BSARGE

I scanned a rib drawing and saved as a jpg. I then imported it into DeltaCad which I was going to trace. The rib is only about 4" long, when I use the measurement tool in DeltaCad it measures over 1ft long....It was scanned in at 100%, so I didn't enlarge it...does anyone know why this is?

thanks
-Bill

kbear

Not sure why it does this, but my cheap design software does this as well. What I do is measure it like you did, and scale it. yours measured 12" and you want 4". Divide 4 by 12 and you get .25. Scale it to .25. Might have something to do with the resolution of the jpg. file. Take the same file and save it with different dpi and then import them in to deltacad and see if thay all come out the same. Just some thoughts.

bkdavy

My Feedback: (1)

With deltacad, it imports the picture at the same size as the screen image, not the drawing scale. It takes a little math, but what I do is determine one of the actual dimensions of the scanned part (in your case the 4 inch length). Now import the graphic image. Make a measurement with the dimension tool of the critical lenght.

Example - Part is 4 inches long, Deltacad scale is set to 1.0000

Importing and measuring shows the part on the drawing measures 6 inches.

Erase the original import. Set the scale to 1.0000 x 4/6, that is (actual dimension divided by imported dimension)x(current scale setting). Now import the image again, and measure again. You should be exactly on (or at least verrrrrry close).

I do this all the time with engine images, servos, etc to get the correct parts layout with Deltacad.

Brad

Yuu

Great idea, bkdavey. My little deltacad only imports .bmp, so..... Anyways, to 'PRINT' a rib the size I want, I import the rib, and I measure the length of the rib using the 'dimension' feature. Say it dimensions at 2.54 ... but I want a 6" rib. 2.54 / 6 = .423. Then I 'select' the rib, I go to 'file' then 'set' and set the factor at .423, set to 'region selected', close. Then back to 'file' and select 'preview'. and up comes a picture...if it looks right on the 8-1/2 x 11 paper, then I print it. 6" on an 8-1/2" wide paper screen looks like 6 of the 8-1/2" wide sheet is filled with rib. After you print it, just measure it. If it's a little 'off', just change the 'factor' of .423 to, say, .43 or .41 and print and measure again.
But your method is for inserting the image to the correct scale to match the scale of the other things on that drawing. Thanks, I learned something today!!

patternwannabee

My Feedback: (1)

Hi Yuu,

Alternate method:

I always import bmps set at scale 1.000. Sometimes if you import at different scales, the image gets a little screwy.

After tracing the image, I'll measure the critical dimension, then SCALE (from the Select menu) the lines to achieve the critical dimension.

The math for the scale factor is:

SCfactor = (Desired dimension/Measured dimension)

Yuu

thanks, pattern, for that info! Now another question: When I import a bmp to the sheet, it shows up, but when I select, hit copy, and try to move the drawing to another location [so I can butcher it], it doesn't move. As I remember, I could do this previously, but can't do it now. Did I press the "mess this up" button by mistake, and now can't find the "correct this mess" button??

Yuu

Another question for you experts: For router cutting parts, you need to move the line of the part "half the diameter of the cutting tool" ... so, for 1/8" cutter, that's .0625"..... so here's my rib, and I want to 'offset' by .0625 ....... I can't find the way, and a guy told me how at a swap last month, but I can't remember. That's what you get for getting old, but it beats the alternative!!

patternwannabee

My Feedback: (1)

I think the "mess this up" button is an automatic feature in Delta Cad.

DC does not handle images well. For one, it only handles BMPs, and well, you saw what happens when importing images while set at a scale other than 1....

I have Delta Cad v4.0 (I know I should update). I can import an image of 2.7 meg, copy the image and paste it once. The second attempt at pasting fails. I have to save the file, exit Delta Cad, then re-enter, then I can do it a third, maybe a fourth time. At this point, the file size is getting rather large ~8 meg. All operations are slowing down, some operations don't complete, etc.

What I would do is retain only one image in the file. If you need to do multiple tracings on top of the image, use layers instead. You can turn layers on and off at will.

As to offsetting.... lines can be offset using the parallel line function.
Splines are done from the spline menu (this is for Delta Cad V6). I have done this before, and the tool works well, but I can't tell you where to find it since I have only V4.0.

Good luck.