how to route a groove?

[flat n smooth]

i want to route a groove across a cupped board using an electric router any suggestions on how to?
Thanks.

 

[Mar_mite]

How cupped is it? Is it worth it? If it's not to bad, you could clamp it flat first. But I don't see why you would bother.

 

[Steve Maskery]

Well first I'd plane it flat 'n' smooth.....

Seriously, it's much easier to work on flat stock. However, if you don't want to lose any more thickness, use a router and a jig. I think Charley has done a video of one such jig on here look in the Video section.

There are many examples of similar jigs on the net, as well as on my DVDs.

They are accurate, as safe as you are going to get, and not difficult to make up.

 

[marcros]

Or just clamp a straight edge across rather than having to make a jig for a one off job.

 

[flat n smooth]

ok thanks for all the replies
I was aiming to make a serving board out of a slightly cupped board. I had planned the bottom flat so it sat stable on the table but wanted the cupped effect on the topside with a groove routed around the inner edge of the top

unfortunately Steve the flat and smooth is a nod to my day job as a plasterer not to my workings with wood so far lol

Anyway tried to clamp the board flat and it snapped so I know for next time that method was unsuccessful
thanks all

 

[blackrodd]

When a board is cupped as you have described, cut it on the saw bench in the middle of the "cupping", square up the edges and join back together with a decent glue.
Most of the time this will stay flat.
Don't put it in the dishwasher!
Regards Rodders

 

[ayuce]

I think i would try smtg like that below with a trim router ( lighter and easier to control) Two vedge shaped wood between cupped board and support should be usefull for fixing the workpiece.