Scan a custom molding profile into sketchup


#1

I’m modeling a home with custom moldings, and want to a) replicate the molding profile and use follow-me to place the moldings along bases, jambs, etc., and b) rotate the curve around an axis to produce a base mold for the outside corners of walls. I think my main problem is scanning the curve accurately into Sketchup 2017. Any suggestions?


#2

What have you got to start with? A sample of the molding?

Assuming you have the molding as a real life example, you could take a thin slice off the end of it and scane that to create an image. Import the image into SketchUp with Use as image selected. Then you can trace it with the various drawing tools available to you.

Alternatively, you could layout the shape of the molding by hand after taking measurements off the actual molding.


#3

Here’s another idea, assuming your mouldings are fixed and you don’t want to disturb them.

Find an external corner and take a picture as close as you can get and as near to straight on as possible. Import the image into SU and use it to trace an outline. Never tried it but it might work. And you can always double check dimensions against the real thing as you go.


#4

@DaveR’s suggestion if probably first choice if possible. If the molding is installed and you don’t have a sample, either use one of those pin tools to copy molding profiles so you can trace it and scan it in, or what @simoncbevans suggests. I posted an example of the latter in another thread here.


#5

I have professional experience with mouldings. I used the method described by @DaveR. I downloaded a profile brochure from the supplier (pdf) and imported an image into SU to trace over.

It can be a little difficult if you don’t have drawing/drafting experience - it may help to work at a very large scale and shrink it down when you have completed tracing the profile.

I also work with a very useful extension called Profile builder (I recommend checking it out) - I think you would need SU Pro to use that?


#6

Thanks to all. I do have a loose piece of molding I can scan and trace, and will try scanning or taking a photo and enlarging before importing and tracing. Something will work…


#7

The scan will be the best option if you can do it. Don’t worry about getting the image sized properly to start with. Just import it and make it reasonably large enough to work with. Once you’ve traced out the profile, you can resize the model with the Tape Measure tool to make the molding the right size.


#8

Got it scanned OK, tracing is a lot harder than it looks…


#9

Maybe you could share the image and I could give you some tips.


#10

Deal. Base mold.skp (201.5 KB)


#11

Can you share the original image? And what’s the overall height of the molding?


#12

Yup.

Overall height is 3.307", thickness at base is 0.572, but it was painted, so I think the wood is really 3 1/4" and 5/8".

I tried using the freehand drawing tool, but my shaky mouse-hand was a little too free. Maybe I can desensitize the mouse somehow.


#13

I would recommend sticking to lines and arcs. Freehand is going to make this into far too many segments.


#14

Agreed. I’ve got the 7 straight lines pretty-well nailed. ARCs will take a while.

Actually, not too bad. I’ve got something usable after a few tries. Need to get a better image of the profile to do any better, but I’m on the right track.

Thanks to all.


#15

I agree with Aaron. Freehand won’t be terribly useful for this.

Here’s how I’d approach it. I started by editing the image to give it a bit more contrast and make it easier to see what is molding and what isn’t.

Then I inserted it into SketchUp as an image. Since this appears to be a base molding, I stood the image up on the red/blue plane so the resulting profile is already vertical when it is finished. Since the molding isn’t perfectly aligned with the edges of the image, I set in a vertical guideline and rotate the image so the back edge is aligned with the guide.

Then trace the edges with the Line tool. I temporarily changed the Profile thickness to 3 and the color to red so it’s easier to see. When the loop is closed with coplanar edges, a face will form. Here I switched to wireframe so you can see the image behind the drawn edges. To draw the ogee portion of the profile, I used the Classic Bezier tool from Fredo’s Bezier Spline extension. I also omitted the recess on the back of the molding since it isn’t likely to be seen and thus wouldn’t add anything to the model. Adding the recess in would be easy enough but you’d want to consider the benefit if there is one.

And that’s all there is to it. The profile would be ready to use.


#16

Wow. I was getting there, but this helps a lot. Many thanks.


#17

The problem with taking pictures/using cutoffs from demolished parts is that the original profile is likely worn out by sanding /painting etc. and not equally around the house as well.
In renovation projects that I have done, we usually take that in account and prefer the original moldings
(Straight edges)


#18

I do have some original moldings as well, so I’ll use them for the final process. I was using Sketchup initially just to illustrate to my wood-turning friend what I was wanting to do. Now I’m trying to figure out why Sketchup divides my molding into two pieces during the extrude…

Base mold - post-extrude.skp (309.9 KB)
Base mold - pre-extrude.skp (154.6 KB)


#19

You’re running into the tiny face issue. Those edge segments on that part of the ogee curve are too short. Use the Dave Method to get around that.


#20

Amazing; color me awestruck. Thanks again.