# Round-nose bits, that aren't "round"???



## tobnpr (Feb 5, 2013)

Is there such an animal?
All round-nose bits that I see are true half-round...

I'm using a duplicator for gunstock replication. Large surface areas, often not very pronounced radii, but by no means "flat".

The RN bits just don't seem to be well suited for this purpose because of the extremely small amount of contact area. It's like whittling a gunstock with a rotating pencil point.

I'd end up with a much more finished product with less hand sanding, if there were a "dish" shaped bit, where it was not a true half-circle, but rather a radius section of a much larger circle- allowing more surface contact and cutting area- while still being able to conform to the surface without "flat spotting".

Just wishful thinking?


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## Mike (Nov 22, 2004)

Mike, perhaps a bowl cutting bit would work for you? You can view several sizes here: Carbide Router Bits | Router Bit Sets | Shaper Cutters | Saw Blades | Planer Knives | Jointer Knives | Infinity Cutting Tools


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## tobnpr (Feb 5, 2013)

Thanks, interesting idea, but it looks like they are flat at the tip...which seems to defeat the purpose as only the flat area would make contact with the surface. Something 3/4"-1" wide, with a very shallow continuous radius is what would fit the bill...I think...

But this is all new to me.


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## bobj3 (Jan 17, 2006)

see the set below...( 43.oo for the set below from elite)

http://www.elitetools.ca/en/

http://www.ebay.com/itm/1pc-1-2-SH-...807886480?pt=Routers_Bits&hash=item1e74c1f290
--



tobnpr said:


> Is there such an animal?
> All round-nose bits that I see are true half-round...
> 
> I'm using a duplicator for gunstock replication. Large surface areas, often not very pronounced radii, but by no means "flat".
> ...


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## Phil P (Jul 25, 2010)

tobnpr said:


> If there were a "dish" shaped bit, where it was not a true half-circle, but rather a radius section of a much larger circle- allowing more surface contact and cutting area- while still being able to conform to the surface without "flat spotting".


Hi Mike

You might want to look for something like a dished panel mould cutter such as this style.










Sorry that's a UK supplier (Wealden Tool), but I know of only a few supplirs of this type of cutter in the USA other than Amana who sell a Horizontal Crown Moulding Bit which is similar. At least this typreof cutter gives you a flatter curve to work with

Regards

Phil


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## befirst (Apr 19, 2011)

try a milling machine radious endmill thay have a true radious and thay make baul mills also try habor freight northstar or google endmills
have fun (life is great 0


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## Willway (Aug 16, 2012)

*Core Box Bit?*



tobnpr said:


> Is there such an animal?
> All round-nose bits that I see are true half-round...
> 
> I'm using a duplicator for gunstock replication. Large surface areas, often not very pronounced radii, but by no means "flat".
> ...


Don't give up Mike, what you may be looking, if I understand correctly, may be a 'core box box' bit. Whiteside Tool Company has diameters up to 2 inches. On the Whiteside site scroll down to 'form tools' then select 'round nose(core box)'. *These do not cut a flat bottom.*

Amazon.com: core box router bit

Whiteside Machine Company


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## TWheels (May 26, 2006)

tobnpr said:


> Is there such an animal?
> All round-nose bits that I see are true half-round...
> 
> I'm using a duplicator for gunstock replication. Large surface areas, often not very pronounced radii, but by no means "flat".
> ...


First I should have welcomed you to the Router Forums

I do not understand what you are trying to do. Do you mean round-over bit instead of round-nose bit? It might be helpful for you to welcome enough newcomers so you can reach the 10 post threshold so you can post a picture or drawing.

In line with Phil, another possible source is MLCS who have a variety of sizes of cove crown molding bits, and other architectural bits that might serve your needs.


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## jschaben (Jun 21, 2009)

How about this one?
1 PC 1 2" SH Horizontal Crown Molding Round Router Bit | eBay)


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## IRONMULE31014 (Feb 16, 2013)

What to do ,what to do Well anyway welcome Mike


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## tobnpr (Feb 5, 2013)

To all:
THANKS! Sorry I hadn't had the opportunity to check back, I do appreciate the time and thought for the responses.

Phil and John...
I think you may be onto something with the crown molding cutters.

I know it's hard to visualize, and far as I know, duplicators are a unique use for routers that's typically outside their "usual" applications .

For many, many years- duplicators were THE method of duplicating and manufacturing gunstocks- even on very large commercial scales.
I've seen Terrco duplicators that would do twenty at a time- the machines are dinosaurs now, all replaced by CNC machines.

The CNC can cut these perfect radii because of their precision....if I were capable of advancing a 1/2" round nose bit a few hundredths of an inch at a time, whittling it down with that pronounced a radius would work. Problem is that I can't- so I end up with "skips" or high spots, and the only way to get rid of them, is to sand them out.

Not too much information online on technique, and I suspect a lot of guys keep it pretty close to the vest if they're into it for commercial purposes as I am.

I do think the crown cutters will work! The search is on...

I love this place....:yes2:


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