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Re: 3 -D printing
Posted: Wed Nov 15, 2017 11:39 am
by GARY C
Yes I have seen the house one, I think 3D printers are cool but it wouldn't be for me, I still use my phone for phone calls and a map to figure out where I am going.
Re: 3 -D printing
Posted: Wed Nov 15, 2017 3:04 pm
by digger
Cheap printers are pretty crap if you want to do anything more than mock up
Re: 3 -D printing
Posted: Wed Nov 15, 2017 3:10 pm
by Dave Koehler
digger wrote: ↑Wed Nov 15, 2017 3:04 pm
Cheap printers are pretty crap if you want to do anything more than mock up
Tell us of your experience with cheap and which units did you try?
Re: 3 -D printing
Posted: Wed Nov 15, 2017 3:26 pm
by gnash
Dave Koehler wrote: ↑Wed Nov 15, 2017 3:10 pm
digger wrote: ↑Wed Nov 15, 2017 3:04 pm
Cheap printers are pretty crap if you want to do anything more than mock up
Tell us of your experience with cheap and which units did you try?
I have not had a good experience with acrylic frame printers. I just could not get the frame squared-up in all axes.
Rumor has it that the Creality CR10 is a great starter printer. When they first appeared you could get one for about $350.
3D printing is like cooking. You can have the best hardware, software. But it takes a lot of experience to get everything else right.
Re: 3 -D printing
Posted: Wed Nov 15, 2017 3:54 pm
by SchmidtMotorWorks
GARY C wrote: ↑Wed Nov 15, 2017 12:17 am
SchmidtMotorWorks wrote: ↑Wed Nov 15, 2017 12:08 am
I have printed 3 complex intake manifolds in the past 2 months.
It takes about a week to print one V8 manifold with a good printer and it is expensive.
A manifold is good for about 20 dyno pulls and it takes a lot of prep to get one sealed enough to run.
I am putting together a single cylinder engine and dyno now with a TFX pressure measurement system so that I can make single runners on the CNC in urethane instead of printing.
Are you able to do them transparent enough to see fuel distribution? I recall seeing one done a few years back that was made in 2 parts and then bolted together for easy porting and modifying and it was simi transparent.
Maybe but I doubt it would be practical.
After this last set of manifolds, I say the time and money spent would have been better invested in CFD simulation effort and single cylinder engines before anything V8.
Dyno testing just doesn't return enough information to make decisions with.
Re: 3 -D printing
Posted: Thu Nov 16, 2017 3:20 am
by digger
Dave Koehler wrote: ↑Wed Nov 15, 2017 3:10 pm
digger wrote: ↑Wed Nov 15, 2017 3:04 pm
Cheap printers are pretty crap if you want to do anything more than mock up
Tell us of your experience with cheap and which units did you try?
had a mate that used to do ABS basically 'toys' that had less than ideal infill so cracked after a while, i now use a professional place (machine probably costs 200x the cost) and get either Nylon12 or Alumide. the stuff is actually usable if temps are reasonable but if generating huge clamp load under bolts then gotta spread load to avoid creep/relaxation. it costs more than mates rates but its not too bad if you shop around and you know how the price is calculated you can design around that sometimes
Re: 3 -D printing
Posted: Thu Nov 16, 2017 3:23 am
by digger
SchmidtMotorWorks wrote: ↑Wed Nov 15, 2017 3:54 pm
GARY C wrote: ↑Wed Nov 15, 2017 12:17 am
SchmidtMotorWorks wrote: ↑Wed Nov 15, 2017 12:08 am
I have printed 3 complex intake manifolds in the past 2 months.
It takes about a week to print one V8 manifold with a good printer and it is expensive.
A manifold is good for about 20 dyno pulls and it takes a lot of prep to get one sealed enough to run.
I am putting together a single cylinder engine and dyno now with a TFX pressure measurement system so that I can make single runners on the CNC in urethane instead of printing.
Are you able to do them transparent enough to see fuel distribution? I recall seeing one done a few years back that was made in 2 parts and then bolted together for easy porting and modifying and it was simi transparent.
Maybe but I doubt it would be practical.
After this last set of manifolds, I say the time and money spent would have been better invested in CFD simulation effort and single cylinder engines before anything V8.
Dyno testing just doesn't return enough information to make decisions with.
with a manifold design (with distribution issues etc) how much is a single cylinder representation gonna tell you that a 1D sim wont?
Re: 3 -D printing
Posted: Thu Nov 16, 2017 11:25 am
by mekilljoydammit
Just to chip in my own two cents, one thing you can do with even a 3d printer that only handles the basic plastics is use it for investment casting patterns.
... of course, then this gets into a topic about home foundry stuff and not just home 3d printer stuff.
Re: 3 -D printing
Posted: Fri Nov 17, 2017 10:03 am
by jmarkaudio
statsystems wrote: ↑Tue Nov 14, 2017 11:31 pm
jmarkaudio wrote: ↑Tue Nov 14, 2017 9:20 am
I've done some small carb parts, pump cams and vent whistles.
Are you making custom pump cams or just copying Holley stuff?
No, I used a pump cam in a scanner to get the basic starting shape. I then sketched a vector image over it in Illustrator, making mods where I wanted to. Then imported the dxf file into Fusion 360, extruded the pieces from there.
Couple others I drew by hand.
Re: 3 -D printing
Posted: Fri Nov 17, 2017 11:40 am
by SchmidtMotorWorks
digger wrote: ↑Thu Nov 16, 2017 3:23 am
with a manifold design (with distribution issues etc) how much is a single cylinder representation gonna tell you that a 1D sim wont?
It depends on what you mean by distribution issues.
The engine I am working on now is fuel injected after 0.01 seconds of open throttle, distribution has not been a significant issue.
Having completed the last series of manifolds dyno tested them, modified them and dyno tested again through 2-3 more cycles of experiments, I end up with recipes but not understanding of exactly why some features caused the changes they did.
Given the cost and time of that process, I will put much more effort in 1D and 3D simulation on the next series of experiments to have a better understanding of why things work the way they do.
The way I see things now; there is substantial opportunity to optimize runner design with non-linear cross-section designs.
My current list of variables is about 8, on a V8, that is just impractical to prototype and test. At the rate I am going that would get into the $ hundreds of thousands and the project would not have positive ROI at that price no matter what is discovered.
Re: 3 -D printing
Posted: Fri Nov 17, 2017 4:50 pm
by digger
SchmidtMotorWorks wrote: ↑Fri Nov 17, 2017 11:40 am
digger wrote: ↑Thu Nov 16, 2017 3:23 am
with a manifold design (with distribution issues etc) how much is a single cylinder representation gonna tell you that a 1D sim wont?
It depends on what you mean by distribution issues.
The engine I am working on now is fuel injected after 0.01 seconds of open throttle, distribution has not been a significant issue.
Having completed the last series of manifolds dyno tested them, modified them and dyno tested again through 2-3 more cycles of experiments, I end up with recipes but not understanding of exactly why some features caused the changes they did.
Given the cost and time of that process, I will put much more effort in 1D and 3D simulation on the next series of experiments to have a better understanding of why things work the way they do.
The way I see things now; there is substantial opportunity to optimize runner design with non-linear cross-section designs.
My current list of variables is about 8, on a V8, that is just impractical to prototype and test. At the rate I am going that would get into the $ hundreds of thousands and the project would not have positive ROI at that price no matter what is discovered.
i was thinking you had common plenum similar to single plane manifold
i'm using 3D printing to do some IR runners where packaging constraints are problematic and i need a slight curve shape similar to the S54 engine. 3D printing is bar far the cheapest way i know of doing a small batch of 6 when you value you own time (ive hand glassed then before but takes ages). i did some crude CFD in fluent to get flow trajectories about as uniform as possible at the outlet. i can input the size at various positions along the length in engmod4t but the slight curve isn't captured
Re: 3 -D printing
Posted: Sat Nov 18, 2017 12:44 am
by SchmidtMotorWorks
digger wrote: ↑Fri Nov 17, 2017 4:50 pm
i was thinking you had common plenum similar to single plane manifold
i'm using 3D printing to do some IR runners where packaging constraints are problematic and i need a slight curve shape similar to the S54 engine. 3D printing is bar far the cheapest way i know of doing a small batch of 6 when you value you own time (ive hand glassed then before but takes ages). i did some crude CFD in fluent to get flow trajectories about as uniform as possible at the outlet. i can input the size at various positions along the length in engmod4t but the slight curve isn't captured
They are forward facing throttle body manifolds for the Coyote engine.