chine line?

[HO-229]

Good day all,
Problem statement:
Wish to sketch a 3 dimensional line/datum line; I am trying to establish the steps to achieve the aforementioned. I desire to sketch the chine line of a hull so I can loft geometry utilizing the path and use it as a reference for section data; can someone please point me in the correct direction?
I have sketched the top plane conic(s)
I have sketched the profile plane conic (s)
How do I tell pro-e to make the aggregate lineof the two conics/lines?
(trying to expand my tool box)
Thank you in advance,
Dave
Edited by: HO-229

 

[cpoirier]

Use the intersect command.
Edit>intersect
The secret pro-e hand shake that makes it work is to have one of the sketches pre-selected.

The programers at PTC don't know how to write tools to both lead/follow and have had the word intuitive surgically removed from their vocabulary for the sake of hidden simplicity.

Having said that I still love Pro E because once you get used to it and get some time on it you start to think its efficient...... but still a pain in the butt and a bit backward.

Chris

 

[HO-229]

Thank youChris,<?:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><O></O>
I'll give it a go and see how it works out; being a AutoCAD user for some time I have been slowly unlearning a bunch of things.<O></O>
The tool box is way more powerful and productive... my biggest challenge with pro-e has always been interpreting all the cryptic menus and steps processes associated with a task.<O></O>
If I stumble I may PM you for assistance if that is acceptable

Chris,<?:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><O></O>
If I do not have a solid to project the two sketches onto will this method work?<O></O>
<O></O>
<O></O>
Dave

<O></O>



Edited by: HO-229

 

[cpoirier]

OK, no solids needed, no surfs needed either.
Here are two ways I think you may be able to get going on this.
This is my best 10 min attempt.
See the file attached.
You can use model player to see how it was done.View attachment 5444

Chris





2011-11-21_084746_test.prt.rar

 

[HO-229]

Thank you for that data Cpoirier,


I was on the right track but did not full understand the way to get there.


May bend your ear about constraining the end points of a datum curve if you could offer some insight... all three axises.


briefly sketched a complex curve with dataum curve but did not have time to sort out the proper way to constrain the 3 axis(start point and finish)


Thanks again,


Dave

Edited by: HO-229

 

[mechdes1a]

To the best of my recollection, surfaces of a boat hull are properly constructed using conical surfaces - i.e. surfaces constructed between a single point and an arc (conic or otherwise). Subsequent conical surfaces can be constructed using axis (intersections of planes) for construction of new surface conic end point and intersections between horizontally extruded surfaces and top surfaces (new conical surface base curve). All in all, a fairly complicated process. Each finished surface should be of one color using shaded curvature analysis, and all surfaces should be of one color (usually a light green color showing "0" surface curvature deviation). A "rainbow" shaded curvature analysis indicates an improper surface.

 

[cpoirier]

Truth be told I know nothing of hull design.
mechdes1a, can you upload a model showing the technique your describing?
All of life is a learning experience. Surfacing is something I am interested in.
Also Dave, my model is not a good surface model, Where the Boundary blend ends at the front is done wrong. I was trying to draw a Mako center console hull.

As for hull design......
All I can tell you is my 20' seaswirl has 5.7L 250hp VP, and at 45mph there are only the small flat spot in the water, at 50 she either rides on the outdrive (very scary) or gallops in and out of the water.

Chris

 

[mechdes1a]

cpoirier, sorry but no models available to illustrate my point. Models proprietary to a past employer. I can explain how to make a conical surface. Make two parallel planes. Construct a point on one and a curve on the other. Make a boundary blend surface using that single point and the curve you just sketched and you will have a conical surface. the sides of a conical surface will always be co-planar. On a boat hull, that start point will be way above and to the outside of the hull footprint and to the front of it also so that the resulting surface slopes inward towards the bottom of the hull and back away from the nose of the hull. All other surfaces on a boat hull are constructed similarly based on your first conical surface in the manner which I described earlier - each one inverted to the last for the most part like a saw-tooth (point above on one conical surface and below on the next). Individual conical surfaces are trimmed by longitudinal surfaces to form second-tier boundary curves and the hull goes on to the next level using the same technique of conical surfaces. These longitudinal surfaces are angled to give that "Star" appearance you see when you look at a boat hull from the front.

Sounds like you might need to keep that 20'-er of yours below 45 mph ;-)

 

[cpoirier]

Wife has me keep her <35.
Hi quality surfaces have always been a fascination but never had need at work for them.
Any way you could make a dummy model that has nothing to do with a boat?

Chris

 

[HO-229]

Chris,<?:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><O></O>
Thanks for the feedback, sorry for the late response (away for the holiday).<O></O>
You have the fundamentals of aircraft and ship lofting figured out.<O></O>
Ellipse, Hyperbola, Parabola, and the circle define shapes within the conic family; your model of the boat only lacks theextensive use of the conic. <O></O>
The basic ProE conic is developed utilizing the following: starting point, end point, and a shoulder point. <O></O>
The creators of ProE had the aircraft and ship designers in mind when they integrated the conic and intersect tools amongst several other functions.<O></O>
The basic rule of thumb in regards to aircraft and ship lofting is to develop your shear lines (profile lines) then develop your top view shear lines then develop your long lines to bind the conic start, end, and shoulder points. I hope all this makes sense...
I am no expert at ProE (still sorting out the details) but lofting with conics and splines is well documented and can be easily picked up with a basic understanding of the methodology.<O></O>
The below references define the practice well, don