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George Bokros
07-19-2017, 4:23 PM
Would you do it freehand using just a bearing bit or on the router table with a starting pin and an edge guided bit? Which would be more goof proof?

I have done a test piece in the router table with the starting pin and bearing guided bit but wonder how others would attack this process.

Thanks

Mike Henderson
07-19-2017, 5:41 PM
I use the Microfence circle jig. I decide where the center will be on the table and mark it with long perpendicular lines. Then I take a piece of fairly thin wood (about 3/8") and mark the center with perpendicular lines and drill a hole the size of the pivot point. I then glue that piece of wood in the center of the table with cardboard between it and the table. Use the perpendicular lines to align things.

Then, put the jig pivot in the hole and do a cut with a straight bit to make sure the table is round. Then put your profile bit in the router and route the profile.

Mike

Jim Morgan
07-19-2017, 7:17 PM
Depends on the size of the table.

glenn bradley
07-19-2017, 7:28 PM
As stated, depends on the size as to my approach. Circles and ovals mean routing uphill at a couple of locations at least. Hand held or at the table I like some sort of an edge guide or fence to keep the cut from getting away from me while I climb cut those areas. I prefer the table but, if a top is 36" in diameter and 1-1/2" thick oak . . . I start to question my ability to reliably feed the stock. Whenever I am questioning anything I am about to do in the shop I back off and consider a friendlier way ;-)

jack duren
07-19-2017, 8:09 PM
Router and bearing unless it's a profile I need to manipulate and the bearing isn't an option...
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George Bokros
07-19-2017, 8:17 PM
It is only an 18" round top.

George Bokros
07-19-2017, 10:07 PM
I would use a bearing bit and a starting pin. I need to watch router speed and feed speed since it is cherry.

Yonak Hawkins
07-19-2017, 10:08 PM
18", I'd do it on the router table with a bearing bit. Take it in two steps. Take it slowly but not so slowly it burns and don't stall. If you have to stall or if it's an easily burning wood like cherry, do it in bites.

Jim Morgan
07-19-2017, 11:39 PM
18", I'd do it on the router table with a bearing bit. Take it in two steps. Take it slowly but not so slowly it burns and don't stall. If you have to stall or if it's an easily burning wood like cherry, do it in bites.

At 18", that's the way to go. You can swap the bearing on the bit for a slightly larger bearing (from another bit or a router bearing set). Switch back to the original bearing for a final last pass. Keep your material moving - cherry scorches really easily.

Rod Sheridan
07-20-2017, 8:27 AM
I would do it on the shaper, with a circle cutting jig.

So in your case, router table with index pin so you don't need a bearing and the top is perfectly round...............Rod.

George Bokros
07-20-2017, 8:50 AM
I would do it on the shaper, with a circle cutting jig.

So in your case, router table with index pin so you don't need a bearing and the top is perfectly round...............Rod.

Why would you not need a bearing bit with an index pin? I cannot see how you could do it without a bearing on the bit.

Robert Engel
07-20-2017, 8:58 AM
Why so complicated? Am I missing something?

I would use a hand held router probably with an oversize base.

This is a pretty straight forward process other than dealing with end grain tear out in which case do a climb cut.

Prashun Patel
07-20-2017, 9:00 AM
I would do it with a fixed base hand held router. The reason is that you will have to climb cut away from the long grain/short grain transition at 2 points. If you do not, you will risk tearout with all but the spendiest of bits.

For me, it is harder to climb cut on a router table than hand held. Also, a handheld router will keep the profile more consistent if your top is less than 100% flat.

Cary Falk
07-20-2017, 11:50 AM
I would use a hand held router with a bearing bit also. The Freud quadra- cut bits work great on end grain.

glenn bradley
07-20-2017, 12:22 PM
Now that we know it is only an 18" disc, either method would work and it becomes a personal preference. I have a reasonable collection of bearings. For cherry or other burn-prone woods I would put one on that gets me to within 1/32" or thereabouts, do my climb and regular cutting, swap bearings and take the last 1/32" off in a smooth continuous run. Always more than one way to skin the cat. Did this 20" one with a quickly made circle jig.

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Rod Sheridan
07-20-2017, 12:56 PM
Why would you not need a bearing bit with an index pin? I cannot see how you could do it without a bearing on the bit.

Hi George, the pin holds it a fixed distance from the cutter so the bit cuts a perfect circle, no wiggles, nothing.

A bearing follows all the imperfections, especially a router bearing that's very small, on a shaper the bearing would be 5 inches in diameter or more so it smooths out irregularities a little bit.

The index pin however generates a perfect circle................Regards, Rod.

johnny means
07-20-2017, 4:23 PM
Typically, routing on a table is much less forgiving of imperfections in flatness.

johnny means
07-20-2017, 4:26 PM
I think he might be refering to a pin used to ease entry into the cut.

Charles Lent
07-20-2017, 6:04 PM
If you are trying to but a half round on the edge with a standard bearing end type 1/4 round roundover bit and then flip the table top over to round from the other side to get a half round on the edge of the table, you are going to have problems when rounding from the second side because the bearing will want to ride on wood that is no longer there, because you cut it away during the first pass. A special curved fence can be made from the scraps that you cut the round from by attaching these to your straight fence and then adjusting the fence position so that the bit cuts the 1/4 round on the second side without riding on the bearing. This will result in a full half round of the edge of the piece using 2 passes, one from the top and one from the bottom. If you think you can do it with a 1/4 round bit with a bearing, try it on scrap before doing the good piece and you will see what I mean. The bearing needs to be above the center of the 1/2 round and after the first cut there will be no wood in the right position for the bearing to ride on to properly position the bit to cut the same 1/4 round from the back side. It will cut deeper on the second side pass and leave a step in the middle of the rounded edge.

A non bearing 1/2 round bit (bull nose bit) of the right size, together with the same curved fence jig made from the curved off cuts will do it in just one pass, so long as the center of the bit just touches the center of the edge of the work and doesn't remove any material at that point. The rest of the bit will take care of the rounding both top and bottom in the one pass. They also make a bull nose type bit with a center bearing, but this bit leaves a flat in the middle of two quarter rounds and it will be a flat slightly wider than the thickness of the bearing.

A Starting Pin is just that...for starting a cut. It allows you to pivot the work around the pin to gradually cut into the work with the bit, to avoid dangerous grabbing of the work by the bit.

Make the half round fence jig from two corners of your scrap from making the round. It will let you guide the round edge into the bit and then rotate it to cut the shape of the bit in the edge of the work, without ripping the piece from your hands. The starting pin also works this way, but it is for beginning the cut on irregular shapes. A round fence works much better when edging round work of the same curve.

Charley

George Bokros
07-20-2017, 6:09 PM
I am putting a cove and bead on the top edge of the table top. And yes, I am referring to exactly what Charles Lent is revering to as a starting pin.

I am concerned about the chip out and the burning of the cherry.

Jim Morgan
07-20-2017, 9:57 PM
I am putting a cove and bead on the top edge of the table top. And yes, I am referring to exactly what Charles Lent is revering to as a starting pin.

I am concerned about the chip out and the burning of the cherry.

I believe that Rod was talking about using a centering pin as in a circle cutting jig, but if you are molding the top edge that probably won't work (unless you use a plug to cover up the hole for the pin). Taking an initial cut with an oversize bearing, whether with a handheld router or a router table with a starting pin, and then following up with a light finish cut should be your best bet.

Rich Engelhardt
07-22-2017, 6:02 AM
I then glue that piece of wood in the center of the table with cardboard between it and the table.That right there...
I'd make sure I used something substantial though for the trammel - 3/8" might be ok..
I tried to get by using 1/4" hardboard & it caused me to break 2 straight bits. (1/4").

One little tip about the glue for that cardboard buffer.
If you use Elmer's School Glue, you can wash it all off after you're done routing and you separate the pieces.
I normally use newspaper for that kind of - - what would you call it? buffer? - but I guess cardboard would work also.

George Bokros
07-22-2017, 8:01 AM
I normally use newspaper for that kind of - - what would you call it? buffer? - but I guess cardboard would work also.

In high school we used the brown paper towels as the buffer when we did face plate turning on the lathe. This was a few years ago (I am couple decades past high school now) and the carpet tape had not been invented yet and there were no jaw chucks either.

George Bokros
07-22-2017, 8:02 AM
I used my Dewalt 618 router with a new bearing guided Whiteside bit and accomplished it with no burning and now oops.

On to finishing now.