Hi it's me again, and I have a new one. I'm doing some duct work and I've got a request that is stumping me. I've done round to square before and it's simple however this one is on a radius. It goes from a 14" O.D. pipe to a 10.36" x 6.36" O.D. Square. Typically I'd try to do the square to round straight and then radius, but the cad drawing they sent me doesn't leave much room for that! I've considered doing it in segments with smaller ones towards the square and getting larger towards the circle to account for the tighter radius, but solidworks can't seem to understand what I'm doing with sheetmetal and if I do get a simple extrude to work I'm not able to flatten it. Any suggestions?
Hi Ambroas, I am unsure why you are mentioning "sheet metal" - because you are not going to do that with Solidworks in sheetmetal. You can however do it as a loft and what you need to do is use two guide curves to do the loft. See picture below. Hope this helps.
Mentioning sheet metal because I have to create plasma files for the piece to be cut, and break lines for it to be bent to be made. I'll be making it out of 11GA (0.125") mild steel. I did try a sheet metal loft though but had no luck
Hi Ambroas, If you use a press brake to do the "folds" - then you will end up with straight lines. Therefore, you could approximate the bell mouth by making a series of 2" "cone type sections" - and welding them up - but that is a lot of welding (and a lot of scope for distortion) - and it is an approximation to the curve that you have depicted in your left hand side view (in your picture above) - which may be reasonable. If you do it this way - then you will be able to use Solidworks loft in sheet metal - but not with the curves - because it is not practically possible to make it with a press brake - which is what the Solidworks loft is assuming. If you have a look at the video below - you will get my idea. https://www.youtube.com/watch?v=FZ8CGGYamuE Hope this helps.
That loft shown above is a compound curve that cannot be flattened. If you want to make it from sheet stock, the easiest way is to make the duct bend in the rectangular x-section and then transition to the round. That way you can make it in SW SM and it will flatten. You could even transition from a rectangle to a square intermediate x-section during the bend to smooth the transition. AceEngineer
You can gain space by first reducing the round to the right surface. Based on a sheet thickness of 0.125", the O.D. would be 9.12".
Just reading the last two comments above - I don't think this is what Ambroas is looking for - see picture 1 below - but maybe I am mistaken? Instead what I think Ambroas is looking for is the curved shape - which as I said previously - can only be made as "conical type" segments - which when welded together gives the curved transition from rectangle to round sections - see picture 2. Picture 1 Picture 2 ]
Go back to the designer and have him change his design. Explain to him for manufacturability and cost the design should change. Bring couple of designs you can work with
How about submerging the round to rectangular transition *inside* the large round section then do the bend in a constant rectangular section in the space available in the sketch?
Ambroas, were you ever able to come up with a solution that met all the design requirements? What did you end up doing?
