End Mills?

[Mike Wenman]

I did a search on end mills throughout the forum and came up with several posts on wood mills, saw mills, tons of pepper mills and even a flour mill, but relatively little on end mills.

Now as you may have read my Acme Lead Screw thread, I am going to venture into this CNC Router hobby and as I mentioned in there, I have a 1/4" dia 3-1/2" long 2 flute end mill and am sure that this will be good to get a basic working knowledge down to rough things out, but trying to keep costs down now, I would like to come up with a general concensus on what 3 or 4 end mills would be a good to have to get thing started.

I have read about 2 flute, 4 flute, and know that there are flat, 60 deg, ball mills out there so to give you an idea of what I"ll be doing with this other than just cutting out flat parts (ie, re-cut a new table / gantry to true things up a bit), I am very interested in doing plaques and signs like many of you do and intrigued with photo V Carve.

So, there ya go. As mentioned, I am trying to keep my costs down so I won't end up sleeping in the bathtub :P

Mike
USN Ret.

[Gerry Grzadzinski]

The term end mill typically refers to metal cutting tools. Router bits for wood, are called, router bits. :) Although endmills for metal will work, router bits are designed to cut wood, and have different cutting edge geometry, and larger flutes to remove the larger chips. You won't find any 4 flute spiral router bits, because you really can't cut fast enough to take a big enough cut with each flute. Ideally, for maximum tool life, there is a recommended chip load (thickness of cut per flute) for a specific tool. Cutting less than the recommended chip load will result in shorter tool life.

It's very difficult to recommend what bits to use, as ideally, specific jobs require specific tools. If you're on a budget, buy carbide tipped straight bits. Much cheaper than solid carbide spirals, and will cut just fine while your learning. Some companies make CNC specific carbide tipped bits, designed for ore aggressive cutting than normal.

One thing to consider, especially with smaller diameter bits. You're 3-1/2" 1/4 bit is really long. For best reults, try to use the shortest bit you can. You'll get less tool deflection, cleaner cuts, and a lot less noise. Long 1/4" bits can really scream sometimes.

If you're doing 3D carving, you'll want some ball nose bits. Standard carbide tipped core box bits work very well to, and are much cheaper. The size required depends on the level of detail required.

For V carving, again, size will dictate the tool required. Large letters will require larger angle tools, up to maybe 120°, and small letters might require 30° or 45° bits. It really depends.

Again, I'd just grab some inexpensive 2 flute router bits and start using those. You can always buy some spirals and try them out as needed.

[Keith Outten]

I agree with Gerry for the most part but there are times when an end mill is a good choice for routing. I own a milling machine and a metal lathe so I have an assortment of end mills in my tool box.

Two flute end mills are generally cheaper than router bits and they are almost always more precise and smoother cutting in spite of the slight difference in cutting geometry. When I ordered new collets for the Porter Cable router motor in my ShopBot I ordered 1/4", 3/8" and 1/2" collets because a lot of good end mills are 3/8" diameter and they cut plastics and Corian like butter and near last forever. These are great for inlay work because a 3/8" end mill is normally 0.375" in diameter and router bit sizes vary quite a bit.

I haven't used ball nose end mills yet in my ShopBot but I wouldn't hesitate to try them.
.

[Peter Meacham]

Keith

Would you share your source and part numbers for the collets and bits you use for plastics and Corian pls. I cut Corian but probably don't get the quality of cut that you do.

Thanks, Pete

[Bob Savage]

Yeah, come on Keith, I'm getting closer to having router motors spinning, so spill the beans. :)

[Tom Sharum]

Hey guys I'm glad someone started a thread on this subject. I am a CNC newbie. I just ordered a small CNC unit (24x32) and man do I have a lot to learn yet before I can operate that little gem. So while we are on the subject of end mills can someone direct me to a website or book where I can learn all there is to know about end mills? Like application, feed rates, what size bit will do what, and so on. I will use my CNC router for detailed 3D wood carving and maybe some joinery and making curved moulding. I have read the CNC Cookbook already and it tells nothing. Please help

[Robert Alexander]

Hey guys I'm glad someone started a thread on this subject. I am a CNC newbie. I just ordered a small CNC unit (24x32) and man do I have a lot to learn yet before I can operate that little gem. So while we are on the subject of end mills can someone direct me to a website or book where I can learn all there is to know about end mills? Like application, feed rates, what size bit will do what, and so on. I will use my CNC router for detailed 3D wood carving and maybe some joinery and making curved moulding. I have read the CNC Cookbook already and it tells nothing. Please help

Tom you have asked the holy grail question of CNC. Router bit feeds and speeds. This web page can give you a start. Just click on the bits list and on the last page you will find some good information to start with. It help me alot. I used the formula for figuring out the speeds and feed rates for my machine. And I am getting good cuts with my end mill bits.
http://www.hartlauer-bits.com/products.html

[Steve knight]

I don't think I have noticed much difference between endmills and upcut rout bits from several sources. but now I use mostly downcut so endmills are out. centurion bits are very cost effective over endmills so I jsut use them. http://www.centuriontools.com/router_bits_toolcase/index.html?cart=1205519234587759

[Keith Outten]

Sorry for the delay responding, I have been working at CNU all weekend installing signs. On top of the extra hours this week I have contracted a cold and I am feeling pretty bad but the final inspection for the new building is Wednesday and I received extra work to do at the last moment.

When I purchased my metal lathe from a friend of mine it came with a rather large box of end mills. I also had acquired a pretty good assortment of end mills through the years from friends who worked at machine shops. The times when I have purchased end mills I bought them from a local company so I haven't had to order them online or from a catalog yet.

I checked my end mill inventory and I have some ball end mills in several different sizes, all of them are two flute. I have been using 1/4" and 1/8" straight cutters in my ShopBot since I got the machine and of course a variety of router bits. The router bits I have been purchasing lately are from Centurion Tools in Louisa County Virginia. Centurion makes end mills and router bits for CNC machines and they are unbelievably sharp. I purchased a set of solid carbide vcarving cutters from them when we did a bulk buy here at The Creek. I save these for detailed work where I need a very fine smooth cut and don't want to deal with fuzzies.

Centurion Tools makes the best cutters I have ever seen, a lot of people who visit the ShopBot Forum are purchasing from them and I was able to meet the President of their company at a user group meeting last year. I haven't done a lot of 3D work yet but the jobs I have done in Corian were done with a set of 1/4" and 1/8" Centurion ball end cutters that were 20 bucks each. I know a couple of guys who have had Centurion produce special cutters for some problematic materials.

A lot of people purchase end mills from Enco because they have the lowest prices and pretty good quality.

Check out this link for precision collets:
http://www.precisebits.com/products/equipment/pc_collets_nuts.asp
.

[Gerry Grzadzinski]

https://www.onsrud.com/xdoc/FeedSpeeds

[Bob Savage]

This is an excellent and for me, a timely thread. Tomorrow I'll be getting online and buying bits...

[Michael Schwartz]

end mills can also work nicely in a horizontal mortiser for some applications.

[Bob Savage]

Since we're on the topic of bits, do any of you have recommendations on ogee bits for use on a CNC? Most seem to have the ballbearing on the bottom, although I did find some Amana ogees for CNC cutting, on Amazon.

Edit: Looks like Magnate has loads of ornamental bits.

[Steve Stram]

I had been told by a machinist and also read somewhere that end mills were made to operate at a much lower rpm than router bits. Part of that is they were being made for metal.

I asked the question and looked it up due to the end mills being more inexpensive than router bits.

Looking up metal mills I found that 4,500 rpm was at the upper end. The Bosch Colt will spin to 35,000 rpm. So using a metal end mill could end up spinning it at 7 times the rpm it was designed for.

Is there any safety issue with this? Am I just paranoid?

Has anyone ever gotten a response from end mill company on this?

Steve.

[james mcgrew]

bob, some may differ with me on this but i would not recommend to anyone new to cnc to ever use a bit with a bearing on it.

later today i will compile a starter list,

for now get some of the following

spiral down or up 1/4" carbide endmills 2 flute carbide

spiral down or up 1/2" end mill 2 flute carbide

"v" bits .5 diam 60 and 90 degree, any good tool store

i think i saw where micheal swartz posted about 1" and 1.25" v bits and they are real nice to have for large sign work.

1/8" taper ballnose (beckwith decor sell some good ones of all of these)

[Scott Shepherd]

Steve, there isn't a problem running end mills at high rpm's. You need to understand where all these "CNC routers" are coming from. They are replicating what was done 30 or more years ago in the CNC world. Compared to metal cutting CNC milling machines, many of the routers are made with cost being the number one focus, so they can get routers into consumers hands.

There didn't use to be high speed spindles on CNC milling machines. If you had a mill that would turn 3,500, you had something and you paid a lot for it. The reason wasn't because they didn't need to run that fast, but it was probably 2 fold, one is because those machines held .0001"-.0003" on repeatability and positioning. They used closed loop servo systems to accomplish that. But servos and glass scales were all in the early stages. So you couldn't start and stop but so fast and maintain accuracy. If you can only cut at 75 inches per minutes, then no need to have a 15,000 RPM spindle.

Second, a CNC milling machine has a very advanced spindle setup. Oil circulates through the head and the bearings. It has to do this to maintain the temperature. When the head gets hot, everything grows, so if you didn't cool it, as it got hot, your cut would get deeper. And when you're holding tight tolerances like CNC mills frequently do, you can't have your machine moving around because of temperature. So that posed a real challenge. How do you run a spindle at 10,000 RPM and keep it cool.

They resolved all of that over time and in the late 80's, early 90's, you started seeing the advent of "High Speed Machining". That meant milling aluminum at feed rates over 100 inches per minutes and it meant 10,000 RPM and more.

The problem came into the equation where all the tool holders, which had a Cat 50 taper on them, were made for lower RPM machines. You're talking about a tool holder and retention knob that weighed 10 pounds or more. You spin that at 12,000 RPM and you'll have balance problems. So they came out with special tool holders and special retention knobs for the tool holders that were all balanced and made for high speed machining.

Most of this was happening in the aerospace industry. They were high speed machining aluminum in a big way.

In the end, it drove the entire industry to make things that were high speed ready. You are fine with running an endmill at high speeds. You just need to make sure you aren't exceeding it's recommended surface feet per minute speeds in the RPM side and you'll be fine.

There is very little difference in what you call "router bits" and what everyone in metal side calls an "end mill". There may be some slight geometry differences, but most likely you'd have to be a power user to know or see the difference. What router owners call "up spiral" and "down spiral", we call by the technical terms of "right hand helix" and "left hand helix". Also know that Centurion made end mills for a living and still do. I had an interesting conversation with Fred at Centurion last time I went by there about all of this, and how router folks have renamed things that already existed for years and how confusing it had become.

I can't speak for wood, because I don't cut it often, but in the rest of the industry, machinists have been cutting plastics, metals, and everything in between for over 100 years now. No need to reinvent the wheel. Build on what they have already done and you'll be light years ahead.

p.s. I worked for the company that invented and patented the first FMS (Flexible Manufacturing System). I also worked at a place later on that had 40 CNC machines, almost all robot loaded, and we even had several that would change setups, change chuck jaws, change all their own tooling, and also measure the parts and make adjustments as it was going. Very cool stuff.

[Bob Savage]

bob, some may differ with me on this but i would not recommend to anyone new to cnc to ever use a bit with a bearing on it.[quote]

Yep, I figured this due to the possibility of running the tool into the material to the point that there's a load on the bearing. Seems like that could be nasty... plus accidentally plunging into material could be a problem, eh? :D

[quote]

for now get some of the following

spiral down or up 1/4" carbide endmills 2 flute carbide

spiral down or up 1/2" end mill 2 flute carbide

"v" bits .5 diam 60 and 90 degree, any good tool store

i think i saw where micheal swartz posted about 1" and 1.25" v bits and they are real nice to have for large sign work.

1/8" taper ballnose (beckwith decor sell some good ones of all of these)

Here's what I ordered a couple days ago.

1/4 COMPRESSION 1-1/8" CUT LENGTH
1/8" BALLNOSE
1/4" BALLNOSE ENDMILL 1-1/8" CUT
1/4 X 90 DEG V-CARVE BIT
1/2 X 90 DEG. V-CARVE BIT
1/4" X 60 DEG V-CARVE BIT 2" LENGTH
1/2 X 60 V-CARVE BIT
1/8 UPSHEAR 5/8 CUT LENGTH
3/16 UPSHEAR 3/4 CUT LENGTH
1/4 UPSHEAR 1-1/8 CEL
1/2 UPSHEAR 1-1/8 CUT LENGTH

Magnate 7502 Point Cutting Roundover Router Bits
Radius: 3/8"; Shank Diameter: 1/2"; Cutting Length: 5/8"; Shank Length: 2"

Magnate 7501 Point Cutting Roundover Router Bits
Radius: 1/2"; Shank Diameter: 1/2"; Cutting Length: 3/4"; Shank Length: 2"

Magnate 7503 Point Cutting Roundover Router Bits
Radius: 1/4"; Shank Diameter: 1/4"; Cutting Length: 1/2"; Shank Length: 1-1/4"

Magnate 3931 Classic Plunge Cutting Router Bits
Radius: 3/32"; Cutting Diameter: 1/2"; Shank Diameter: 1/4"; Cutting Height: 3/8"; Shank Length: 1-1/4"

Magnate 3306 Mortising Router Bit
Cutting Diameter: 1-1/4"; Cutting Height: 3/4"; Shank Diameter: 1/2"; Shank Length: 1-1/2"

[Steve Stram]

Steve, there isn't a problem running end mills at high rpm's...

Scott,

I really appreciate your time and details in response to my question. That was the information that I was looking for and am now content to use end mills as an additional source of tooling.

The real end mills (Grainger) that I have, seem to be beefier than the router bits sold in woodworking stores. I was using them at 2,500 rpm in a drill press for putting holes in aluminum.

Thanks again.

Steve.

[Guy Mathews]

Picked up from Scott the following quote and would like to reiterate what I have been saying.

"There is very little difference in what you call "router bits" and what everyone in metal side calls an "end mill". There may be some slight geometry differences, but most likely you'd have to be a power user to know or see the difference. What router owners call "up spiral" and "down spiral", we call by the technical terms of "right hand helix" and "left hand helix". Also know that Centurion made end mills for a living and still do. I had an interesting conversation with Fred at Centurion last time I went by there about all of this, and how router folks have renamed things that already existed for years and how confusing it had become.

I can't speak for wood, because I don't cut it often, but in the rest of the industry, machinists have been cutting plastics, metals, and everything in between for over 100 years now. No need to reinvent the wheel. Build on what they have already done and you'll be light years ahead.
"

Scott,

Well said. I have said this before and I will say it again. No... not the magic button phrase, the other one. This is not rocket science no matter how much certain companies want it to be. Find out how they did it before CNC and you have 75% of the hard stuff out of the way.

My understanding of the terms "end mill" and "ball mill" is that the tip or end of the tool is designed to do the cutting. Flutes describe the side cutter and channel that run the length of the cutter.

Having added my 2 cents to this debate I leave you with one last Christmas present. The half inch and 1/4 inch ball mills that I use on our 10 spindle carving machine are designed for cutting metal, not wood. What do we cut with them? You guessed it, wood! Why, because these bits last us longer then the so called ones that are designed for cutting wood. Go figure!

Like Scott said, don't reinvent the wheel. Use what you have on hand by knowing how to use it. Yes, even bits that have bearings on them! Before you do, learn how to do it! If you are uncertain, you are welcome to shoot me an email. I shoot folks emails all the time asking how to cut certain things I have never cut before. Today I just milled 4 inch thick cork. Yes cork! It milled beautiful and was clean and smooth when the cut was finished. Didn't know if it would work or not, so me and the customer slapped a piece on the machine and ran a program! Its that easy.

Scott... Thanks for your post.

Merry Christmas Creekers!!!!!

[Bob Savage]

Another great SMC thread.

Guy/Scott, do you have a preference on end/ball mill MFG's and/or vendors?

[Michael Schwartz]

i think i saw where micheal swartz posted about 1" and 1.25" v bits and they are real nice to have for large sign work.



Yes the starter bit set I got with my bot came with a 1" diameter 60 degree V bit from Onsrud and it is quite versatile. since you can go from engraving with its very fine point to deep lettering.

[Scott Shepherd]

Another great SMC thread.

Guy/Scott, do you have a preference on end/ball mill MFG's and/or vendors?

I do not. I've not cut anything with a ballnose other than a groove around a cheese board :) That's not the type of work I do (3D profiling). You have to also keep in mind that cutters used to be all High Speed Steel. Carbide wasn't widely used in milling for several reasons, which I'll go over at some point in another thread when I have more time. High Speed Steel will flex and give a little and is much more forgiving to deflection. Carbide seems to be the "normal" for everyone now, and it's very unforgiving. It is very brittle and doesn't deflect much before it snaps. You can take a carbide end mill that runs out .001" because of a bad collet or spindle and it'll snap it off. That used to be the rule. Not so much any more.

We always used OSG endmills for most everything, with some Fette (sp?) thrown in there for tougher materials. However, those were mostly high speed steel.

There also seems to be an obsession with 1/4" shank cutters. I agree with Keith's earlier post, get into the 3/8" world. Lots more options. I even see 1/2" shank, 3/8" diameter cutters. You're doing nothing there but paying for extra carbide for the larger shank. It gives no additional strength or cutting ability.

So far, with the router, we've used mostly Centurion cutters. Why? Because we can drive to them and pick them up :)

[Guy Mathews]

Bob,

To add to what Scott said. HSS (High Speed Steel) was recommended to me by our local machine shop when I first cut aluminum for my CAMaster A axis mod. that I did. I was told by the owner that the HSS actually slices the aluminum where carbide tears it. Carbide for all its wonderful praises can chip and shatter if it taps metal the wrong way or is dropped.

Most of the bits I buy come right from Onsrud. They changed their website the other day and I have to say it is a little disappointing. The old site was much better.

Anyhow, the starter set from ShopBot was and is a good deal. As far as the other bits go, I have a furniture shop that is full of router bits of every shape and size and I use them on my CAMaster at 15000 rpms, standard. I listen to my bits and adjust my feed speeds in my programs accordingly. Wood is non-consistent and every piece will mill differently therefore I have come up with a good average rate for most of MOPS.

I would suggest you add a half inch ball mill to your collection to use for roughing operations. The ball mill will leave ridges that keep the material from tearing out below your next surface cut. End mills work for roughing but can pull out wood especially on relief carvings and 3D work on a 4th axis.

Basically, if you can run a bit in a router for wood, you can run it on your CNC machine for wood. You can also use other types of bits and you are only limited by your experience and willingness to try something.

These are great machines, but when it comes right down to it, they are nothing more then glorified routers!

CAMaster built me a really nice glorified router with a spindle and ATC!!!!!

If you are still wondering which bits to use and what to spend on them aske yourself this question.

Would you buy a cheap bit for your router or a cheap blade for your tablesaw?

TTYL, the kids are getting home from school and I need to meet them at the bus!

Guy

[Jerome Stanek]

You also will need a good surfacing bit.

[Jerome Stanek]

You will also need a good spoilboard surfacing bit

[Bob Savage]

Thanks for all the input, Scott and Guy!


You will also need a good spoilboard surfacing bit

I bought this for spoilboard surfacing. I realize it won't be as fast as "real" spoilboard bits, but the bits I've seen for SB surfacing are $250 and up.

Magnate 3306 Mortising Router Bit
Cutting Diameter: 1-1/4"; Cutting Height: 3/4"; Shank Diameter: 1/2"; Shank Length: 1-1/2"

Any thoughts?

[Steve knight]

you can get a 1.75 mostising bit from amana for around 40.00 or less.
myself I use mostly downcut bits. fopr solid wood they cut the cleanest of any bits with little or no blowout. for sheet goods they can be handy to keep parts in place.

[Bob Savage]

you can get a 1.75 mostising bit from amana for around 40.00 or less.
myself I use mostly downcut bits. fopr solid wood they cut the cleanest of any bits with little or no blowout. for sheet goods they can be handy to keep parts in place.

Well that figures... though, I *did* hear that before, and searched for it, and couldn't find where to actually buy it. Any links? That also figures about the down cuts. Looks like I might end up buying some once I start tearing out the edges of my work with the upspirals. :)

[Michael Schwartz]

I used the bit included with the ShopBot starter kit which is a 1.25" diameter bit from onsrud and It didn't take long at all to mill the spoil board. I ran two passes and I know for sure it took under an hour. So Whatever 1.25" bit you got Bob should work fine.

[Steve knight]

Well that figures... though, I *did* hear that before, and searched for it, and couldn't find where to actually buy it. Any links? That also figures about the down cuts. Looks like I might end up buying some once I start tearing out the edges of my work with the upspirals. :)

here you go. I like to use downcuts when i have a lot of small pieces on a sheet of ply. I can cut more on a sheet and I don't need tabs. I hate tabs they are easy to cause surface veneer tearing.
but there is a trick to it. the thinner the material the smaller the bit needs to be. and you have to be careful with multiple passes as that can remove too much sawdust. and there is more upward pressure on the z so it can bring out the slop in the machine. Plus if your spoilbord is chewed up you may get some blowout on plywood on the bottom side though it depends on the wood getting cut.


http://routerbitworld.com/ProductDetails.asp?ProductCode=AMANA%2045453&click=1680
http://routerbitworld.com/ProductDetails.asp?ProductCode=AMANA%2045480&click=1680

[Andy Tripp]

Bob,
Over the years I have used numerous profile bits (that had a bearing) on a CNC.

2 tips that will have to be followed:

1. remove the bearing and grind the post down - if you don't have that ability, maybe a tool supplier can do that for you. I have a local one that has done several for me.

2. This profile bit is not designed to plunge into material so you will need to make a pass with a straight bit to "get material out of the way" to make room for the profile bit.

Andy

[Leo Voisine]

Mike,

I am a manufacturing engineer. I work with CNC machines in metal cutting all day every day.

I also have a small CNC router at home. It's not a high end router but it's not home made either.

It is true - that end mills and router bits have different cutting geometry's. However, just about any end mill with 2-3 flutes designed to cut non-ferous metal will work well on wood.

The fewer the flutes the greater the gullet in the end mill. The gullet allows for chip evacuation.

There are significant advantages to using an end mill over a router bit also. Presicion, sharpness, geometry variations and availability. You can get a "stubby" 1/4" diameter 2 flute aluminum cutting SGS end mill, that will blow your socks off in performance.

You also need to know that carbide it brittle and breaks very easily. However, in a solid CNC router, you can do some real fancy stuff.

I make branding irons on my router. They are brass. One of the tools I use is a 1/64 inch end mill. There is no chance on earth that you will use that tool by hand - but in a solid machine - yes.

Speeds and feeds -- this is pretty simple. However, getting the information is sometimes difficult - OR - very easy. It is as easy as a phone call to the tool manufacturer and ask for the technical departement - they will just tell you what to run at.

For me and my machine. My machine cannot handle 100 IPM. So I can run at 30-40 IPM in wood without too much difficulty. Going too slow will just burn the wood.

I have used ball nose end mills. They work for 3D stuff, but also for engraving.

For "V"-groove engraving I use a couple of different tools. MCLS has a nice "V" grooving tool, but I also use a Accupro Drill Mill combo tool from MSC.

For laminated plastic "name plate" stuff I use a "pyramid tool" from "bits & Bits" with a .005 diam tip.

Yeah - there's a lot to cutting tools.

[Joey Jarrard]

Here is a chip load calc it comes in handy for feeds and speeds.

[Mike Wenman]

I just placed an order wtih Centurion Tools for a 1/4" shank 7 bit start set which includes:

(3) 1/4" dia V-Carve bits of 60, 90, 120 deg and 3" length
(3) 1/8" cutters, 5/8" cut in upshear, downshear and straight
(1) 1/8" ballnose, 1/2" cut length on a 1/4" shank



I also have already a 1/2" shank 66 Piece router bit set from MLCS. Would some of those in there work as well for various items?

Mike

[Michael Schwartz]

I also have already a 1/2" shank 66 Piece router bit set from MLCS. Would some of those in there work as well for various items?

Mike

The other day I used a standard 1/2" straight bit with mortise end from Lee Valley to cut 4 double tapered legs out of 8/4" QSWO. It happened to the only bit I had on hand that was long enough and it worked just fine.

A sharp router bits a sharp router bit and a routers still a router, weather handheld or CNC!. If your using a cheaper bit I would plunge cut a hole, and measure the exact diameter to be sure since tolerances can differ.

[Guy Mathews]

I just placed an order wtih Centurion Tools for a 1/4" shank 7 bit start set which includes:

(3) 1/4" dia V-Carve bits of 60, 90, 120 deg and 3" length
(3) 1/8" cutters, 5/8" cut in upshear, downshear and straight
(1) 1/8" ballnose, 1/2" cut length on a 1/4" shank



I also have already a 1/2" shank 66 Piece router bit set from MLCS. Would some of those in there work as well for various items?

Mike

In a nutshell, Yes. Even the ones with the bearings on them. What you have to remember is that a CNC Router is a router that is moved by electro-mechanical means and not biological means. The human element comes from the programmer. Once you get more comfortable with your machine and your programming abilities, you will start to make specialized jigs to hold a piece just a certain way so you can create a profile with that one router bit that you have been wanting to try.

The bits that use a guide bearing at the end of the bit like an Ogee bit can be used. You just select a bit in your CAM that is equal in diameter to the bearing and run with it. The result is the same as if you used that bit in a handheld router. Now mind this, the wood should already be cut to the existing size you want to profile and fixed in place. The bearing will not cut and you can damage both machine and material if this is not done properly. Save those bits for now, and stick to profile cuts and carving until you get more of a feel for your machine and the programming.

The time will come for you soon enough.


In the meantime, "How do you get to Carnegie Hall?"

"Practice my friend... Practice!"

Guy

[Gerald Wubs]

note that you cannot plunge cut with a 4 flute end mill. They are not end cutting. 2 & 3 flute are. For wood, stick to carbide.

[Dan Hintz]

note that you cannot plunge cut with a 4 flute end mill. They are not end cutting. 2 & 3 flute are.
Care to explain why? I have no clue either way, but I thought the point of an end mill was to allow a cutting edge at the tip of the bit (i.e., plunge cuts), regardless of # of flutes.

[Rob Wright]

Care to explain why? I have no clue either way, but I thought the point of an end mill was to allow a cutting edge at the tip of the bit (i.e., plunge cuts), regardless of # of flutes.

I agree. All of the 4-flute mills I have purchased from Use-enco.com are center cutting:confused: I just had to pick center cutting end mills and not the non-center cutting mills....

[Scott Shepherd]

My guess on his statement was it was based on the viewpoint of a machinist. Historically, 4 flutes have not been center cutting. In the metal working world, you don't plunge with 4 flutes too often. The flutes are closer together and you can have chip removal problems, and 4 flutes were most often used on harder materials. You rarely used a 2 flute on finishing hard materials. It was less productive and time is money.

You could get center cutting 4 flutes, but you had to request them and most places didn't have them on the shelf.

However, with CNC grinders doing all the work now, a lot of people just make and carry all sorts of options. So the center cutting 4 flutes is much more available and visible today and than it was 15 years ago.

That's just my opinion on it. Might not be what he meant, but it's what I have seen.