Tapered ball nose cutters

[Xxray]

Tr, you seem to be getting a bit obsessed and slightly condescending about this, hows about you buy, use and recommend whatever you want, I'll do the same and we'll leave it at that ?

[ger21]

My point was pretty clear, when a company is using 1/5 of the material and doing 50% less grinding their product is going to cost less, way less.

You are comparing apples to oranges.
1/8" Shank US made bits would also cost 50% less than the 1/4" shank bits.

[rscrawford]

My 'go to' ballnose is a 1/2" straight. The only other ballnose I have is a long, tapered 1/16" (from 1/4" to 1/16" with a 2" cutting length). When I use either of these, I do not normally use a roughing tool path and so I am often cutting 1.5" depth of cut (furniture building, not the normal 2.5D relief work). The long tapered bits work very well for these deep cuts, and I've never had one break.

[TReischl]

Tr, you seem to be getting a bit obsessed and slightly condescending about this, hows about you buy, use and recommend whatever you want, I'll do the same and we'll leave it at that ?

I have no problem with that Doug. What I took exception to were your statements about "sweat shops", the chinese copying precision grinding machinery, etc.

BTW, I never consider participating in an online discussion being "obsessed" since the same could then be said about your replies.

So we should be good.

[TReischl]

My point was pretty clear, when a company is using 1/5 of the material and doing 50% less grinding their product is going to cost less, way less.

You are comparing apples to oranges.
1/8" Shank US made bits would also cost 50% less than the 1/4" shank bits.

Gerry, I think that was exactly my point. I have not been able to find 1/8 shank US made tapered ball nose cutters. So I really feel no need to spend 5-7 times as much to buy US. Of course, if I am doing deeper cutting then I am going to use 6mm shank tools which are twice the cost. I know Precise Bits does not offer 1/8 shanks nor have I been able to find them anywhere else.

BTW, I dropped you a PM a few days ago with a question about your screen set.

[BradyWatson]

For my work, any tapered tool is considered a 'special' and used only when necessary. 99% of the time I am using a ball end mill with a straight shank - unless sub-1/8", then all shanks are 1/8" and necked down from there - as is the industry standard. A 1/16" ball end mill will have an 1/8" shank and be necked down to 1/16". Premium tooling suppliers offer a wide variety of cutting edge lengths. Once you move beyond what is available to Joe Public and establish a relationship with your local tooling guy, a whole world of possibilities opens up & you discover just how little you know and what other goodies are available to make your work easier.

The 3-flute 1/4" shank tapered 1/8" ball end mills from Onsrud and SGS are very good, made from top quality micrograin carbide and last a very long time. I think last I checked either is somewhere in the $50-65 ea range. An 1/8" ball end mill with 1" LOC is somewhere in the $20 range, so you could get 3 for the price of one tapered bit - with all of these tools being made in the US and made from micrograin carbide.

The 2 & 4 flute non-tapered BEMs are equally long lasting and robust - if you know what you are doing. If you properly rough out, there's no reason you can't use these without fear of breakage at the same kind of speeds you'd run the tapered tools. I've used down to 1/64" BEMs without snapping it off. At that point you can't hear material being routed over the spindle - you have to look to see if it's still intact. Woodgrain becomes like 'cables' in some species @ 10% stepover (0.0015")

I know the tapered tools are popular with guys that cut a lot of 3D clipart because most of those models are fairly shallow and it's possible to eliminate a roughing toolpath in many cases. Another application I see these being used on are plinth blocks - saving that roughing toolpath time puts money in your pocket if you are cranking out a lot of them & you can get away with it.

For some, these are the end all be all for 3D finishing tools. I feel that some are short changing themselves when it comes to finish quality if they never run a roughing toolpath. In many cases, the quality of the 3D finishing toolpath result is much cleaner having run a roughing toolpath than just brute force 3D finishing with a tapered tool. This is especially true on light CNC routers that deflect under load and telegraph that into the cut. Nobody wants to believe that their machine could possibly deflect - but it is something to keep in mind...