Partial Corner Round-Over?

[AndrewRaastad]

I know that the "Follow-Me" tool allows you to round over an edge all the way around a surface... like the edge of a table, or around a circular surface. But what I would like to know is how to "round-over" a corner but only part way along that edge?

For example, take a 4'x4' that is 2' long. Now, make a mark 6" from either end on one edge, and then imagine taking your Router with a 1/2" round-over bit from one mark to the other. The ends of the 4x4 would still be square, with a rounded edge in the middle. But more so, the round-over smoothly transitions from the square to the round-over then back to the square again.

How do you draw this in Sketchup?

-- Andrew

[AMarshall]

There are a couple tips I can give you. The first tip is that there are two modes for using the Follow-Me tool. With the first, you grab the profile you are trying to use and drag it around the perimeter of your surface - this can get tricky if there are a lot of twists and turns. The second mode is more useful I think. With the second mode, you pre-select the path that you want to folow and then click on the profile surface as the last step. This way, you could have a path that is a maze, as long as the lines are all TRULY connected and you pick them in sequence. So using method number two, you could make a line in SketchUp 6 inches from the end of your 4x4 - each one going out perpendicular to the edge. Almost like using a square to draw a line across the leg at 6" down. This will break the long leg edge into separate segments so that you can start & stop at the spots you want.

This helps with the start & stop issue, but doesn't really help make a smooth transition. This is where the second tip comes in. Since the Follow-me tool traces along a path, you've got to give it a path that echoes the gradual fade of the roundover. What you will want is a quarter circle going out into "space" starting at the endpoints of your main path line segment. This quarter circle should be rotated 45 degrees from the face of the 4x4 so that it hits each surface the same. For the radius use the same dimension as the roundover, or you could experiment with larger numbers to get a more gradual fade.

Let me know if you need more help - this may be clear as mud!

[PurpLev]

If you mean something like this:

I am sure there are numerous ways to go about it. The way I did this was draw the path on top of the part that the "router will follow", then drew the "roundover bit" arc on the front of the part. using the selection tool, selected JUST the path you want the roundover to follow (2 straight end lines, 2 arcs, and 1 long straight stretch between arcs), then select the follow-me tool, and click on the round over shape you want to route the part with. then remove unnecessary geometry that may be left over.

2 tips that might make/break this though:

1. the follow-me round over shape needs to be an enclosed face so I actually drew a 1/2"x1/2" rectangle, drew the arc between 2 opposing corner to have an arced face so to speak:

2. SketchUp does not like to generate curved surfaces in small scale. So before doing the follow-me procedure scale up the model by 100 or so, do the follow-me process, and scale the model back down by the same amount to get back to your original dimensions.

[AndrewRaastad]

I am sure there are numerous ways to go about it. The way I did this was draw the path on top of the part that the "router will follow", then drew the "roundover bit" arc on the front of the part. using the selection tool, selected JUST the path you want the roundover to follow (2 straight end lines, 2 arcs, and 1 long straight stretch between arcs), then select the follow-me tool, and click on the round over shape you want to route the part with. then remove unnecessary geometry that may be left over.

Thanks for attempting to give me step by step instructions on this, but.... feel bad saying this, but you demonstrated the exact opposite of what I would like to do. Maybe my terminology is wrong? When I say "round-over" I mean that two surfaces that are 90° to each other are joined by an outward curve. You can run your hand along one surface and then curve over onto the other one. When I made a cutting board for my wife (thanks again Marc for that video!) I rounded over the edges using a router, but I did it all the way around all four edges so there were no sharp corners.

What I am trying to draw in SketchUp is if I *didn't* go all the way around all four edges. Or, as in my example, using a 4x4 board, start some distance in from the end and round over the edge to some point an equal distance from the other end. I don't want to make it look like I "turned" the 4x4, but rather just rounded over the edge to remove the sharp corners along the edge.

While it might take longer to describe this, as well as draw it in SketchUp than to just pull out the router and hit it, I want to add this detail to my drawing so I can play with the length of the round-over before cutting wood so I can see what looks good and what doesn't. Would one long round over look good, or two shorter ones along the same edge? If like in the case of a cutting board, where would I want to do a round-over for finger holds, how long should they be, etc.

Again, thanks for the help so far, and I apologize if I was not explaining things correctly.

-- Andrew

[PurpLev]

My bad! I didn't read it right (read it left).

You can do something similar to the technique I had previously mentioned but just with the follow-me profile in the other direction. however, that said, let me show you another method you can use - personally I think this one provides better results as well.

The following method is actually rather woodworker-in-mind based. you will be making a router-bit so to speak, and then put that bit to use on the part you are rounding over.

1. create your 'router bit'. this is a rectangle - as long as the part/section you are trying to round over. height of the 'bit' does not matter as long as it's taller than the profile you are trying to put on your 'board'. you'll notice that I also rounded the rectangle 'bit' so that it will ease the transition into the rounded over edge. Put your (inverted) round over profile on the edge:

and use the follow-me tool on the bottom face to generate that profile all around it. you now have the equivalent to a round over bit:

NOTE: Make that a component so that it won't 'stick' to anything else later on plus you can always go back and use it to round over your other parts (you can resize the 'bit' to shorten/elongate/englarge the profile)

TIP: you can copy that component, and put it in it's own separate model file that you can then import into your other models to use to round over parts.

2. Place the round-over 'bit' adjacent to your board in the appropriate location you want rounded over:

Select your 'board' and your 'bit' and click Edit->Intersect (Faces)->Selected (this will generate the frame lines for the round over shape)

3. select your 'bit' and click Edit->Explode. (this is required in order to add the additional faces of the rounded over shape)

4. Remove all extra geometry (faces and lines) - careful not to remove required lines or you'll have holes or missing faces. and you get this:

Hope this helps.

[bfblack66]

I hope this thread has not gone cold. I tried starting with what I thought was something very similar to your 1st figure, selected the bottom face to define the path, selected the "follow me" tool and then the roundover profile. While my result looks similar to your 2nd figure, when i orbit around the 2nd figure, the results looked weird. Is there any way to include your sketchup file that created the two figures?

 

Thanks