Sheet Metal Partial Walls?

I have a design intent problem, I have sheet metal formed as a ocotogon each octogon will have a tab bent inward but it will only be in the middile, say one wall in the octogon is 10 across we'll i want a wall say 4 inches in the middle bent inward which is fine if your goin to use a wall with a relief. here is my problem the tabs bent inward will not be flush with the top of the octogon, they will protrude up and over. yes i can use the the add wall flat and then add a bend to it but this defeats my design intent to control the length of the tab. lets say i make it 2 inches, i want to control this, usig the wall and bending it is great except if someone changes the radius the won't realize they threw the length of my tab off. what i did was used an extruded wall and created a datum point at the corner of three surfaces picking the green side of the wall, a datum goin thru the center of the octogon(datum right) and the top datum. i then sketched my wall with a arc and a straight line and dimesioned per my design intent from the created datum point to the end of the line and then created the thickness of the surface( the dotted white lines that represesnt the white side of the part) and dimeansion the dotted line to control the inside radius. it is my understanding i should control the sheet metal part with the inside radius dimensions. i then made the feature both sides 2 inches i now have a wall with my design intent (the length of the tab is contolled) rather the flat wall then bend technique. my questioin is this correct? i got excatly what i want but i have my doubts by driving the radius this way. all other sheet meatal feature seem to have an internal radius option driving the radius(you know ...with bend# thickness or 2x thickness and the cool round corners if you sketch with all straight lines) rather creating the inside radius and dimentioning it yourself. it works but am i right or wrong? any suggestion are appreciated

Yup, you did it the way I would have, not that means very much. Driving the radius that way is fine. The way I understand your explanation is that you used an extruded wall with radius, thats a clean way to do it.



Don't concern yourself too much about the white or green side of the part as the driving surface, you can use either one.



As far as the datum points they may not be necessary. I would have started the part with 2 datum planes intersecting along the center of the octogon and used that as a reference, added a center line and used an edge as another reference. This is assuming the tabs are centered on the wall. I am secong guessing, I am not sure of the details or intent.



jperkins