how many have to go from sketch to toleranced print?

Just wondering how many IDers have to do everything from research, sketch, etc, all the way to specification writing and materials and process research to detailed, toleranced blueprint, then setting up Q.C. documents/protocols, doing first piece inspections, etc.

Another words how many IDers actually function also as design engineers only without the BSME for these last items:
(detailed toleranced blueprint, then setting up Q.C. documents/protocols, doing first piece inspections, etc. )

I am asking because I have always done this at my staff jobs and I am wondering when I go into a new position and show I’ve done this sort of stuff will it create an expectation for me to do it even though they have resources to do it, or will it “put off” the design management because I am heavy on the technical?

I don’t think that knowing the whole process will ever hurt you. I’d always see it as a positive.

I’m in that category. Lone designer for a small manufacturer with a factory in China. I sketch for ideas and use Pro/E to model and make blueprints. Mostly furniture and lighting.

Been doing it for years.

Not so much tolerancing any more. The 3D model hand-off has made me lazy.

Small companies = required multitasking.

I too do complete concept design to production databases, but I’m not sure I totally agree with this comment on tolernacing. Depending on the process (even injection molding), I always create control-line drawings with the critical tolerances, material and finish specs, etc. Of course I always reference a 3D files, but without that document, it’s really challenging to hold manufacturers to a specific standard–particularly when there are critical fit issues. Just submitting a 3D files and saying, “Hold everything to +/-.005” doesn’t really cut it.

For other plastic processes like thermoforming, rotomolding, etc., I would never give a molder just a 3D file without a control document. With sheetmetal, machinings and castings, it’s depending on how the shop is producing the part. In the case of sheet metal, I might give them layflats and an toleranced drawing for the bent and assembled part. Sometimes I do a fully dimensioned drawing if they’re machining by hand. And as you know, the dimensioning should take into account this machining process.

Each process and material has it’s own specific characteristics and challenges and a good amount of that is resolved (and controlled) through this document. Also, your drawing with critical tolerances affects the cost of the part. If I hand a 3D database to a manufacturer and tell them to hold everything vs a few key dimensions, the second part will more likely be less expensive.

For me it’s hard to separate this part of the process with the rest of design. I know there are some ID’s who aren’t comfortable in this space and would rather have an engineer handle it. But from my perspective, the more you can understand and participate in the total design process, the more effective a designer you’ll be.

But to address IDguy88’s original question: Yes, it can be challenging for some design firms to figure out how to use you if they’re structured to keep those disciplines separate (“Okay, designers over there, and engineers go over there…”). BUT, like NURB said, I wouldn’t see this as a disadvantage. In small companies your ability to “do it all” is really valuable. In larger companies, it gives you the experience and credibility to manage those efforts–even if you’re not doing them yourself.



W, do find it necessary to use GD&T or an ANSI Y14 standard when doing detailed dimensioned prints? I was wondering if it is valuable to learn this to better control the drawings. Great work on your site by the way.

Thanks for the kudos on my website :slight_smile: . It’s really difficult to communicate all the detailed work that goes into the projects I do. So many visitors like to just flip through the glamor shots, so I added the case studies to dive a little deeper… I need to do some more of those…

I typically use ANSI standards (or ISO is the drawing is metric) and GD&T when there are critical fit issues (like flatness or squareness). I did go through the trouble of learning geometric tolerancing (it’s not that difficult) because it can be challenging to accurately describe what you’re looking for without it (like how one part is intended to fit into a feature on another part. Using matching tolerancing schemes helps reinforce this intended relationship to the manufacturer. If you can get them to understand what you’re looking for (and why), you have a better chance of getting your desired results… Or you can have an engineer try to communicate that for you; I just prefer to do it myself since I’ve been doing it that way for so long.

However, I try not to get too carried away because, like I said before, the more dimensions you apply, the more that have to be checked by QC and the more expensive the part could become (look at the dimensions as if there were little dollar signs peppered all over your drawing, because that’s how a lot of molder will see it). I’m pretty stingy with my dimensions and try to allow the 3D geometry speak for itself. But at the very least I do overall dims, critical fits, material, color and finish.

Hope this helps.


I just wanted to say: “Great Post !” Thank you.
Should be helpful for beginners and pros alike. Dimensions as Dollar signs. That’s gold, man.


Thanks, mo-i. Cheers,


One thing we used to do at a company where I worked was to use “reference” dimensions, they were put in parenthesis, these indicated that the dimensions were for reference only and not to be used by Q.C. this way we could have more dimensions to describe the part without impacting inspection.

Yup, I do that as well. Reference dims are also good to confirm or reinforce a particular dimension in a detail view that may be shown somewhere else or stated in the notes (like a nominal wall). It’s typically bad practice multi-dimension a feature in a drawing, but reference dims allow you to get around that.