Feature Highlight: Scale & Calibration

Marco M

This week, we're talking Scale and Calibration. Getting accurate measurements starts with setting the right scale and Bluebeam makes it easy with Calibration. With just a couple of clicks, you can ensure your documents are properly scaled so that every measurement you take is precise. Whether you're measuring distances, areas, or volumes, calibration keeps everything accurate and reliable.

1. What role does the Scale and Calibration tool play in your project workflows?
2. How do you ensure accuracy in your measurements and drawings?

Let's share some best practices!

https://www.youtube.com/watch?v=kBblAaoRYfk

STR - Kristin

For the work I do in creating new tools, scale is critical. I use viewports with different scales to verify they are working properly. As for calibration on drawings with no scale noted, I typically use a known measurement, like a door or gridlines, then test it someplace else on the drawing to confirm it's correct.

bcostlow

This is one of my most used tools. I struggle with trusting the measurements though, and could greatly benefit from a deep dive on the topic.

When calibrating, is it best to use the largest known dimension as the benchmark?

My thinking is that the longer my line is, the more of the drawing is taken into account when scaling to the subsequent measurements made. For instance, let's assume we have two known lines to choose from, one at 3" representing a 30' wall and one at 7" representing a 70' 2" corridor. The 3" line representing 30' would result in a scale of (1:10). If I use that scale to measure a line that is 7" long, the result is exactly 70'. Now, if I reverse the order and use a 7" line with a known length of 70' 2" the resulting scale is (1:10.06). Using that scale, a 3" line would be 30' 0-3/4".

Obviously this is an exaggeration of what would likely ever be found, but bluebeam actually calculates measurements with a given point at which the measurement would need to be rounded. If you force it to round at smaller intervals you are making it input calculation errors at a greater rate.

Now, if we have two or more known measurement we can compare results to get the most accurate measurements possible, but when there's only one known measurement I'd recommend taking ALL measurements with a great big grain of salt. Honestly, I would just recommend not trusting any measurement where you are left calibrating the drawing. You can, but there is a level of liability taken when doing so.

All that said, I happily use the measurement tools to perform my BIM tasks. It gets me in the ballpark so I can conduct useful coordination with the other MEP trades and is invaluable to my current workflow.

JJones

A simple one for me was realising you can add your own custom preset to the calibration dropdown menu!

1:250 is a pretty commonly used one with the drawings i receive.