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Tough rounds problem

altair

New member
Attached is a snapshot of a part I need to put rounds, or something else, in the corners of the tube intersections. The tubes are 1.75 except one is 1.50. This part has eight tubes and I have a number of these "sea urchins" to model none more than eight and some with less.


I have tried several tecniques including all concave etc, tried in different orders, tried one at a time, a few at a time and all in one set all to no avail. Have increased part accuracy and am now out of ideas.


Any help would be appreciated.


John


View attachment 2530
 
Rounds like welds? or... I think the only way you are going
to create transitions between that joint is to use surfaces.
 
did you try to "add" new round point in one round (one feature)? You can do this by clicking on corner or edge and than add new one or more.Than define some round smaller and some bigger... this is useful from few reasones..If are rounded surfaces crossed under many angles and many small or even very big rounds (in one edge or corner) than you can use this function for adding new round because sometime are CAD systems not able to create some kind of complex geometry for "first try" sometime it is not so easy because all models (or most of them) are demonstrable by mathematical computations and this is reason why it is sometime pretty hard to create something complex although it can look like pretty easy stuff...
You can also try to play with partial definition (references) of rounds by detail properties from round menu..Or just try to do this by surfaces and than merge(trim) it .. this can help you as well..
hope this help...good luck..
 
Sometimes it is best to "create rounds as you go. This means to create two of the tubes, then out in a round. Create the third tube, and a round, and so on. This makes the rounding easier to do. Sometimes this works, sometimes it doesn't, but it is worth a try. You probably have patterned your tubes. In order to do this, you will have to delete the pattern and create the tubes individually.
 
Try picking the edges from the smallest through to the largest.

View attachment 2532

Also if the rounds get too large with respect to the shortest edge you will have problems. In this particular configuration with 44,45 and 38,1 mm tubes, the largest round I could get away with was about 4mm.


Default accuracy was left unchanged. Rounds were created at R2 as a single feature but in stages to check it was going to regenerate. (I managed to get them all in with no failures until I started increasing the radius above R4)




DB

Edited by: Dell_Boy
 
Thanks all for the help. Our data police disslike rounds early in the part but they may have to just live with it.


I had one person in our company able to get a .45 round all over in one set, no transitions just picked all the intersections. I was able to open it but once I changed the size down (regenerated fine) to .3r and then back to .45 it failed. The largest I was able to get is .3 without failing. I am now able to get .3 on my own but cannot get to .45. I even tried "all concave" option suppressing the revolves.


Why would one guy get it with the same build version (one company and all) and I cannot? Makes no sense to me.


Also getting the real small radii is now not creating problems.


BTW my radius will be changing as it will be a negotiated number with the machine shopand tooling considerations.


For the person that asked my to post the file, that is difficult with our security concerns. Wish I could but it aint worth my job or jail time. LOL


Thanks all
 
John,


Could you create a spherical object at the center of your urchin and connect the rounds to the sphere?
 

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