Sheet Metal Bending - Workflow

mporter88

Hi. I am an inventor of sorts and have begun messing around with Sketchup (which I wish I had done years ago!).
Currently I am using 100/1000" aluminum sheet metal and have been using Sketchup to model and refine the components as I finish the prototyped parts.

My question is regarding how best to use sketchup to model "bent" sheet so that it will have the radius edge that bending on a break creates.

All of my bends are 90 degree and are square to the mating edges...meaning that basically I am attempting to model a rectangular box made on a sheet metal break.

I have been just defining a 100/1000ths edge rectangle and pulling it up to create a side wall which is dimensionally accurate but results in sharp edged angles.

I now see that there are some plug-ins that add a bending capability and thought to ask a question of you guys as to recommendations for which plug-in and what you would propose for a work-flow for doing what I need.

Any input would be appreciated.

Thanks very much.

mporter88

Jean Lemire

Hi Modelhead, hi folks.

You can simply use the Soften/Smooth function to make edge look roundish or you can actually use the "Follow me" tool to really round edges. However, for sharp bends, I would try the first approach since it presents two advantages:

1 - It is quickly done.

2 - It do not add any geometry to a model.

However, if you do find that you get better looking results with the "Follow me" Tool, try using as few segments as you can in the arcs that you will use to create the rounded edges. This will keep the number of edges and face low and you will save in file size. Of course, all that depends on how many bent sheets you have in your model. With only a few boxes, even using the default 12 segments for arcs will not present any problem.

Try searching the sites dedicated to SketchUp with words such as "box with rounded corners" or "rounded edges" or "rounded corners".

Just ideas.

mporter88

Thanks for the replies.

I am actually drawing dimensionally exact (to .000) horizontal base rectangles and then pulling them up 100/1000 so that the sheet metal has accurate thickness and my various contours, holes and tabs are accurately modeled in extreme closeup which is helping me to refine the design.
Then I notch the 4 corners of the base (100/1000 x 100/1000) to allow for the simulation of bent tabs.
Then finally I define a 100/1000 wide rectangle along each edge of the horizontal base rectangle (between the notches) and pull them up to create a side wall which is correct in everything except in the absence of the inside and outside radius curves that make up corners actually created by a sheet metal brake

Because the radius of the bends is integral to the way the parts interact I am hoping to find a way to
model the entire flat sheet and then make the various bends via one of the bend plug-ins such as freescale (by Fredo).

I suppose I will just install it and try it out.
If freescale allows for accurate bend allowances (shortening and bend radii depending upon tools and material) it could be a great addition.

Failing... that I will explore the "follow me" option which I have not so far figured out how to use to connect two surfaces, at angles, with a specific radius arc.

Thanks again...
Any input appreciated.

mporter88

Gaieus

Hi Mike,

I can imagine that FreeScale would work finely but there are also a couple of bevelling plugins that you could use. Jean is right that you should keep segment count as low as possible (although I guess these models won't be to complex eventually to create extremely high poly stuff).

If you could upload an example file we could have a closer look at the details (you don't have to upload your latest invention of course )

mporter88

Thanks for that Gaieus.
You are correct that the thing is not very complex in the scale of such things.
In my shop simplicity is king...and form follows function.

I will look at beveling plugins and will go ahead and download Freescale.
I will keep an eye on the segments count just to be aware.

Even after all these years...Learning how to do stuff makes me feel good.

Thanks to everyone for the input and...
Any further input is appreciated.

MP

Jean Lemire

Hi folks.

Keep in mind that using small dimensions will produce small facets and that SU cannot fill a face which has a side smaller that 1 mm or about 0.04 inch. Since you are talking about a thickness of 100/1000 I presume that you are talking about 0.100 inch. If this is the case, the bending will produce segments that will be smaller than the limit and you may experience facets not filling.

Do not despear. Draw everything larger than real size by a factor of 10 or even 100. The faces will close. When done, scale down accordingly. The faces will stay closed.

Just ideas.