[ad64075]

How is it for tramp oil rejection?

Excellent. Tramp oil rests well atop the E206 coolant and is removed well by belt and disc skimmers; of course most effectively with a coalescer. I have experimented with using a centrifuge to extract the oils in the coolant that traditional skimming methods have missed, but to my delight, the amounts of oil were negligible. What does this all mean? Tramp oil does not "infuse" with the coolant mixture when using E206 to any harmful degree.

[Veracity]

Im using a HAAS TM-2 that does not use oil but grease for the ways. Using TRIM C270 but find that 1% less on concentration leaves rust spots on the table, and 1% over recommended concentration, leaves greenish residue underneath vise/chuck. But not on the surface of the table where there is no vice mounted. Tried to clean table and vice with bleach, solvents, oil, WD40, with all the same results... So i am in the hunt for a more reliable coolant.

[brokencarbide]

First off, blaser is an ok coolant. But they use it at the trade shows cause its free, just like distributers will use it in the showrooms cause its free. It will go bad, and will leave sticky crap everywhere, just like every other coolant I've seen. I've used more than most I'm sure, we always got free samples working for distributors. blaser will foam at moderate pressures, and really foam at high pressures, until it gets a couple weeks old. Trim makes some good products, however the perfume they put in the trim makes me sick. Everyone has a magic coolant, just look at there literature. I had switched to a company called gc lubricants for the showroom. Machines sat and sat there, it held up great, didn't stink out the office, and didn't stain the machines. Down side it was not a good coolant for stainless or gummy materials. My personal belief with coolants is it depends on who will support you if you have issues. If company a's coolant is that much better than company b, company a should put up or shut up. Ask where your free tank full is to try it. Also keep in mind I might not be allergic or get dermatitis from coolant a, but you might.
My order of preference for sump life only is

Gc lubricant, synthetic
Hangstefer
Blaser
Trim (not trim sol!)
Valcool

I guess i didn't realize they give the stuff away, but it makes sense for them i suppose to get the product out there, it sure isn't cheap, I think we're up to $1300 per drum now, but we still all agree in the shop it's been the best thing we've used, and we've tried alot years past. We do see foaming issues when we run high pressure thru the carbide drills, no doubt about it, but we typically throw a cap full of their defoamer stuff in the machine and it's good to go. Hangstefers we threw out of the lathes because they smelled like an open gear case, our wives were all happy when we got rid of that stuff. as far as everybody cheering on E206, we tossed that out of the 3 mills that hadn't yet switched to Hangstefers because the Blaser smoked up on the tapping tool life so much, E206 wasn't even close. The rep asked us to stop in the middle of a production lot of some 1541 material, and the only thing we changed was the coolant, and our tap life went from 75-80 pcs, to 125 pcs... no question, no arguement, the coolant alone did that. Who know's things could change, just like carbide grades, but for now, I'm sold on Blaser.

[RCaffin]

Tried a variety of coolants etc on aluminium and plastics. None of them were satisfactory.

What I noticed was that the real problem was that the cutter got clogged up and the build-up of swarf made the cutter red hot. And then it broke. Coolants did not solve that. Mind you, that's milling, not tapping.

Switched to a hard air blast for milling and haven't looked back. It cools the cutter and the object for sure, but far more importantly it keeps the cutter 100% clear of chips. No chips, no build-up, no problems.

My 2c.

cheers

[RomanLini]

Hi RCaffin, can you share details of your air pump type or any more info? Do you cool the air?

[RCaffin]

Hi RCaffin, can you share details of your air pump type or any more info? Do you cool the air?

Nothing special!

One workshop air compressor - they are pretty cheap these days.
One air hose to a connector and a (manual) valve on the body of the machine.
A length of that blue very bendy coolant tube which comes in segments, mounted inside.
A small nozzle on the end to restrict the air flow a bit more, to get speed.

The 'nozzle' is just a short length of thick-wall silicone hose stuffed into the stock orange nozzle you get with those bendy hoses. I found that the silicone hose has some real advantages: hot chips don't hurt it, and if it bumps against something the silicone hose just flexes.

Yeah - I shut the cover door when the air is running. :-)

Cheers
Roger

[RomanLini]

Hi RCaffin (Roger).

We are also discussing this in my "air pump" thread! Thanks for all your advice so far!

[Machining]

So not using a micro drop unit? Can't see this working on aluminum, or tapping.

[Geof]

.....What I noticed was that the real problem was that the cutter got clogged up and the build-up of swarf made the cutter red hot. And then it broke....

I am interested to know your conditions: Type of alloy, cutter type, coated/uncoated, # of flutes, cutter dia., rpm., depth of cut, radial engagement, feed per tooth.

[RCaffin]

So not using a micro drop unit? Can't see this working on aluminum, or tapping.

NOT using this for CNC tapping with a tap. I can't do CNC rigid tapping anyhow. For that I use tapping oil of some sort or other.

See also next reply.

Cheers

[RCaffin]

I am interested to know your conditions: Type of alloy, cutter type, coated/uncoated, # of flutes, cutter dia., rpm., depth of cut, radial engagement, feed per tooth.

Aluminium alloys: the usual range of machining alloys (eg 2011, 6060, 6061), plus some pretty awful 5005 H34 sheet. It's the soft 5005 H34 which really makes life difficult: it's like machining soft copper. But it can be bent quite well ... later.

Titanium sheet, 6Al4V, hard. (Aggresive feed and low rpm here to avoid any chance of heat.)

Some brass, a small amount of steel.

Many different plastics from PVC, PP, PE, through nylon and acetal to PET and PEEK. Also some strange composition material 25% acetal/75% aluminium hydroxide powder (Corain) which machines (fairly easily) like a friable ceramic. The results with that stuff are rather nice.

Cutters: HSS and carbide.
Coating: some bare, some ... I think it may be TiN (gold) on the HSS, and ??? on the carbide (black, TiCN? TiALN? proprietary?).
Flutes: 2 and 4 flutes.
Cutter dia: mainly 2 mm to 10 mm.
RPM: 2500, which is not real high I know. Machine limit.
DOC: usually small at present, but getting deeper with time.
Feed/tooth: ah ... not sure, haven't calculated it out. I look at the chips.

Without the air blast, the cutters seem to be forever getting clogged (esp on 5005!) no matter what lubricant is used. With the air blast the cutter stays very clean, there are no bumps from recutting chips, and everything stays cold. I suspect that high-pressure flood lubricant is really just doing something very similar to the air: just washing the chips away.

Preventing the swarf from sticking to the cutter or being caught up in the flutes seems to solve my problems. (So far!)

Cheers

[RomanLini]

Do you cut full WOC (width of cut) slots in metal? I've recently switched to using two passes for slots, with the first pass at full WOC and the second pass at about 20% of the tool diameter.

Combined with the shallow cut depth (usually under 0.040") this has been helping to overcome some of the shortcomings of my machine ie chip evacuation, because the slot is wider than the tool it is much easier to throw the chips out and not munch them back into the tool. Of course it is double the cutting time and 20% more tool wear...

Maybe now with a good air jet to clear chips I can go back to single cut slots at full WOC?

[RCaffin]

Do you cut full WOC (width of cut) slots in metal? I've recently switched to using two passes for slots, with the first pass at full WOC and the second pass at about 20% of the tool diameter.

Good question. The problem is that relying on the exact cutter diameter to define the slot width means that the slot always comes out over-size. Any movement or backlash in the ways, any radial runout on the head or the collets - they all conspire ... So either I avoid critical slot widths, or I take two passes with an undersize cutter. And I tweak the program to compensate for the odd 20 microns runout etc.

Of course it is double the cutting time and 20% more tool wear.

Commercial or hobby?
Even with commercial, parts not meeting spec are far more expensive... The machine cost a lot more than a cutter, so I try to buy good cutters and not break them. Works for me (except for accidents ...) :-)

Cheers

[RomanLini]

Sorry I should have explained clearer. My problem was not the dimensioning, as my machine will hold good tolerances and I normally used single slots to cut out shapes etc, so only one wall is the item. Or if both walls are on the item I allow tolerances.

The problem is when cutting a single width slot and with imperfect chip evacuation when the tool runs forward into loose chips in the slot there is nowhere for the chips to go and some get munched into the side wall although some get thrown clear or lifted out by the flutes of course.

But the ones munched cause a nasty noise and surface defects in the wall etc. They stress the tool or deflect it into the wall making surface defects.

I'm just wondering if you have experience cutting single cut deep slots in aluminium with the air blower and not having this problem (as the air is giving full chip clearance)?

[RCaffin]

The problem is when cutting a single width slot and with imperfect chip evacuation when the tool runs forward into loose chips in the slot there is nowhere for the chips to go and some get munched into the side wall although some get thrown clear or lifted out by the flutes of course.

But the ones munched cause a nasty noise and surface defects in the wall etc. They stress the tool or deflect it into the wall making surface defects.

Fast, deep slots, good finish - pick 2. Well, that's my take on it anyhow.
I normally go for fast feed but shallow cut so the chips leave the scene.

Cheers

[fseeley13]

QualiChem is a very good coolant. Keep the viscosity around 10%.

[RomanLini]

Thanks RCaffin. I'll stick with fast feed, shallow DOC and a 20% WOC second pass. It's been working pretty good.

[Len Hoffman]

Pulling this thread out of the past. I found it doing a coolant of choice search.
I'm ready bring a Milltronics RW-15 VMC on line in our shop. This is our first cnc machine and we're trying to make the right choice for coolant.
Considerations of importance to us:
-Good for Milling, drilling & tapping Al 6061 and Al automotive castings, which often have some amount of silicon. Finish is important.
-The machine will almost certainly have periods of in-activity that could be more than week or two in duration. Don't want to have to do any time consuming maintenance, but wouldn't mind running an aquarium air pump if need be. And I will be fitting a belt skimmer to the tank.
-Nothing stinky or strong perfumy I have allergies
-Not harsh to skin. One of the guys has very chem sensitive skin.

Castrol 6754. Anyone here have an opinion?
Trim E206? It has some folks here that like it. The price is reasonable. Do those of you using it find it hard on skin, I like that tramp oil floats to the surface. Smell?

Thanks!

[RCaffin]

It pays to very carefully ask what you are trying to achieve in the first place. Sure, you see lots of ads for flood coolants and systems, but that does not mean it is what you need for your application. However, I am sure a lot of coolant salesmen (who obviousaly have a big vested interest in the matter) and coolant devotees will argue vehementally that I have it all wrong.

Thing about flood coolant is that it really was designed for machining steel some 50 - 100 years ago. Even so, it has some serious defects.
* Thermal shock as the hot edge spins around and meets the cold coolant - can damage both HSS and carbide with micro-cracking.
* Limited ability to clear chips away, unless you use really high pressure blasts.
* High cost of coolant, filtration, clean-up, enviromental restrictions, disposal ...

If you are machining aluminium then you have a totally different set of conditions. Steel does not normally stick to cutters but can create serious bumps when recutting. Aluminium is almost the opposite. For what it is worth, in my limited experience, and so on, I find I can get better and cheaper results using an air blast (quite a small nozzle mind you) plus a very light pulsed misting. For the mist I use either straight kerosene or, more happily, a mix of 80% kero and 20% vegetable oil. (Cheap olive oil lately.) I do NOT go for single pass and big DoC.

Misting is NOT the same as flood coolant. With aluminium, what misting has to do is to keep the surface of the cutter 'wet' so aluminium does not stick to it. When you get aluminium sticking you get rapid metal build-up, friction and glowing cutters, quickly followed by disaster. The oil stops that happening; the focused air blast clears the chips from the working area. When the cutter stays clean you do not NEED cooling: the bulk aluminium usually handles that. Finish - depends on the quality of the cutter.

How much misting? I might go through about 100 g of mix in a day. That is not a typo. The parts come out essentially 'dry', with maybe a trace of vegetable oil on them. As far as I know, vegetable oil is not corrosive on aluminium, and washes off with hot water and soap.

I will add that I also use the same mix when maching titanium - with slightly more frequent pulsing. Ti is nice stuff to work with, IF machined correctly with the right cutters, feeds and spins. Steel - I don't do much, but I usually still use air-blast and misting. It works for me.

Cheers

[ALongGuy]

I like Castrol MB50. The best I have personally used. Great tool life. Does no turn rancid.(Sump life in years!!) Protects the machine tool- no rust. Does not stain brass. Does not give me a rash, after all i am sensitive. Well..... at least to detergents and such.