Mill bits????

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jttheclockman

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OK I am reaching out to the metal working people here. I need an education in end mill bits. Let the class begin. :glasses-nerdy:

I am eventually getting back into my shop. I am almost sure of this.:)

As I have been away from my friends in the shop I have had many ideas float across my brain waves. Some I have been able to capture. :) I have some ideas to make some pen blanks from aluminum. Do not have a metal lathe and probably never will. But I believe I can do what I want to with a wood lathe. My question is this. I have carbide router bits and that is all I use. Good quality. I want to drill and also route grooves in the aluminum.

Would it be better to get a mill bit to do this?
Can a mill bit be used in a router--- what is the shaft sizes
What is the smallest bits I can get?
Where is a good place to get them?
What is the advantage if any of a mill bit over a router bit?
What precautions need to be taken?
Is there a huge difference in the amount of flutes per bit and what is optimal?

Thanks to all the teachers beforehand and no there will be no apples given out.:)
 
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Dalecamino

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I have my bits for this very purpose only my router will be mounted on my metal lathe. I just haven't taken the time to do any purposeful work with it. But, it's coming soon.

I rounded up several bits as well as an adaptor for some of the smaller ones (to fit the 1/4" chuck) If I can remember where I found the bits, I'll let you know. It's been months since I bought them.:redface:
 

BSea

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I've bought a couple from Victor machinery. I can't help with your other questions.

Sorry.

I actually can answer all the other questions, but no apple . . . . no additional answers. :mad-tongue:

But don't worry, all my other answers would just be guesses.
 

Ed McDonnell

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My Answers / Opinions in RED below:

OK I am reaching out to the metal working people here. I need an education in end mill bits. Let the class begin. :glasses-nerdy:

I am eventually getting back into my shop. I am almost sure of this.:)

As I have been away from my friends in the shop I have had many ideas float across my brain waves. Some I have been able to capture. :) I have some ideas to make some pen blanks from aluminum. Do not have a metal lathe and probably never will. But I believe I can do what I want to with a wood lathe. My question is this. I have carbide router bits and that is all I use. Good quality. I want to drill and also route grooves in the aluminum.

Would it be better to get a mill bit to do this? I drill aluminum with regular drill bits. Grooves could be made with end mills, but other tooling may be a better choice depending on what you are planning. I don't buy aluminum specific end mills, but speed and feed are important to get good results and reasonable tools life.

Can a mill bit be used in a router--- what is the shaft sizes. I use end mills in routers all the time for wood. For pen size projects I like 1/8" shank mills. There is a wide selection of shank sizes and you will be able to find something that will work with whatever collets you have. Routers spin a little too fast for aluminum in my opinion, but it can be done if you don't care about tool life or cut quality. Handholding the router with aluminum is not something I would recommend.

What is the smallest bits I can get? The smallest I've used had a 0.001" tip (a 10 degree engraving bit). You can get end mills really really small (lots of micro tooling available). Being able to do anything with them without breaking them is another story. :eek:

Where is a good place to get them? Enco sells reasonable quality general purpose carbide end mills for the home shop. I wait and buy when they have sales (pretty frequent). There are a number of tool makers that sell really nice end mills at astronomical prices. You might want to wait until you get that Boeing contract before ordering any of those though. :biggrin:

What is the advantage if any of a mill bit over a router bit? I've gotten good results with end mills on wood. I have not gotten good results with router bits on aluminum. The cutting angles and chip clearance on router bits aren't optimized for metal.

What precautions need to be taken? Any vibration will quickly result in broken bits. Feeds and speeds are critical for cut quality and bit life. Hand holding a router will result in a lot of broken bits (and maybe worse problems) and lousy cuts. Aluminum powder is flammable and conductive. If you are generating dust because you are using the wrong speeds / feeds, you are looking for trouble. Aluminum chips bouncing into an electrical outlet can get exciting. Don't leave power strips laying around near your work area. Metal chips are sharp and shiny. They will get tracked in the house at some point. If you don't live alone, your better half may find metal chips a couple orders of magnitude more annoying than wood chips.

Is there a huge difference in the amount of flutes per bit and what is optimal? What is optimal will depend on what you are trying to do. More flutes requires higher feed / lower speed to avoid burning up the bit. Too much feed breaks the bit. I use 4 flute end mills on wood and really high feed and speeds. I use 2 flute end mills on my mill on metal more than I use 4 flute end mills. I use 1 flute engraving bits on my mill on metals and resins more than anything else.

Thanks to all the teachers beforehand and no there will be no apples given out.:)

I certainly wouldn't call myself an expert, but I seem to be able to do what I want in aluminum. That doesn't mean I couldn't be doing it better though. I look forward to seeing what other answers you get.

Ed
 

mredburn

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Yes a mill bit can be used in a router, The come in all sorts of shaft sizes. You can find them with 1/4 shafts and stepped down.. You may be just fine with a carbide router bit depending on what you want to do. I buy Carbide ball and end mill cutters with 1/8th in shafts that taper down to .1mm
You might check Ebay under "carbide end mill" and enter the size your needing for single bits. Or "micro carbide end mill" You can buy special collets for some routers like Porta Cable that have minimum runout and come in 1/4 and 1/8 collet sizes.
You may also have to buy a longer shaft cutter to get out far enough to cut.
 

TLTHW

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I use routers on aluminum all the time. Carbide cutters, lots of cutting fluid, Variable speed router with the speed turned down, super slow feed speed to allow the cutter to cut and clean out. I use bearing bits or templates and template guides. If I was going to use an end mill I would lock the router in a table and jig up the piece. on a lathe you would want to build a jig that allows the router to slide with a minimum of slop. I believe a couple of members have posted pictures of jigs they have built for using a router with their lathe.
 

skiprat

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In my humble opinion, I prefer to use router bits in a high speed router and milling bits in a low speed milling machine.
But I think the most important item is the control of a rigid, smooth and steady feed between the cutter and the workpiece.
If you can accomplish the control, then either option will work.

I doubt you can get good control by hand, so maybe look at a compound table ( xy table)

That is the method I used before I had a metal lathe or milling machine.

Good luck.:wink:
 

oneleggimp

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OK I am reaching out to the metal working people here. I need an education in end mill bits. Let the class begin. :glasses-nerdy:

I am eventually getting back into my shop. I am almost sure of this.:)

As I have been away from my friends in the shop I have had many ideas float across my brain waves. Some I have been able to capture. :) I have some ideas to make some pen blanks from aluminum. Do not have a metal lathe and probably never will. But I believe I can do what I want to with a wood lathe. My question is this. I have carbide router bits and that is all I use. Good quality. I want to drill and also route grooves in the aluminum.

Would it be better to get a mill bit to do this?
Can a mill bit be used in a router--- what is the shaft sizes
What is the smallest bits I can get?
Where is a good place to get them?
What is the advantage if any of a mill bit over a router bit?
What precautions need to be taken?
Is there a huge difference in the amount of flutes per bit and what is optimal?

Thanks to all the teachers beforehand and no there will be no apples given out.:)
Would it be better to get a mill bit to do this?
I believe so. The way that they are ground is different than router bits.
Can a mill bit be used in a router--- what is the shaft sizes
Yes you can use a mill cutter in a router if the shank size is correct. Having said that you should use it in variable speed router with the availability of very slow speed. Milling machines have much much slower spindle speeds than routers to.
What is the smallest bits I can get? I think you can get 1/8" cutters with a 1/4" shank
Where is a good place to get them? [COLOR="red" An industrial supply warehouse. Grainger is pretty ubiquitous through the U.S. and does carry mill cutters - at least here in Michigan[/COLOR]
What is the advantage if any of a bit over a router bit? Mill cutters are designed to cut metal whereas router bits are designed to cut wood and plastics.
What precautions need to be taken? [COLOR="red"][/COLOR] Run slow. Lubricate the bit.
Is there a huge difference in the amount of flutes per bit and what is optimal? You can get mill cutters in 2 and 4 flute - the difference between them and router bits is the angle of attack.
 

BRobbins629

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Ditto what others said
I tend to cut aluminum very slowly when using small bits, some as small as .5mm with 1/8 shaft. I make many passes perhaps .005" or less.

Also good idea to use cutting fluid designed for aluminum. Many alloys can be gummy so you may want to look for machineable ones if that causes trouble.

Still waiting to see your to do list!
 

jttheclockman

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I'm going to say "NO" then. You should know, though, I don't know the first thing about end mills. I just don't want to be in a agreement with Ed and Mike.


At this time I would like to thank everyone for their insights especially Derek:biggrin:

I will say this then. I think I will give the router bits I have a try first. I have the VS router. I have the means to support it and control it. I have the lubricant. I have the desire. I now have the knowledge. All I need is the ability to get in there and do something.

Bruce, my list continues to grow with each passing day. There will not be enough time in my lifetime to complete it but I hope to give it a try.:)

Thanks again everyone.
 

Paul in OKC

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You can, but the rpm that a router runs is faster than what most end mills are designed to run. Will they work? Yes. Like Skippy said, rigidity is the key. Controlling the feed rate is the next key. Lots of folks use WD40 on aluminum with success. Small end mills can build up faster than larger ones and give a bad cut at best, or break, so lubrication is a must.
 

D.Oliver

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I will say this then. I think I will give the router bits I have a try first. I have the VS router. I have the means to support it and control it. I have the lubricant. I have the desire. I now have the knowledge. All I need is the ability to get in there and do something.


Thanks again everyone.
I can't wait to see what you've got cooked up!
 

jttheclockman

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I will say this then. I think I will give the router bits I have a try first. I have the VS router. I have the means to support it and control it. I have the lubricant. I have the desire. I now have the knowledge. All I need is the ability to get in there and do something.


Thanks again everyone.
I can't wait to see what you've got cooked up!

Me too Derek:biggrin:
 

skiprat

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Let us know how that goes please Chuck. I'm still a bit sceptical about lubes on soft metals. I guess cos i cant understand the real need.

Coolant is used to keep the tool from overheating and getting ruined.
Lube is used to stop the chips building or welding up near the tool cutting edge.
Mixtures of both do both jobs
The constant flow of either does both and also washes away the chips.

But in my experience with soft metals, i have found that just a periodic spray of lube actually makes all the chips stick around. Doing the actual cut is okay, but when you back out the cutter ( from conventional to climb milling) the swarf in and around, actually is stuck in place by the lube and mars the milled surface.

I am probably doing it wrong, but find that just the speed of a router bit is enough to blow away the unlubed chips.

But of course, aluminium is not my favourite material, so i dont use it much.

Keep us posted please
:wink:
 
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TLTHW

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There is a cutting fluid called A9 that is specificly for aluminum. Cutting wax works to
Thanks Dave! I just received 3 4 oz. bottles from Fastoolnow. I've been using Relion for turning but, I thought I'd give this a try.:wink:
I like it better than WD-40 for routing, turning, and milling. I haven't used Relion. I still prefer cutting wax for sawing thin stock. Over 1/4" thick I wax the blade(often) and will run wax or A9 down the cut path before I start.
 

Dalecamino

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Let us know how that goes please Chuck. I'm still a bit sceptical about lubes on soft metals. I guess cos i cant understand the real need.

Coolant is used to keep the tool from overheating and getting ruined.
Lube is used to stop the chips building or welding up near the tool cutting edge.
Mixtures of both do both jobs
The constant flow of either does both and also washes away the chips.

But in my experience with soft metals, i have found that just a periodic spray of lube actually makes all the chips stick around. Doing the actual cut is okay, but when you back out the cutter ( from conventional to climb milling) the swarf in and around, actually is stuck in place by the lube and mars the milled surface.

I am probably doing it wrong, but find that just the speed of a router bit is enough to blow away the unlubed chips.

But of course, aluminium is not my favourite material, so i dont use it much.

Keep us posted please
:wink:
Will do Steve. I'm hoping it will help make a smoother cut than I got with my test passes. The bottle says "apply a drop to the material surface and the cutting tool and, continue as needed". I wasn't aware of all you've stated in your post. So, I'll pay close attention to what's happening when I give it a try. Thank you for the help and, I'll let you know what I find.:wink:
 

Dalecamino

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There is a cutting fluid called A9 that is specificly for aluminum. Cutting wax works to
Thanks Dave! I just received 3 4 oz. bottles from Fastoolnow. I've been using Relion for turning but, I thought I'd give this a try.:wink:
I like it better than WD-40 for routing, turning, and milling. I haven't used Relion. I still prefer cutting wax for sawing thin stock. Over 1/4" thick I wax the blade(often) and will run wax or A9 down the cut path before I start.
I won't be doing any sawing. Just carving! :biggrin::rolleyes:
 

Dalecamino

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I can't believe this was 3 years ago. Thanks for bringing it back into the light. I never did find a way to build the articulating arm Steve showed me. So I pretty much gave up on that idea. The flutes with my router never really developed either. They didn't look good to me, and I believe I may have been routing in the wrong direction.

I have plenty of aluminum, and when power is restored to the shed, I should check that out.
 

jttheclockman

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Well have to say life got in the way and I never followed through with what I had planned. I bought some router bits to try for my project so I am not sure how well they will work But being I am able to get back into my shop and have a few projects going now I probably will get to this one as well. If i can clone myself I could get more done. :biggrin::biggrin:
 

CREID

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Well have to say life got in the way and I never followed through with what I had planned. I bought some router bits to try for my project so I am not sure how well they will work But being I am able to get back into my shop and have a few projects going now I probably will get to this one as well. If i can clone myself I could get more done. :biggrin::biggrin:
Oh God no!!!!!! Don't clone yourself. We can't handle another one. :biggrin::biggrin::eek:
 

jttheclockman

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Well have to say life got in the way and I never followed through with what I had planned. I bought some router bits to try for my project so I am not sure how well they will work But being I am able to get back into my shop and have a few projects going now I probably will get to this one as well. If i can clone myself I could get more done. :biggrin::biggrin:
Oh God no!!!!!! Don't clone yourself. We can't handle another one. :biggrin::biggrin::eek:
He would be the Ying to my Yan:biggrin::biggrin:
 

Terredax

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To answer your question... yes mill cutters can be used in a router.
As mentioned, the router runs at a much higher RPM than a mill or spindle, even using a VS router on it's slowest speed. So when using a router, use a single flute mill as opposed to a higher flute. This allows the chips to be evacuated to reduce heat build up. The chips carry away the heat. A flow of compressed air will help with both of these as well. The higher flute mill cutters are intended for the very slow RPM of a mill or spindle. If cutting aluminum, there are specialty cutters just for that. They are worth the cost.

Next is feed rate. Every manufacturer lists their chip loads and feed rates as a starting point. If the feed rate is too fast, you create dust and the heat builds up. If you go too slow, the cutter isn't cutting, and the heat builds up from friction against the walls of the cut. The goal is small chips.

Another thing to keep in mind, is the plunge or Depth Of Cut (DOC). The DOC shouldn't exceed half of the diameter of the cutter in a pass. This helps eliminate heat, flex, and breakage.

Precautions would be the same as using any other power tool. Be aware, that a mill cutter that is spinning at 8,000 RPM and breaks, happens very quickly. That flying piece of sharp, hot metal will cause damage to anything in it's path. Wear protective gear, and follow the recommended feed, plunge, and chip loads. Attempting this by hand can be dangerous, as one can not possibly control all aspects of these parameters at the same time.

It's hard to cover everything but, that is the basics.

Also, a carbide router bit can be used on non-ferrous materials. Mill cutters are mostly solid carbide of varying grades for different materials.

Be safe, and I look forward to seeing your outcome.
 
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eharri446

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I got two sets of end mill bits from Amazon. The first set started at .6mm and went to 1.6mm. The second set started at 1.5mm and went to 3.187mm or 1/8 inch. they were all 3.187 mm shanks which is the same as 1/8 inch. They were each around $10 - $15 per set. I also order a set of 10 1/8 inch carbide end mills in various shapes for $20.00.

I have a mini CNC machine that my oldest son got me that I am using 1/32 - 1/8 inch up cut carbide cutters that I ordered from Inventables.com for about $9 each. They all have 1/8 inch shanks.
 
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