For whenever the 68 GTO complete CAD Model project begins
 

I've got the first piece ... 68 AM radio knob. Modeled in Inventor. "Life Size" CAD model, no scaling, mic'ed up an OEM piece.

Only 10,000 more parts to go ... so everyone start modeling :)

Good start would be finding the CAD models that the plastic model builders use to mold their models.

https://forums.maxperformanceinc.com...5&d=1671949270

67-72, headlight, wiper, lighter, radio, 8-track, and even B-body heater control.

Billet aluminum, but *without* the ridiculous bling?

https://forums.maxperformanceinc.com...1&d=1671949754

If you mean without the flutes and concentric rings ... probably pretty simple for someone that knows how to use a CNC lathe. With the bling ... jeez, probably five axis CNC work.

Actually the file I created for that knob (to 3D print it) would translate fine to CAM software for machining. Easy enough to remove the fancy features.

But, how to machine the notched hole for the stem on a radio I have no idea. Unless you just went with a round hole and added a tiny set screw for the stem flat. 68 of course were injection molded plastic ... and the older metal knobs were probably cast.

However if you want crude plastic knobs in various colors of the right size and shape I can provide those :) Or "custom" shapes, like hearts, moons and clovers :)

Here is a first attempt at printing one, I can do about 50% better, I was setup for printing "functional" parts at the time, not detailed parts. I'll spare you the details. The shiny black plastic did not photo well, I'll print out another before long in a silver plastic. Certainly not a piece a person would be proud to have in their vehicle ... but as opposed to none because a part couldn't be found ... it would work.

https://forums.maxperformanceinc.com...7&d=1671957695

Promising print; lighting? Flutes give style, but get dirty and tough to clean. Seems once i clean em, they stay rather clean.

Impressive! Nice work.

Messing with some TPU filament now. This material is commonly used in modern car bushing, bumpers, gaskets, "grippy" things etc.

Drew up this fuel pump gasket (from memory so not accurate) to test it. Basically a wonderful, flexible gasket. If you can draw it up in any CAD program that will export an STL file you can create any gasket you want, in any thickness. Add a sealing lip/ridge, change the bolt hole sizes etc. If you have a flatbed document scanner you can scan a gasket, bring it into a CAD program, change it the way you want and print them out by the dozen if you want.

This material is oil, grease and solvent resistant, Shore 95A hardness. In my opinion the max temp would be about 200 F, some say 210 F. So that would preclude it from being used in most engine applications where it comes into contact with the engine block. But, suitable for valve cover grommets, air cleaner fittings, HVAC gaskets, body gaskets (door handles etc.), various small bumpers, bushings such as sway bar, sway bar struts, shocks, vibration dampening, sealing washers, small weather strip pieces, elastic cable holders etc.

Tired of flimsy, ill fitting door handle, side mirror, key hole gaskets? Make your own. Need a slightly larger pull through bumper (console door, glove box door etc) draw one up and print it. Want robust HVAC gaskets instead of that totally crappy foam that is sold ... print your own. From about .030" to inches thick. Want to embed a washer into a bumper? (hood/cowl bumper) design the part with a cavity for the washer ... stop the print a the right place, insert the washer ... continue the print ... and produce a proper bumper with the encased washer.

Yes I'm kind of excited about this stuff :)

https://forums.maxperformanceinc.com...9&d=1672217193

For a while, some repro pedal pads were like hard plastic. I'm thinking grippy might not last 100,000 miles, but a wear item that you replace regularly?

Speaking of wear...

https://forums.maxperformanceinc.com...1&d=1672219656

That has to be a lot of fun! You are obviously keeping yourself occupied!

The CAD model is impressive. You've done this before.

The gasket ideas are a great use for a 3D printer. Good thinking!

I'm surprised you can print something that will hold up to 200F. That's quite impressive.

Have you ever messed with electroless plating? I know you have electroplated some parts. Are any of the 3D print materials conductive enough to electroplate?

I have also thought about ways to smooth out a rough 3D printed part. Maybe solvent vapors? We used to reflow solder with freon vapor before they learned we were destroying the ozone layer. Maybe tumbling in a fine abrasive slurry? Are there "commercial" solutions for this? I know the printer resolution is getting better but my zero knowledge suggested it was still difficult to print a mirror.

Fun stuff!

Do you use any 3D scanning software? You mentioned starting from files used to develop model cars. How hard would it be to scan a real part, generate a model, then clean it up in your CAD software? If it was relatively easy, your dream of building a CAD model for each of the 10,000 parts in your car could be closer to reality.

I'm ignorant but know there are many software tools that combine 2D scans/images of a part to generate a 3D model. For example, I have a Microsoft Kinect and PC interface. I know they have software to use it for 3D model generation. Might be fun to play with. I suspect there is way too much geometric distortion in a cell-phone camera but maybe not if you can "adjust" the imported model in your CAD world. To me, part designs back in the sixties and seventies were based a lot more on simple and "true" geometry (lines and arcs) than today where NC tools can follow geometries a lathe and mill never could. This might make it easier to make an accurate model as you did by direct measurement of your knob.

I always stop going down this mental path when I see the cost of CAD software like your Inventor....

Mike

I've been using CAD software for 20 plus years ... still a newbie really though, as I don't do it for a living.

You can at the moment print nylon, carbon fiber nylon, ABS, polycarbonate etc. for high temp products. Nylon prints at around 480 degree F and can easily live in an environment north of 300 F, ABS will handle 250+ F . Most of the filaments I use print at min 360 degrees F so their actual melting points are pretty high .. but degradation and creep will take place at lower temps.

Many filaments are available with carbon fill, copper fill, iron fill which does make them conductive .... so now you have cursed me with another project ... trying to electroplate something made of conductive filament ... which of course leads to chrome plated plastic.

Some filaments can be smoothed with an acetone vapor process ... basically suspend the item above a bath of acetone ... timing can be critical as the part surface can run if left too long. And most of the plastics will sand reasonably well. Most of the parts I'm posting photos of are printed in "draft" quality, not in the slower, higher definition modes ... which still isn't "smooth" but it's better than what I'm showing ... downside is it takes quite a bit longer.

I've looked into laser scanners ... problem is that a decent one is still about $5k. The Amazon variety for a few hundred appear to be very limited in usefulness other than for scanning the general shape. There are also high end probe type scanners that physically probe a part to generate the file ... but they have obvious limitations for cavities and hard to reach areas. Basically, if you have the money, it can be done and done very accurately .... a LOT of money. And yes this is often used for scanning in entire autobodies etc.

A lot of the CAD software I use is .... well, "obtained" and "cracked" by processes I'm not proud of. Spent a LOT of years on the internet, been around computers a long time, the stuff can be had, but considerable precautions must be taken if you don't want to end up with your PC under the control of someone in the former Soviet bloc or the software manufacturer disabling the software remotely. Back in the day the major CAD software companies kind of left open back doors to their software because they realized that in order to sell software that cost thousands they needed a user base, young people that could go into school already being familiar with a product ... who would encourage universities to buy hundreds of licenses for said software ... kind of like cigarette companies getting kids started early :)

But .... the good news is, there is very good stuff out there for free now, both the open source CAD/CAM software and things like Autodesk Fusion 360, probably the most widely used CAD/CAM software in the world .... and it's free. Autodesk gives it away, it does have some limitations but is perfectly usable for the hobbyist. And .. SolidWorks, the dominate CAD/CAM/Engineering software in the world ... you can get a student version (fully capable) for a subscription of $100 a year ... which I will be getting before long. Right now I use .. we'll call it "bootleg" versions of AutoCad, Autodesk Inventor, 3DS Max etc. for design work ... then import into legit Fusion 360 for CAM work. Which is why I want to change to the student version of SolidWorks ... can do all the design and CAM work in the same program.

Well, I'm definitely aware of the commercial world where cost is no object but hard to justify a lot of that stuff for hobbyists. CAD/CAM software is one of those. I'll look into the lower-cost options.. thanks for the info.

As to scanners, the cost of accurate laser-based and/or stylus-based digitizers is a barrier. That's why I was wondering if you had played with optical image-based scanners? They obviously would have lots of distortion but if they generated a model you could "adjust" in CAD, I'd think it would be affordable.

Being a met E I like metal parts and my professional life was made difficult many many (and many more) times by unexpected polymer properties.... but that's not the point. ABS is clearly a workhorse. Nylon absorbs water and changes properties so was never popular in my previous life when other "lubricious" options existed. Can you, for example, buy PTFE-filled ABS filaments for your printer (bushings, sliding surfaces)? I'll bet the carbon-fiber ABS options are pretty strong.

Cool beans on the conductive options. That knob needs to be plated. Just saying.

I've seen some fairly high-res "home-printer" parts that had good surface finishes. I'm sure the more you spend, the better the outcome. No surprise here but it's really great the world allows hobbyists to even do this stuff.

Keep having fun and sharing it!

The carbon fiber nylon is pretty good, helps a lot stabilizing it dimensionally and prevents creep under constant load. Nylon has to be handled carefully when printing it because it absorbs so much moisture, which then flashes to steam in the print head which creates a nylon foam :) So they have inexpensive "dryers" to store the spools and you can feed the printer right from the dryer.

Don't think teflon is possible ... in fact some printer "hot ends" actually have teflon in them, just way too high a melting point. Although .... as a particle composite like you suggest ... yeah, I'd say that's possible .... as it's done with tiny carbon fiber strands.

Basic list of what you can print with a sub $1000 machine.

ABS (and various filled variants)
PLA (quick easy, not suitable for most engineering requirements)
ASA (similar to ABS but with UV resistance)
PET
PETG (what I use most, prints easy, more impact and temp resistant than PLA)
PC (very clear, good to 150C )
PEEK, PEKK, ULTEM (require a high end printer)
PP
Nylon (numerous composite formulas)
TPU (which I use a lot, basically like rubber but better)

Tons of formulas out there for specific purposes and more coming out monthly. Now that 3D printing is being done commercially in the transportation, medical industry and such, the big chemical companies are getting involved and bringing their resources, I expect great advancements to be made in the available filaments.

When you think about it ... way easier to print something than create the molds and do injection molding. I'm absolutely amazed by what I can now do sitting right at my desk with the printer behind me. Don't even like to think about the thousands of hours I've spent designing some stupid bracket or spacer or something and then machining it. Now I can just draw it up (which I'd have to do anyway) and print it to within about .003-.005" accuracy.

Thank you

If you can print PEEK, you have a great option for underhood, electrical connector housings, wetted parts, maybe even solvent-wetted. Nice! But must be expensive!

PTFE would be amazing if you could print it but like you say, the low surface energy might not play well with the printer. I'll bet you can find filaments of PTFE-filled polymers with enough PTFE content to give you some good slippery stuff that won't suck water from the sky.

Interesting stuff, thanks again for sharing

For 2D geometries like the gasket in the first post, if you have a $200 copy/fax machine/printer you already have a scanner. Just lay the part on the copy glass and scan it to a thumb drive. Once on your PC, without too much effort you can convert the scanned image to a format (.jpg, .obj, etc.) that will load right into almost any CAD software in the 2D "sketcher" utility. If you know one dimension of the scanned part, you can scale the image inside the CAD to correct any errors and you are ready to 3D print any 2D object.

Yep, pretty much the way I've always done it. I typically scan at 600 dpi and then import the image into AutoCad and trace the lines in a drawing. Have no idea how AutoCad knows to do it, but the image is exactly 1:1 at 600 dpi when it's in the drawing window. So basically the accuracy is 1/600th of an inch. Use the various drawing tools to trace the image, extrude it to the thickness you want ... save as an STL file, slice it with the printer software and print.

Printed a 68 GTO rear hood bumper with an encapsulated washer. The repops don't have the metal washer in them so are basically useless, you but a screw in them and snug it down, it just pushes the rubber out of the way and you can pull it off the car quite easily by hand. The OEM pieces had the metal washer in them.

Here is the print paused so I can put the washer in place:

https://forums.maxperformanceinc.com...7&d=1672271894


Dropped the washer in place:

https://forums.maxperformanceinc.com...8&d=1672271899


Here the print is finished and you can see the washer encapsulated in the bottom of the bumper.

https://forums.maxperformanceinc.com...9&d=1672271912


Here is the printed part next to a repop .. the repop had to be trimmed down on the top because it was taller than the original OEM piece.

https://forums.maxperformanceinc.com...0&d=1672271920


Here is a cross section view of the CAD file show the cavity I put the washer in.

https://forums.maxperformanceinc.com...1&d=1672271927


Made some errors in the G-code for the print pause, next example should print out better. Also this has the wrong size washer in it, the washer hole should be smaller than the hole through the bumper ... didn't have the right washer in stock.

A persnickety person could print out bumpers just the right height to hold the back of the hood right where they want it :)

Sorry if I'm driving you crazy but I'm obviously intrigued by your projects.

That's a clever way to get an "overmolded" part. I'm kind of surprised the material will fuse to itself after pausing. How does this work? Does the new layer carry enough heat to "melt" the previous layer? Does the whole part need to be heated during printing?

Can you actually get some adhesion to the washer? Not needed in this application but I'm curious if you can get enough of a bond to stress the metal/elastomer interface without it coming apart?

How do the TPE material properties seem to compare with original rubber(?) parts? Can you get a range of durometers? Any info available to you about durability (ie cyclic stress, UV, chemical stability, etc.)?

OK, OK.... yes I should go look it up!!

Strangely enough, yes the adhesion after a pause is good, bear in mind the heated printing bed keeps the part around 120 F (or more if you want), the newly extruded plastic seems to melt right into the previous layers.

I'd guess you'd never get the bond to the metal that you would find with rubber parts, but it does bond to some degree .. depending on the filament used, as some of the filaments bond very well even to glass. I will put the parts I want to insert onto the print bed to warm up to the same temp as the print before I insert them.

As a print pause gets farther from the heated bed (Z axis) it can cause problems, but you can also specify the amount of cooling used on each layer to help compensate (on the print head there is a small cooling fan to help solidify the plastic after it extrudes to firm up the layer)

TPU printed solid is harder than typical rubber, Shore 95A, the resilience is controlled by the amount of "infill" used. In a cube for instance you can print anywhere from 100% (solid) to 1 % infill. The infill is a pattern of internal walls that support the exterior of the cube, many different pattern types are available. Also you can control the top, bottom and wall thickness to create a stiffer or more durable exterior surface. For instance on the hood bumper I had it print multiple top layers for abrasion resistance, multiple bottom layers for mounting point strength, and less layers in the walls to increase it's compressibility.

Attached is a photo of my selection of test cubes printed with varying levels of infill so I can get a tactile reminder of how infill effects flexibility before I design a part.

Info on UV and chemical stability is fairly easy to find, when it comes to things like abrasion resistance and tested durability you'll typically only find ratings like good, fair, bad etc. Much like the guidelines you might find on raw materials on McMaster-Carr ... however I'm sure the information is available from the companies producing the raw stock used to make the filaments ... but a lot of the filaments are custom formulations created by whomever is doing the filament extruding to enhance various properties ... usually with the goal of easier printing. You can for just a few thousand buy your own filament extruder and use raw pellet stock to produce your own filament :)

For bonding to metal, could you fake it with perforation? Print tiny little dowel pins, and laser cutter the washer. And with a laser cutter, you can make your own washers - think of how much $$ you can save. :D

No way I won't have a laser cutter within a couple of years :)

To lock things in better axially people will use a washer/part that isn't round, same principle as printing a hex shaped cavity for a encapsulated nut. People also use heat inserts which you heat up with a tool (like a modified soldering gun) and press into the plastic ... been used for years on manufactured plastic parts. Far as bonding as well as a bushing shell is bonded to the rubber ... I am unaware of a 3D printing process that would do that .. but then my knowledge of the process is limited.

I know it's being used more and more, exotic cars often have 3D printed parts, speeds prototyping and makes production of a very limited number of items more economical. Makes design changes much easier .... literally a matter of hours.

There are now numerous "Printer Farms" .. facilities with dozens of high end printers, you just upload your designs and they print them in high quality engineering plastics, much like a production machine shop. Ferrari is big into 3D printing in both composites and Metal.

I will be opening the Church of 3D shortly :)

Forgot the photo my "test cubes" for TPU filament ... each one printed at a different level of flexible .... I just grab one and squeeze it in a scientific way to determine if it will be right for the job :)

https://forums.maxperformanceinc.com...8&d=1672400975

Tnx for all the insight. Must be fun for you. You're learning a lot!

Just watched a video from a guy that electro plates plastic ... looks fantastic. He paints them with a conductive paint, plates them in copper .. quite thickly, and then brush plates them in palladium. They come out looking outstanding. All done in a "at home" method, nothing industrial required.

3D
 

Interesting topic.
I've had 3D Printers in my toolbox for the last 20 years or so.
In fact, I just took delivery this week of my 3rd one.
Check out this monster

Car Parts
 

Tri Power End Carbs. One is modeled and printed as 3 separate parts- baseplate, body, airhorn. The other is printed one piece.
These were done about 10 or 15 years ago on a Stratasys Dimension FDM in ABS.

Car Parts
 

Here's another set of end carbs

Be interesting to 3D print a factory RA V head.John 3D scanned one of mine when we were doing the Bathtubs.Tom

Car Parts
 

Here's an air cleaner lid on an LS6 in a Z28 done in Nylon 12 Carbon Fiber with a Fortus 450mc FDM.
It was tough getting the Victor/Dominator/NOS Plate under the 4" Cowl hood even with a drop base. No way it would've fit without the custom contours.

Car Parts
 

Here's another car with a 3D Printed PCV Valve Extension in the Valve Cover.
It also has some 3D Printed Spark Plug Wire Separators.
I think probably every car in my shop has a set of these dressing the wires.
In fact, I just ran off another set this afternoon for a 455 that is going in my 66 GTO.

Car Parts
 

Another set of Spark Plug Wire Separators on my L71 427 Corvette

Panhead
 

Panhead

Materials
 

I've worked very closely with the major players and materials manufacturers in the industry to develop some pretty exotic materials with very specific properties.
Antero 840CN03 was my baby. That material is PEKK based with carbon nano-tubes.
It took a lot of years to get that material to work.

I did the same with the company in Germany that built my latest acquisition.
The new HT25 material is going to blow some people away.
Very high strength high temperature with enhanced thermal and electrical conductivity.

Currently working on some very unique next generation stuff.

Tom, I could print a functional RAV intake that you could bolt on your car & run.

MC Parts
 

This was a MC License Plate Bracket

Carbs
 

Carbs

CAD
 

CAD

Last one
 

Last one. This MC was almost entirely 3D Printed. And you could ride it (had an electric motor)

Very cool!

How about a 1970 Formula Firebird?

:D

3X ... so with the carbs .... they are functional? And hold up under various types of fuel?

Were they modeled from scratch or were original blueprints available?

I'd love to know the specs of a large modern printer ... print speed, nozzle temps, nozzle size ... assuming they even spec things the same way as hobby printers do.

Very interesting stuff, additive manufacturing is in my opinion is the future, so many advantages over conventional machining. The technology is going so fast it's hard to keep up with.

Those carbs were done in ASA on an FDM machine.
ASA material is basically ABS- not compatible with gasoline.
And FDM technology is porous without some post-processing work.
I was just goofing around one day and modeled them up because I was missing a set of end carbs for a spare Tri Power I had kicking around.

I subsequently modified the design slightly for one set because I was considering printing some in metal using DMLS and using them as throttle bodies with a set of fuel injectors replacing the NOS fogger nozzles I had in the cast iron '65 manifold.
I could've also done those in another polymer material that was compatible with gasoline though.

You can look up the specs of my old Stratasys Fortus 450mc FDM online. High temp materials extrude as you can expect at pretty high temp- approaching 800F. And the chamber temp is accordingly very high- over 300F. Nice machine. Run you about $250K though.

One problem with that FDM technology is soluble supports are liquified at those high temps- so you are forced to use breakaway supports- which can be problematic and time consuming to remove.
And the layer resolution with the high performance materials is only 0.010".

My latest acquisition is SLS Polymer powder bed fusion technology.
No supports required for exotic high temp materials.
Also isotropic strength & 10X faster builder times.
My first beta samples parts that used to take 3 hours to build on the old FDM platform now build in 20 minutes.
Price of admission for that bad boy runs north of $.5M+
But if you're savvy with the numbers, and you want to look like a hero for the company you work for- just do a cost benefit analysis showing the payback.

I submitted a very conservative CBA with a $650K CER showing a <6 month payback- on just a couple small parts.
Approvals came back almost immediately when you show $1M+ savings annually.
Lot of smiles.

In fact, I already have FY 23 budgeting in place to purchase another new machine.
Top secret discussions though- ground breaking technology.
I have NDAs in place so I can't talk about what I'm doing yet.
All I can say is it's DMLS based (metal) and kick-ass.

Sweet, I would have loved to go in that direction with a career. (that shipped has sailed, I'm retired now). I think additive manufacturing will have the same impact on manufacturing that CNC did. Would be a smart investment right now to buy into some of the leading industrial level machine manufacturers.

Some of the things I've already seen with metal printing are game changing when it comes to designing components .... saw an amazing liquid/liquid heat exchanger for helicopter hydraulic fluid that was 1/4 the volume, 1/2 the weight and about 40% more efficient than the tube type it was replacing ... it used some kind of fractal geometry for the exchange surfaces all inside a one piece unit. Ferrari has said the recent successful F1 engine used 3D printed pistons.

Any suggestions for a good industry news website I could watch to keep track of the technology?

Any suggestions for a good industry news website I could watch to keep track of the technology?[/QUOTE]




Johnny if you haven't already found it, check out the Additive Manufacturing/3D Printing sub-forum on the Practical Machinist site.




Dave

X4, fun to see the amazing progress in both hobby and commercial 3D.

As to boats sailing... my casual interest is now just that, but my boat could have sailed into 3D printer development, so it holds the attention of this nostalgic retiree.

At one point in my life, I developed a non-wetting coating process for the face of ink-jet nozzle plates. That project was truly challenging, fun, and rewarding. I learned a lot from many talented people back then and miss those days.

When that employer told us "We don't like your kind" (manufacturing was leaving the country) I was sent packing and chasing jobs like a lemming following a nerd herd.

Punch line- I interviewed with Stratasys in about 1993? when they were young. They needed help keeping their "nozzle plates" clean, same as ink-jet. I ended up on a different path but remain intrigued by 3D printing. Maybe I'll get into it on the hobby side one day but for now, I enjoy seeing all the stuff you're both sharing. Thanks for posting, even if it's a Pontiac forum...

Dave ... I book marked that forum ... but sometimes I hesitate to go there, at least for machining anyway, they tend to be a bit rude to the uninitiated.

Shiny ... ink jet printers, as you know have some amazing technology that makes them work. Incredibly the price they sell for considering what went into making them work. I like to scavenge parts from them, like the rod the head travels on ... extremely straight, and extremely round.

Yes, I could see those rods being useful. There are lots of great scavenging opportunities in discarded/obsolete products. Magnets from hard drive actuators are pretty amazing... I worked in that industry too and it was by far the most technically amazing product I was exposed to. You can develop some incredible stuff when the cost is spread over billions of products. Integrated circuits set the bar there...

If the market for hobby 3D printers was as big as it used to be for ink-jet, we'd all be printing eggs, meat, and vegetables while complaining about the cost of the print cartridges!

I have a half dozen notes held to the metal bookshelf behind me with HD and optical drive magnets :)

I can print a banana ... but you can't eat it. (should be the title of an album)

We are scroungeanized... like a parallel universe, only different.

I worked on both HD and optical drives (ODD)... the magnets in HD actuators are worth the effort. HD actuators are rotational and the magnets are STRONG rare-earth stuff.

The pickup head in an optical drive rides little rods like in the inkjet printers (linear). You might also like those rods as they have high precision similar to the inkjet traverse rods...very much like your CNC machine linear actuators.

Not much else scroungeable in those devices. Motors might be useful but not easy to adapt for general purpose.

Stratasys does a lot interesting webinars. If you go onto their website you can check it out and get registered and they'll email you latest news & developments in additive. Lot of interesting articles.

Stratasys Direct is another independent division that does contract work- they'll build your parts for you on any platform or technology you like. Online quoting. Great pricing.

I've just started reviewing resumes of local university ME Students this week for an internship opportunity. Just in case any one knows any students near the NH Seacoast looking for a great job working in CAD mechanical design, 3D Printing and using Ansys simulation software.

You guys talking about inkjet probably already know, but if you don't- check out HP Multi-Jet Fusion Technology. It's very popular and produces excellent quality durable parts. Somewhat limited in material choices though. Their voxel control has great potential.

One of my old inkjet colleagues went on to help develop that HP technology. I lost touch with both him and additive tech but I know he was quite pumped about it several years ago. Sounded like it could deliver some unique properties with high resolution and I'm sure the software environment, integration, and support are part of the value proposition. I'll have to go look at it. Thanks.