More of a drafting and scaling question then a vw question

[MattG]

Sorry this is more of a general drafting question but curious for a answer. I draft in imperial units 90% of the time. I am working on a install and it is in another country. The are a metric system country. The drawings I have to go off of for this are hand drawn in metric

1:40 and other scales. I mostly work in architectural scales so the 1:40 is something that I don't deal with often and just as important I never deal with in metric units. I am trying to take these hand drawing and build a cad file off them. Anyone have any thought as to what would be a good way to go about this considering I do not have and cannot find a metric engineering scale rule around my area at the time being.

Matt

[Ray Libby]

I would have my units set to mm, scale the hand drawing in inches, then enter lengths in inches on the drawing, rounding it to whole mm as I go. For instance, if I scale an object to be 44", I would draw a line and tab to the length field and enter 44". The line in the OIP will read 1117.6mm and I would edit the line in the OIP to be 1118mm or whatever you want your tolerance to be.

[MattG]

Interesting that's why I ask you guys

[Ray Libby]

Or have a feet/inches/metric calculator. I use mine to convert inches to metric to order cabinet doors as their machinery is metric.

[bcd]

You could draw and print your own scale rule - printing / plotting on high quality paper will allow you to make finer measurements.

OR.

Scan the hand drawing and just Modify>Scale Objects : Symmetric by Distance. Set your snap distance, move the scan to position and use as a tracing background.

[CipesDesign]

A metric scale should be an easy item to procure. If I was doing this job one of my assumptions would be that the folks on the receiving end will be used to certain (metric) standards and as such I would be trying hard to conform to them...

[Bob Holtzmann]

A good simple rule of thumb for metric scales compared to imperial.

A 1/8" imperial scale has a paper scale value of 1/96.

A 1:100 metric scale has a paper scale value of 1/100. You can see these values in Vw on the layer scale dialog box.

So, for the purpose of sheet layouts, 1/8" and 1:100 scales are approximately similar in layout size.

My plastic metric scale does not have 1:40. It has full scale 1:1, along with 1:2, 1:5, 1:25, 1:33?1/3, and 1:75. Smaller scales can be used by adding a zero (1:20, 1:50, etc.)

It could be that your drawings are in engineering imperial, which does have 40, for 1" = 40'. Engineering imperial scales are 10, 20, 30, 40, 50, 60.

[i did notice that the Vw layer edit's scale dialog does have a metric 1:4 scale option, which could be modified to make a 1:40 scale].

Edited July 21, 2010 by Bob-H

[Jim Smith]

I go back and forth between the systems all the time, & VW makes this very easy to do.

Say your drawing template is set to imperial 1/4" scale & you want to use this for your output but have a sketch with dim's called out in Metric. Continue with your normal drawing template, when you input values from the sketch just (eg 3655) just type this value into your OBJECT INFO PALLET but be sure to add mm at the end (ie 3655mm) and VW will do the math for you. Your drawing will be in imperial, but the values will have been converted. This also works if the values were noted as decimal Meters (eg 3.655) just type a M after this value (ie 3.655M).

This also works in reverse if you have opened a 1:50 Metric drawing, one can add either 30" or (2' 6") to a Metric item & VW does the math.

I keep a custom DIMENSION that has both Imperial & Metric values. This may be helpful to a client unfamiliar with either system.

Many of our drawings are produced in Metric but we sometimes have contractors who want a set in Imperial. For this I just duplicate the Sheet Views & Viewports required, note them as imperial, change the scale of the viewports to an Imperial scale requested. The Units are changed temporarily until the set is printed - I never save an imperial set but I do keep the Imperial Sheet Views incase they need to be updated/reprinted.

[Kim]

Am I missing something? Why not do the drawings at 1:1 on a design layer using the dimensions from the drawings you have, make sure all your 'precision' preferences are set to max. Then set the sheet layers up with viewports to create the drawings you need at the precision and format you need.

[Peter Eichel]

Kim, I couldn't agree more except Matt doesn't state whether the hand drawings are dimensioned or not. If their not dimensioned, he needs a metric scale ruler and to review the chapter about scale in his drafting text book(s).

At any rate, all drawings, whether hand drawn or not should be dimensioned.

[modpod77]

Kim, I couldn't agree more except Matt doesn't state whether the hand drawings are dimensioned or not. If their not dimensioned, he needs a metric scale ruler and to review the chapter about scale in his drafting text book(s).

At any rate, all drawings, whether hand drawn or not should be dimensioned.

i agree with you, Peter.

[Kim]

Another trick from the 'dirty deeds done cheap' department when I get a poorly dimensioned drawing, or sketch as I refer to them, is to scan the drawing, import it into VW as an image. Draw a line to a length you can determine on the drawing. Now it's just a matter of resizing the image until the known length on the drawing is as close as necessary to the line length. This may take several zooms, repositioning's and attempts to get it just right. And make sure you hold the shift key down while doing this resizing! Now create another layer and draw over the top as you would normally. Saves all the thinking, I make mistakes when I think ...

[Pat Stanford]

A less trial and error way to do it to use a dimension object. Best done in the new blank drawing.

Find an object in the drawing of a known length and put a dimension object on it.

Go to the Scale menu command and put in the real dimension divided by the measured dimension. These numbers need to be in decimal units (feet, inches or metric), Feet and inches won't work as the calculation won't work properly.

If the scale does not match exactly, repeat the above procedure.

[Kim]

Excellent Pat, takes the trial and error out of it.

Which got me to wondering if there is a way to associate, or lock, a dimension object to 2 points then alter the dimension to the desired size. In this case place 2 loci on a given length then group them with the image object, using the loci as the locking points for the dimension. I don't think this is possible but if anyone does know a way ... ?

[modpod77]

you can do it in a new blank drawing.

"Say your drawing template is set to imperial 1/4" scale & you want to use this for your output but have a sketch with dim's called out in Metric. Continue with your normal drawing template, when you input values from the sketch just (eg 3655) just type this value into your OBJECT INFO PALLET but be sure to add mm at the end (ie 3655mm) and VW will do the math for you. Your drawing will be in imperial, but the values will have been converted. This also works if the values were noted as decimal Meters (eg 3.655) just type a M after this value (ie 3.655M)."

thanks for this, Jim

[Pat Stanford]

If the object you want to scale has "vertices", then you could create an Associative Dimension. Then when you change that dimension, the associated object should change also.

Unfortunately, most scans do not have any "vertices" to associate the dimension to.