ISO 10135-2007 ("Geometrical product specifications - Drawing indications for moulded parts")?

S1mon

I just saw that Creo has added support for ISO 10135-2007. I was unfamiliar with this standard. Does anyone use this regularly for their projects? I haven't run into this in any drawings I've seen.

It seems to be based on the concept that you could just model molded parts with no draft and annotate them with the intent of how they should be drafted. I really can't imagine that. I start modeling with draft because of how critical it often is to the design and manufacturing of parts. All of the parting line mismatch, sink etc that it covers I've always seen as notes.

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

NeilCooke

Hmm, not sure I agree with that standard. Draft has an affect on fit and function so if you use this you either don't care or are just lazy?

nick_papageorge073

Yikes. That seems a horrible idea.

Phillip_B

We here in Europe use the standard. However, the part with the draft definition is rarely or never used.

However, the standard has important other parts, such as the definition of tool offset and burr on tool parting, which we use very often.

In a feature request of mine, I have been asking for the implementation of the standard in Onshape for a long time, since it is enormously important for the complete definition of an injection molded part with all quality relevant properties.

Phillip_B

Here is an example drawing in which the standard ISO 10135 is used:
PP_Formteil-Web_V2-0-0_3840x2160.jpg (3840×2498) (toleranzen-beratung.de)
The draft part is not so interesting, but the drawing shows a large part of the requirements I have for onshape, which unfortunately are still not met. Therefore a productive use of onshape is not possible for me yet.

S1mon

@Phillip_B

I'm not as familiar with ISO GD&T modifiers (e.g. GN, GX, CC, etc.). For better or worse I've been using ASME standards for many years. I see that Solidworks added them in 2019. It makes sense that these should all be available in Onshape.

That drawing example is a pretty extreme of GD&T for such a simple part.

1. What sort of sampling/inspection plan is used for this? Is this just for first article inspection? This seems like it would take a lot of time to fully inspect and requires dedicated fixtures and a CMM.
2. How does the inspector know how to apply the 4±0.5 (LS) H←→K call out? That could involve 1 pair of points with a CMM or 5000. Also with the part constrained, how is it even possible to measure this closer to point 'H'?
3. If the drawing and 3D model accurately reflects all the draft, it seems like there's zero draft on many surfaces. With a PP part that has no texture, that's not impossible, but surprising. 
4. The [B] datum is specified with 3 cylindrical datum targets (which makes perfect sense), however there's nothing to clock the part (except maybe the ejector pin locations?) so the gage R&R of an inspection process could be quite off if the part is significantly out of round at the [B] datum surface.
5. The surface enlargement symbol on the ribs is interesting. Is that to allow the molder to add texture or undercuts to help hold the part on the core prior to ejection?
6. I would love to work with the tooler/molder who could handle this drawing correctly. I assume they are in house, in Germany. I've worked with a lot of different toolers/molders/CMs in China and some in the US. Basic GD&T is challenging for so many of them. 

Phillip_B

Hi @S1mon ,

Yes, this is an extreme example. Just an example of a consulting company

But it reflects a large scope of needs that are used in our industry (Automotive & Consumer Goods).

1. the drawing describes the measurement scope of the initial sampling of a part. In the drawing no markers are set for the series-accompanying measurement. But you are right: The measurement scope of the initial sampling (PPAP) is only possible with a CMM. Very often, CT measurements are also used for complex parts or when surface or line tolerances have to be evaluated. However, this is state of the art in automotive industry. 

2. We handle it in such a way that there is a measurement specification for each dimension. This describes exactly how and how often a dimension is to be measured. In the linked example, the wall thickness between the points H and K is checked and, since it is a rotationally symmetrical part, around the entire circumference. We often use this type of dimensioning when the wall thickness is a critical feature. For evaluation, a false color analysis is usually used with the help of a CT.

3. general deviations are usually listed as a general surface tolerance for non-tolerated areas in the title block. 

4. no definition of rotation is noted in C in this example. This may be possible, but always depends on the requirements of the part. Personally, I would also rather prefer a fully defined reference system.

5. yes

6. i quite agree with you there. We work with toolmakers in Europe and China/Asia. It is sometimes challenging to find a supplier that fully understands the requirements. But there have been developments here as well in recent years. Automotive suppliers often understand this very well, others have to be partially developed.

I know that our requirements for drawings are considerable. However, this goes hand in hand with the fact that the principle should be that a drawing describes a product as fully as possible and is a contractual document. Our drawings are the basis for several hundred thousand euro/dollars expensive tools that have many months lead time and must produce several million shots within a consistent quality (class A surfaces). Therefore, the definition must be crystal clear.