Cheap Fab. - Low Production

[RWebb]

I know a lot of you guys do this general sort of thing... either adding material to build up something - casting, forging, 3D-printing, FG layup, etc.

or subtracting material - by sawing, laser cutting, water jets, milling or lathe operations, etc.

How about a general guide to what techniques work best for making low production runs of something, as an example say 100 or 1,000 units of something for an old sports car...

[fanaudical]

It really depends on what the widget is, required function, materials, etc. More info would be helpful.

[petrolhead611]

You would need a full course in Production Engineering . Techniques vary according to type of component ,and material, and there often is a big technique difference between 100 off and 1000 off

[Heel n Toe]

He's trolling.



1/10 Try harder next time, weeby.

[RWebb]

Originally Posted by fanaudical

It really depends on what the widget is, required function, materials, etc. More info would be helpful.

I don't have anything specific in mind.

It seems that newer techniques allow production at lower volumes and I know there are a lot of people on here with expertise in these various areas, so I thought it might be fun to get some edumaction on it.

[Bill Douglas]

An idea I had.

Doing small production runs of replacement tail light lenses and indicator/blinker plastic for classic cars. things like blinker lenses for Karmann Ghias, E-Type Jag's, etc. Made with correct DOT and EU compliant plastic.

They don't have to be totally perfect, just looking correct to the eye.

(just send me 10% of the profits and we'll call it done )

[Captain Ahab Jr]

I design all sorts of motorsport components/assemblies usually made in many different materials and using many different manufacturing techniques

Been doing it now for 30 yrs and know I still have more to know than I already know

Hard question to answer when there are so many options to choose from

[RWebb]

ok, some specific (car) items I'd like...

FG or 3D printed 911 tail-light housings - might as well have LEDs... plug & play with the originals

a strength part would be a replacement for the heavy engine carrier (around the fan belt)

[onewhippedpuppy]

Old sports cars? For starters you’d be counting quantities on your fingers. That’s enough for most companies to bow out.

[fanaudical]

I've used these guys a couple times or one-off stuff printed in stainless steel:

https://www.xometry.com/

They seem to have access to a wide variety of manufacturing methods.

[scottmandue]

Originally Posted by Bill Douglas

An idea I had.

Doing small production runs of replacement tail light lenses and indicator/blinker plastic for classic cars. things like blinker lenses for Karmann Ghias, E-Type Jag's, etc. Made with correct DOT and EU compliant plastic.

They don't have to be totally perfect, just looking correct to the eye.

(just send me 10% of the profits and we'll call it done )

Stop reading my mind!

I was thinking of setting up a 3D printer to do just that... thou I was thinking of cars more obscure that Ghia's and Jag's.


However as others have said there is a lot more to it then just setting up shop, buy the hardware/software and learn how to use it (easy part) find somewhere to set up shop (little more difficult) find a market, in my scenario find some obscure low production vehicles where plastic parts are extremely hard to find and then find one of those parts intact so you can 3D scan it ( also my be difficult), and you bring up an interesting point of how much would DOT be interested in my little project

[rusnak]

I bought a set of RSR struts from a guy who ran a small rapid prototyping forge in San Gabriel, CA. They had the earliest 3-D printer (late 1990s) and made sand models with it. The sand was used to make castings for single cylinder engines for car manufacturers, and things like propellers for the DOD. He told me that their niche was speed and lower cost than C&C.

[Bill Douglas]

Originally Posted by scottmandue

Stop reading my mind!

and you bring up an interesting point of how much would DOT be interested in my little project

Haha, that's for the idea, I appreciate it.

I was thinking... Could buy a pile of DOT legal car trailer lights. they're cheap enough, and melt/reform that plastic. Then in the unlikely event there is a problem you can point out that they are already DOT.

[Zeke]

I ran a short production of 911R deck lid hinges that were very close to the originals and high quality. That was the easy part. Never again.

WANTED: 911 R-style decklid hinges

[RWebb]

What about pressure casting?

Newer Porsche wheels are pressure cast, tho the larger size (and higher speeds) must mean higher rotational forces. How much of the forging "space" has pressure casting taken over?

[Won]

One thing I've learned in motorsport is, anything is possible if you are willing to pay for it... Probably not much profit margin if your goal is to make a few bucks though. Just a few examples based on my past experience:


17/18" 3 piece forged wheels based on the Fuchs design (photo (C) Singer): Fully surface machined centres (front+back) with spin-formed, heat treated and machined barrels. Considering the material + machining time vs. retail price, I think it's actually a good deal.

Even the standard looking bits aren't, well, standard. This sort of the thing might be more relevant to doing a reproduction for older cars, for example.


Windscreen: Custom made to the same dimension as original but different specification. Thinner glass. Lighter laminate. Embedded heating elements a la Ford cars, so basically you can have that feature on any car you want as long as you pay!

Headlights: Custom moulded polycarbonate lens (rule says at least 80% of the original surface area must be retained; PC is thinner and lighter than OEM lens), CFRP bucket/housing, reflector sourced from OEM assembly but can also be reflective painted/chrome plated over CFRP moulded parts.


Taillights: 3D printed (carbon-filled "Windform XT" or similar) housing (saves about 20g vs. OEM for a price of 4-figure €€€ per piece), OEM lenses nicked from the production line. The internal design you see which would normally be a part of the reflector housing is just metallic silver vinyl stuck on the inside of the lens. The lighting is done with surface-mounted LED strips; light, bright, low power consumption - not DOT legal but this car technically passes TÜV in Germany (as rally cars need to drive on the road between special stages) so that's something.

No specifics but anything on an F1 car costs a lot of money and unicorn farts. But then again it's a surreal environment where bits of T800 prepreg carbon blows around in the wind and 9323 flows like the river.

If I were to do a taillight for a 911, for example, I would consider CFRP housing with moulded lens and SMD LEDs. Composite material is actually well suited for the volumes you mention. In this case their attraction is not the superior material properties but the relative ease of forming complex shapes that are otherwise just a bit too difficult for other fabrication techniques. Without the need for reflecting surfaces using LED, you can shrink the housing right down to be basically just offset from the lens surface - less material and weight. Certification is also basically a money problem more than anything - I think for lighting, there are engineering consultancies that can run your design through all the specific reflectivity/visibility/etc regulations for a sign-off.

Lots of additive manufacturing options now as well, not just for prototyping but fully functional/structural polymers and of course metals.

Hardly any road wheels are forged nowadays. Metallurgy and process engineering has come a long way since the 60's I guess.

[RWebb]

Thx Won.

Besides lighter tail light housings, I am still waiting for CF wheels and ceramic brake rotors for my '73...


I know they have the ability to 3D print in metals now, but how strong are they?

[Captain Ahab Jr]

SLS, or selective laser sintering is best for metals, titanium, inconel, aluminium are all used widely in F1/motorsport

Material properties are very close to billet properties but not quite there to be used on high fatigue components. Dimensional accuracy is also quite good, probably similar to diecast parts but again not quite there compared to machined parts,

Some F1 teams have been using SLS titanium roll hoops for over 10yrs and some team have used 3D printed parts for 20yrs

RWebb, let me know what size and offset you want your wheels in when sending me a large cheque and I'll have your CF wheels ready in about 6 months. An intern I worked with back in 95 designed and made a CF wheel for his Saab 99 for his final degree project. Your CF wheels would be my first!

[Won]

CF for road car wheels is pretty much a gimmick. Very little actual benefit vs. AL or MG, maybe you get more street cred. One of my previous companies (composites) did a study and prototype runs together with a well-known German wheel company whose name has three letters. End result: by the time the wheel met all the OEM requirements, there was hardly any weight savings. The only point they could sell it on was exclusivity.

Here is some info on commercially available printed metallic materials:
https://www.stratasysdirect.com/-/media/files/direct/material-datasheets/direct-metal-laser-sintering/dmls_titanium_ti-ti64_material_specifications.pdf
https://www.stratasysdirect.com/technologies/direct-metal-laser-sintering

[Captain Ahab Jr]

sssssshhhh Won, I'm trying to make a living here!

How is Mercedes going, did you choose the right dept. to work in?