Roundovers On A Circular Table Top

[TomInNC]

I am refinishing a circular coffee table that we bought several years ago. There is no edge treatment on the table, and to my eye, it always looked a bit unfinished. While I have it stripped down, I would like to add a slight roundover to the top. I have done plenty of roundovers with my plunge router before, but the pieces were always rectangular. Since there isn't a natural point of entry for the router on a circle, I wasn't sure if it I would run into issues using the hand router here. I do have a router table, so if there's a way to safely round over the edges of a large circle on the router table, that would be an option as well.

 

 

[JohnG]

How big of a roundover are you planning to use? Handheld should be fine, just pay attention to the endgrain sections and whether you are going uphill or downhill. 

For a tabletop handheld is likely going to be easier and safer than trying to keep it on the router table.

[TomInNC]

For the roundover, I am just doing 1/8''. Typically I would just practice on some scrap, but I don't have anything round in the scrap pile at the moment, and I don't really feel like gluing a bunch of boards together to make a circle just for a test cut. 

[JohnG]

What kind of wood is it?

[TomInNC]

I didn't make the piece, but I am 90 percent sure it's black walnut.

[Tpt life]

Just careful of grain runout. Circular tables often require a quadrant of very shallow climb cuts to avoid tear out. 

[curlyoak]

You need the correct router bit with a ball bearing guide. From your questions you might be better off to get a little help. Router tables can be dangerous without experience. Look for a youtube.

[Ronn W]

WIth a sharp bit with guide bearing I think that 1/8" round over should not present any problems.  Keep the RPM's up and don't move the router too fast.

[treeslayer]

+1^

[wtnhighlander]

I would suggest using an extended router base, like an inexpensive circle cutting jig uses, to stabilize the router from tipping. 

Just the base from this Rockler jig is a good example. You don't use the centering pin, just angle the base across the table top and anchor it with one hand, the other hand drives the tool.

[TomInNC]

Thanks for the tips. I do have a Milescraft circle cutting jig with a baseplate, so it sounds like that would be worth a try.

[Mark J]

Is the table top solid walnut, or veneer?

[gee-dub]

Assuming you've checked that it is solid material (rounding over a veneered substrate would be a rude awakening) I would start routing where the grain is running in the same direction.  My routine on round objects or sections of reversing grain on straight runs is as follows:

- Start and route through a section of grain running in the same direction (downhill as some say).

- Stop before you reach the reversing grain point.

- Skip ahead and route through the other section of downhill grain.

- Climb cut from an already routed profile area back through the revering grain areas to connect the whole.

Walnut is not so burn prone as some other materials.  Burn prone or not if you want to take an extra step to assure a smooth final pass use tape.  Run an even strip of tape around the outer edge of the material.  Perform your routing operation as described above with the bearing riding on the tape.  Remove the tape.  Make a final smooth continuous pass with the router to remove the small amount of material let due to the tape being present.

Hope this made sense; I'm on my first cup of coffee ;-)

[TomInNC]

Yes, the table is solid walnut. I've been working on flattening it with handplanes, so I know that much for sure.

 

Gee dub, are you talking about how you would approach this with a router table or by freehand routing?

[gee-dub]

On 5/14/2022 at 8:38 AM, TomInNC said:

Yes, the table is solid walnut. I've been working on flattening it with handplanes, so I know that much for sure.

 

Gee dub, are you talking about how you would approach this with a router table or by freehand routing?

Sorry, free hand.  An 1/8" roundover is not a lot of material but can still cause issues when routing uphill.  I don't have any trouble with evenly figured walnut but the act of following the curve makes even straight-grained material have a reversing point.  You could also knock the sharps edge of with a sanding block before routing.  I have done this with good success on end grain.  Generally on end grain you can clamp on a sacrificial block so the end fibers are supported.  Not so on a rounded edge so climb cutting is my answer.  If you are not comfortable with climb cutting you can climb cut a few end grain sections of scrap clamped in the vise to get a feel for the router's desire to pull you along.

[Chestnut]

My gut was to suggest a climb cut for an 1/8" round over. That's not much material but like gee-dub mentioned it could create chip out issues. Practice climb cutting though it takes some experience to get comfortable with it. Never climb cut with a larger cut than 1/8" though, unless you really know what your doing.

[TomInNC]

Thanks. Will give it a shot this weekend.