# Ok, Rookie Here-- What Am I Doing Wrong?



## Bob V (Apr 30, 2015)

Hi,
I got my old Van Norman Mill about a week ago and have spent time until today cleaning it, changing sump oils, reducing backlash etc.  Basically getting accustomed to the machine and tuning it up per the Manuel.

Today I bit the bullet and made my first cuts.  I clamped down a piece of 1/2 inch steel bar stock (mild steel, I don't know the exact number or hardness).  The Speed and Feed, as best I could tell,  suggested an RPM of about 650 for the 1/2 inch 4 flute HHS end cutter I had in a collett in the spindle.  The feed rate was hard for me to deal with since the machine is currently pure manuel-- no motor feed--so I just tried to "make chips".
My first two cuts across this 4" steel bar were only about 1/16 inch deep and seemed to go fine.
So I cranked the table up for a 1/8 inch depth cut and this went pretty well, but the tool started 'smoking" a bit-- so I used a little foaming cutting oil-- but this didn't seem to stick around long enough to help-- I made it across the 4 inches OK.
I had read that a cutter should be able to cut about half of the cutter diameter-- so I cranked the table up so the cut would be about 1/4 inch deep.  This didn't go very well.  I made it about a half inch into the material and the tool was smoking quite a bit and intermittently was spinning inside the collett--so I stopped.  I tightened the draw bar to incease the collett hold on the tool, but it was already prettty tight- so I didn't think this was the problem.

What am I doing wrong.  Is the tool dull (got it with the mill-- no visible chips under magnification. It's hard to say how fast I'm feeding the table.  I don't want to go to slow (read that this make the tool "rub and overheat") and don't know if I was going to fast.  Why is the tool spinning inside the collett-- I did clean light surface rust out of the collett then coated with WD40-- maybe too slippery?  What's with this "smoking" is that expected if I don't have a high volume cooling system?

Sorry about the long post but I wanted to give as much info as possible.
Thanks in advance,
Bob


----------



## JimDawson (Apr 30, 2015)

I suspect there are a couple of problems here.  I think you are turning a bit fast for the conditions,  maybe about one half that spindle speed to start with.  I suspect that 650 would be the speed you might use with a new end mill under optimal cooling conditions.

It also sounds like the end mill was a bit dull to start with, and was further quickly dulled by over speed.  It sounds like the end mill was not a good fit in the collet or the collet just was not tight.  The collets should be clean and dry as should the end mill shank.  There should also be a minimum of shank sticking out of the collet.  Where possible, I normally have no more than about 1/8 inch of shank showing.

The smoking would be normal.  With a little practice and experience, you will be able to feel and hear when things are just right.


----------



## Bob V (Apr 30, 2015)

JimDawson said:


> I suspect there are a couple of problems here.  I think you are turning a bit fast for the conditions,  maybe about one half that spindle speed to start with.  I suspect that 650 would be thee speed you might use with a new end mill under optimal cooling conditions.
> 
> It also sounds like the end mill was a bit dull to start with, and was further quickly dulled by over speed.  It sounds like the end mill was not a good fit in the collet or the collet just was not tight.  The collets should be clean and dry as should the end mill shank.  There should also be a minimum of shank sticking out of the collet.  Where possible, I normally have no more than about 1/8 inch of shank showing.
> 
> The smoking would be normal.  With a little practice and experience, you will be able to feel and hear when things are just right.



Thank's very much,  Jim, I'll try half the spindle speed tomorrow.  The end mill was well inside the collet-- only about 1/8-1/4" shank showing.  But neither the tool or the collet were dry-- both had fine layer of residual wd40 from cleaning-- I'll clean both with brake cleaner so they grip better- how does that sound?
How do I tell the right speed to manually feed the table? Too slow, it rubs and dulls, too fast it dulls!
--Do you think I ruined the cutter with what I did?


----------



## randyc (Apr 30, 2015)

I'm sure that this is a ridiculous question (it is prompted by the fact that you mentioned tightening up backlash) but you _were_ conventional cutting - as opposed to climb cutting - right ?  As Jim said, the spindle RPM is about right for a _sharp_ 1/2 end mill.

BUT ..... using a small horizontal mill like yours and mine, I wouldn't dream of taking a 1/4 inch DOC in steel with a 1/2 diameter end mill.  If I wanted to take off 1/4 inch of material in a single pass, I'd be setting up a three inch slab mill with the over-arm choked up as close to the work as I could get it and adjusting spindle speed accordingly.

Frankly, I just don't feel comfortable using a horizontal mill for end milling except for fairly light work.  But this is ONLY a personal opinion based on limited experience 

P.S.  When manually feeding the table, a good indication of the correct feed is the sound that the cutter makes.  A sort of "hissing" sound is good.  Make sure that you're clearing the chips from the cut, too, re-cutting chips is not good for finish or for cutter. 

You'll soon learn the ins and outs of your machine with a bit of practice.  BTW, cutters for horizontal mills are still readily available and there are some great buys on eBay.


----------



## Bob V (Apr 30, 2015)

randyc said:


> I'm sure that this is a ridiculous question (it is prompted by the fact that you mentioned tightening up backlash) but you _were_ conventional cutting - as opposed to climb cutting - right ?  As Jim said, the spindle RPM is about right for a _sharp_ 1/2 end mill.
> 
> BUT ..... using a small horizontal mill like yours and mine, I wouldn't dream of taking a 1/4 inch DOC in steel with a 1/2 diameter end mill.  If I wanted to take off 1/4 inch of material in a single pass, I'd be setting up a three inch slab mill with the over-arm choked up as close to the work as I could get it and adjusting spindle speed accordingly.
> 
> Frankly, I just don't feel comfortable using a horizontal mill for end milling except for fairly light work.  But this is ONLY a personal opinion based on limited experience


Randy, 
Not a ridiculous question--but I managed to remember not to climb mill.  My machine is a vertical mill that can be turned horizontal by rotating the head.
I don't think the Van Norman 16 is a "small mill" -- but maybe that's just my ignorance! --it's 2500 pounds of steel-- is that "small"?


----------



## randyc (Apr 30, 2015)

Vanderlinde said:


> Randy,
> Not a ridiculous question--but I managed to remember not to climb mill.  My machine is a vertical mill that can be turned horizontal by rotating the head.
> I don't think the Van Norman 16 is a "small mill" -- but maybe that's just my ignorance! --it's 2500 pounds of steel-- is that "small"?



Yep, for horizontal mills a ton of weight is a fairly small machine - that's roughly the same size as my Lietz (universal horizontal with detachable vertical head).  Sorry about the misunderstanding regarding head orientation but that doesn't change my opinion that a 1/4 DOC in steel with a 1/2 end mill is bad ju-ju, even with very fine feed and coolant.


----------



## JimDawson (Apr 30, 2015)

I really don't know how to put the proper hand feed rate into words, it's a feel.  If it's cutting slivers off, it's probably OK.

Cleaning the collet and cutter with brake clean would be good.

A new, high quality, sharp cutter will have a razor edge and will cut your finger.  Cutters will work long past razor sharp, but there is some point that they quit cutting and start rubbing, a dull knife will sort of still cut.  Normally you will see a large burr on the edge of the cut when they are pretty dull, and the feed effort will increase dramatically.  If the machine is stable enough and you have enough power you can take a cut the full diameter of the end mill, but more normal is around 0.4 diameter to keep the end mill from pulling into the work.


----------



## Bob V (Apr 30, 2015)

randyc said:


> Yep, for horizontal mills a ton of weight is a fairly small machine - that's roughly the same size as my Lietz (universal horizontal with detachable vertical head).  Sorry about the misunderstanding regarding head orientation but that doesn't change my opinion that a 1/4 DOC in steel with a 1/2 end mill is bad ju-ju, even with very fine feed and coolant.


Thanks again, Randy,
So: slower spindle speed (about 300) , DRY tool and inside of collet, and maybe cuts 1/8" deep?
Do you guys think I already ruined the tool?


----------



## Bob V (Apr 30, 2015)

JimDawson said:


> I really don't know how to put the proper hand feed rate into words, it's a feel.  If it's cutting slivers off, it's probably OK.
> 
> Cleaning the collet and cutter with brake clean would be good.
> 
> A new, high quality, sharp cutter will have a razor edge and will cut your finger.  Cutters will work long past razor sharp, but there is some point that they quit cutting and start rubbing, a dull knife will sort of still cut.  Normally you will see a large burr on the edge of the cut when they are pretty dull, and the feed effort will increase dramatically.  If the machine is stable enough and you have enough power you can take a cut the full diameter of the end mill, but more normal is around 0.4 diameter to keep the end mill from pulling into the work.


Ok, thanks again.  -So if I want to do a plunge into steel with this machine-- should I start with a 2 fluke, maybe 1/4 inch tool?


----------



## randyc (Apr 30, 2015)

Vanderlinde said:


> Thanks again, Randy,
> So: slower spindle speed (about 300) , DRY tool and inside of collet, and maybe cuts 1/8" deep?
> Do you guys think I already ruined the tool?



I'd defer to Jim for just about all of this but I'd speculate that your end mill is <ahem> not optimally configured at this point   Dry cutting is OK if you have the means of clearing chips and keeping the cutter cool.  This is my method - maybe not the best but seems to work.

It's just a small air valve and air wand attached to a magnetic base.  I adjust the little air valve to obtain a trickle of shop air - just enough to clear the chips from the cutter.  It's not good to blow chips all over the place, they tend to end up in places that later cause problems, LOL.  The air obviously cools the cutter as well as clearing chips.

Not visible from this angle but a similar arrangement on the far side provides coolant spray through a wand directed toward the cutter from a reservoir and coolant pump.  I rarely use it though - it's a mess and the coolant tends to get stinky after sitting in the reservoir for a few months.




P.S.  Jim mentioned the resistance to feed increasing dramatically with a dull cutter.  That's something that needs to be monitored, even when using power table feed.  My personal practice is to introduce the cutter into the work by hand, then feed it by hand for a bit before engaging power feed.

I believe that it's also good practice to disengage the power feed occasionally and check cutting resistance by moving the table by hand.  You'll learn by doing ... the "feel" and sound of the cutting process will provide feedback that tells you how the work is progressing


----------



## JimDawson (Apr 30, 2015)

If you are plunging for a slot for instance, then a 2 flute, center cutting end mill would be my choice.  The real key here is center cutting.  For slotting I would always choose a 2 flute they tend to walk sideways less.  Where possible I will first drill a hole for plunging, as you suggest 1/4 inch is good.

PS:  +1 What RandyC said above.


----------



## Bob V (Apr 30, 2015)

randyc said:


> I'd defer to Jim for just about all of this but I'd speculate that your end mill is <ahem> not optimally configured at this point   Dry cutting is OK if you have the means of clearing chips and keeping the cutter cool.  This is my method - maybe not the best but seems to work.
> 
> It's just a small air valve and air wand attached to a magnetic base.  I adjust the little air valve to obtain a trickle of shop air - just enough to clear the chips from the cutter.  It's not good to blow chips all over the place, they tend to end up in places that later cause problems, LOL.  The air obviously cools the cutter as well as clearing chips.
> 
> ...


----------



## Bob V (Apr 30, 2015)

Thanks, Randy.  I did notice  piles of chips developing around the mill. I had to stop it to brush them away.. My machine has a sump for coolant and motor to pump it, then it drains thru a hose back into a sump in the base--maybe I should hook this up--will have to wire it to the phase converter-- another project!


----------



## chips&more (Apr 30, 2015)

If you started with an unknown piece of steel you should have set the RPM at the “very” low end. And if using hand feed, listen for problems and look for the not wanted blue chips. And take small/light cuts and use cutting oil until you get a feel for the unknown material and your machine…Good Luck, Dave.


----------



## Bob V (Apr 30, 2015)

Thanks, Dave.  More great advice for a new guy. This forum is great!


----------



## randyc (Apr 30, 2015)

Vanderlinde said:


> Thanks, Randy.  I did notice  piles of chips developing around the mill. I had to stop it to brush them away.. My machine has a sump for coolant and motor to pump it, then it drains thru a hose back into a sump in the base--maybe I should hook this up--will have to wire it to the phase converter-- another project!



You could do that but for most hobby machinists, an acid brush and a little container with some cutting oil (sulphur-based pipe threading oil) from your hardware store works fine.  Much less mess ... the brush can be applied to the exact area that needs cutting fluid and chip clearing.


----------



## Bob V (Apr 30, 2015)

randyc said:


> You could do that but for most hobby machinists, an acid brush and a little container with some cutting oil (sulphur-based pipe threading oil) from your hardware store works fine.  Much less mess ... the brush can be applied to the exact area that needs cutting fluid and chip clearing.


Thanks Randy. Will go that route first for sure.  The you-tube videos I've seen of the coolant flowing does look a mess!  I have some "Magic" Cutting oil I use for drilling--maybe that would work for the mill too.


----------



## Bob V (Apr 30, 2015)

randyc said:


> I'd defer to Jim for just about all of this but I'd speculate that your end mill is <ahem> not optimally configured at this point   Dry cutting is OK if you have the means of clearing chips and keeping the cutter cool.  This is my method - maybe not the best but seems to work.
> 
> It's just a small air valve and air wand attached to a magnetic base.  I adjust the little air valve to obtain a trickle of shop air - just enough to clear the chips from the cutter.  It's not good to blow chips all over the place, they tend to end up in places that later cause problems, LOL.  The air obviously cools the cutter as well as clearing chips.
> 
> ...



Randy, is that "ball and socket" thing with the black base the magnet?  Looks like a great idea. I have air 5 feet from my mill. Do  you remember where you got that magnet thing?  I recognize most of the other pieces of the system-- but any parts, specs would be appreciated.


----------



## T Bredehoft (May 1, 2015)

Basic rule of thumb,  High Speed Steel shouldn't be run faster than 90 surface feet a minute. Sure you can get away with 120, if you're cutting Ledloy, or brass, but for steel, 90 surface (of the cutter) feet per minute is good. A half inch tool then is turning 180 RPM.


----------



## Bob V (May 1, 2015)

T Bredehoft said:


> Basic rule of thumb, * High Speed Steel shouldn't be run faster than 90 surface feet a minute*. Sure you can get away with 120, if you're cutting Ledloy, or brass, but for steel, 90 surface (of the cutter) feet per minute is good. A half inch tool then is turning 180 RPM.


Thanks, Tom.
I'll try running the 1/2 inch tool at 180 RPM.  
I certainly believe you guys-- you have the hands on experience-- I obviously don't.

 I used an online Speed and Feed Calculator  at "Daycounter Engineering Services" web site, and plugged in the cutter diameter (.0.5"), and a SFM of 90, and it gives me a spindle speed of *687 RPM*.

 Also using the formula: 
RPM = (Cutting Speed x 4)/Diameter
RPM=90*4/.5=*720 RPM
*
Question:  these tables/calculators give speed rates roughly  4 times faster than what is being recommended by you and others.--Can you please tell me why there is such a difference between the RPM's recommended by the tables and the 180 RPM you recommend?

Once again-- having tried the 600+ RPM yesterday with lots of problems-- I certainly appreciate your help and am going to try all your recommendations today.
Thanks!
Bob


----------



## JimDawson (May 1, 2015)

Your calculated spindle speed and formula are correct.  BUT, those numbers are for a new, sharp end mill, cutting under optimal conditions in a production environment for maximum metal removal rate.  The home shop rarely has optimal conditions, so we make allowances.

Normally half of those speeds is a good starting point.  The worst enemy of an end mill is heat.  Slower speeds = less heat.

A air nozzle or a mist coolant system would be very helpful.  I use one or the other depending on what I am doing.


----------



## T Bredehoft (May 1, 2015)

Surface feet is diameter x pi (3.14) for any cutter. .5 x 3.14 is 1.57 inches.  That is 13% of a foot so 7.64 revolutions is one foot. to go 90 feet it must go 90 times 7.64 or 678 ROM..  My 180 is off by a factor of 3.82 or nearly 4.

Your chart is right, but here's the rub.  90 is for the mildest steel. I work in 4140 because I want a tough steel to  hold my lathe tools where I want them. It's cutting speed is nearer 26, you may be working in something more difficult to work than 1018, common cold rolled steel.


----------



## randyc (May 1, 2015)

Vanderlinde said:


> Randy, is that "ball and socket" thing with the black base the magnet?  Looks like a great idea. I have air 5 feet from my mill. Do  you remember where you got that magnet thing?  I recognize most of the other pieces of the system-- but any parts, specs would be appreciated.



Yes, you've correctly identified the little magnetic air valve gizmo.  I _think _that it came from Harbor Freight but if it's no longer available, you can rig up something with fittings from the hardware store ...


----------



## randyc (May 1, 2015)

T Bredehoft said:


> Basic rule of thumb,  High Speed Steel shouldn't be run faster than 90 surface feet a minute. Sure you can get away with 120, if you're cutting Ledloy, or brass, but for steel, 90 surface (of the cutter) feet per minute is good. A half inch tool then is turning 180 RPM.



Tom, I get 688 RPM from the following:  (SFPM x 12) / (Pi x cutter diameter).  Are you sure that you're not multiplying by the cutter diameter instead of dividing ?  Just a thought 

Edited:  Never mind, I didn't look down far enough to where you corrected it, Sorry Tom


----------



## randyc (May 1, 2015)

JimDawson said:


> .....BUT, those numbers are for a new, sharp end mill, cutting under optimal conditions in a production environment for maximum metal removal rate...



Just to add one more qualification to Jim's comments:  cutting speeds are _generally_ based on some nominal time _between sharpenings_.  IIRC, this figure is generally around 2 hours.

So as an example, starting with a new cutter, you can probably run at 90 SFPM in steel for about 2 hours before the tool dulls to the point that it needs either replacement or sharpening.

Using half the RPM from the tables will likely increase tool life by at least a factor of three, all other things being equal


----------



## Bob V (May 2, 2015)

Randy, Jim, and everyone else on this thread:
-Thought I would give you a brief update after all your great advise-

Yesterday:  I ran the .5 inch cutter in the same steel (Tom, it may well be cold rolled stock!) at 180 RPM and a manual feed rate (don't know exactly what this was but "slow"), and squirted the cutter with cutting oil whenever it looked "dry". I had cleaned out the collet with  brake cleaner (and the mill shank), and installed it almost to the flutes.
--It went great!  I ended up cutting the side of the piece about .25 inch deep with about half the cutter diameter.  - No hard feeding, no cutter spinning in collet, minimal "smoke".

Without your advise I would still be scratching my head about all this.

--Much appreciated!
Bob


----------



## T Bredehoft (May 2, 2015)

That's what we'ere here for, Bob, to keep the world's wheels turning.


----------



## Bob V (May 2, 2015)

randyc said:


> Yes, you've correctly identified the little magnetic air valve gizmo.  I _think _that it came from Harbor Freight but if it's no longer available, you can rig up something with fittings from the hardware store ...


Randy, I will rig up an air cooler/chip clearer. It will look pretty much like yours-- why reinvent the wheel with generous folks like you out there!


----------



## benmychree (May 3, 2015)

Vanderlinde said:


> Thanks, Randy.  I did notice  piles of chips developing around the mill. I had to stop it to brush them away.. My machine has a sump for coolant and motor to pump it, then it drains thru a hose back into a sump in the base--maybe I should hook this up--will have to wire it to the phase converter-- another project!


From what I have read so far in this thread, I think your biggest problem is the lack of coolant, and yes. by all means hook it up and use it; steel should never be milled dry, especially for removing a significant amount of stock.  With lighter work, cutting oil and a brush can be used, but with care not to overspeed or feed or depth of cut; in hand feeding, your hand on the crank and your hearing will tell you when you are pushing things too hard.  The speed of 650 rpm should have been fine with coolant being used, as it is only about 85 fpm cutting speed; up to about 100 fpm can be used with steel with coolant. As others have suggested, sharpness is also a big issue, indeed, it should be sharp enough to cut your finger; if the cutter is dull, high heat is generated, further dulling it until failure is the result.  A suggestion for guidelines on feed and speed can be derived from handbooks, or more simply from a slide rule speed and feed calculator that used to be given away by tool manufacturers, made of cardboard.  They integrate all the factors relating to cutting speeds, feeds, tool material and material hardness, available horsepower, etc., but there is one scale devoted to tool diameter, cutting speed and rpm only that would likely serve your needs.  Mine was made by Kennametal.  You could likely find one on E Bay.


----------



## janvanruth (May 3, 2015)

nothing wrong with your arithmatic
tables were made for industry, tend to give numbers for maximum toollife in respect to maximum amount of chips, a matter of making the most  money  out of a cutter, and will presume flood coulant and auto feed.
taking it easy on the feeds and speeds with no coulant and hand-crancking will not make as much money out of a cutter but will make the cutter hold on for much longer


----------



## Bob V (May 3, 2015)

Thanks again to everyone- great forum!


----------



## barrydc1 (May 4, 2015)

Where did you get the SFM of 90.  That seems a bit high for most steel except the most mild.  I would go with 50 as and SFM and same formula, so your RPM should be 400, but as others have said, if you are side milling it often needs to be much less in my experience, but that may the the approach to the work on the tool (see this link: http://www.abtoolsinc.com/pdf/AB_Tools_Inc_Catalog_2012.pdf ) They have some opinions on this, but pretty complex if you're new to this.  If you are slotting or faceing, then definitely go with the calculated RPM.  Smoke is okay unless your chips are turning blue or purple.  Chatter and squeal are not okay and indicate too high a feed rate (not too high RPM).  You'll eventually break a cutter if you continue to force a vertical endmill. I don't to any horizontal milling, so if none of this pertains, good luck!  Find a good chart online or in Machinery Handbook for the SFM of all the materials you're cutting, and apply that formula until you get a really good feel for it all.


----------



## jaded13640 (May 5, 2015)

All I can do is echo what others have already said. What a machine or it's cutter is "supposed" to be able to handle and what it can actually handle are two different things. On a light machine, especially an older, well used machine, you really have to go by feel. Start out with about half the speed that's recommended and feed it based on what it will "handle". Gradually pick up the pace on feed and the same with feed until you get a feel for what your machine will handle. Your situation may be a dull cutter or any number of minor wear issues with your machine. Once you get a feel for your machine you'll just know what to set it at without calculating the "correct" speed and feed.

Good luck and enjoy your new machine.

Wayne


----------



## jaded13640 (May 5, 2015)

All I can do is echo what others have already said. What a machine or it's cutter is "supposed" to be able to handle and what it can actually handle are two different things. On a light machine, especially an older, well used machine, you really have to go by feel. Start out with about half the speed that's recommended and feed it based on what it will "handle". Gradually pick up the pace on feed and the same with feed until you get a feel for what your machine will handle. Your situation may be a dull cutter or any number of minor wear issues with your machine. Once you get a feel for your machine you'll just know what to set it at without calculating the "correct" speed and feed.

Good luck and enjoy your new machine.

Wayne


----------



## Bob V (May 5, 2015)

Thanks again!  I think I need to just make some chips and get more experience with the machine, but I would have been really puzzled about the speed issue if you guys hadn't helped--much appreciated.


----------



## Ropetangler (May 5, 2015)

T Bredehoft said:


> Basic rule of thumb,  High Speed Steel shouldn't be run faster than 90 surface feet a minute. Sure you can get away with 120, if you're cutting Ledloy, or brass, but for steel, 90 surface (of the cutter) feet per minute is good. A half inch tool then is turning 180 RPM.


Sorry buddy but your maths don't add up here. By my calculations 90 surface feet per minute is 687 rpm for a 1/2" diameter end mill, I'm not sure where you get 180 rpm from, but Vanderlinde was pretty well on the mark with his spindle speed. I would also agree with him that his Van Norman is a pretty substantial mill by home shop standards, much stiffer than a Bridgeport if properly adjusted, and not like some of the more low end Asian machines in regard to machine rigidity.
I'm not a machinist , just a wanna be, but my suggestion would be to ask a local machinist if you know any to come to your place and look over your setup. You may have some part out of adjustment, a loose gib or similar, and you don't have the experience yet, to know if your cutters are sharp or not, so perhaps you could purchase a new one and make sure that you haven't toasted your collet, by spinning your old cutter. They definitely should be run dry, but scrupulously clean, check for any burs in the collet or on any cutter shanks.
Apologies for pointing out the mistake in the calculations, - I've just realised that there is a second page to this thread, and others have pointed out the mistake already. I still stand by my comments on the Van Norman however, if that machine is adjusted up correctly, even if well worn, I would expect it to be far more rigid than the usual Asian machines found in home shops, but in view of the lack of experience of  Vanderlinde, it may well need to be tweeked up in some areas to realise its full potential. Good luck, and you have already found plenty of helpful blokes on this forum to help you get started.
Rob


----------



## scrdmgl (May 5, 2015)

Vanderlinde said:


> Hi,
> I got my old Van Norman Mill about a week ago and have spent time until today cleaning it, changing sump oils, reducing backlash etc.  Basically getting accustomed to the machine and tuning it up per the Manuel.
> 
> Today I bit the bullet and made my first cuts.  I clamped down a piece of 1/2 inch steel bar stock (mild steel, I don't know the exact number or hardness).  The Speed and Feed, as best I could tell,  suggested an RPM of about 650 for the 1/2 inch 4 flute HHS end cutter I had in a collett in the spindle.  The feed rate was hard for me to deal with since the machine is currently pure manuel-- no motor feed--so I just tried to "make chips".
> ...


Hi Bob:
Congratulations on your new mill. If you have a chance send us a picture of your mill because I'm sure that most of us would love to see it.

Regards

Jorge


----------



## larryr (May 5, 2015)

Vanderlinde said:


> Thanks, Tom.
> I'll try running the 1/2 inch tool at 180 RPM.
> I certainly believe you guys-- you have the hands on experience-- I obviously don't.
> 
> ...





scrdmgl said:


> Hi Bob:
> Congratulations on your new mill. If you have a chance send us a picture of your mill because I'm sure that most of us would love to see it.
> 
> Regards
> ...


jorge       if you want a quick ballpark spindle speed calculator  multiply 4x the sfpm and divide by the cutter diameter. for a 1/2 endmill at 100 sfpm this works out  to 800rpm. this would be max speed. i have a van norman 12 and i regularly run 1/2 endmills at about 600 rpm with no trouble. you need to slow down and get to know your machine. the depth of cuts you were taking sound excessive to me. i usually start with .050 depth of cut and work my way up from there. use your hand feed and you will be able to feel the cut. you are looking for straw colored chips and a fairly light resistance on the feed handle. i use some brush on cutting oil. the coolant system tends to make a mess and you need to maintain it to prevent bacteria growth and the stink. you mentioned your cutter slipping in the collet. van norman collets use i peculiar looking key in the spindle to locate the collet. if this is missing it could allow the cutter to spin. i have also seen some collets that wouldn't draw up properly on the key causing the same problem. bottom line is make sure you have a sharp cutter and start slow with your feeds and speeds. you can only feed as fast as your tool can cut so if your spindle speed is low the feed has to slow down . van norman mills are fun machines, good luck. check out utube , there are a lot of good machine shop videos to watch.


----------



## Bob V (May 5, 2015)

Thanks Ropetangler (what gave you that handle!), T Bredehoft, larryr, and everyone else.


Ropetangler said:


> Sorry buddy but your maths don't add up here. By my calculations 90 surface feet per minute is 687 rpm for a 1/2" diameter end mill, I'm not sure where you get 180 rpm from, but Vanderlinde was pretty well on the mark with his spindle speed. I would also agree with him that his Van Norman is a pretty substantial mill by home shop standards, much stiffer than a Bridgeport if properly adjusted, and not like some of the more low end Asian machines in regard to machine rigidity.
> I'm not a machinist , just a wanna be, but my suggestion would be to ask a local machinist if you know any to come to your place and look over your setup. You may have some part out of adjustment, a loose gib or similar, and you don't have the experience yet, to know if your cutters are sharp or not, so perhaps you could purchase a new one and make sure that you haven't toasted your collet, by spinning your old cutter. They definitely should be run dry, but scrupulously clean, check for any burs in the collet or on any cutter shanks.
> Apologies for pointing out the mistake in the calculations, - I've just realised that there is a second page to this thread, and others have pointed out the mistake already. I still stand by my comments on the Van Norman however, if that machine is adjusted up correctly, even if well worn, I would expect it to be far more rigid than the usual Asian machines found in home shops, but in view of the lack of experience of  Vanderlinde, it may well need to be tweeked up in some areas to realise its full potential. Good luck, and you have already found plenty of helpful blokes on this forum to help you get started.
> Rob



Thanks, Ropetangler (how did you get that handle!).   Based on all the help on this forum, I think I was doing several things wrong: 1) I don't know whether the 1/2 inch cutter I was using was sharp or not.-- I have bought a 1/4" center cutting end mill from Niagra-- haven't had a chance to try this out, but it at least eliminates that variable-- and I'll run it slowly at first so I don't ruin it. 2)  The cutter spinning in the collet: I only hand tightened the drawbar and there was some WD40 on the outside of the collet-- I think both these things allowed the cutter to spin in the collet under load. Also almost all the collets I received with the machine (about 15+ of them) have internal rust and some have burrs-- I am trying to figure out the best way to clean up the inside of these collets to improve runout at the tool. 3) The collet slots -- no problem with the 1/2" collet here, but many of the collets have damaged external key slots-- I plan to clean these up with a dremmel, since guys on this forum tell me that the spring steel collets really can't be remachined with a slot cutter. 4) -Probably the worst thing I did: after about a 10-20 thou cut-- I went straight to a .25" cut-- with all the problems I mentioned in my first post. I went to the .25" cut because I had seen a guy on youtube who said you can cut to a depth=1/2 of the tool diameter-- but as guys here have pointed out-- that's probably under ideal circumstances=coolant, sharp cutter etc.
      Right now, the piece of help I could use the most is how to best clean up and deburr the  insides of the collets and toolholders I got with the machine without increasing tool runout.  I got about 6-7 toolholders (don't even know what tools most of them hold!) and the collets need the insides cleaned.  I mentioned that an arbor I bought has a mirror finish-- and (again on this forum) I've learned there should be a mirror finish on the inside of some of the toolholder-- how can I restore this?  I bought some fine emery cloth and cleaned up one toolholder with a M2 taper so I could attach my Jacobs chuck-- and the emery cloth reduced runout of the chuck from 35 thou to 2 thou-- but obviously no mirror finish! 
--Sorry about running on here--
Bob


----------



## Bob V (May 5, 2015)

larryr said:


> jorge       if you want a quick ballpark spindle speed calculator  multiply 4x the sfpm and divide by the cutter diameter. for a 1/2 endmill at 100 sfpm this works out  to 800rpm. this would be max speed. i have a van norman 12 and i regularly run 1/2 endmills at about 600 rpm with no trouble. you need to slow down and get to know your machine. the depth of cuts you were taking sound excessive to me. i usually start with .050 depth of cut and work my way up from there. use your hand feed and you will be able to feel the cut. you are looking for straw colored chips and a fairly light resistance on the feed handle. i use some brush on cutting oil. the coolant system tends to make a mess and you need to maintain it to prevent bacteria growth and the stink. you mentioned your cutter slipping in the collet. van norman collets use i peculiar looking key in the spindle to locate the collet. if this is missing it could allow the cutter to spin. i have also seen some collets that wouldn't draw up properly on the key causing the same problem. bottom line is make sure you have a sharp cutter and start slow with your feeds and speeds. you can only feed as fast as your tool can cut so if your spindle speed is low the feed has to slow down . van norman mills are fun machines, good luck. check out utube , there are a lot of good machine shop videos to watch.



Hi Larry, thanks for your comments.
I figured out the key/slot situation, and I think I have that under control.  I'm still working on excessive runout caused by rough internal collets, and internal tool holders- need a way to clean this up.
Speed and feed: I'm going to try starting slow, with a new Niagra cutter and get some experience!  (after I get my crops planted).
Bob


----------



## randyc (May 5, 2015)

Ropetangler said:


> Sorry buddy but your maths don't add up here. By my calculations 90 surface feet per minute is 687 rpm for a 1/2" diameter end mill, I'm not sure where you get 180 rpm from...



Rob, you didn't read the following posts where Tom corrected his figure, see #22.  No offense - I'm not directing this specifically at you - but it seems a common practice for people to respond to a perceived error without reading the posts that follow


----------



## JimDawson (May 5, 2015)

Vanderlinde said:


> I figured out the key/slot situation, and I think I have that under control. I'm still working on excessive runout caused by rough internal collets, and internal tool holders- need a way to clean this up.



 A small hone?
.
.


----------



## markknx (May 6, 2015)

Bob,
I have nowhere near the experience these guys do, but I have read and been told 1st. these charts are to get you close, 2nd they are for production work, were labor to tool costs come into play, 3rd all condition need to be right, speed, feed, sharp tool, known materials.... I think 180 seems slow for a 1/2 end mill, but hey you can try.

Now where I can help you a little bit more is I started like you no training and these guys to help me, and a manual machine. I would bang my head over speed and feed charts, ask questions and get all sorts of answers. as far as feed goes unless someone can see you milling it is hard to say to fast or slow. hard for me to come to grips there. But once I got a little feel and understanding it got better quick.

If you get the RPMs right or a little slow (I have seen nothing to tell me lower RPMs are all that bad) higher RPMs will dull bits fast so better a little slow you can always go faster if things are going well. The feed will be easier to feel the cutter will make chips with little effort on the hand wheel. if the chips are stringy (I mean thin slivers) crank a little faster. if they are coming off blue slow down a little. a nice straw color is good. Watch some you tube videos of mills cutting and pay attention to the chips.

+1 on all of what Jim and Randy have told you. the guys are pros so try what they said. and good luck.

Hey glad you like it here at HM Oh my bet is the end mill is toast, but don't pitch it. and get used to killing them as you learn. I would buy cheaper ones till you get a handle on speed and feed.
Mark


----------



## Bob V (May 6, 2015)

Thanks, Mark,
I already know a bit more than I did -- just from this one thread!
Best regards,
Bob


----------



## Pops (May 7, 2015)

I started machining when I was 16. Had several classes in high school on machining and also some college training. During college I got a part time job in a machine shop. I had a wonderful tool maker boss. He saw I was very interested to learn and really took me under his wing and taught me a lot. One of the things he impressed is that while most of the charts out there on speeds and feeds are just basic and will get you "close" to what the feeds and speeds actually should be. There are so many variables,  material, condition of cutter,  etc. that it would take many long charts to solve every problem. He said it is mainly time and experience that will do the job. I have been doing machine work for over 50 years and very seldom use a chart. It comes down to feel, sound and experience to get machining right. If you get everything "right" your tooling will last you a long time. 
I use a good grade of cutting oil very sparingly applied with an acid brush. They are sold in a package of about 20, I believe, from harbor freight. While applying oil you can also brush off the chips. I never use air; makes to much of a mess!

Happy machining,
Barry


Sent from my iPad using Tapatalk


----------



## brino (May 7, 2015)

Vanderlinde said:


> I bought some fine emery cloth and cleaned up one toolholder with a M2 taper so I could attach my Jacobs chuck-- and the emery cloth reduced runout of the chuck from 35 thou to 2 thou-- but obviously no mirror finish!



Thanks for publishing those numbers Bob.
Wow, that's quite a change. I never thought the before and after could be so different from a mild clean-up with emery.
I may have to check a few of my own.......
-brino


----------



## Bob V (May 8, 2015)

Pops said:


> I started machining when I was 16. Had several classes in high school on machining and also some college training. During college I got a part time job in a machine shop. I had a wonderful tool maker boss. He saw I was very interested to learn and really took me under his wing and taught me a lot. One of the things he impressed is that while most of the charts out there on speeds and feeds are just basic and will get you "close" to what the feeds and speeds actually should be. There are so many variables,  material, condition of cutter,  etc. that it would take many long charts to solve every problem. He said it is mainly time and experience that will do the job. I have been doing machine work for over 50 years and very seldom use a chart. It comes down to feel, sound and experience to get machining right. If you get everything "right" your tooling will last you a long time.
> I use a good grade of cutting oil very sparingly applied with an acid brush. They are sold in a package of about 20, I believe, from harbor freight. While applying oil you can also brush off the chips. I never use air; makes to much of a mess!
> 
> Happy machining,
> ...


Thanks, Barry, nothing quite like 50 years of experience.
Bob


----------



## Bob V (May 8, 2015)

brino said:


> Thanks for publishing those numbers Bob.
> Wow, that's quite a change. I never thought the before and after could be so different from a mild clean-up with emery.
> I may have to check a few of my own.......
> -brino


Hi brino,
Yes, the change from 35 thou (I could see the chuck wobble) to two thou surprised me too.  I used "fine" emery paper-- but I don't know what grit it was-- certainly didn't leave a shiny finish.


----------

