# Cutting Small Oval



## lmelton (Dec 27, 2012)

I want to inlay a 1 inch medallion into a knife handle that is 5" x 1.5" x 3/8". I am looking for a solution to make a jig/template that will allow me to consistently and accurately carve out the hole with my router. The thickness of the medallion is 2 mm, and I want it to set flush with the surface of the handle.

As I will produce handle for different knives and kitchen cutlery, the jig/template should be adjustable so I can position the medallion between the brass fasteners.

All I've seen so far that allows me to cut a hole this small, is a CNC unit, which is beyond my means at this time. 

I Photoshopped an image to show an example of what I am trying to do. The white square around the medallion is just an artifact of Photoshop and will not appear on the handle.


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## Stick486 (Jan 4, 2013)

Larrylmelton said:


> I want to inlay a 1 inch medallion into a knife handle that is 5" x 1.5" x 3/8". I am looking for a solution to make a jig/template that will allow me to consistently and accurately carve out the hole with my router. The thickness of the medallion is 2 mm, and I want it to set flush with the surface of the handle.
> 
> As I will produce handle for different knives and kitchen cutlery, the jig/template should be adjustable so I can position the medallion between the brass fasteners.
> 
> ...


 the handles on the knives are never flat, are they???

I'd look to an engraver's machine.. skip the exotic and go manual or semi-manual... 
look into the old style pantograph type machines and you'll see where to go from there
I'd be more concerned w/ developing a vacuum-clamp to hold the cutlery...


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## lmelton (Dec 27, 2012)

Thanks for your suggestions.

You are correct in that knife handles generally have some curve to them, however, I could carve out the oval when it was still a raw scale, which is a flat rectangle. Also, the problem of securing the scale did come to mind, and your suggestion of a vacuum-clamp merits research.

I'm not sure what you mean by "old style pantograph", however, I did find this online. Since it can reproduce letters, I suspect it could carve a shallow oval.


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## Quillman (Aug 16, 2010)

You're gonna have a time routing a pocket for that medallion (for cops?).
Would be thinking about gettiing that same shape onto a disc. That is, making a disk big enough so your oval fits on it. Then drilling. Drilling is 1/10th the problem you're facing with routing, but still a problem.


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## Stick486 (Jan 4, 2013)

Larrylmelton said:


> Thanks for your suggestions.
> 
> You are correct in that knife handles generally have some curve to them, however, I could carve out the oval when it was still a raw scale, which is a flat rectangle. Also, the problem of securing the scale did come to mind, and your suggestion of a vacuum-clamp merits research.
> 
> I'm not sure what you mean by "old style pantograph", however, I did find this online. Since it can reproduce letters, I suspect it could carve a shallow oval.


that's the idea on the pantograph but with a Dremel tool sized router...
perfect the oval template and you should be good to go...
hunt around and you just may be able to find and old manual engraver's model ready to go...


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## Stick486 (Jan 4, 2013)

Larrylmelton said:


> I'm not sure what you mean by "old style pantograph", however, I did find this online. Since it can reproduce letters, I suspect it could carve a shallow oval.


something like these.... 
Googled manual engraving machines... you could look for used...

Manual Engraving Machine
Scott Machine Manual Engravers
Small Engraving Machine | Small Engravers | Vision Engraving & Routing Systems


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## lmelton (Dec 27, 2012)

Aye, aye, aye!

I knew this wasn't going to be a simple solution. My initial plan was to create box with side boards as "chocks" to hold the handle still, and then to somehow secure a template on top and use my router (or Dremel) to carve out the cavity. I would make the template out of 3/4" plywood so it would be deep enough for the bearing on a pattern bit to follow the oval.

Now in theory, all of this sounds simple, until you begin to think about how to secure each component so that nothing moves but the router bit, and it is repeatable from one handle to the next.

So, it seems I'm back to square one. I know this is possible, because I've seen similar projects from some of the big knife makers. The problem is that the ones I've contacted us a CNC machine, which is way too expensive for this small (and non-profit) project.


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## Cherryville Chuck (Sep 28, 2010)

Because the medallion is an odd shape I don't see any alternative to routing it. Stick's method seems to solve all the issues. Your method of work holding is good. I would attach stops on all 4 sides of the scale to a piece of ply wood that you clamp where you need it. You can even shim under the plywood if you need to angle the scale to get the medallion to fit better.

Is there any chance you could get the medallion made round? Quillman's idea will save you time, money, and aggravation if you could just drill it into the scale.


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## Stick486 (Jan 4, 2013)

Cherryville Chuck said:


> Is there any chance you could get the medallion made round? Quillman's idea will save you time, money, and aggravation if you could just drill it into the scale.


Have Forstner Bit Will Travel!!!


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## Cherryville Chuck (Sep 28, 2010)

My thoughts exactly Stick and I'm sure what Pat had in mind. If you look at the medallion very closely it isn't exactly an oval, at least not mathematically. It is more of a shield shape which means you have to trace it as you suggested.


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## RainMan 2.0 (May 6, 2014)

So why can't a jig be built to hold the knife in a repeatable spot , then build a template that can be suspended over the knife that a routers guide could follow .
Not sure how to accurately make an oval hole in the template yet but I'm sure there's ways , perhaps a circle jig in two separate positions to create separate half cuts creating an oval?


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## Stick486 (Jan 4, 2013)

RainMan1 said:


> So why can't a jig be built to hold the knife in a repeatable spot , then build a template that can be suspended over the knife that a routers guide could follow .
> Not sure how to accurately make an oval hole in the template yet but I'm sure there's ways , perhaps a circle jig in two separate positions to create separate half cuts creating an oval?


take a more gooder look at the shape... and pay no attention to the white field around the shield...
guide bushing I think isn't going to work but like what has been mentioned... set that shield on a complimenting round disk...
use a forstner bit to bore for the disk...

gaining on the MISS/KISS principle all the time...


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## otto g (Aug 2, 2014)

I think that the problem here is that the brass medallion will sit flush to the curved surface of the scale. So unless the medallion is made with a curved surface and a flat bottom, this presents a problem for even a CNC system.

I made a number of picture frames that had an oval plaque, slightly larger than the one you have, inset into the lefthand side piece that was curved. The plaque was flat both top and bottom and lay shallow in the curve of the frame. I filed down the banks on the high sections slightly to give an illusion of continuity. To made the oval I used a simple jig with an overhead pin routing attachment. The one I use is from Lee Valley, but there are others. You can position the jig anywhere on your piece of wood. I made the ovals before finishing the outside of the part of the frame.

I would attach the little jig on the back of the piece with turners tape. With the router bit just sallow of the table I would position the piece and then bring the router bit up to the right height and go to it. It took a bit of trial and error, but it was not too hard.

Otto


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## Bodger96 (Mar 18, 2014)

If the medallion has to have a round (Curved) bottom recess you could still use a saddle jig to hold the scale and as long as the top of the saddle jig matched your curve
you would end up with a curved bottom in the recess. Using a small router like a Dremel or a palm router with a template guide should do the trick. I have had to do this type of thing in the past. The engraving machine that Stick is talking about will work fantastic but they seem to be quite pricey. They have units that are specific for round surfaces.

Regards Bob


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## rwl7532 (Sep 8, 2011)

The shield looks to be a half circle and a half oval.
My 2¢.


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## gregW (Mar 14, 2007)

maybe something like this "Luthier Inlay Router Duplicator" may work..

https://www.youtube.com/watch?v=TYCubwavxfs


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## MEBCWD (Jan 14, 2012)

You might look into an inlay set like this and make your own templates.
Inlay Sets - Lee Valley Tools
You can find these set at other locations with different pricing and sizes. Search "router inlay set".


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