End Mill Questions

[Bison9]

Hey All,
Ok, a couple noobtacular questions that I absolutely cannot find the answer to anywhere... So I will ask you all. Here goes:

1.) The Dataflute End Mills... So like the ones here: https://heritagecutter.com/dataflute/publicstore/catalog/AFI,117.aspx

I want to get AFIST30375 on that list from the link... Two questions basically here then:

1a. How the crap do I order these (I do know that this one end mill will cost me $100 )???

1b. If you click on the "+" sign by the AFIST30375 model from that link, it gives you two coating choices: 86 and 89... What do these refer to? I sure hope that means one of them is TiN coated (if you can even do that in these carbide deals...)

I also see catalogues upon catalogues of DataFlute Brand End Mills at sites like: http://pdf.directindustry.com/pdf/data-flute-cnc/data-flute-catalog/26515-11320.html

But... I do not know how one goes about actually ordering these... Non of these sites have an "Add to Cart" option... That's probably because only big businesses make purchases of these and not some rumchuck like me... But who really knows...

2.) This question just has been a thorn in my side and people look at me sideways when I ask them, but this is a legit question: So, look at the two end mills from these two links:

http://www.use-enco.com/CGI/INSRIT?PARTPG=INSRAR2&PMAKA=337-5730&PMPXNO=28079080

AND

http://www.use-enco.com/CGI/INSRIT?PARTPG=INSRAR2&PMAKA=337-5565&PMPXNO=28077681

Now, the one in the first link says "Type: Centercutting." The one in the second link says "Type: Regular"... What gives here? Is the second one center cutting as well? If so, why do they not say so...? In my newbness, it is stuff like this that has given me fits in purchasing end mills...

3.) The end mills I listed above in 2.)... Will those give me a decent "finish" on 7075 and 6061 Aluminum?? This is why I am looking into the Dataflute 3 fluted end mills for finishing work...

I mainly am a startup hobbyist machinist finishing AR15 80% lower receivers... Now, before you all laugh, I want a good finish on the pockets on these things... I will not do this project unless I have a nice shiny finish. WIth the $ I have into my setup, $100 for one end mill that will give me the results I want is chump change at this point....

Thanks in advance for any who are willing to help me out. I have already gotten some great information from this site already!!!

 

[Swifty]

I suggest that you email the company and ask for a stockist in your area. As far as centre cutting type cutters go, this means that you will be able to plunge cut down with them like a drill, the regular type will not allow you to do this, you will need to have a hole drilled already to feed the cutter down into, or as you feed along you need to slowly feed the cutter down into the job (know as ramping).

On the Dataflute web page, click on Technical, then Coatings, this will give you information on the best type of coating for the material that you want to machine.

Paul.

 

[Jasonb]

I was talking to a supplier the other day who had just spent a few days in one of the big endmill factories who make for some of the named brands and learn a lot about cutters, he says that for aluminium it is better to use a non coated cutter or a specific coating for aluminium as the smoother surface stops the metal sticking. TiN is not so good

 

[mc_n_g]

A new sharp end mill helps but if your machine is not sturdy enough to handle the cut you are going to run into problems.
CNC or hand crank mill?? CNC will give much better finish if you know how to program for it.
Hand crank machine will leave 'rings' on the bottom. The sides should be ok providing you are cutting at a constant speed and not recutting chips. If you are not clearing the chips do not expect a good finish.
If you don't know the difference between carbide, cobalt and HSS cutting tools don't expect much for performance.
The majority of end mills are centercutting unless stated. I find non-centercutting is not the norm.
If you want a better finish on the bottom I would recommend a small corner radius end mill as it will reduce the 'rings' of a regular square end mill. It will not get rid of them completely. The tips of square end mills are what cause the rings from varying cutting forces. A small radius of "0.015 to 0.030 will help reduce the chance of that and give better surface finish. The only problem is you will not have a square corner at the bottom of the recess. If you expect something to fit extremely tight down to the bottom you will have to contend with the little radius. Sharp corners tend to weaken the part as it causes stress and is a point of failure, which is why many things you see are slight rounded at the base.
http://www.travers.com/4-flute-m-42-8-percent-cobalt-corner-radius-end-mills?Category=UserSearch=radius%20end%20mill||UserSearch=block%20id%20110545%20and%20class%20level3%20id%20297753
If you are cutting aluminum I would recommend a aluminum only cutting end mill. They tend to leave a better finish because the flutes are different.
Cobalt will stay sharper than HSS but cost a little more. Carbide will be your most expensive.
You should not have use a coating on the end mill, unless it is a extremely specialized coating, just don't do it if you don't know it.
I am not quite sure what you expect is a 'nice shiny finish', different things to different folks. Will this come out after being cut looking like a mirror---absolutely not. There are things you can do to help the finish and you need to balance your expectations.

 

[MachineTom]

Bison, I would suggest that before spending $100 or whatever on an end mill. Invest some time in reading information on the subject. This allows you to make a better decision on weather that end mill will help you, or just spend money at a higher rate of speed.

A source that may surprise you is tool catalogs, the MSC catalog has a great description of different types of tools in each section, All about carbide, coatings etc. Enough information to spin your head. I do not know if the online catalog has the same, it might. This is a 5000 page book, so lots of stuff.

A noob guitar player will sound the same on a $100 Harmony as a $30000 Taylor. And you can't mill butter with either one.

Aluminum specific end mills are polished and sharp edged, not honed like a steel cutting em, with a high helix which need high rpm an HP to work. My BP only does 6K rpm which in the AL cutting is slow.

Without knowing what you have for machines, I'll guess like most of us when we start out its a mini or old BP. Neither needs a $100 end mill for AL. YMMV

 

[rtp_burnsville]

I too would not spend $100 on an end mill unless it was a special need that had non-typical requirements. As mentioned, a little more info on your mill, etc would be helpful. I have the best luck with name-brand, non-coated for cutting AL in my Tormach. Avoid the cheap, no-name imports as it's a crapshoot as to what you may get, some work, most don't.

Robert