Jadz928

No doubt, great curves. But essentially very simple. At least from my point of view and how I would lay it out. The over all form is not the bugger... like I said, it's the details.

Re ABS material for3D printers. I wasn't aware there is such a thing. There are resins that mimic the feel and strength of ABS, but don't carry all it's essential properties. Being that resin is mainly a UV "cured glue", they can only get it so close. DMX100 is the closest I've found, but has major tendencies to creep and not hold it's shape well, under it own weight. It really depends on the application, though.

If you really want rugged prototypes, you need an SLA pattern to Silcone molds to Urethane casting. This is a great process I've used many times. Pricey but effective.

PorKen

I use Inventor (2008), too, but I haven't progressed much past the sheet metal toolset.

I would like an accurate measurement of the center of all the timing belt pulleys to each other. Specifically: cams, crank, water pump, oil pump, and water pump idler pulley centers. I'd be willing to make a quick 3D model of all of those. I might even be able to make it move!

What I want it for is to model the belt lengths between the gears, so I can make a variable valve timing system, to at least make it easier to find the optimum cam timing on the dyno, if not a dynamic system.

JEC_31

Everyone remain calm while the thread hijack runs it's course. No harm to Mike's thread intended.

We have a Stratasys Maxum FDM (Fusion Deposition Modeling) machine.

It takes in raw material (their very proprietary ABS) in wire/strand form from a very expensive spool that has a chip embedded in it to tell the machine how much material is left.

It sucks the fragile wire of plastic up into it's extrusion head, which is riding on an air bearing on the roof of it's chamber - which is a magnetic grid. The head contains a "forcer" that drives it around the grid according to the machine's CNC control. The head extrudes a bead of molten plastic along a 2D path onto a clear acrylic sheet held to a movable horizontal platen with vaccuum. The ABS cools quickly as it's extruded.

When it's done with the first layer, the platen drops exactly one layer height and the head lays down the next layer. So it builds the up model layer by layer. The chamber is held at a certain operating temp so the cooled ABS is still tacky enough to quickly accept the next layer and they fuse as it's deposited: Fusion Deposition.

The real magic is the second head and the second spool of a different material, a super-thin and brittle sugar-based polymer. This stuff is laid down where the ABS isn't - but will be in a higher layer. It's simply "support", so that undercuts can be made without the hot ABS strand simply spewing out into a mess as it cools in the air. And more than undercuts: it will fill in any gaps in the CAD model with the support material. Using this feature we can make working assemblies with gears, etc. When the job is done, this material easily breaks away from the ABS or is dissolved from hidden crevices in a sonic cleaning tank filled with water and StrataSys's special solvent.

We love it because we're auto-industry injection molders. We need hard and durable prototypes to use for stand-ins during the accelerated process development timeframe, when we have ppl busy building assembly, chrome-plating, and painting equipment long before the ($$$ + time!) injection mold is finished. This pays off immensely because when the mold is finally done and making real parts, all the downstream processes are ready and waiting to be fine-tuned - and our customers are chomping at the bit to get pre-production samples to slap together test cars. They do love our shiny chrome grilles.

We also do a lot of test-and-tune parts for our designers, snap-fits and what-if parts. And of course, we make a lot of show-and-tell parts for the sales guys to take to meetings with customers. At least once a large automaker has bolted one of our FDM grilles to a test mule and run it around the European backroads.

The finished parts have an odd texture to them from the layers, and are too porous to get our chrome plating on (although we're working on that!), but they are dimensionally good down to ~0.05 mm (I've measured a few).

I would not recommend buying one of these FDM machines without a service contract (~$30K+) unless you are gifted at working on them already. Also, invest in a big battery back-up as a simple power blip can kill the machine. Each forcer head is ~$14K+, for example.

End thread hijack.

- Josh

JEC_31

I could do that if I had an assembled (and dry!) engine available to use in West Michigan...

backnblack

Hello Mike I apologize I kinda feel this may be directed to me and the crank pulley. I did appreciated you sending me the file ( from what I can remember you where offering it to DRninck ) I know you don't know me but I figured you don't know until you ask but I didn't here from you for a while so I almost had it all finished by the time you sent it to me, again I did appreciate it I'm sorry if you felt that way.

Regards
Matt
BTW I do 3d modeling Raipd Prototyping

piccardo

Well I am interested in making a solid model of the body. I have some photogrammetry software now and will be doing some experiments to determine how acurate it can be. If this works fairly close I intend to import the data into inventor to add the details and such.