Weekend Project #1 Simple Folding Knife Handles with Carbide Create

Is anyone interested in participating in a weekend project series?
I think it would be fun opportunity to skill share by posting a project file or challenge and we can learn together as we go along.

As a test, I will be starting with a Knife Handle Project using Carbide Create.

If anyone wants to document and share a process using a different CAD program (Onshape, Fusion 360, Rhino, etc.) that would be awesome!

My base for this project will be a Folding knife kit from Amazon (and Ive seen it carried at Rockler as well)
If you have a knife you want to replace the handles on, this would be a great time.

For this project I will only use Carbide Create with an inlay of some sort.

Any one that would like to buy the kit or use another knife should be able to follow along and adapt the same techniques.

As for handle material, I will try a couple different materials, now that we have over 30 materials to choose from :sunglasses:

I will update this post when my kit arrives and I un-box the contents.

My kit arrives tomorrow,
Whos in?

Heres the link to a past knife handle project using Rhino and meshcam for a full 3D contour:

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I would be interested. Probably not every weekend…

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I’m definitely in for weekend projects! Knife making isn’t that interesting to me presently, though, so I’ll catch the next one. I made your X-Mas ornament last year, and that was great fun.

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@ApolloCrowe I’m definitely interested in this exact type thing. I’m hoping to design a custom bamboo handle for my CRKT Shizuka Noh Ken in Fusion360 and document the process. I ordered 3 sets of cutters from the Carbide store which I hope to receive in time to machine it. GAME ON!!!:wink:
<img src="/uploads/default/original/2X/4/47ce6419938e72b19fc5510ae34736afb0c21e9a.jpg" width=“320” height="70!>

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I would be interested but not till this damn heat breaks

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@Jerrylee
This is great, your details will be different, but the process will be very similar.

@Bonch
Grab a lemonade and enjoy the show.

I would like to give it a try. I already have the knife kit, it has been on my “Project Shelf” for a while

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@ApolloCrowe I’m in. I’ve been working in Fusion 360, so I’ll do mine that way. I just saw this, so just ordered the kit.

I’ll probably do mine with G10 handles. What are you going to use? I’d like to follow your lead!

@rderstadt G10 - nice choice.
The material will be what I have on hand- I know I have some hardwood and plan to use some brass for an inlay as well.
I will start with some tests in acrylic to prove the design first.
My kit arrives tomorrow!

Parts are in-
The Sarge Folding Knife kit contents:


The kit was missing a little screw…
Rockler has some nice instructions for the kit:




Heres some 1/8" thick stock, this would be the thinnest that would work with the stock belt clip.

Ok, next step is tracing the knife handle in Carbide Create, or your CAD of choice.

Almost ready to get the Knife “Scale” project into Carbide Create, First I need a clean tracing of the Handle and something for Scale.
A Penny happens to be .75" in diameter so Im going to use that dimension in Carbide Create to scale my background image map to.


Any body know why they are called scales?

I folded some paper over to make a matched pair to trace in CC.
I prefer a mechanical pencil for tracing, this (Rotring tiki is pretty neat.)

I was able to extend the lead and get all the way through the knife to mark the Hole locations.

I also could have used a transfer punch, 2mm was closest. Dont forget to transfer the hole locations through the paper to the other half.

Scissor magic and heres the picture that will be used as the background image in Carbide Create and traced.

Next is scaling the image in Carbide Create and tracing the outline.

Hows everyone doing?
Happy Friday!

Tracing the knife scale pattern in Carbide Create

To place the knife scale image click the Document Background on the Job Setup pane in Carbide Create.
This is where Grid Spacing can be adjusted, as well as placing, scaling, and adjusting a background image for tracing.

I drew a circle with a .375" Radius to match to the .75" diameter Penny in my background image and scale the image until it matched. I also measured the scale mounting holes in the knife at 1.9" center to center, and double checked my scale with a 1.9" tall rectangle.

Next we need to draw a closed curve around the handles.


Couple tips here:
1-To get your curve to be closed- zoom in and make sure to end the line on the same grid intersection that you started on.
2- I found using as few control points as possible will create the smoothest tracing when doing the final adjusting of the Nodes with handles.

Next Step will be to select a tool and material to cut a first test for fit.
I will be using a 1/16th square endmill and 1/8th acrylic.

There’s a bit of information on Bezier curves on the wiki

http://www.shapeoko.com/wiki/index.php/CAD

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Heres the First test in Blue acrylic, the fit was really close, close enough to prove the penny for scale method, but using graph paper and perspective correction would be a more correct approach to this tracing step of the process.

Using clear acrylic for the first test made it easier to see what areas of the design needed to be modified.

The Outline curve was close to the perimeter of the knife, but it needed to be fixed.

  1. I copied the existing outline and corrected it based on the measuring first sample cut.

  2. To re-assign the toolpath to the corrected curve; Edit the toolpath and CNTRL unclick the first outline and then CNTRL click on the corrected outline.

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I’ve stuck an object on a scanner with a reference (like a 6" metal ruler) and then pulled that scan into CAD and worked from there. That can work well if the object sits flat.

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@ApolloCrowe - I would like to do two layers for the scales, so there is a thin line of color (from the first layer of G-10). I’ve been debating on the best approach:

Option A) Model each part individually, then sandwich them together.

Option B). Glue them up as if making a traditional handle, then routing one side, then the other…treating it as one large block.

Seems like (B) is riskier, but might yield better results.

What do you think???

@rderstadt

First I would test the design and run a first cut in some scrap with either option.
FYI- You can get 2 sets of scales from a 5" x 4" x .125" sheet of acrylic.

I prefer fasteners over adhesives, but I have a feeling option B) glue up would be best if your doing a 3d contoured design.

Can you post a screen shot of your design?

I have attached the Carbide Create file and a DXF file as well.

Folding knife kit scales 405.c2d (565.7 KB)

folding 405 handles with penny pocket.dxf (586.6 KB)

If anyone is interested in a Knife Project- Rockler is having a Sale on Knife Kits through Sept. 2nd.
They have several designs to chose from, the Large Folding Knife (SK-405KIT) is the model used in this tutorial.

http://www.rockler.com/rockler-promotions/current-promotions/sarge-knife-hardware

Curious if anyone has tried this and used fasteners to hold the scales down. If not, what did you use to successfully secure them? I am working on a similar project and am having issues with getting the right type of hold-down.