V-Flash Printer and Intakes

[Mbirt]

I've been blessed with a faculty member who is eager to make me some intake parts on his new 3d Systems V-Flash printer. After checking out the basic provided material properties, I designed a "safe" post-restrictor diffuser that he'll make first.

The machine uses Film Transfer Imaging and "...demonstrate(s) stereolithography (SLA) like accuracy, resolution and quality." The FTI-GN material is said to be ABS-like and the basic material properties definitely match with ABS.

Information for SLA materials and ABS is available, but I'm having trouble coming up with anything better for FTI-GN. Does anyone have experience with it? It seems like the biggest problem in FSAE for RP intakes is backfires. We'll be certain to fit pressure release valve.

What it comes down to for me is the material's tolerance of gasoline and/or E85 for injector placement considerations. The intake runner will be exposed to fuel no matter how close we can get the fuel injector to the engine. It'll have to be coated with something like cyanoacrylate. I'm considering a narrow-spray high-mount injector mounted opposite the runner on the plenum. With proper internal coating, could this cause any problems with "SLA-like, ABS-like" material?

This is KU's first foray into RP, so we're not trying to waste anyone's expensive materials.

[Mbirt]

I've been blessed with a faculty member who is eager to make me some intake parts on his new 3d Systems V-Flash printer. After checking out the basic provided material properties, I designed a "safe" post-restrictor diffuser that he'll make first.

The machine uses Film Transfer Imaging and "...demonstrate(s) stereolithography (SLA) like accuracy, resolution and quality." The FTI-GN material is said to be ABS-like and the basic material properties definitely match with ABS.

Information for SLA materials and ABS is available, but I'm having trouble coming up with anything better for FTI-GN. Does anyone have experience with it? It seems like the biggest problem in FSAE for RP intakes is backfires. We'll be certain to fit pressure release valve.

What it comes down to for me is the material's tolerance of gasoline and/or E85 for injector placement considerations. The intake runner will be exposed to fuel no matter how close we can get the fuel injector to the engine. It'll have to be coated with something like cyanoacrylate. I'm considering a narrow-spray high-mount injector mounted opposite the runner on the plenum. With proper internal coating, could this cause any problems with "SLA-like, ABS-like" material?

This is KU's first foray into RP, so we're not trying to waste anyone's expensive materials.

[Mumpitz]

ABS like material properties, does that mean mechanical or chemical resistance or both? I think you'll have to do some testing or contact the company to answer that one. If it is questionable there are some vacuum infusion processes I've heard of for RP parts if they are porous, coats everything and makes it stronger and more chemical resistant. As for the mechanical properties... do I need to post a picture of the PVC wood and bondo prototype intake I made? Yeah it only saw dyno duty but the construction was barley on par with a 3rd grade art project. Schedule 40 is what? 1/4" wall if that?
Our SLS intake (not the same I know) withstood a dropped valve at 10,000 RPM that led to a snapped con rod that left a good bit of the piston blasting up into the intake. I just washed the piston and valve pieces out and slapped it all back together on a not as blown out engine.

[P. Jayaraman]

We've used SLA and SLS materials for our intake over the past three years or so and we've found that it works out pretty well, both in terms of structural strength and anti-corrosive properties.

With regards to the latter, we have our injectors mounted near the base of our runners (also made from RP material). This basically soaks the inside of the runner after a long run, but it has never caused any corrosion whatsoever.

One thing to keep in mind though is that a lot of RP materials become weaker under high heat conditions. We've been able to avoid this by adding ribbing to our plenum design as well as wrapping certain parts in reflective foil.

Just whatever you do, don't paint your intake black! We did that one year and our plenum imploded upon throttle closure at California. It was in the mid-90's that day, so we probably had that one coming.

[Mbirt]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by P. Jayaraman:
Just whatever you do, don't paint your intake black! We did that one year and our plenum imploded upon throttle closure at California. It was in the mid-90's that day, so we probably had that one coming. </div></BLOCKQUOTE>

I'm sure it helps that the whole thing is round, but... h t t p : / / media.global-formula-racing . c o m /2010/08/07/78/pictures/IMG_8300 . JPG

I saw a 3d Systems logo on the identical intake on their orange OSU car, but I'm not sure which machine/process and what their coatings, if any, are. I also believe that's a high-mount injector under the "Alphaform" logo.

Prashant, do you guys coat the inside of the runners and plenum with anything or have you run the parts bare? I've seen poor ratings for ABS in gasoline, but these pieces aren't submerged. And I've got no problem brushing some super glue in there.

John, that SLS plenum you guys run is pretty. I've got my all-steel 2.8 pound muffler mounted up on the '09 car and I'm anxious to get some dB readings here soon.

[Mumpitz]

Hysol has some good low-viscosity gasoline resistant epoxies that should be easier to work with than super glue.

I found that packing, trade-zies?
2.8 is impressive, I'm looking at close to 4 but it's stop gap plan that will get refinements as time permits.

[P. Jayaraman]

As far as I know, we haven't used a coating on the runners. I could be wrong on this though, I'll get a chance to confirm it in a few hours.

Also, I guess it would help to say that the material we use is a form of Nylon 12, so it already has some inherent anti-corrosive properties.

And touche with that black intake. I guess a lot of what happened to ours also comes down to where we placed it and how it's shaped.