# Oval dome



## Gene Howe (Jul 10, 2007)

Can somebody help me construct a jig to rout an oval dome of 5"X8"?
Center of the dome should be around 3/4" high.
Thanks.


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## CharleyL (Feb 28, 2009)

I would first cut the stock in the oval shape desired. Then I would use a router mounted on a bridge with a mortising bit and some curved templates/tracks for the router bridge to follow. I would design the bridge and curved tracks so the router could make a pass from the top center area down to the edge of the part, then rotate the part slightly, re-clamp and make another pass, repeating this until the work had been routed all the way around. It will likely take some sanding to clean the part up, but it should make the curve that you want. I've used a router bridge before, but never for something quite like this.

It will be interesting to see what others come up with. Harry, how would you do this?

Charley


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## bobj3 (Jan 17, 2006)

Hi Gene

Sounds like a good job for the ShopSmith lathe, Off Center setup..

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Gene Howe said:


> Can somebody help me construct a jig to rout an oval dome of 5"X8"?
> Center of the dome should be around 3/4" high.
> Thanks.


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## Ralph Barker (Dec 15, 2008)

Interesting challenge, Gene. The bridge that Charley mentions sounds like the right approach to me, perhaps using elliptical rails and guides. Both would be specific to the dimensions of a single sized dome (concentric to the dome curve), of course. 

Otherwise, this sounds like an application for a 3-D CNC system.


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## bobj3 (Jan 17, 2006)

Hi Gene


Bob R. of the RWS came up with a great jig to do the legs on the table below, I think it will do what you want also..you may want to check it out.

1307-1308. Round One-Leaf Table (Two parts)

Router Workshop: Series 1300


This versatile accent table features a triangular shaped lower shelf and three unusual shaped legs with a swinging gate leg that supports the one leaf. 
There is a top shelf as well just below the main table surface that does not extend below the leaf. 
This table is designed to go against a wall or in the middle of the room for family or living room comfort. 
In Episodes #1307 and #1308 of the Router Workshop, Bob and Rick shape the *unusual legs* and table features with the router.
1307. Round One-Leaf Table, Part 1
1308. Round One-Leaf Table, Part 2

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## gav (Oct 12, 2009)

I'd start with something like this in mind, but right now I have no idea how I'd work out the curve to get the exact size you want.


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## Gene Howe (Jul 10, 2007)

Thanks a bunch, Gav. That will definitely work.
Now, to figure out my arcs. 
Thanks again.


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## bobj3 (Jan 17, 2006)

Hi gav

That's almost the same as the RWS one that Bob R. came up with but it has a oval flat bar that the router rides on over the hill jig..

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gav said:


> I'd start with something like this in mind, but right now I have no idea how I'd work out the curve to get the exact size you want.


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## gav (Oct 12, 2009)

Does it work Bob ? Mine is just a distilled idea from various dishing jigs I've seen. I've never tried making one let alone using it.
I just found something that requires less material to build and I would have to say is an even better design.


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