Need help on parting line tool

[thburn]

Hi,

I wonder if someone could help me with the parting line tool?

- What is it for?

- Is there a small tutorial / video available to show how it works?

Thanks!

[AndrewSears]

The parting line is a helpful tool for making molds for plastic parts.  It helps to make sure you can get the part of of a mold cavity by defining the outer edges so they do not become trapped in the mold.   

Here is another post from yesterday with some comments about this feature.  http://forums.autodesk.com/t5/Get-Help-with-Fusion-360/Issues-with-the-parting-line-tool/m-p/4906816...

We are working on the training material to help you use the tool better.

Thanks,

Andy 

[Oceanconcepts]

To use the tool you need to 1) select a body and 2) define a direction to pull- by selecting an axis in the origin, for instance.   The problem with the tool as as I see it is that it wants to split the body along the parting line as part of the action- not just find the parting line.  On a complex body this nearly always fails.  

I have only been able to succeed with this tool by selecting the split face option, then using the face edges it creates to generate surfaces to do the splitting, or to create sketch lines if I have other things in mind. I can then create a ridge, or thicken the surface on one side of the parting line. For molded parts, you usually want to make some kind of definition there, as parting lines are never totally smooth transitions when manufactured.  Better to make it look intentional.  The split face option seems to work well for finding the parting line, the splitting of the body option not so much.

[thburn]

Hi Andrew and Oceanconcepts,

thanks for reply.

@Andrew: The link you provided is not working 

[Oceanconcepts]

I think Andrew was referencing my grumbling here:  http://forums.autodesk.com/t5/Get-Help-with-Fusion-360/Issues-with-the-parting-line-tool/td-p/490681...

Which is just a few posts distant in this list. 

[deyop]

Sorry for the delay in providing the video on using the Parting Line Split command.  The purpose of the tool is to automatically define the outer boundary of a body relative to a vector.  Generally the reason to do this is to figure out how to split a body for molding a part.  Hope this will help explain how to use the command.  Let us know if this command satisfies your needs or if there would be other ways the command could be used.  Ron made some good points in his post we will have to consider for improvements.

[jeff_strater]

Thanks for taking the time to provide this input.  A quick comment regarding the "always fails" point:  The Parting Line tool has 3 modes of operation:

  1. split a solid body

  2. split a shelled body

  3. split faces only

Of these, 2 and 3 are much more stable operations on complex, curvy designs (like those produced by TSplines).  The reason why splitting a shelled body is easier is because the surface needed to do the split can be very narrow.  However, splitting an entire solid body, especially if the parting line is a complex 3D curve, requires a much more complex surface to be generated.  We are certainly trying to improve the reliability of the solid split, but in the meantime, if you are working with a shelled body (I realize that this is not always an option), make sure the shell has been applied before the split, and use the shelled body option.  For instance, in this example (just a made-up case, nothing realistic), Solid Body will fail, but Shelled Body will succeed:

here is the parting line shown on the body:

Second, If you want to just generate the parting curve, use the Split Faces Only mode - this will produce edges on the model that represent the parting line.  You can then use the Include 3D Geometry command, and select the parting edges, and this will create 3D curves that match those edges.

Hope this helps a little,

Thanks,

Jeff Strater (Fusion development)

[kingson138]

Hi Paul your videos are always amazingly good!

[kingson138]

Hi Folks,

In order to design a product for Mold (Mould) making the designer has to studying a little bit more on the process by discussing with a mold maker first. Mold design is a special field because it involves lots of engineering including the uses of materials, sizes of the molds (for any particular mold size machines), devices required, etc. Mold design guidelines are completely different from those for 3D printing. 3D printing can almost does anything as long as its  guidelines can be matched. A product itself should be designed for Mold Making to start with. And most important of them all, if it is really required, try not to combine the body parts into one single body. Arrange them in a proper array of Components in a main Assembly. And remember, if side ways opening of the mold is required the designer has to observe more guidelines on that.  The usual hollow body requirement of 3D printing will not work. An efficient use of materials should be designed for that particula mold type operations in mind. There are a many different kinds of molds for different types of plastic manufacturing. For example, there is a difference between Rotational and Injection method. As well as the so called "Extrusion Molding" method for making plastic bottles for detergents, etc.

Using the Parting Line Split tool is very good especially for hollow bodies. Bear in mind that if it is going to be a very good and fast moving consumer product the look and feel of the product are important. Try not to split a Doll in half otherwise it will look terrifying, right?

Study the designs of different products in the market and make some adjustment in your design concept.  Remember, to make things commercially try using the simplest forms. It might sell faster and easier to make.  How much it will cost the makers and consumers are the ultimate intention, isn't it?

An example, here I did not use the "Line Split Tool." Only the Body Split Tool to seperate the base from the body and then extrude the proper parts to match up with the whole profile. The components were designed to be pulled apart for mold layout designs. (This is part of a real commercial product.) A complete STP file will be sent to Mold Designers for final layout. This particular design will avoid making molds that have to open side ways and will save a lot of mold making costs. Just by using seperate components at the base:

     

I have a little demonstration of what a set of molds look like at the gallery called "Industries"  by Kingson Lee. If you have time do take a look.

[kingson138]

In regards to the above example:

The Line Split Tool I was referring to is actually the "Parting Line Tool". This example can be parted with that tool in between for easy one pass operations (one assembling after molding) but it looks bad. The way I did it requires more assembling after Molding but the whole product looks nicer and thus easier to sell. The easy one also requires assembling but only one step less but might make the product less desirable.

One more step is to be taken, to make more efficient use of plastic materials, the base block should be hollowed out a little bit. Attached is another screen shot. Please understand this is part of a bigger project, so only these related parts are shown (This is my own project, not my clinet's so it will be fine to show this.)

[Oceanconcepts]

Here is an example of the kind of thing the Parting Line tool has trouble with, even as a shell. It's the base of an instrument housing, shown with draft analysis. I suspect the loop at the front can't be solved by the splitting algorithm. And in any case, I don't actually want to split the entire form at the parting line, just a portion of it. There are many reasons for wanting to locate the parting line other than needing to split the body. 

However using the Split Faces option as Jeff suggests, and either creating 3D curves or projecting the curves to a sketch plane, allows me to control exactly where the split happens, and works perfectly.

[kingson138]

Hi Ron, this Parting Line Tool is actually not bad for simple bodies. I am an old fashion guy. I always believe in designing files that conformed to the specs of methods of manufacturing. But it is good to include that tool. I used it to divide a simple body into halves. But we know that no matter how hard or how perfect we designed the files for certain types of molds (moulds) the Mold designers always make changes since they are really the ones who knows how to make the products in the molds. Maybe you can design the molds yourself as well. I always let my designers make suggestions and then I let them change the designs somewhat. I think that is the best way.  Just as I always said "Do not combine the bodies unless it is needed". These mold designers have special feelings towards "parting components". They always make  suggestions that I do not like but I always make changes until they said "good! "

[Oceanconcepts]

Kingson,

Yes, it is very important to get the mold designer involved in the process- after time you can get a feel for what they need. Mold design is very much a specialty, one I will leave to experts. We are fortunate to work with a very good designer. For us, since our housings must stand up to quite a lot of pressure, tolerances need to be tight, so you need to know how much a particular material will shrink in what direction. Reenforced plastics also require specific types of designs to work well. And we have to at the same time be designing how things will be assembled in production so as to allow testing of the electronics, and potentially repairs.  That's why I might not want to split the entire body, but just create an access panel.  All these considerations make Fusion's flexibility very valuable. 

The basic function of the parting line tool, splitting faces, works great.  What would improve it for me would be an option to directly create a parting line as a 3D sketch. But that's a very minor quibble. I might suggest making split faces rather than split body the default option- it's going to work more often on more designs. As with most things, it's a matter of learning to use the tool.

[kingson138]

Hi Ron,

Yes, mold making is a very specialized field and the devices inside are master pieces themselves.  Well Fusion 360 Parametric Mode already improved quite a bit and I am using it now. It does provide me with the right kinds of tools to design products for my few Pharmaceutical Clients. They have very straight requirements on weight per bottle or per product, total bacterial plate count, chemical composition, all these required a Chemist to understand. That is why I do that for them because I myself is a certified chemist. I also use Fusion to design lifestyle products for our own shops. My partnership is a Plastic Company that builds all these for myself and my clients. I do leave the mold designs to my mold designers but I got most of the things perfectly fitted and they do not have any complaint anymore.  The only three things I hope to have in Parametrics are the capability to scale components/bodies; Paste New for Components (now have to combine all bodies in a component to one single body); and most of all, the ability to MOVE offset planes to any direction like in DM mode. It can only do that in Create Form and Create Basic Feature mode now. I have to complement them on their "Property" selection on the Browser. It is very useful for me to estimate the weight per product per material selected.

Well have a good week. I do use Fusion360 every day. And usually I worked until 3am with it so I believe we know what it is by now!

[jeff_strater]

I like the idea of automatically generating the 3D curve for the parting line. That does seem useful. Yes, it's a small enhancement, but if this is something useful, it seems worth doing.

Jeff Strater (Fusion development)

[kingson138]

Hi Jeff, yes it is a very good and useful idea!