Solidworks von Karman NC file?

[Tominator 2]

Hello everybody,
I am looking for a solidworks file for a 3D, 2 part mold for a 6:1 38mm Von Karman Nosecone. If somebody can send me the file that would be awesome.

Thanks,
Tom

 

[Eric1]

You have a CAD system, solidworks is a nice system.
So why don't you draw this yourself?
Your request seems odd.

Eric

 

[cjl]

It's easy enough to generate yourself. You can find the equations on wikipedia, so just make an equation-driven curve, then revolve it around an axis.

 

[GregGleason]

I couldn't tell if you had Solidworks or not, Tom.

It sounds like you may only need the file to pass it to a shop for fabrication.

As cjl has said, you can look up the formulas for VK NC's on the web. They are not that hard to muddle through. You can also use Excel to plot your X,Y coordinates into an ASCII file that your CAD system can process. You can then do a 360 degree revolve around the NC axis.

If you have Solidworks (or any robust CAD system for that matter) it shouldn't take that long to do.

Greg

 

[Tominator 2]

Actually, a friend has access now to a CNC machine so I wanted to ask around to see if any body has it already. Thanks for the replies guys.

 

[ClayD]

Actually, a friend has access now to a CNC machine so I wanted to ask around to see if any body has it already. Thanks for the replies guys.

Does a DWG work for you?

 

[jg inc]

shoot me an email if you need it. [email protected] i got a .SLDPRT file
like everyone said its pretty much straight forward.. gotta mess around with the way you enter the equation though.

 

[edwinshap1]

hey guys, i'm making the mold for tom. I was thinking that i could use some blocks of wood to create a 2 part mold for the nose cone, but i don't know how to use solidworks in that skilled of a way to split the mold in 2 pieces, each holding half of the nosecone.

if anyone can give me an explaination i can do it

 

[GregGleason]

hey guys, i'm making the mold for tom. I was thinking that i could use some blocks of wood to create a 2 part mold for the nose cone, but i don't know how to use solidworks in that skilled of a way to split the mold in 2 pieces, each holding half of the nosecone.

if anyone can give me an explaination i can do it

PM sent.

Greg

 

[rocketguy101]

It's easy enough to generate yourself. You can find the equations on wikipedia, so just make an equation-driven curve, then revolve it around an axis.

When I first saw this thread, it intrigued me as I have never used equation-driven curves at work on SWX (closest I get to is the helix for springs). I messed around and came up with this, using Gary Crowell's formulas--it took some algebra (via Maple ) to re-arrange the Haack equations into a single formula in x to inut to SWX.

Does the attached look right? After I completed the thing I realized when the OP asked for 38 mm, they probably meant 38 mm ID tube, so my dimensions are off, as the base of the nose is 38 mm.

Also, I found SWX doesn't like it when x=0 (probably a roundoff problem or their trig functions) so I used 0.001, meaning the nose has a minute flat spot on the tip.

 

[redsox15]

I also played around in solidworks when I saw this thread and found an equation for the von-karman but I must have typed it into solidworks wrong because the equation turned red which meant it didnt like my entry. What did your equation look like when you entered into solidworks?


Matt

 

[rocketguy101]

I also played around in solidworks when I saw this thread and found an equation for the von-karman but I must have typed it into solidworks wrong because the equation turned red which meant it didnt like my entry. What did your equation look like when you entered into solidworks?


Matt

I am running 2009 @ home...but it looks like this for the pictured cone...

19/2*(4*pi-4*arccos(-1+1/114*x)+2*sin(2*arccos(-1+1/114*x)))^(1/2)/pi^(1/2)

for a cone w/ a base dia of 1.64" (41.656 mm) it looks more complicated...

10.4140*(4*pi-4*arccos(-1+.8002048524*10^(-2)*x)+2*sin(2*arccos(-1+.8002048524*10^(-2)*x)))^(1/2)/pi^(1/2)

 

[rocketguy101]

I am running 2009 @ home...but it looks like this for the pictured cone...

19/2*(4*pi-4*arccos(-1+1/114*x)+2*sin(2*arccos(-1+1/114*x)))^(1/2)/pi^(1/2)

for a cone w/ a base dia of 1.64" (41.656 mm) it looks more complicated...

10.4140*(4*pi-4*arccos(-1+.8002048524*10^(-2)*x)+2*sin(2*arccos(-1+.8002048524*10^(-2)*x)))^(1/2)/pi^(1/2)

I think if you substitute the base dia f/ OD and the desired length f/ L, this will get you the same result:

1/4*OD*(4*pi-4*arccos((-L+2*x)/L)+2*sin(2*arccos((-L+2*x)/L)))^(1/2)/pi^(1/2)

 

[cjl]

When I first saw this thread, it intrigued me as I have never used equation-driven curves at work on SWX (closest I get to is the helix for springs). I messed around and came up with this, using Gary Crowell's formulas--it took some algebra (via Maple ) to re-arrange the Haack equations into a single formula in x to inut to SWX.

Does the attached look right? After I completed the thing I realized when the OP asked for 38 mm, they probably meant 38 mm ID tube, so my dimensions are off, as the base of the nose is 38 mm.

Also, I found SWX doesn't like it when x=0 (probably a roundoff problem or their trig functions) so I used 0.001, meaning the nose has a minute flat spot on the tip.

That looks about right to me. I know I've done it a couple of times before (but it's on a different computer than I am currently on), and I've never had a problem with going to a true sharp point, but I don't remember the exact details of what I did.

 

[redsox15]

I am running 2009 @ home...but it looks like this for the pictured cone...

19/2*(4*pi-4*arccos(-1+1/114*x)+2*sin(2*arccos(-1+1/114*x)))^(1/2)/pi^(1/2)

for a cone w/ a base dia of 1.64" (41.656 mm) it looks more complicated...

10.4140*(4*pi-4*arccos(-1+.8002048524*10^(-2)*x)+2*sin(2*arccos(-1+.8002048524*10^(-2)*x)))^(1/2)/pi^(1/2)

Thanks for the help. I was putting arccos in as acos. I watched a youtube video that said the equation input was similar to that of microsoft excel. Once I am back in the labs at school, I will try again.

Matt

 

[rocketguy101]

Thanks for the help. I was putting arccos in as acos. I watched a youtube video that said the equation input was similar to that of microsoft excel. Once I am back in the labs at school, I will try again.

Matt

I did the very same thing...it took awhile to find the proper math function names in the SWX help system...not sure why they didn't stick w/ VBA nomenclature.

 

[redsox15]

This is the equation I found to and works quite well and can be manipulated very easily depending on diameter and length wanted.

1.5*sqr((arccos(1-2*(x/14))-0.5*sin(2*arccos(1-2*(x/14))))/pi)

where 1.5 is the desired radius. In the x/14 portion of the equation change the denominator to the desired length you want to make your nose cone. So in the case above my nose cone has a 3in Diameter and is 14in long. NOTE: the length of the nose cone is not including the shoulder length. That was added on as another sketch/extrude. The link I got the equation/excel spreadsheet for the nose cone is:

https://www.verticallimits.nl/?page_id=222

Matt

 

[edwinshap1]

thanks, but at this moment i'm just waiting on for when my physics prof gives me a tutorial of how to turn solidworks files into the files for the CNC, then shows me how to program the CNC and calibrate it very fine.

Greg Gleason has sent a file that i cannot read at home, and have not yet had a chance to look at while at school. The image is of a 2 part mold, which when pressed together, can form a von karman nosecone mold.

i intend to make it out of some hard wood unless someone knows of a place to get hard pvc at 12x2x4" blocks