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Topic: Car Exhaust Stub

I have a cool little car (Suzuki cappuccino), and it has these little side vents in both the front wings. They have been begging to me to replace them with exhaust stubs like a Spitfire/P51 Mustant has.

So I prototyped one up, and failed miserably on the last hurdle, the stub points up at 45 degrees rather than down the side of the car. roll

Here are some pictures:

https://lh3.googleusercontent.com/-XaxGdzL61_M/ULxh_OyeMHI/AAAAAAAAAtA/Vykd3Bqz0OI/s1152/IMG_5371.JPG
https://lh6.googleusercontent.com/-MOi6AO4rCEM/ULxh-6yG-sI/AAAAAAAAAtA/Sw8Ekddi5V0/s1152/IMG_5372.JPG
https://lh6.googleusercontent.com/-0CRPIE6HLVg/ULxiAAwlX8I/AAAAAAAAAtA/q0zXLFCqvHg/s1152/IMG_5373.JPG

This is after a series of sandy, spray on automotive putty, then chrome paint. I will record the process on the next one I make.



To get the silhouette of the vent hole to create the fitting. I simply removed the original plastic fittings, placed them on a scanner. Scanned in at A4 size. Within 3DS Max created a plane to the same size as an A4 sheet of paper. Applied the scanned image as a texture, than created a spline around the outline of the fitting and extruded it to get the correct fitting shape and size. Printed a simple test ring of the correct depth to make sure it fit, and it did first try! smile

Lead Programmer & Co-Owner of Camshaft Software - Creators of Automation - The Car Company Tycoon Game

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Re: Car Exhaust Stub

Looks cool.  Interested in seeing the finishing process for sure.

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Re: Car Exhaust Stub

So attempted another print, but the scaffold lifted off. So I modelled my own brim and printed it again.

Here are the results:

https://lh4.googleusercontent.com/-QEszmiAsX1c/UMGxCNkyQdI/AAAAAAAAAvA/Snv6doXe7wQ/s1152/IMG_5374.JPG
https://lh3.googleusercontent.com/-u3nqNHemm64/UMGxCI71rNI/AAAAAAAAAvA/4C00vmor61Y/s1152/IMG_5375.JPG

The underside showing my own brim:

https://lh3.googleusercontent.com/-6bIMJmzLDp0/UMGxB_ha-QI/AAAAAAAAAvA/dFbpjGUxJbg/s1152/IMG_5376.JPG

Close up of where it lifted up, I think due to some contraction of the scaffold:

https://lh4.googleusercontent.com/-qN9KQSIBApw/UMGxQrb4OdI/AAAAAAAAAvA/JHnyPfjhUwE/s1152/IMG_5377.JPG

Scaffold closeup from the side:

https://lh5.googleusercontent.com/-vkbDbHoIuDo/UMGxWwt4swI/AAAAAAAAAvA/3G909TEYajk/s1152/IMG_5380.JPG

Close up of the top

https://lh5.googleusercontent.com/-iQHFAAeQPLg/UMGxQo7xLPI/AAAAAAAAAvA/yD4M8JYAUxY/s1152/IMG_5378.JPG

Really happy with the print quality of the sides, after some calibration setup on the extrude rate from the slic3r wiki

https://lh4.googleusercontent.com/-T8AkAUxHvTY/UMGxSRPVBPI/AAAAAAAAAvA/AYFRkXJdlYw/s1152/IMG_5379.JPG

A view from the top after some sanding, it needs quite a bit more. Also I want to see how this 'silver' filament comes up with some very fine 1200 or 2000 grit sand paper

https://lh6.googleusercontent.com/-ZUnAu0Zv12s/UMG6GqQK9mI/AAAAAAAAAwU/5gKz03HWwvs/s1152/IMG_5382.JPG

Finally testing on the car:

https://lh4.googleusercontent.com/-px20I11nEJg/UMG6HXKJHyI/AAAAAAAAAwU/wXCFRaNs-NM/s1152/IMG_5383.JPG

https://lh6.googleusercontent.com/-arrveFf-xsg/UMG6VYtfP4I/AAAAAAAAAwU/lLr2ifedtg8/s1152/IMG_5386.JPG

Lead Programmer & Co-Owner of Camshaft Software - Creators of Automation - The Car Company Tycoon Game

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Re: Car Exhaust Stub

lol.. very cool

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Re: Car Exhaust Stub

Here they are, all done and complete:

https://lh6.googleusercontent.com/-URB-k25jttA/UMln69Q15uI/AAAAAAAAAxI/WGn40LRRH4Y/s1440/IMG_6606.JPG

Lead Programmer & Co-Owner of Camshaft Software - Creators of Automation - The Car Company Tycoon Game

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Re: Car Exhaust Stub

came out looking real good congrats !

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Re: Car Exhaust Stub

Very nice Caswal.  Any chance you can detail your finishing procedure and show some closeups of the parts finished.

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Re: Car Exhaust Stub

nice, that came out great. What were your settings for support material?

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Re: Car Exhaust Stub

cmetzel wrote:

Very nice Caswal.  Any chance you can detail your finishing procedure and show some closeups of the parts finished.

I have another part I am going to do, and detail the whole process. If you look at my door mirrors, they are missing their clips to hide the bolts that hold them to the door. I have one but not the other. So I will print 2 to replace both of them.

My process is:

  • Print object at 0.3mm

  • Remove Support using one of those art scalpels

  • Sand back with 240 grit sandpaper, smooth the worst of the layering out

  • Use a dremel with sandpaper roll for some of the more hard support material clinging on

  • Coat with 3-4 coats of Automotive Spray Putty (Leave only 5-10 minutes between coats, than an hour or 2 to dry)

  • Sand back using 240 or 320 grit to get all of the layers out

  • 1 - 2 Coats of Filler Primer (Only 5-10 minutes between coats)

  • Another quick sand of 320 or 360 grit

  • 2 coats of base matt black

  • Spray of Graphite colour

  • While wet, a light flourish of silver

  • Final spray of matt black on the rear of the vent to give it a soot look

Although the process sounds laborious, it is not really that bad. Probably per vent is about 20-30minutes of sanding, and the rest is just a lot of waiting while the different coats dry. I'm still amazed at the ability to produce items like this at home now.

McMuFFin wrote:

nice, that came out great. What were your settings for support material?

Pretty standard Slic3r settings, distance dropped to 2.25mm rather than 2.5mm, and modelled my own Brim. that seems to help immensely. As it lays down the brim with normal solid infill settings. Then sticks the support onto the top of that. I have not had much luck with the auto generated brim.

Lead Programmer & Co-Owner of Camshaft Software - Creators of Automation - The Car Company Tycoon Game

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Re: Car Exhaust Stub

You might want to give the vapor bath a try after an initial rough sanding.  It could save you a few steps.  You can knock down the layers quickly with something rough like 100 grit.  Brush off the biggest particles, and let the fine dust help fill the cracks.  After 30 seconds in the vapor and a 40 minute dry out, you might be ready to go straight to the paint.

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Re: Car Exhaust Stub

Using acetone and a paintbrush on the exterior would smooth that all out if you dont have the vapor setup yet.

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Re: Car Exhaust Stub

From my experimentation with acetone, I felt that it would not smooth out the contours that much. If you look at the picture straight down, it has about 4-6mm wide contour bands to smooth out. With my sanding with 240 grit which was plenty course to quickly smooth the worst of it out, I was starting to get on the edge of wearing through places to get it to a smooth finish. With thicker perimeter settings it probably would of worked.

Putty is also quicker to smooth out than abs, and easier to work with. That is what it is designed for. In the summer heat here, only takes a few quick coats, and about 40 minutes drying time before it is all workable.

Lead Programmer & Co-Owner of Camshaft Software - Creators of Automation - The Car Company Tycoon Game

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Re: Car Exhaust Stub

That looks really. great and good to see real world mechanical parts being made too. I know we all get hung up in the 3d world printing millions of cal cubes, test, and more parts for our printers. But just using a printer as the tool/workhorse it can be to make functional real world parts is so satisfying.

I am printing a party cooler setup and speaker enclosures. And just making real parts for it and it is great.

Any more closeups of the final print to see the paint finish  & quality?

SD2 owner- Surestepr, filament holder,QUBD servo and heaters, glass bed
Print for fun and for parts for my sports cars
current car is 88 IROC