But there are other cluse, such as a bearing type being known from the parts list - you immediately know the bore and shaft dimensions, and they can be used as calibration points in a useful small program called "Screnn Calipers" from Iconico. The only releiable source of dimensions we have is to measure parts as they are stripped. But aside from dimensional info, which would be great, the section drawings could be vastly improved and made much easier to view and interpret. There are several good sectional drawings, and from my experience so far, they seem to be mostly to scale. In this case, the source images I'm referring to are the section diagrams in the Beaver parts manual. Otherwise, you need several photos from different angles and ideally a known calibrated camera. I've looked at photgrammetry a bit over the years, and it can be done from a single unknown camera, but only if you have some markers at known coordinates. > rather you have to translate the photo into >sensible CAD dimensions > rather you have to translate the photo into sensible CAD dimensions ![]() > So you can't do a straight tracing and automatically get good results, Many thanks all, I'll have a look at that software. Thanks for pointing out the free version is still available Sorry about that, I gave everyone a bum steer! I thought Ribbonsoft had killed the Community Edition and didn't check the small print properly. Alternatively, you can choose to remove the trial and use the free QCAD Community Edition instead. You can order QCAD Professional from our Online Shop and download the full version immediately. The trial runs 15min at a time and can then be restarted. These packages contain QCAD, bundled with a free trial of QCAD Professional. I have just refreshed my "QCAD" QCAD 3.21.1 (The free version is no longer available. You'll struggle to correct the perspective etc on a photo of a large machine, so I'd give that step a miss. Like Dave, I make sketches with accurate dimensions then go straight to CAD. Of course, you might then go the extra mile and extrude etc the sketches to create full 3D models. If you are going to bother drawing it up, you'll probably want to enter the correct dimensions based on actual measurements once you've got the shapes right. You don't need layers as such, as you can simply turn object visibility on and off or even delete the sketch when finished and save as another version. Most CAD programs will allow you to import a scanned image and manipulate it (scale, opacity, colour, position etc), then create a 2D sketch on top. I use qcad for 2D and Fusion360 for 3D.Īs LibreCAD is free, give it a try and see how you get on. For what it's worth, my preferred approach to this sort of job is to make a rough pencil drawing labelled with accurately measured dimensions and then use the dimensions to create a CAD drawing. Accuracy may not matter if you only want a cleaned up line drawing, but it's more work if you need accurate engineering drawings. ![]() ![]() So you can't do a straight tracing and automatically get good results, rather you have to translate the photo into sensible CAD dimensions using the image as a guide. A CAD package is the exact opposite - everything is specified precisely the drawings are entirely informative. They're just a good looking unreliable blob no dimensional information plus lens distortions. What makes tracing tricky is that photographs measure nothing and don't understand scale. Any number of layers can be added if that helps, for example to hold construction lines or text. Then create Layer 1, and trace lines over the photographic image. The tracing technique is easy enough: take a photo and import it into Layer 0. (The free version is no longer available but there is an effective free fork called Librecad if you're on a budget.)īoth support layers (ie multiple transparent sheets stacked on top of each other that can be made visible or not) and a layer can be an image (photograph) or a CAD line drawing. Scaling would be useful, as would snap to a settable imperial or metric grid.Īnybody know of such a program?. At least you could end up with a drawing with fine, staright lines and maybe remove some ambiguities at the same time. Does anybody know of a software package that can import a photo/scan, show it faint in the background and let you construct lines, circles, arcs etc over the top of it but as a separately saveable drawing file?. I would dearly love to make some better drawings for this mill, particularly the head, leadscrews and gearboxes. ![]() If it is angular contact then I just don't understand how it is supported and takes load. I'm pretty sure my top third bearing was a standard deep groove too. It's annoying that there is so little documentation on the many variants.
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