# Richon Tools order



## Chucketn (Nov 26, 2011)

I received my large order of end mills from Richon Tools today. I purchased 32 cutters in pairs, from 1/16” to 5/8”, 2 and 4 flute, and some metric ball end mills. They came in individual plastic tubes, wrapped in a plastic bag, inside a very tough plastic outer bag.
I opened a few for a look. I was surprised to find several had what appear to be chips in the end cutting edge. At first I thought they were just the profile where the flutes met the cutting edge, but not all of them have this chip. Is this normal? I really don’t want to use them if they are damaged/defective.
Also, to preclude abuse of my new tools, does anyone have or know of a spreadsheet for determining feeds and speeds based on mill cutter diameter? Is there a simple formula that I can put into Excel that would give me a starting RPM, based on cutter diameter and material such as steel, aluminum, or brass?

Chuck in E. TN


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## Tony Wells (Nov 26, 2011)

New end mills should have pristine edges. Mishandling during packaging or shipping could be the cause. Chips in the edge will translate to flaws in the cut surfaces. Unacceptable. I would return for refund.


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## Chucketn (Nov 26, 2011)

I think a picture is in order. I'll go photograph the biggest one and see if the chips show up.

I've e-mailed my dis-satisfaction to Ricoh, we'll see what they say.

Chuck in E. TN


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## Chucketn (Nov 26, 2011)

DaveH,
Thats how some look, but some don't have the little u shaped bit at the end of the spiral where it meets the cutting edge. Is it just a burr left from grinding?

Chuck in E. TN


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## Pacer (Nov 26, 2011)

That is perfectly normal on end mills ... Lemme think of a way to s'plain it...

Thats where the flutes profile emerges at the end, that little cup/trough runs all the way down the flute. I have a dedicated end mill sharpener (Cuttermaster) and in order to 'track' the flutes when rotating the EM across the spinning grinding wheel, that little 'dip' is used as a guide using a needle tipped piece. Its hard to describe!! - am I gonna have to go take a picture??

But that "chip" shown in the pic is normal, so if your EM's are like that, Chuck, then you are good...


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## Chucketn (Nov 26, 2011)

Pacer, some do and some don't have the little u. I'll get some pictures in the morning.

Chuck in E. TN


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## Davo J (Nov 27, 2011)

Hi Chuck,
You have nothing to worry about with your end Mills, that is just the way that style is. I have plenty like it.

As for milling speed
This is a simple way to work out the approx speeds to set your mill at.

This is the cutting Speeds for High Speed Steel (HSS) Cutting Tools.
For carbide, double the speeds in the chart.

Workpiece Material Cutting Speed in surface feet per minute (SFM)
Aluminum & alloys 300
Brass & Bronze 150
Copper 100
Cast Iron, soft 80
Cast Iron, hard 50
Mild Steel 90
Cast Steel 80
Alloy Steel, hard 40
Tool Steel 50
Stainless Steel 60
Titanium 50
Plastics 300-800
Wood 300-500

Measure the diameter of your cutting tool in decimal inches.

Use the following formula to determine the needed RPM for your mill:

SFM from chart x 4, divided by the tool diameter = the RPM needed.

So say for milling mild steel which is 90 SFM in the above chart, and using a 1/2 inch end mill it would be
90 x 4 = 360 divided by 0.5 of an inch = 720 rpm

Hope that helps.
Dave


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## Chucketn (Nov 27, 2011)

After digesting the input here and on a couple of other forums, I have concluded that the Richon end mills are not chipped. There were, however, a few other problems with the order. I had ordered a pair of 10 mm ball Nose end mills and received a pair of straight 10 mm end mills, one extra ½” 2 Flute, and 2 extra 3/8” 4 Flutes and a substituted part # for the 3/16 4 flutes.
I emailed Peter at Richon to apologize for the misunderstanding of the “Chipped” cutting edges and point out the other errors.
Next step is to actually cut something! I will comment here as to cutting quality later, that is if this “Noob” can determine quality!
I also will work on building an Excel based feed and speed Ballpark Calculator that I can enter material and cutter diameter to get a conservative RPM setting.
Thanks to all that commented on this thread.
Chuck in E. TN


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## Pacer (Nov 27, 2011)

Chuck,
Speed & feed can, arguably, be the biggest thorn in a 'newbies' side - too much/to little of one or both ruining the cutter and/or work piece. The problem with using charts - in recent years, especially, is them being set up for production using top end machines and cutters with coolant/lube. We in the home shop do not have those capabilities.

The beginner will almost always run to much speed, and feed - so a good rule to teach your self (and I still follow it) is - if you think you might be going to fast, then you almost certainly ARE, so slow down even more than you think you should... We HSM'ers arent in a rush to get that piece made and slowing down will still get it made and save that brand new EM from turning that ugly brown/black on its end. 

I was really bad about this until I got a mentor and he finally got it in my head... As you get more familiar with using the cutters, you will learn to watch the color of chips, the sound of the cutting action, amount of smoke, etc and will just instinctively know to change it.


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## Chucketn (Dec 3, 2011)

*Was  Richon Tools order, Now Feed and Speed Calculator*

As I said before I am working on a speed and feed "Starting Point" calculator to help me keep from burning up the end mills I just got. I finally got a lookup function to work in excel, so that when I input the material and cutter diameter, it looks up the SFM and calculates the rpm based on the formula given in this thread. 
I know this is "Hobby Machining" and if it sounds good, it's ok. I am just trying to determine a conservative starting point to help me determine the "Sweet Spot" for each cutter.
For example, I am milling 1/4" alumnum plate. I have it vertical in the mill vise. Trying to get first edge trued. I'm using a new 5/8" 4 flute, non center cutting end mill to skim one edge before flipping in the vise and bringing the piece to width. I will then put the piece in the vise horizontally, and use the side of the mill to square the end and bring to length. Also, I will be using aerosol spray WD-40 for lube.
The formula and SFM that DavoJ provided above gives me a rpm of 1920. Did my spreadsheet calculate this correctly? That seems awfull high to me. Also, I will be using aerosol spray WD-40 for lube.
Am I on the right track?

Chuck in E. TN


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## Tony Wells (Dec 3, 2011)

There i another aspect to factor in, and that is chipload per tooth (or edge) At 1920 rpm, with 4 flutes, you are presenting 7680 "cuts" per minute. How fast are you planning on feeding the mill? Aluminum, in it's vanilla form like 6061, anything between 0.005 and 0.015 _per tooth/flute_ should be fine, if you have the HP and rigidity. That makes some fast feeding. ~38 IPM

And depending on depth of cut, you may find a blast of air to just keep the chips clear will be enough. Or a climb cut of 0.005 depth will leave a good finish. Lots of variables.


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## Chucketn (Dec 3, 2011)

I in fact, tried cutting the aluminum plate with the new 5/8" end mill. I was blown away by the finish at 1900 rpm. I still think it's too fast. But can't argue with sucess. 
I squared up the upright and base for the Elmer's #25 I'm building.

Going back to the formula DavoJ posted, what is the constant 4 for?  

Anyone interested in the Excel Calculator I put together with DavoJ's info? Hardest part was getting the Excel function vlookup to work. That takes the metal material name I put in and looks up the SFM value per DavoJ's list. I then plug that and the cutter Dia. into a formula and calculate the RPM.

Actually, I would like folks to evaluate it and see if I need to add features for other 'noobs' like me. Contact me via PM or off list @ chunk07atcomcastdotnet, and I'll send you a copy.

Chuck in E. TN


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## Chucketn (Dec 3, 2011)

Yup x 3!:lmao:

Chuck in E. TN


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## Hawkeye (Dec 3, 2011)

Chuck, just for the record, the constant 4 is derived (according to an old high school shop text) from cutting speed, in feet per minute times 12 (inches per foot) divided by pi (3.14159) times diameter of cutter (in inches). 12/3.14159 is rounded off to 12/3 = 4. So, rpm = CSx4 / D. Close enough if you're changing speeds by shifting belts.


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