Head design and casting cost?

[Sweet P]

If anyone is Interested I can make up some images to explain the difference.

Yes please do I'm interested

[xr4x4ti]

If anyone is Interested I can make up some images to explain the difference.

When it comes to water cores, there is no "good-enough" CAD system.

Yes please

[volodkovich]

There is no doubting the high end systems are much more suited to the job. The question is whether low end systems are capable of modeling usable and suit for purpose performance cylinder head castings. 3d printed sand moulds and lost-foam/PLA investment casting removes a lot of the need for the flexibility of the model, no need for parting lines, drafting for core boxes etc. I've been happy with SW for my intake manifold castings so far, though they are all fairly simple IR designs etc I believe they have much nicer port shapes than any OEM manifold they replace.

Not everyone has $50,000 to spend on a CAD system and believe it or not many 'good' Cylinder heads were hand drawn and hand carved by pattern makers in the past. So to me its a matter of you get what you pay for. I can iterate port shapes and probably cast 10 test heads for the price of a years subscription to a pro CAD system, if it were possible to buy them in my country.

Keen to hear if you have any tips to help with modeling John, i'm interested in how the pro systems work as well. I use lofts and adjust end conditions and have no real issues controlling port/runner shapes.

[JoePorting]

I had my billet SBC head made with SW and thought it cam out great. I had my current SBC head, manifold, and valve cover made from SW and I think they came out just as good. I was under the impression that Edelbrock/AFR/Brodix all used SW too, but I guess they might use something else.

I see a cylinder head and all the related components as being pretty low tech when compared to the aerospace industry. I can't see where some other CAD software can be much better, but then again, I'm not much of a computer guy.

[SchmidtMotorWorks]

This is the base surface of a port (before guide boss and other details are added.
The base surface is one single face created without guide or section curves in NX.
(I modified this surface to show here, I never show clients work or identities)

port_1.jpg

Here you can see the UV grid curves on the surface, these enable you see the parameterization of the surface. Ideally the UV curves will flow smoothly and with shape that follows the flow direction and curvature change.

port_2.jpg

The curves in this images below show the reflection of the lines that would occur if the port were in a spherical room with stripes on the walls. The shape of the curves tell you about the curvature of the surfaces and help the designer to see inflections (unwanted reversals in curvature). These are the same tools used to design automotive body surfaces.
Generally, when I create a surface based on a port scan, I make it close to the scan until the lumps in the shape become evident, then I use the CAD tools to make a high quality smooth shape that isn't possible inside a port with revolving tool.

port_3.jpg

port_4.jpg

This is a reflection of a beach sunset, you can reflect any image that you choose.

port_5.jpg

These are some of the controls for the surface shape.
These controls enable 1,000's of times more control over the shape than section and guide curve controlled surfaces.

port_6.jpg

Here is a video showing the reflections in rotation.
There are many other tools involved in evaluating and adjusting shape.

https://www.youtube.com/watch?v=ZdMz5rV ... e=youtu.be

In the big picture, to do effective work, it is ideal if you can use one software that can do all of the following tasks, using the same files without translation so that any change made to the design files is associatively updated to the downstream processes.
If you do them with care, you can reuse a finished project as a foundation to the next project and add refinement in each cycle. Frankly, if you don't do associative reuse, you won't be competitive or have time to do excellent work.

Design
CFD Analysis
CNC Machining
Tooling Design
Tooling Machining
Fixture Design
Part Machining
Packaging Design

[mekilljoydammit]

I see, you're doing it with surface modeling! I just spent a couple minutes in Solidworks and think I found the functionality you're talking about, but it's not a part of things I've dealt with much before, so that'll be a learning curve. It's definitely not part of the normal machine design kind of things I typically do.

I'll try some basic stuff after work.

[BradH]

It would be interesting to hear from Barry Rabotnik (sp?) on what it took to bring his Survival Motorsports FElony cylinder head from concept to market.

[Ken_Parkman]

To add a comment - the guy doing the modeling also has to be very good - it's not for somoene who is just dabbling. Making the model of the head at the various stages of manufacture is relatively straightforward; a complex aerodynamic shape that you can precisely control is another level of skill altogether.

[strokersix]

Thank you for sharing, Schmidtmotorworks.

[SchmidtMotorWorks]

I see, you're doing it with surface modeling! I just spent a couple minutes in Solidworks and think I found the functionality you're talking about, but it's not a part of things I've dealt with much before, so that'll be a learning curve. It's definitely not part of the normal machine design kind of things I typically do.

I'll try some basic stuff after work.

Surface modeling does not describe the difference between what I am doing here and how SolidWorks or most CAD systems.
Surface modeling generally means defining a shape by sweeping a section curve along guide curves, or lofting through a series of section curves.
This requires a lot of individual surfaces to make a reasonable shape.
You won't create a surface of this quality and detailed control with swept or lofted surfaces.

What I do is different, I create a single surface with hundreds of control points. The points are not on the surface, they are more like magnets pulling on the surface (called poles). There are additional controls for how the emphasis of the poles diminish over spans of poles.

[arlancam509]

Surface modeling does not describe the difference between what I am doing here and how SolidWorks or most CAD systems.
Surface modeling generally means defining a shape by sweeping a section curve along guide curves, or lofting through a series of section curves.
This requires a lot of individual surfaces to make a reasonable shape.
You won't create a surface of this quality and detailed control with swept or lofted surfaces.

What I do is different, I create a single surface with hundreds of control points. The points are not on the surface, they are more like magnets pulling on the surface (called poles). There are additional controls for how the emphasis of the poles diminish over spans of poles.

dare i say, excessive and unnecessary complication?

i have long gotten out of the game of defending "my" tools, so this feels very odd to me. haha. i have 28 years of cad experience. 18 of those are in the 3d realm. you can say i have seen my fair share of paths and routes to get to a destination. i have also seen some guys that could really produce some crap with the highest level of cad system and i have seen guys that could make autocad look like gold. this cad package discussion is just like the ford vs chevy vs mopar debate. they all have their strengths and weaknesses! but at the end of the day, if you know what you are doing, you can get to where you need to be. in short, i don't think solidworks is as far behind as we might think and in the right hands, almost as capable as anything else.

[mekilljoydammit]

I see, you're doing it with surface modeling! I just spent a couple minutes in Solidworks and think I found the functionality you're talking about, but it's not a part of things I've dealt with much before, so that'll be a learning curve. It's definitely not part of the normal machine design kind of things I typically do.

I'll try some basic stuff after work.

Surface modeling does not describe the difference between what I am doing here and how SolidWorks or most CAD systems.
Surface modeling generally means defining a shape by sweeping a section curve along guide curves, or lofting through a series of section curves.
This requires a lot of individual surfaces to make a reasonable shape.
You won't create a surface of this quality and detailed control with swept or lofted surfaces.

What I do is different, I create a single surface with hundreds of control points. The points are not on the surface, they are more like magnets pulling on the surface (called poles). There are additional controls for how the emphasis of the poles diminish over spans of poles.

No, I understand what you're talking about now - Solidworks does have freeform surface modeling like you describe. I can't speak to how capable it is much less how capable compared to CATIA/NX but it's there.

[SchmidtMotorWorks]

I see, you're doing it with surface modeling! I just spent a couple minutes in Solidworks and think I found the functionality you're talking about, but it's not a part of things I've dealt with much before, so that'll be a learning curve. It's definitely not part of the normal machine design kind of things I typically do.

I'll try some basic stuff after work.

Surface modeling does not describe the difference between what I am doing here and how SolidWorks or most CAD systems.
Surface modeling generally means defining a shape by sweeping a section curve along guide curves, or lofting through a series of section curves.
This requires a lot of individual surfaces to make a reasonable shape.
You won't create a surface of this quality and detailed control with swept or lofted surfaces.

What I do is different, I create a single surface with hundreds of control points. The points are not on the surface, they are more like magnets pulling on the surface (called poles). There are additional controls for how the emphasis of the poles diminish over spans of poles.

No, I understand what you're talking about now - Solidworks does have freeform surface modeling like you describe. I can't speak to how capable it is much less how capable compared to CATIA/NX but it's there.

I have SolidWorks, 3DS (Dassault Systems) supplies it to me for application development.

"Surface Modeling" and "Controlling a Surface by its Poles" are 2 different things.

[SchmidtMotorWorks]

Surface modeling does not describe the difference between what I am doing here and how SolidWorks or most CAD systems.
Surface modeling generally means defining a shape by sweeping a section curve along guide curves, or lofting through a series of section curves.
This requires a lot of individual surfaces to make a reasonable shape.
You won't create a surface of this quality and detailed control with swept or lofted surfaces.

What I do is different, I create a single surface with hundreds of control points. The points are not on the surface, they are more like magnets pulling on the surface (called poles). There are additional controls for how the emphasis of the poles diminish over spans of poles.

dare i say, excessive and unnecessary complication?

i have long gotten out of the game of defending "my" tools, so this feels very odd to me. haha. i have 28 years of cad experience. 18 of those are in the 3d realm. you can say i have seen my fair share of paths and routes to get to a destination. i have also seen some guys that could really produce some crap with the highest level of cad system and i have seen guys that could make autocad look like gold. this cad package discussion is just like the ford vs chevy vs mopar debate. they all have their strengths and weaknesses! but at the end of the day, if you know what you are doing, you can get to where you need to be. in short, i don't think solidworks is as far behind as we might think and in the right hands, almost as capable as anything else.

It is less complicated, more flexible and returns superior results.

[SchmidtMotorWorks]

Any of you guys that claim a general purpose CAD system can accomplish the same results are invited to post an example.