Ergonomic Knife in AutoCad2012 - Big Problems!

[duggibobo]

Hello everyone! My name is Oliver and I'm on my 2nd year at high-school.

 

I'm in a CAD-course and it's not going to well. We were supposed to make something ergonomic and I decided to try out to make a knife.

 

I've gotten into a few problems.

I started with making the knife in a 2d model, with all the outer lines to make it get a shape

Afterwards I made the lines as high as the knife is supposed to be. I wanted it to be a filled box, but I dont know how

Now the problem is? There is a large hole in the middle of the knife.

It's still only lines, and I have no clue how to make it '' filled ''

 

The assignment was to be delivered 1 week ago and I'm quite panicy. Any1 can bear with me and tell me how to do or can make my knife look good?

 

Here it is: http://www.speedyshare.com/5XdEq/Kniv-fortsattning.dwg

 

What needs to be done:

1. Fill in the handle.

2. Make the edges of the handle soft and nice.

3. Make the '' knife egg '' going towards a knife-looking thing.

4. Put on some kind of color on it

 

Thank you so much! I appreciate all answers, and as you can see, Im not experienced in CAD. Its the first course but our teacher is kindof crazy..

[ReMark]

First. No need to double post. It can cause some confusion down the road as people respond.

 

Second. Are we to assume this was supposed to be done as a 3D model?

 

Update.

 

So I just opened your drawing and answered my question. You do need this as a 3D model. The problem is you extruded individual lines and ended up with surfaces instead. It also appears that you might have drawn this using "constraints" without realizing it.

 

Note: Had you used the PRESSPULL command to give your knife handle the required height you would have ended up with a 3D solid.

[ReMark]

This is the result you were probably looking to achieve right?

 

Note: You should have also used the PRESSPULL command on the knife blade. Hatching it with a solid pattern was not the way to go here.

[ReMark]

Knife blade.

 

Your geometry didn't quite work so I had to tweak it a bit. Seems you had an odd bit extending out beyond the tip of the blade. Anyways, I joined up the lines/splines making up the profile of the blade with the PEDIT command and extruded it 3 units.

[ReMark]

The two parts assembled. No major changes to the geometry were made.

This was really done for demonstration purposes only. You can take it from here now. Good luck.

 

Oops. One last thing. You can round off the edges of the knife handle via the FILLET command. It might take a try or two as the wording for the command (look at the command line) is not very good. You might find yourself asking "What are they asking/telling me to do?".

Edited February 21, 2013 by ReMark
spelling

[SLW210]

I deleted your other thread and moved this one to the AutoCAD 3D Modelling & Rendering forum.

[ReMark]

What needs to be done:

 

1. Fill in the handle. Use the PRESSPULL command on a complete profile of your knife handle.

 

2. Make the edges of the handle soft and nice. One option would be to use the FILLET command to radius the edges. Note: I could only get this to work on three of the four edges. May require going back and reworking the original geometry.

 

3. Make the '' knife egg '' going towards a knife-looking thing. Huh? Sounds like my wife when she's describing the thingy that goes to the whatsit next to the dohickey under the hood of the car. Turns out you meant kinfe "edge".

 

4. Put on some kind of color on it One option would be to put the blade and the handle on two separate layers that each have a different color assigned to it. Then change your visual style to either Conceptual or Realistic.

Edited February 21, 2013 by ReMark

[ReMark]

As I suspected a little reworking of the handle profile allowed me to fillet the edges. I used polylines and arcs instead of splines. That is not to say splines should not be used but I seldom think of using them.

[ReMark]

A close up of the filleted edges.

 

One last thing occurred to me and that is the blade of the knife should be tapered so it appears sharp. I failed to think of that until just now. I'll have to give it some thought.

Edited February 21, 2013 by ReMark
spelling

[duggibobo]

Thank you so much for all this, but what program do you use to create these?

Because can I post them onto AutoCad or how am I supposed to fix it all together into a [Autocad Drawing] file?

 

Thanks a lot!

[ReMark]

Close but not quite right. Note the edge near the tip. Argh!

[duggibobo]

Could you send me the .dwg file if youre working in autocad? And then I'll try to do these things myself! You're amazing for doing all these: The work need to be sent for tommorow so I need to have it in the near future

[ReMark]

I'll demonstrate anything you have a question about.

 

I'll post any needed images that you want.

 

I'll answer your questions.

 

I'll suggest commands I think you should be using.

 

But I will not send you the DWG file. Sorry.

 

Many of us have taken classes and have had homework or projects to do. I would venture to say that given the calibre of the people I know here at CADTutor they never tried passing off another person's drawing as their own and you should not do so either. Half of the learning can be realized in the struggle to succeed. I hope you understand the way I feel and no offense is meant.

[duggibobo]

Ok I understand. Do I have to remove the extruded sides before presspulling? When I use the command Presspull and click in the middle of the handle, it says something like: Nothing could be targeted or something like that

[ReMark]

Give me a moment. I'll be back.

[JD Mather]

I didn't open the file as it wasn't attached here (and I don't go to filesharing sites as I have had them install stuff on my computer).

But

delete the extruded surfaces being careful not to delet the original 2D (you can do this from a side view).

 

Some functions automatically remove the original 2D if you don't have delobj set =0 Do that now.

I prefer to put my 2D profiles on a separate layer than the 3D solids and use different colors for each.

 

Make backup copies (File Save As) each step in case you make a mistake.

[ReMark]

Use the attached drawing for your second attempt. You drew the profiles; I only modified them slightly so they'll work better for you.

 

Note that the blade and the handle have been put on separate layers.

 

I suggest that you work with a copy of each profile and leave the originals alone. Think of it as insurance. If you want you can put them on layer "0" and freeze the layer as an extra measure of caution.

 

KnifeProfiles.dwg

KnifeProfiles.dwg

[duggibobo]

Thank you so much ReMark!! Your profiles are very helpful! So far so good, looks good and Ive put them both together. And I've done fillet on all the sides to make it look cool. However, what I've gotta do now is to fix the knife egg so its actually sharp. How to do this?

 

Once again, thank you so much for helping me. I didnt know this kind people existed in this world.

[ReMark]

You made me laugh. It's referred to as a knife "edge" not a knife "egg".

 

Well as I demonstrated I was about 90% of the way there but did not succeed. I would have to go back and give it some more thought but I cannot do that right this minute. Maybe JD Mather has a workable solution.

 

OK...an idea just came to me but I'll have to test it first. I'll be back.

 

Alright, I think I know what could be done to create the edge. You would basically have to extrude a tapered shape longer than the knife's cutting edge then subtract that from the extruded blade. The profile would look like a block letter "V". Think "helvetica" font.

Edited February 21, 2013 by ReMark

[ReMark]

Sharpened knife edge. Sharp enough to cut an egg!