Need some Routing advice

[wizer]

I have a 8mm sheet of mdf that I need rounding over.... What size bit do I need? I have a 24pc routing bit set from screwfix. There are round over bits in there:

25mm x 6mm
28mm x 8mm
31mm x 10mm
38mm x 12mm

Also on the diagram of the contour it looks like it leaves a 'lip' at the top of the curved edge, can I make it so it just contours all the way round? Like the top of skirting (best way I can describe)

Cheers

 

[Aragorn]

Just pick the size of roundover that you'd like. It's purely aesthetic. The 6,8,10,12mm sizes refers to the radius of the curve. So for 8mm MDF, you would probably use the 6mm. The 8mm will round all the way to the bottom edge, and there will be nothing for the bearing to ride against.

The lip you see on the diagram is just showing an option for creating a roundover with a lip. If you don't want the lip, just set the depth of cut on your router so that only the radius part is protruding beneath the base.

Make a few test cuts on some scrap to fine tune the depth of cut to get the arc of the radius just level with the top of the MDF.

 

[Steve Maskery]

Wizer,
The lip you refer to, if it at the bearing end, your bearing will cut an ovolo, ie a round and a step. You can replace the bearing with a larger one to get just a roundover. Similarly if it comes with a roundover bearing you can replace it with a smaller one to get an ovolo cut.

A step at the top end is, as Aragorn says, just a case of cutting depth.

Cheers
Steve

 

[wizer]

thanks guys. It went great and looks good. Thought routing might be a bit more tricky then that, i'm keen to learn more now.

 

[Gill]

Hi WiZer

Just as there's a slippery slope with handtools, there's a bit of grease on the path down to routing . You'll soon be debating the merits of the Leigh D4, 'rat, Incra fence and so on...

But routers are fun !

Gill