Modeling a.... banana. !NSFW!

[epheterson]

So this isn't my first rodeo in SolidWorks, but I've found myself a little stumped when modeling a banana.

 

It's the inside of a banana, so not the geometric peel. It begins a cylinder then I'd like to model the tip something akin to this picture:

 

I'm thinking I need either a curve, or multiple planes offset from each other at different angles. I'd put multiple cross-sections on these planes, or along the curve. I'm not sure how to create planes like this, and not a simple way to get the curve in.

 

You think this would be easy, any suggestions?

[ReMark]

Looks like something that could be accomplished with the Loft command in AutoCAD. Not sure how one goes about doing it in Inventor. I wonder how many people have taken the time to model fruit or vegetables using Inventor?

[Jack_O'neill]

I only had a few minutes to play with it, so I didn't do the part with the peel. Never tried to draw a banana before. Got more work to do on it, but the basic shape is almost there. Got somewhere to be most of today, but when I get back I'll play with it some more. Don't quite have the ribs the right shape yet, but it was good enough to try the concept. Did this in Autocad. Drew the bumpy shape, then a curved path. Copied the bumpy shape along that path in a few places. Towards the small end, I scaled the bumpy shape down a couple times, then lofted along the path.

 

Like I said, I'll make it look better when I have more time. Best I could do in the 10 minutes I had to play with it.

[Jack_O'neill]

Well, that was a little off, don't know what happened there. Gotta go, fix it later.

[ReMark]

  Jack_O said:

Well' date=' that was a little off, don't know what happened there. Gotta go, fix it later.[/quote']

Got to take it slower when playing with your banana Jack.

[shift1313]

  epheterson said:

So this isn't my first rodeo in SolidWorks, but I've found myself a little stumped when modeling a banana.

 

It's the inside of a banana, so not the geometric peel. It begins a cylinder then I'd like to model the tip something akin to this picture:

 

I'm thinking I need either a curve, or multiple planes offset from each other at different angles. I'd put multiple cross-sections on these planes, or along the curve. I'm not sure how to create planes like this, and not a simple way to get the curve in.

 

You think this would be easy, any suggestions?

 

 

One thing most people dont realize is you can loft to a point. For most of the texture I would use an image but you can get the base shape with a point, centerline path, and a single profile. Ill try to draw something in a little bit.

[epheterson]

I did not know you could loft to a point! Thanks for the comments so far I did realize that lofting is the best technique, but suppose I don't know how to make a nice curve for it. Jack, yours looks great but if it can look right, I think it should stay a cylinder all the way through. I appreciate your description on how to make it.

 

Again, SolidWorks is my weapon of choice and I'm more interested in how to make it myself than getting a cad file from y'all

 

Thanks for the help

[epheterson]

Update! Apparently we're not modeling the curve but the opposite end, which is the bottom of the picture I posted. This looks like it got a whole lot easier. I think I'm not even going to make rotated planes and just several planes offset with circular profiles on each shifted laterally.

[shift1313]

Well the relations didnt work out as nicely as I had hoped but I did loft to a point and then trim the end back slightly. I wasnt sure what version solidworks you are running so i uploaded an iges file.

banana.zipFetching info...

[Jack_O'neill]

  ReMark said:

Got to take it slower when playing with your banana Jack.

 

:lol::lol:

 

Gonna leave that one alone....gonna leave it alone....

[Jack_O'neill]

hey shift...how about something us poor autocad users can see?

[shift1313]

  Quote

hey shift...how about something us poor autocad users can see?

 

 

Autocad users in a Solidworks forum, thats odd . I didnt save the part file but ill open up that iges or give it another shot in the morning and show you:) it basically looks like a banana

[Jack_O'neill]

  shift1313 said:

Autocad users in a Solidworks forum, thats odd . I didnt save the part file but ill open up that iges or give it another shot in the morning and show you:) it basically looks like a banana

 

Yeah, we sneak in here from time to time just to see what's going on.

 

Don't go to any trouble on it, was just curious what you'd come up with.

[Jack_O'neill]

ok, round two with the banana (yes, it's autocad, and no, it's still not finished).

 

I haven't used it since '93, but I caught myself thinking "man, this would be so much easier in Mechanical Desktop".

[epheterson]

Y'all are awesome!

 

Jack, I attached shift's model and don't know if you caught the memo but I was doing just the banana, not the peel!

 

I figured a way to do it by importing an image, creating planes parallel to Front every 20mm, creating a circle sketch to fit on the image and drawing a top & bottom spline to touch each circle I created. Almost a perfect method for any image I can find! Then I can tweak once I have something.

 

:D:D

[shift1313]

Jack, here is a screen shot of the part i drew. The main body was a loft between two profiles with a center line path. The profiles were the same only a different scale. There was an inscribed circle of 1.5" and 1.25" for each profile. The end was done with a boundary operation but a loft would have worked as well. I drew the same profile on the end with a 0.5" inscribed circle and used tangency between the first them. Plane 1 was created based off a spline i drew for the path so i had a plan normal to my path for the second profile.

 

ps, i know its a banana but i feel really wrong about drawing this and posting the picture online

[epheterson]

Shift, I know what you mean... you should hear my roommate's comments.

 

Anywho I see how you constructed that but how do you get three planes on one continuous curve? You drew a spline from vertical to 1st, and say you did a boundary condition on 3rd, but 3rd looks angled further.

[SLW210]

I really do not want to know what you are doing?

[shift1313]

  epheterson said:

Shift, I know what you mean... you should hear my roommate's comments.

 

Anywho I see how you constructed that but how do you get three planes on one continuous curve? You drew a spline from vertical to 1st, and say you did a boundary condition on 3rd, but 3rd looks angled further.

 

I only have 2 planes in there. I drew a sketch on the Top Plane for my first profile. On the Right plane i drew my spline path. I then created a new plane by selecting the spline and its end point. This will make a plane that is normal to the curve at the end. The last plane was an offset of this plane just to draw the end profile.

[Jack_O'neill]

:lol: This could degenerate really quickly.

 

I saw the bit about not needing the peels, but by that time it had become a challenge. My peels look more like shoespoons but it will get there eventually. It's become one of those things I just want to figure out how to do. Besides, the peel helps make it not look so....what's the word I'm looking for.....uh....

 

--sidenote-- my wife came in the room while I was working on the peeled portion. I didn't notice her standing there at first but when I finally stopped and looked at her she said "You've finally cracked, haven't you? $4000 so you can sit in the dark and draw.....that?" Still not sure that she believes it was a banana.