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Advanced Drawing Question: Adding an Automatically Increasing Dimension Prefix?


New member
Hello All,

At my place of employment, we consistently use the "inspection" dimension display time type, and add a prefix of "Q#:" before the dimension, where the "#" represents a numerical value from 1 - n that signifies the dimension number during inspection. Below is a screenshot of how I have been achieving this in past:

Q-Number Dimension Prefix Screenshot.jpg

It is best to have Q-Numbers with similar numerical values pointing to the same feature, as it makes it much easier when examining an inspection report provided by our quality department for incoming parts. The problem comes in when it is necessary to add a new Q-Number Inspection Dimension to a drawing that has a large number of Q-Number Inspection Dimensions, all of which have already been previously assigned to the dimensions. In order to keep the Q-Numbers similar, it requires ALL of the Q-Number dimensions to be edited one-by-one.

Example: A drawing has 100 Q-Number Dimensions Q1 through Q100 on a drawing. If Q-Number Dimension Q10 previously established is for a hole diameter, and it has been decided that we need to add a Q-Number Dimension to the Hole Depth as well, I would like for this hole depth Q-Number Dimension to be Q11 or Q9 rather than Q101, as this will keep both dimension values next to one another on the quality report. To achieve this, I would have to edit Q-Number Dimensions Q11 through Q100 one at a time, increasing each numerical value by 1 to keep all the Q-Number dimensions sequential. Needless to say, this can be a TON of work, and extremely time consuming.

To my question. Can anyone think of a way of establishing a parameter that automatically tracks this inputted Q-Number Value? I would like to be able to place the Q-Number Prefixes so that the Q-number prefix for Dimensions is as follows:
The Q-Number prefix for Dimension 1 is Q#1 where #=1→Q1
The Q-Number prefix for Dimension 2 is Q# where the #=(# from Q1)+1→Q2
The Q-Number prefix for Dimension 3 is Q# where the #=(# from Q2)+1→Q3, etc.​
This way, when I add an additional Q-Number Dimension, all of those after it will automatically increase by 1.

Any suggestions on how to accomplish this, if it is even possible would be greatly appreciated!


New member
That sounds like a lot of work if it is even possible. I always look for an easier alternative that would solve the problem when confronted with something like this. Suggestion:
For each feature with a quality dimension connected to it assign a letter, maybe two letters depending on how many features you might want to assign Q dimensions to. After the series of letters there are numbers that start with 1. Now you have quality dimension AA1, AA2 etc and for the next feature you have AB1, AB2. If you anticipate having more than 676 features to assign Q numbers to you will have to have three letters - a QC guys nightmare.

Depending on the company you work for it might be easier to pursue your original plan but if the original plan can't work think of the time savings, not to mention the agravation. Tell them to quit being victime of functional fixedness - we've always done it that way is not an acceptable response.


I would never put those "Q numbers" on the engineering drawings. In fact, even I would not even use the "inspection" oval as it's not part of any national or international drawing standard. However, if your company wants to use the ovals then I'm sure you can't change it. However, there are a couple of different tools available that will add layout bubbles automatically and some will even create spreadsheets automatically populated with the dimensions and tolerances. This is something the QA department should be doing, not product engineering.

Check out programs like Inspection Expert, there are many others.