Digital file from reverse engineering - can MM be used to scan a drawing?
 

About time to put the Mechmate to work on a long deferred personal project. I'm going to build an experimental airplane from a proven design. The plans are cad drawn....on paper, unfortunately. The designer offers a kit which he produces primarily on his...ahem much smaller...3 axis cnc router table. He's not inclined to offer digital cut files though there is nothing wrong with me producing them from a purchased set of plans. I have no intention to mass produce parts or otherwise violate the spirit of intellectual property.

Anyhow, quite a few of the parts are designed to be physically laid out directly from the drawings, transferring points with center punch and so forth. I'm not convinced there is enough detail on drawings for radiuses, offsets etc to layout to CAD. Thinking back over the crosshair laser setup that some have used I'm wondering if it would be feasible to essentially scan the drawing with the Mech, zero in on reference points, save them and produce a file. I'd appreciate it if anyone has recommendations on a software product which would enable this process.

The laser, which in this case could be a single dot style, would be mounted permanently on the car, to the side out of the way of the spindle. Wouldn't be needing to accurately locate parts with this method, I'd nest in VCP5.

Regards,

Chuck

Chuck, your local print shop might be able to scan those drawings for you. It was all the rage about 10 years ago when there was a wave of drawing offices converting all their paper drawings to digital and burning their drawing boards.

Gerald,

Now there's an idea, I'll call and see if any of these copy services can scan into some sort of vector file. Not sure how things would turn out working from a bitmap file. This would sure be the quick and simple solution, thanks.

Chuck

Even if they give you a .tif, .jpg, .pdf, etc, there are dozens of programs that will vectorize (trace) them.

HI,

Vector magic is one of the best and the online version is good for a try out!

http://vectormagic.com/home

RGDS
IRfan

CorelDraw works as well.

Appreciate the tips guys. In the back of my mind, though is the question...how do these conversion programs deal with things like line widths? Seems like if you have a picture with a heavy line drawn, how is this accurately vectorized into a drawing with infinitely thin lines?

Chuck

I doubt that you'll get results you'll be happy with. A wide line may become two lines, or just a single line. Depends on software settings for the conversion. I don't think you'll get a conversion that maintains line weights.

I personally have never seen a conversion I'd be happy with for a CAD drawing. My preference would be to redraw it from scratch, or if necessary, load a bitmap into a CAD program and trace.

Chuck, if you are tempted to go back to your original question, and use the MM as a scanner, I think you need to appreciate that you will have the same problem of finding the center of the blackness for a pure vector line. (....and also when to consider a vector as straight or curved, the exact point where multiple vectors meet, etc.)

Gerald, yes, it's the same issue now that you mention it. The process would be inaccurate.

I'm faced with the fact that in order to utilize this machine effectively I must invest the time and energy to achieve proficiency in CADD. Building the Mech was the easy part! Coming up with application ideas is no problem. Really learning digital design is where the heavy lifting comes in.

I suspect others have come to realize this also. I have little interest in carving interesting do-dads even though it is certainly an engaging process to watch as the Mech goes through its paces. Efficient manufacturing and production is the goal. I'm the weak link in the chain at this point.

Chuck

I agree 100 %. Even just using it for hobby purpose I came to the same conclusion once the machine was build. Driving the machine and feeding it with G code is the hard part. But now also the FUN part

Hi
Reverse ingeneere 3d files is the same thing ,it is easy one way not the other . converting a vector file to bitmap is easy but a bitmap to vector is lots of work . Stl files or obj for example are a mesh file like bitmap for 2d . Dwg dxf ige files are nurbs like vector files they are data, math formula describing the form in space ,that you can alter as you wish . Changing a nurb file to mesh is easy but a mesh file to a nurb one is lot of reverse engeneere work.
Normand

http://cao.etudes.ecp.fr/index.php?page=formats.htm
For some examples to see the difference