# How not to attach an end mill to a small lathe



## yclo (Apr 20, 2007)

So I picked up a 4 flute end mill so that I can reduce the time spend on boring operations.






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I then proceeded to make what I thought would've been a workable end mill holder, one end I have threaded for screwing onto my tail stock. But it turns out the bore I made using the end mill for the end mill is actually larger than the diameter of the end mill itself. 

Right, so I thought to have more set screws so I could adjust the end mill until it is true. Then it turns out that the aluminium is not strong enough for me to tighten the screws on. Oh and did I mention that it takes really long to true it?  

The ideal I think is probably a holder threaded to accept the end mill on one end and can screw onto my tail stock. But that is beyond what I can handle on my tiny machine.

Anyone want to help me make one? :help:

-YC








bigger ............................................ bigger


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## scott.cr (Apr 20, 2007)

How are tools held into your tail stock? Just threaded in or is there a draw bar?

Have you considered putting a drill chuck in your tailstock? It's feasible to drill (not mill) with an end mill in a drill chuck.


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## modamag (Apr 20, 2007)

Drilling is much quicker than plungged milling.
Have you thought of making a sleeve instead. Similar to the boring adapter sleeve.
1. Bore a piece of aluminum.
2. Cut a slot all the way thru.


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## will (Apr 20, 2007)

how big is the lathe? I might be wrong - It looks to me that the setup is not big enough for a 5/8 " end mill.


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## PhotonFanatic (Apr 20, 2007)

yclo said:


> So I picked up a 4 flute end mill so that I can reduce the time spend on boring operations.
> 
> . . .
> 
> ...



Speaking from what little experience I have, I second the advice to drill, not mill, if you want to cut down on the boring time (no pun intended).

Is that the stock tailstock? Most tailstock have some method for holding drills, either a drill chuck or a Morse taper of some sort, as well as a way to advance the drill into the part.

I do not see any crank on your tailstock. How were you going to advance the endmill into the part?

BTW, that set-up is an invitation for disaster. You can't use screws to hold an endmill in place. As soon as that endmill started to dig into the piece, it would have been all over.


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## yclo (Apr 20, 2007)

Thanks for the advance on using a drill bit, I had thought that with an end mill I can get the flat in the end of the bore.

I had a feeling that the end mill wouldn't hold with the screws like that, but I wanted to try anyway since I have no other options. But it's a good thing that they didn't hold so I couldn't test it. 








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The tailstock is lever activated, and comes with the drill chuck that is in the photo above. The largest drill bit that can fit into the drill chuck is 7mm, it is a very small lathe. I've measured that with the end mill in place there will only be 120mm left between centers.

This is the other reason that I chose an end mill as drill bits this thick will be even longer, which will give me even less room to work with. And I still have the problem of attaching it to the tail stock.

-YC


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## PEU (Apr 20, 2007)

I have two chucks for the tailstock, one is similar size of your photo, the other is a massive piece of metal capable of holding a 3/4" tool, I use it when I want to use one of the big end mills.

OTOH, I find myself using less and less the endmills, I finally purchased a couple of professional insert holders ($35 each / www.schloher.com.ar) and now I understand many ppl told me its a one way route.
Now for making a long bore I drill a hole to the desired length, and then with the boring tool I go all the way to the bottom, it works sooo nice, FAR better than my old carbide tools. Yesterday was the last time, I bored some brass, it was like cutting butter with a hot knife.


Pablo, searching that company catalog for more tools 

_


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## Anglepoise (Apr 20, 2007)

Well it was worth a try and 'nothing ventured, nothing gained'.
However your lathe does not have the power to run a 5/8th Endmill into a revolving block of Aluminum. 
Send in a sharp,smaller drill to start to core out a hole. Then progressively move up in size until you are one size under the finished dimension.

Then use your smallest HS boring bar to face the bottom flat and true up the bore.

Make sure your drills are HS steel and very very sharp. Use WD40 or Kerosene as lube for Aluminum.

Good luck.


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## will (Apr 20, 2007)

Anglepoise said:


> Well it was worth a try and 'nothing ventured, nothing gained'.
> However your lathe does not have the power to run a 5/8th Endmill into a revolving block of Aluminum.
> Send in a sharp,smaller drill to start to core out a hole. Then progressively move up in size until you are one size under the finished dimension.
> 
> ...



+ 1 on that 

I also mix in a few drops of motor oil to the kerosene.


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## KC2IXE (Apr 20, 2007)

AAARRRGGGHHHH
Folks - sure you can use WD-40, or Kerosene as cutting fluid, but why not invest a few $$ and buy the real stuff?

One thing that drives me nuts is when folks look for subsitute spindle and way oils. How much does your lathe cost? How much does buying a gallon of the real lube cost? That gallon is going to last YOU a decade. I mean a gallon of way oil is under $20 from MSC, and spindle oil is about the same

A gallon of cutting oil is about $20 - a gallon of Cool Tool is about $40. Or you can go crazy - buy a gallon of soluable oil - again - in the $20 range - but it gets cut like 10-20:1 with water - mix up a quart, get a cheap brush, and flood it on - or better yet, a pump spray bottle

I bought a gallon of each well over a decade ago - and I'm not close to running out


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## scott.cr (Apr 20, 2007)

yclo said:


> This is the other reason that I chose an end mill as drill bits this thick will be even longer, which will give me even less room to work with.



Use screw machine ("stub") drills. The usual hardware store variety drills are too long even for my 9x20 lathe. It's rare to have to drill a hole deeper than you can get with a screw machine drill.

I'm going to risk beating an old horse, but don't be afraid to spend a little extra money when it comes to drills. The cheapies won't last more than one hole through steel, and I'm not even exaggerating a tiny bit. Also, the better drills are ground more accurately, so the tip will be more concentric and you'll get rounder, cleaner holes.


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## kromeke (Apr 20, 2007)

KC2IXE,

Kerosene is a traditional cutting fluid for aluminum. It is "real" for the most part. WD-40 is basically kerosene. Most people have easy access to WD-40. A lot of people already have it in their house. For me, that is one of the few things WD-40 is good for, as I don't consider it a good lubricant. 

While I agree with you on the way and spindle lube, cutting oils are no more "real" than kerosene for cutting and tapping aluminum. Unless one is concerned about biodegradability, or some other specific factors, kerosene is a fine cutting fluid for aluminum. No need to get aggravated. 

yclo,
You can also get stub length drill bits. Commonly known as screw machine drills. As opposed to jobber length.


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## highorder (Apr 20, 2007)

kromeke said:


> KC2IXE,
> 
> Kerosene is a traditional cutting fluid for aluminum. It is "real" for the most part. WD-40 is basically kerosene. Most people have easy access to WD-40. A lot of people already have it in their house. For me, that is one of the few things WD-40 is good for, as I don't consider it a good lubricant.
> 
> While I agree with you on the way and spindle lube, cutting oils are no more "real" than kerosene for cutting and tapping aluminum. Unless one is concerned about biodegradability, or some other specific factors, kerosene is a fine cutting fluid for aluminum. No need to get aggravated.



+1


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## yclo (Apr 23, 2007)

I have used WD-40 as a cutting fluid before, it smokes up real fast when drilling titanium and does not smell pleasant. One thing about handling WD-40 for a long session is that my hands feel really cold afterwards, is that a good thing?

Now the main limitation of my setup is that the tailstock chuck can't hold large diameter drills, even if I used an insert holding boring bar it would have to be able to fit into a 7mm hole.

I haven't been able to locate a larger chuck (that fits), what are my options to use larger drill bits/boring bars?

-YC


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## Anglepoise (Apr 23, 2007)

kromeke said:


> KC2IXE,
> 
> Kerosene is a traditional cutting fluid for aluminum. It is "real" for the most part. WD-40 is basically kerosene. Most people have easy access to WD-40. A lot of people already have it in their house. For me, that is one of the few things WD-40 is good for, as I don't consider it a good lubricant.
> 
> While I agree with you on the way and spindle lube, cutting oils are no more "real" than kerosene for cutting and tapping aluminum. Unless one is concerned about biodegradability, or some other specific factors, kerosene is a fine cutting fluid for aluminum. No need to get aggravated.



+1


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## nekomane (Apr 23, 2007)

yclo said:


> *snip* Now the main limitation of my setup is that the tailstock chuck can't hold large diameter drills, even if I used an insert holding boring bar it would have to be able to fit into a 7mm hole.
> 
> I haven't been able to locate a larger chuck (that fits), what are my options to use larger drill bits/boring bars?
> -YC


These drill bits have a 6.5mm shank and are available up to 13mm.
Saves me a lot of time on my lathe which is close to your's in size.


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## kromeke (Apr 23, 2007)

The WD-40/kerosene advice does not apply well to other metals. WD-40 is actually mostly Stoddard solvent, which isn't much different than kerosene. 

If you are machining a variety of metals or materials, you should follow KC2IXE's advice and get some cutting fluids which are more compatible with several metals. I only wrote what I did because it is sound advice to use kerosene or WD-40 when machining aluminum. I wouldn't consider WD-40 a good cutting fluid to use on anything else. 

Also, I later noticed that your 4 flute mill isn't center cutting. The non-center cutting 4 flute mills aren't suitable for plunge cutting unless there is a pilot hole. If you are going to use an end mill to make a flat bottomed hole, you should drill most of the hole out with a drill, and use the end mill to flatten the bottom. 

You can also regrind drill bits to produce a flat bottom hole, but they are then only good for getting a flat bottom, not for drilling holes where one did not exist before.


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