Something I really like to do. In many cases I replace castings with tubular or billet alu parts. Many times I can greatly reduce the parts size while increasing the strength. My latest bit of fun is the redesign of the rear upper control arms for my 04 X-Type so I can make the bushings serviceable and if I get creative I will make camber adjustable as it is not easily done with the OE setup.
So does anyone else here feel the need to redesign perfectly good OE parts just because they can? Does anyone design there own custom parts?
I just think it is cool and a fun to build things virtually before I actually build them.
This is just the beginning of the A arm the design work. It needs a lot more refinement. It is showing me what space I have to work with and I will start design through subtraction.
This is super cool. I'm looking forward to reading more about your process.
I've built a few custom parts, just started using CAD (where C is not Cardboard) to design them. Some I plan to make are a 3D-printed ITB adapter, CNC'ed drop spindles (for higher roll centers), and tubular front LCAs for unsprung weight reduction and caster adjustability.
Edit: Some pics of my first CAD designed part, a CoP deck for a 4AGE 16v:
What I usually do is kind of "hokey" but it works for me. If the part is small enough I scan it as you can see in the background in the image above. I use this in a top view in conjunction with good old vernier calipers and generate a 2d top view. Then I "pull" it up out of the 2d drawing. The one above I will be removing allot of the metal in the center and making it into an I beam with webbing that is perforated as most of the loading is in compression. I was thinking of going tubular but there is a width issue with the rear half shaft so I have to keep it narrow about .80 inches is the max width on the OE part but it uses a "T" center section if I make it an "I" I think I can get it down to about .4 or .5. Another possibility is try the tube and raise it up to the top cord of the center section but I will have to see. This would make adding a camber adjustment rather simple actually as all I would have to do is weld in a threaded bung on to tube and put a spherical mount threaded in to it with locking nuts.
Like I said it is fun and in AutoCAD it is easy to mod things and look at them virtually. What would be cool is to have a 3d printer that I could print the part and use it for fitment before a final hard part is made/machined.
Here are some foglight mounts for my Samurai. All I did was make a prototype in old-school CAD 
and drop it off by a guy who does fab work.
Hay the other "CAD" is equally as good some times. Done it many times!!!
So does anyone else here feel the need to redesign perfectly good OE parts just because they can? Does anyone design there own custom parts?
I do all the time. I've redesigned nearly everything in regards to chassis and suspension parts for my Europa build:
And recently I've been toying with a bike carb manifold for the Zetec that will be powering the Europa. If I had a 3D printer there would be a plastic manifold hanging off the engine to make sure it all works. The current plan is to create an aluminum one with the lost foam casting method.
In the past I've also re-drawn existing blueprints (Lotus 7 and 11) and created 3D autocad models of them.
Rod
RoddyMac17 wrote:
And recently I've been toying with a bike carb manifold for the Zetec that will be powering the Europa. If I had a 3D printer there would be a plastic manifold hanging off the engine to make sure it all works. The current plan is to create an aluminum one with the lost foam casting method.
In the past I've also re-drawn existing blueprints (Lotus 7 and 11) and created 3D autocad models of them.
Rod
This is similar to the ITB adapter I'm working on. You can 3D print this in Ultem and it'll work just fine (although you might want to beef it up for strength). You could even 3D print it in ABS and it would work, but there wouldn't be much margin for error between reasonable engine temps and the point where ABS gets gooey. FSAE teams routinely run ABS intake manifolds though.
As a bonus you get less engine heat in your intake.
dean1484 wrote:
Something I really like to do. In many cases I replace castings with tubular or billet alu parts. Many times I can greatly reduce the parts size while increasing the strength. My latest bit of fun is the redesign of the rear upper control arms for my 04 X-Type so I can make the bushings serviceable and if I get creative I will make camber adjustable as it is not easily done with the OE setup.
So does anyone else here feel the need to redesign perfectly good OE parts just because they can? Does anyone design there own custom parts?
I just think it is cool and a fun to build things virtually before I actually build them.
This is just the beginning of the A arm the design work. It needs a lot more refinement. It is showing me what space I have to work with and I will start design through subtraction.
Interestingly, control arms are one of those situations where cast can be much stronger than tubular. They tend to have oddball shapes and weird load paths, so a cast piece can put the material where it needs to be. Billet would just be a low volume, high cost way of accomplishing the same thing.
Just look at the front lower control arm for the Miata. V8Roadsters keeps trying to make a tubular version and they keep adding more and more reinforcements to them to keep them from cracking.
Now, if you're trying to add attributes that the factory parts don't offer such as extra camber adjustment, sure.
We prototype parts all the time, of course 
The initial CAD models used to be made from measuring, but we have a new 3D scanner that will hopefully make that work better. Or it may make the process more difficult. We also have a 3D printer for building prototype parts to check fitment, but since it's a hobby-grade unit they're only good for rough testing. High precision, low accuracy.
I do a lot of DIG (draw in garage) designs and CDF (Cut Drill File) for small parts I make prototypes and one of projects. just finished brake duct backing plates and current project is a 2 piece hinged splitter that allows different length front sections while also being height and pitch adjustable. I'm working on plastic body panels to blend the splitter into the cars original bodywork now. Do I need to make it so complicated? No, but I did anyway.
Are any of you guys who like to play in CAD programs that can be used on a CNC machine interested in doing a design for swan neck style rear wing supports for my car? I received an offer from someone with CNC capability of large pieces. There's no money in it but possible internet fame.
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I am looking at adding the ability to adjust camber and make the bushings serviceable. As things are now if the rear camber gets out of spec the only way to fix it is to loosen the whole rear sub frame and shift it. This is a serious PITA. It also has the precision of a hand-grenade in terms of fine adjustments. This is a common problem with these cars as well as the other ford variants of this platform (Volvo and ford cars).
As for low volume and high cost. That sounds perfect for any Jaguar component. 
I wish that I had the chops to re-engineer heads. Take a motor like the Corvair, which has a perfectly fine bottom end, but breathing issues in the heads. It would be so fine to correct those issues without the use of a welder and a milling machine.
edit: of course a new cast head would require lots of machining as well, but at least with all the processes automatable, you'd have great repeatability.
In reply to RoddyMac17:
That is impressive work there.
