# End Mills for Woodworking



## epicfail48 (Mar 27, 2014)

Not sure how many people already know this, but carbide end mills for metalworking work great as router bits, and are usually cheaper. For example, a pack of 5 good quality carbide end mills can be had for around $40:
https://www.amazon.com/gp/product/B07FSGBW7S/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1

Compare that to $20 for a single spiral upcut carbide bit and the economics start to look a lot better. The end result of the cut is the same, and your router isnt going to care about the different. This wont help much for profile bits, like roundovers, but straight bits are easy to find and pretty inexpensive. The 1/4" bits i mentioned are an extremely common size and very easy to find, plus the 1/4" shank bits fit in pretty much any router you can find. Other sizes are just as easy to find, though you might have to do some looking to find some that work with your existing router collets. Still, its a handy trick to know about, save a few bucks and get better quality


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## difalkner (Nov 27, 2011)

I agree. The only thing you really need to watch is that bits like these are four-flute and will easily leave burn marks in wood if you're not careful. Gotta' get the feed/speed rates right and then they work great. And they're excellent as a finishing tool if you've used your two-flute bit for the roughing passes.

Good suggestion!

David


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## epicfail48 (Mar 27, 2014)

The four flute ones actually do a pretty good job, so long as your router is hefty enough to keep the feed rate up. As long as the bit is cutting and not rubbing, the wood won't burn I've found


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## kwoodhands (May 1, 2020)

I do a lot of metal working, probably more than wood working. Two flute endmills HSS are generally used for aluminum. 
Three and four flute endmills are used for brass and ferros metals. Four flute are best for woodworking. I would only use endmills in a collet or a holder. Not made for a drill press or any tool that uses a drill chuck. I have used an end mill in a chuck even though it is not recommended. Only used this way for an occasional, light cut . 
HSS is sharper than carbide. Does a better job whether in wood or metal. Do not use double ended end mills in a router or a chuck. Almost all end mills have shanks the same size as the cutter except for in-between sizes.
1/4" shank endmills are rare. The cutter will be 1/4" , 3/16 shanks are more common but would require the same size collet. I would buy only 1/2" diameter shanks if possible.
mike


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## DrRobert (Apr 27, 2015)

The only time I used one for mortises it burned like heck.


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## FrankC (Aug 24, 2012)

Be aware, end mills have different cutting profiles, on many four flute types the cutter does not go past the centre so cannot be successfully plunged into the work, it has to cut into the work from the edge. Most two flute are made to plunge into the work so can be used to drill a hole or make a stopped dado for example. YMMV.


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## kwoodhands (May 1, 2020)

Router bits are made to run fast. 8000 RPM is considered slow. On the other hand endmills are made to run much slower. 
That is why an endmill may burn used in a router. If your router has speed control run it at the lowest speed. Be aware that the Harbor Freight speed control does not work with slow or soft start routers. A friend bought the HF speed control, about $18.00. Did not work on his PC router. Then he tried it on an older model PC 690 I think is the model #. Worked as advertised on this router. New router had soft start, older router did not. I believe the instructions tell you this.
mike


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## Rhidium (May 11, 2020)

kwoodhands said:


> Router bits are made to run fast. 8000 RPM is considered slow. On the other hand endmills are made to run much slower.
> That is why an endmill may burn used in a router. If your router has speed control run it at the lowest speed. Be aware that the Harbor Freight speed control does not work with slow or soft start routers. A friend bought the HF speed control, about $18.00. Did not work on his PC router. Then he tried it on an older model PC 690 I think is the model #. Worked as advertised on this router. New router had soft start, older router did not. I believe the instructions tell you this.
> mike


That's interesting.. What did the speed control do to the soft start routers that made it not work? It didn't slow it down?


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## epicfail48 (Mar 27, 2014)

kwoodhands said:


> Router bits are made to run fast. 8000 RPM is considered slow. On the other hand endmills are made to run much slower


Endmills are meant to run slower in metal. In wood, they dont care, especially carbide end mills. Older HSS end mills might have a problem, but router bits used to be made out of HSS too, and they worked alright

The carbide in end mills is the same as the carbide in router bits, just a marginally different shape. Carbide end mills can also survive being run, in aluminium, at a cutting speed of 2000fpm, that is to say 2000 inches per minute of the material being cut running across the cutting edge. That cutting speed with a 1/4 diameter cutter comes out to 30,000rpm, and again thats in aluminium. In wood, youll never have to worry about speed


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## TimPa (Jan 27, 2010)

"Not sure how many people already know this, but carbide end mills for metalworking work great"

I agree with this. spiral solid carbide bits (downcut and upcut) have been great for the woodworking industry. been running a cnc for couple of years now, and learned that "end mills" - downcut spirals intended for flat bottom cuts, initially design for the metal milling industry - have found their way to woodworking. 

however, for best cut quality and bit longevity, you may consider searching/buying those that have cutter geometry designed for wood, they aren't more expensive that i've found. when using them, experiment with the "feed" rate of which you're feeding the material, and rpm or "speed" of the cutter. in the cnc world, there is a whole science dedicated to _speeds and feeds_ associated with router bits when trying to maximize cut quality and bit longevity.


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## woodnthings (Jan 24, 2009)

*I stumbled across this video ....*

Can you use router bits in the drill press? That's sorta the inverse of the original topic, but may be of some interest?


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## kwoodhands (May 1, 2020)

The speed control only worked at full speed with the soft start routers I was told.
mike


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## Tool Agnostic (Aug 13, 2017)

Rhidium said:


> That's interesting.. What did the speed control do to the soft start routers that made it not work? It didn't slow it down?





kwoodhands said:


> The speed control only worked at full speed with the soft start routers I was told.
> mike


Soft-start routers have an on-board processor (computer) that monitors and controls the speed of the motor. 

-> The old-style router speed controllers change the input power in a way that damages those soft-start computer-controlled routers.

Soft-start routers do more than just soft start. They offer on-router speed adjustments. In addition, the onboard processor continuously monitors the rotation of the router bit, maintaining a constant rotational speed even under varying resistance loads on the rotating router bit.

I am not sure I would use an old style router speed controller on a soft-start router even at full speed. You are likely to damage the router. The soft-start is, after all, a variable speed feature if you think about it. The router should have its own onboard speed control anyway.


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