compute failed". In "more info" it says compute failed in a different font.

[davebYYPCU · Accepted solution]

Actually, it effectively has 7 holes in it.

You have patched the 6 bolt holes, but they are not part of the cutter.

But all is not lost, boundary fill a top block down to the combined shape, which did work.

Same for the underside.

PS - double check the bolt holes, I didn't see them for this side - which I see is correct, now.

Fix timeline errors when they occur with Undo.

Might help....

[evanp4509U4JZ]

I somehow did this in the past with split body. Any idea how? I thought I just patched the small end of the holes and selected the patches as tools for the split along with the large outer surface but that doesn't seem to be what will work.

[laughingcreek · Accepted solution]

your chasing your tail.  one of those errors in the time line (marked in yellow and red) is preventing you from doing this.  My preferred methods for making molds uses the boundary fill command.  this works on the bottom, but doesn't on the top half b/c of the errors in the time line.  here's a screen cast for the bottom half.

[davebYYPCU]

There are a few ways to do it.  You could split the block before the Combine Cut, with a side view sketch line.

Your geometry is pretty bad, (misalignment)

projecting the cutter, gives 2 lines.  so not quite square, so had to Project > Intersect, and join it up.

For Split body to work, the target must deliver at least two bodies after the successful split, 

in your case the cavity was working against you.

BTW my Boundary fill was only attempted on top, work without error.

[laughingcreek]

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@davebYYPCU wrote:

...BTW my Boundary fill was only attempted on top, work without error.

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when I did boundary fill and picked the cell for the top half I didn't get a system error, but the resulting body was for the cell on the bottom.  is that not what happened to you?

[davebYYPCU]

Nope, I sent my file up there, the boundary was my own, I didn't use his box.

[evanp4509U4JZ]

Ya, unfortunately most of these are pretty inbred, they get modified, used somewhere else, modified, used in another place. They have a very tall, skinny family tree. We are new to injection molding and as the understanding of draft angles and mold geometry changes so does the part. The problem area in the timeline is the result of fixing a fix to draft angle that produced an undercut that wasn't 3 axis machineable and would have created ejection problems. Live and learn.

Thank you both for the help.