First try at Kukri - Positives and Negatives welcome

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Absinthe
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Joined: Thu May 17, 2018 12:20 am

First try at Kukri - Positives and Negatives welcome

Post by Absinthe »

I welcome all comers both positive as well as negative comments on this. I am trying to teach this tool to myself, so without criticism I doubt I will do well. And, if I am doing things the absolutely most difficult way possible, I would appreciate a quick push in the correct direction.

Here is the FCStd file:
[https://www.dropbox.com/s/540fj7bh8c61 ... FCStd?dl=0

Here is the FCStd1 file:
https://www.dropbox.com/s/71rg2r449vnlx ... CStd1?dl=0

Here is the pov:
https://www.dropbox.com/s/g245qx4s9uit2 ... d.pov?dl=0

And here is the rendered image:
image of kukri
image of kukri
2.png (44.63 KiB) Viewed 1942 times
Hopefully I was able to effectively link the files on dropbox.

Thanks for looking!
chrisb
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Re: First try at Kukri - Positives and Negatives welcome

Post by chrisb »

Absinthe wrote: Wed Jul 27, 2022 6:39 pm Here is the FCStd file:
[https://www.dropbox.com/s/540fj7bh8c61 ... FCStd?dl=0
The page doesn't exist.
Here is the FCStd1 file:
It is only a backup file. It is not needed here.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
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Shalmeneser
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Re: First try at Kukri - Positives and Negatives welcome

Post by Shalmeneser »

From FCStd1 (backup page) :
* Do you need to work with 2 workbenches (Part & PartDesign) ?
* No dimensions for the Outline sketch ?
* Blade002 and Handle002 are from Outline ? You should cut the outline to get Blade and Handle.
* Your TechDraw page is empty.
* If you use Part wb, I'd like to see only one top function.
Absinthe
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Re: First try at Kukri - Positives and Negatives welcome

Post by Absinthe »

I used parts design as much as I could. However because I couldn't seem to get chamfers to work the way I wished, I made thin ones then used "mirror" from parts to put them together. I also found it difficult to figure out how to use the subtractive primative, so I did the positional work using a real primative then used it to place the subtractive primative. Probably an easy way to do this in parts designer, but I couldn't figure it out.

Even with mirroring I still had issue laying these things back together.

The bevel on the blade, once I figured how to get the chamfer working was done by eye. That meant when doing the subtractive primative for the ricasso plunge line I had to tweak and poke to get it to line up with the bevel chamfer. I was also never really able to get the fillet working. Or really any other tools for shaping the handles. :(

I am not sure what you mean about the dimensions in the sketch. I kept doing lots of constraints until it would go orange and stop me from working. Ultimately I would remove all the constraints and start over. Of course that would mess up ally spline controls. I finally got to where I had the shape I wanted, and it was closed, I was so happy I just closed it and went forward.

Initially I thought I would make the blank, then modify it, ultimately add handles to it such that you would still see it between handles. "Full tang" is what it is called. Unfortunately, I couldn't effectively modify the pad the way I was trying to Soni changed strategy to where I duplicated the sketch and placed a cut line to come up with the three parts (handle, ricasso, blade). This seemed wrong. But, I had to do something. :)

Basically I am a monkey with a mallet at a keyboard :) I keep poking things and pressing buttons until something happens. I figure if I do something to some sort of completion, I can get reasonable advice about what I have done wrong, and how to do it better. I guess I am looking for a guiding process.

As for the techdraw I was focusing so much on the rendering I wiped out what had been placed there.

I did export to STL and rendered okay from Blender. I got some renderings from pov but was never really happy with them.


Blender render
Blender render
blender_kukri._imp.png (228.05 KiB) Viewed 1628 times
Techdraw page, latest
Techdraw page, latest
g11.png (328.41 KiB) Viewed 1628 times
Attachments
Original tech drawing
Original tech drawing
kukri.png (242.52 KiB) Viewed 1628 times
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Shalmeneser
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Re: First try at Kukri - Positives and Negatives welcome

Post by Shalmeneser »

:idea: (only in PartDesign wb)

You don't really need B-spline here, some arcs would be better.
Attachments
kukri_SHALM.FCStd
(616.26 KiB) Downloaded 36 times
Capture d’écran 2022-07-29 122952.jpg
Capture d’écran 2022-07-29 122952.jpg (41.8 KiB) Viewed 1563 times
Absinthe
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Re: First try at Kukri - Positives and Negatives welcome

Post by Absinthe »

I did another with just arcs using the polyline tool. Funny thing the blade was easier to do as arcs than the handle ;) someone shared a macro to convert a selection to arcs. Sometimes it works. I do, however, like the splines.

I also have another one I was working on that still uses the splines but is a little tighter. Slowly, I am getting it. Still not sure I wouldn't be better off just doing it in Blender.

The one I did today is using only the parts designer and nothing from parts. I also played with subtractive pipe of something but didn't use it in anything. It seems like it will be good for doing a hollow grind.

I did use draft to do some scaling. But it was all otherwise parts designer.

Still don't quite get how to manage and break things up. I think materials will help. Seems once things are together it is hard to have more than one material in volved. When I sent it to blender it was all meshes so that made it a bit more straight forward.

It does seem that it will make sense for parts/bodies all be made of the same material. Which will make using materials more possible. But I haven't even looked into assembly yet.
Absinthe
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Re: First try at Kukri - Positives and Negatives welcome

Post by Absinthe »

Also found out that .19 and .20 are different enough to cause some grief.
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Shalmeneser
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Re: First try at Kukri - Positives and Negatives welcome

Post by Shalmeneser »

A body is one continuous piece of material.
Should look for other knifes in the forum, it may give you ideas.

B-spline are hard to reuse in FC. Arcs are more your friend.
Absinthe
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Re: First try at Kukri - Positives and Negatives welcome

Post by Absinthe »

I have been using them in Inkscape. Quite useful especially for things that were probably originally done with a French Curve. I do recognize the benefit of arcs though, I have lots of specific sized wheels to use with my belt sander. So it would be to my benefit to use a few specific arc sizes in my designs. Since I am presently looking towards classic folders they may be worth looking into much closer. The polyline tool is pretty fun, for what that's worth.

I would like to perhaps animate the opening and closing of one at some point.

As for the body I was having issues doing chamfers without something to break it up. When I was doing more blender there was a way to split something up with parallel slices. Made quick work of a table from a solid block. I found a similar tool, but wasn't sure it was doing things the same.

Lots of crashes today. :( Most recovered well fortunately.

Pretty sure the lofts and pipes are going to be useful. Lots to learn.

I am not really sure why all the constraints are necessary on the sketcher. Also, can I do 2D in something else like Inkscape or libreCAD and bring it in as a sketch to extrude?
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