Tracing hand-drawn designs

[DarkFlights]

Hi everyone,

I'm probably the least tech-savvy person ever to try and use this software, so please bear with me. I have some hand drawn designs that I need to get made into DXF or DWG files for laser cutting, they are 2D designs. I was recommended FreeCAD, but I'm not sure it will work. I currently have the designs scanned at a reasonably hi res (300dpi, but I can scan things at much higher if needed), in jpeg format. I also need them to be 1:1 scale, and they're not drawn at that size as it woul be a bit too small to hand draw the necessary details. So I need to be able to scale them down as well.
The reason I'm trying to do the conversion myself, rather than just send the designs as they are to the laser cutters, is because they will charge me £15 per design for file conversion, so I'm trying to keep costs down. With about a dozen designs, you can see how this all adds up!
The reason I don't do the laser utting myself is because they are going to be cut in steel and brass, hence why I won't be buying a machine at any time in the near future, in case anyone was wondering.

OS: Windows 7
Word size of OS: 32-bit
Word size of FreeCAD: 32-bit
Version: 0.17.13528 (Git)
Build type: Release
Branch: releases/FreeCAD-0-17
Hash: 5c3f7bf8ec51e2c7187789f7edba71a7aa82a88b
Python version: 2.7.14
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 7.2.0
Locale: English/UnitedKingdom (en_GB)

[NormandC]

Hello DarkFlights,

Welcome here. Your question is not stupid! It is actually a pretty complex matter. (EDIT: while I was writing it seems you or a moderator changed your topic subject from "Possibly very stupid question from total noob" to something more neutral while also more explicit - which will make it easier to search in the future, as this question regularly comes back)

There are basically two methods to get to the end result:

1. Import the jpg image in FreeCAD (or any other CAD program) and manually trace over using drawing/sketching tools.
2. Use an external software to automatically generate paths from the jpg image, clean up and export result as vector format.

Regarding point 1. FreeCAD is geared toward 3D modelling. It can create 2D geometries, but if all you're interested in is creating 2D DXF files, you don't necessarily have to do it in FreeCAD - a dedicated 2D CAD program like LibreCAD/QCad or DraftSight could do the job just as well. LibreCAD/QCad might be easier to grasp than FreeCAD, but you won't get as much help with those programs - their community forums are not as active as ours - not by a long shot!

For point 2, to my knowledge no free CAD program can do this. You can do it with Inkscape, a free vector graphics program that can export to DXF. So in theory, you could do the whole work in Inkscape; but scaling might be an issue, as it calculates object size with line widths. In CAD you can be very precise, and line widths are not taken into account. A workflow of starting with Inkscape then finishing up the drawing in CAD would be a possibility.

Going the automated route might save you time... Then again, it might not. It may depend on the quality of the scan, and if the thickness of your hand drawing is regular. Cleaning the scan first in a bitmap image editor like Gimp would be a good idea (reducing the scan to black and white with high contrast). The generated paths may be complex and have variable widths, which you won't want. So you might end up having to spend a lot of time cleaning the paths up. You may find that tracing manually ends up being quicker.

Since you have no prior CAD experience (nor image processing/vector graphics I presume), this may very well prove a lengthy process as you'll need to work with and learn one to three different programs. You may find that the £15 charge per design is actually cheap...

Are you willing to post one of your hand drawn designs? Do they describe geometric patterns, or more curvy designs? We could tell you more by having a look at one of them.

Cheers,

Normand

[DarkFlights]

Hi Normandc, thank you for your reply. I think it looks like I'll have to pay for the images to be made into CAD files then, as time is pressing. I currently can't upload anything, as I'm getting security messages and can currently only access the forums via an email link through my phone. The shapes are very organic.

[bejant]

I think it looks like I'll have to pay for the images to be made into CAD files then, as time is pressing. I currently can't upload anything, as I'm getting security messages

I think that the security problem is fixed now.
Tracing over an image entirely in FreeCAD usually isn't too difficult, so if you think that you might have a use for it in the future you may want to consider learning how to do it now, or before the next need occurs.

[manos]

Hello DarkFlights,

Hello NormandC.
Is your post still valid even after the advent of 0.19 etc.. ?
I mean is there any new solution except those two's ?
Thanks
manos

[chrisb]

Is your post still valid even after the advent of 0.19 etc.. ?

Normand is currently not active here. For tracing an image you can use Inkscape which creates an SVG, which then can be imported into FreeCAD.

[mario52]

Hi

Hello NormandC.
Is your post still valid even after the advent of 0.19 etc.. ?
I mean is there any new solution except those two's ?
Thanks
manos

just for my info which tool would you like ?

many info please

mario

[ragohix769]

Hello DarkFlights,

Hello NormandC.
Is your post still valid even after the advent of 0.19 etc.. ?
I mean is there any new solution except those two's ?
Thanks
manos

You can use DraftWB to retrace with polyline, over an image imported and right scaled with ImageWB. Now it works very very well, as snapping tools over objects now are working

[this is a general reply to this very old thread]

[chrisb]

Now it works very very well, as snapping tools over objects now are working

You cannot snap to lines on an imported image, can you?

[manos]

Chrisb thank you for your answer about inkscape. I will try it.

Mario52 and ragohix769 thank for your answers too.