Metal flanges - flange on a flange on a flange collision issues

m_min

https://cad.onshape.com/documents/4957895a9276b9c9b89f0a7d/w/f29b960e9538ded42da7d955/e/4e4a97c965304d46ad1d7d39

Hello,

I am having trouble with the flanges of a metal box right now. I need to design a waterproof (resistant) box that will house a cooking gas canister accessible from the outside of a vehicle. Looking online i see that a lot of designs flange the wall metal towards the door opening hole and then have another flange pointed outwards and 90 deg on the interior of this flange so that a foam strip can be glued into the door and the flange provides a decent seal as it presses into the door.

The issue seems to be with "shortening" flanges to prevent collisions. I got around this on the first round of flanges by using the thicken tool to reduce their size. On the flange on the flange it seems to not let me construct this due to collisions with the other flanges. I suppressed the previous ones to select the appropriate areas to shorten, but upon unsuppressing them i get errors again.


perhaps i am approaching this in a poor manner? I thought to reorder the flange and thicken (shorten) operations but it seemed to cause further problems.

Any advice is greatly appreciated

shawn_crocker

@m_min
I know what you mean with the awkwardness of flanges trying to collide and automatically push and pull each other around.  check this doc. GasLocker - open - Copy | Part Studio 1 (onshape.com)

and this .gif



My suggestion always seems to come back to this when aiding in sheet metal problems.  do everything you can to design the whole shape as a solid even if it means rolling back to add in some more solid modeling features.  onshape behaves much better when you supply the sheet metal feature with all the geometry required to make the part or group of parts.  I work for a company that makes a lot of compartment products designed just like what you are doing.  I usually set aside a minute before actually using the flange feature because I so often find myself regretting that I didn't just add in the extra geometry to the base solid.

shawn_crocker

I usually start off creating the initial extrude to be the size of the entire outer envelope of the compartment.  Then, often I will create the door first by splitting off some of the front geometry.  this way I can reference the completed door to push pull and cut away the other parts of the body envelope to be sure everything is spaced away from the door itself.

shawn_crocker

@m_min
I know what you mean with the awkwardness of flanges trying to collide and automatically push and pull each other around.  check this doc. GasLocker - open - Copy | Part Studio 1 (onshape.com)

and this .gif



My suggestion always seems to come back to this when aiding in sheet metal problems.  do everything you can to design the whole shape as a solid even if it means rolling back to add in some more solid modeling features.  onshape behaves much better when you supply the sheet metal feature with all the geometry required to make the part or group of parts.  I work for a company that makes a lot of compartment products designed just like what you are doing.  I usually set aside a minute before actually using the flange feature because I so often find myself regretting that I didn't just add in the extra geometry to the base solid.

m_min

Ahhhh that makes a lot of sense. It's always funny how obvious an answer can seem after you hear it for the first time. Thanks for the explanation and wonderful illustrative gif!

m_min

@shawn_crocker Do you have any tips for the door? How do you usually take into account tolerences or "gaps" to make things like the hinge? 

Thanks again!

shawn_crocker

I usually start off creating the initial extrude to be the size of the entire outer envelope of the compartment.  Then, often I will create the door first by splitting off some of the front geometry.  this way I can reference the completed door to push pull and cut away the other parts of the body envelope to be sure everything is spaced away from the door itself.

m_min

great, thank you for taking the time to give some tips!