Does isopropanol make a difference?

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[@DDBerlin]

Stefan, I actually tried out what happens when my noga mist coolant with alcohol (spirit in my case) would get on fire. It‘s not as bad as I was afraid it would be: kzbin.info/www/bejne/iZukkKlrqc-KpNE

[@StefanGotteswinter]

Thats extremely dissapointing. I was hoping for a 2m jet of flame :-\

[@dsfs17987]

@@StefanGotteswinter need to let it mist up the enclosure, and then light it up, preferably have a surveillance video recorder running for posterity, could win the Darwin award! 😄

[@rocketplane8862]

If the jet of coolant were hitting a part, you might be able to sustain a flame, but it would probably still be disappointing.

[@spitefulwar]

@@StefanGotteswinter If you keep it running long enough maybe the room fuel mixuture may reach critical levels and you turn your workshop into a pulse jet? ;P

[@DDBerlin]

@@StefanGotteswinter yes, I was expecting that too. Either that or a bad explosion, as the housing of the cnc is quite small. But, at least with the door open, the saturation obviously does not reach a critical point. I found it most calming that the flame dies immediatly once the igniting source is taken away. .... but I remember, I had trembling knees and two persons with fire extinguishers ready, when we filmed that 😅

[@dan4653]

Alcohol is also a penetrant, it loosens up a lot of people. Causes fingers to tend to drop things, and mouths tend not to hold back profanity, etc.

[@sharg0]

One more "danger": It dissolves oil/grease so taking a few extra minutes to make sure things are lubricated and, where applicable, covered with a light coat is a good idea to keep things in good shape.

[@StefanGotteswinter]

Thats the beauty of running way covers and beeing very generous with oiling my machines :)

[@xESPplayer500x]

Try mixing a little oil with a lot of alcohol im the resevoir

[@egaega2458]

@@xESPplayer500x What about beer?

[@dieSpinnt]

@@egaega2458 Read Wikipedia on that stuff. It is toxic ... Okay, Beer (Ethanol) is also ... but our livers are willing to fight it (and are able to do so;) ) Cheers ega ega:)

[@dieSpinnt]

@@xESPplayer500x That makes no sense, because that just evaporates ... Or even worse: It changes the viscosity of the oil completely out of spec. Like in: ... a curve looking like a rollercoaster ... Yeah! Seams to be a good idea;)

[@chronokoks]

Isopropanol even works as a cutting fluid for tapping with hand-taps - even large ones like M22. I did many tests on various aluminium alloys and it simply worked, which was surprising. For a bit of cost-saving you can dillute it with 20% water.

[@sashimanu]

I used PCB wash solution (50/50 IPA and light solvent that smells like lighter fluid) for hand drilling and tapping because it was at hand and it was better than nothing - now I know I’m not the only one to do so, and it actually works good :)

[@danaveye3977]

Worked for an aluminium boat builder (100m + vessels) and we used methylated spirits for all cutting. Works a treat

[@dieSpinnt]

@@danaveye3977 What you describe are higher alcohols and get into the region of oil-like consistency. Isopropanol may have a high cooling property ... because it just evaporates your dollars away;) (which is WHY it is so good at cooling!!!) But the lubrication properties are practically non-existent. Oh and it is also toxic?! Please have a good ventilation at the workplace. That is totally different from a medical mixture of that crap (we used during COVID), which needs a good amount of extras to not ruin your skin ... than inhaling that stuff 8h at the workplace. By the way, people who have not yet killed their brain through isopropanol vapors use: water-soluble drilling milk for aluminum. Anyway ... for the hobbyist .. ESPECIALLY for them: Again and again laypeople mentioned spirits or ethanol as a suitable coolant. However, there are easily inflammatory vapors here, which is why spirit is urgently not advisable. Instead, you should use a suitable cooling lubrication emulsion from the aluminum specialist shop. Have I mentioned that Isopropanol ruins your mucous membranes and it is toxic? Ah yeah ... above:) Take care guys and don't kill yourself. At least not with fancy cooling solutions. I believe in you that you will find other ways. At least while machining ... and not inhaling fumes:)

[@danaveye3977]

@@dieSpinnt you need to consider what comes next, also. We were using methylated spirits because it leaves no residue for the welding process

[@Blondihacks]

One other gotcha with IPA as cutting fluid- if you use Sharpie as a layout fluid, IPA will instantly remove it and spray it all over the place, leaving blue spots all over your machine and walls that are impossible to remove. Ask me how I know. 😐 I believe Dykem is fine, but so many of us use Sharpie for quick layout tasks.

[@brianmccusker3852]

Always a treat to view one of your videos. Thanks Stefan, cheers.

[@KingSlimjeezy]

you are a Master of your craft and an absolute treasure. You have taught me so much it is unreal! This one i did know but still, your execution is so always so clean i just like watching

[@j.dietrich]

Regarding the safety hazards, the lower explosive limit for isopropyl alcohol is 2% - below that concentration, the fuel/air ratio is too lean to sustain a flame. Even in a small, fully enclosed machine with zero ventilation, you would need to evaporate tens of litres of isopropyl alcohol to create a risk of explosion. The actual consumption rate of a mist/MQL system gives us a generous safety margin. The NIOSH/OSHA health exposure limit for isopropyl alcohol vapour is 980mg/m^3; that limit is a weighted average over a ten hour working day. If you're running a machine constantly you would obviously want a local exhaust ventilation system, but in a hobby shop or toolroom application with intermittent use I would generally be happy to rely on normal ventilation.

[@donteeple6124]

Have been watching you use this for yrs and after this close up, I am finally going to begin using it myself now...Thanks.....

[@SwitchAndLever]

We tend to use ethanol as a cutting fluid when turning or milling aluminium, less so for the lubricating effects but more for the cooling effects as aluminium tends to bond very well to tooling when it gets even a little hot. Sure it lubricates, and from a surface finish point of view as demonstrated in this video, but don't discount the cooling factor from it flashing off. It's really good at pulling heat out of aluminium.

[@robertpearson8798]

I would have suspected that and was surprised it wasn't mentioned. It certainly has a cooling effect on the skin.

[@Gottenhimfella]

I've been doing the same ever since we got left with a drum of the stuff after commissioning a depositor upgrade for a hand sanitiser bottling plant. I'm sure you realise that the cooling effect (which as you say, prevents formation of a built-up edge) plays directly into better surface finish on gummy materials like aluminium and copper. A high value for enthalpy of vaporization (aka latent heat of evaporation) On that score, isopropyl alcohol (~44kJ/mol) scores higher than water (41) and ethanol (39) which in turn is higher than methanol (35). However I suspect that the extra volatility of alcohols (lower boiling point) makes the rate of evaporative cooling higher than for water, I did wonder if alcohols' apparent lower viscosities will translate into better cooling at the micro level than what I took to be a more viscous substance (ie water), which is what matters because the BUE formation process is essentially microwelding, and point of contact temperatures at that scale can be many hundreds of degrees hotter than the surrounding surface. However I checked and, to my surprise, alcohols are slightly more viscous than water . I think what I interpreted as "thin" behaviour is actually a better wetting action. This is clearly highly important for cooling, particularly at the micro scale.

[@stanseel8900]

I have been using alcohol for a few months now based on your recommendations. I did try a few different grades. Even some cheap 100 proof grain alcohol. I found the best was pure isopropyl based off its abilities to flash off so quickly. The grain alcohol did work, however the water content caused corrosion issues in my very harsh environment in south texas. Isopropyl is a perfect cutting fluid for me because of the flash off. It worked well on the mill but had a tendency to not stay put. That's when I discovered the hand sanitizer we have become so used to over the past few years. It stays put and keeps the cutting abilities. How ever it does trap the chips so you will need to clean before you do your final finish cuts.

[@stumccabe]

I learn something from every one of your videos Stefan. Thanks.

[@BruceBoschek]

Thanks kindly, as always, for your excellent description and discussion on alcohol lubrication.

[@MachiningandMicrowaves]

I started using neat IPA after you showed it on the flatbed CNC video. Before that I used a mix of light ester-based cutting oil and IPA. Now I use a mister or a dropper bottle with pure IPA on aluminium and small Tellurium Copper parts, and even sometimes on brass to get the best possible finish

[@outsidescrewball]

Always teaching/sharing your knowledge/experience in a fashion of “no brag, just fact”….thank you

[@nefariousyawn]

I took your word for it previously, but that demonstration was still very interesting to illustrate the point. Thanks!

[@Michel-Uphoff]

Same here Stefan. A few past corona leftover small spray bottles filled with bio-ethanol serve me well. I spray a mist on the aluminium to turn or cut. Works like a charm, better surface finish and no mess. And I noticed there is also considerable less chance off friction welding. It is a pity that during the second turning in your video a long chip wire from the previous operation obscures the view of the chip formation a bit. What I notice when I use alcohol, is that the chips curl much tighter and break down quickly. I suspect it has to do with the rapid cooling by the alcohol.

[@Preso58]

Good demo. I've used denatured alcohol as a lubricant for aluminium and copper. We call it methylated spirit here in Australia. It's easier to get and cheaper than IPA. But it stinks a bit compared to IPA.

[@Engineerd3d]

Awesome finish. I have to add this to my arsenal.

[@TheAyrCaveShop]

Good info and demo Thanks Stefan !

[@maxschumacher9446]

When I was working in an Anodising shop we used IPA as our drilling and tapping lubricant for aluminium, found it pretty good but had to keep the respirator on or I'd go home light-headed. Just a shame we couldn't use it to lubricate our linishing wheels as well, we used a mixture of 60:40 coconut oil and candlewax for them, made a mess but produced a great finish. Somewhat fittingly the best clean-up agent for degreasing the parts after grinding them and before anodising them was a 70:30 mixture of IPA and Orange Oil. The orange oil has the side benefit of making the shop smell a lot nicer.

[@drevil4454]

We used IPA in a clean room manufacturing lab exclusively. It is actually a safe lubricant to use IF you know what to do. We worked mainly with Stainless, Titanium and Tantalum.

[@dieSpinnt]

For the ordinary KZbin viewer it is a fire hazard, explosion risk ... a toxic substance they can easily get ... and a waste of money. Instead, you should use a suitable cooling lubrication emulsion from the specialist shop. For Alu, Titanium, Tantalum, Steel ... even for Sodium:P (forget that last, hehe) They have so much of those appropriate cooling fluids there, that they even have to sell it!

[@drevil4454]

@@dieSpinnt 🤣🤣🤣🤣 true and funny. Not applicable to a sterile clean room though. Static and cleanliness is a bitch once you start incorporating glycol and other chemicals. In a cryogenic temp controlled clean room you want to use as few chemicals as possible to prevent cross contamination. I'll stick with IPA 99.997% purity.

[@feedbackzaloop]

@@drevil4454 what kind of appliencies require being manufactured in criogenic conditions though?! Or is that you use the clean room for different processes...

[@drevil4454]

@@feedbackzaloop think micro processessors, instrument making, optical lens processing.

[@drevil4454]

Cryogenics are used where you need ulrra high vacuum. You cannot "empty" chamber under normal temp. We're talking -200 deg C, you can also used it where you need to split atoms etc, etc. It has many applications. You can also goof around with it....🤣🤣🤣

[@wrstew1272]

Great photo work!

[@HM-Projects]

Great video. I've already had great success with IPA on Aluminium after seeing you use it. Chips come off cold to touch! Best tip I've had for dealing with 6061 galling on inserts

[@ScheunenTecCNC]

Hi Stefan, thanks for showing this difference

[@Rustinox]

It's almost magic. Plus, alcohol doesn't make a mess like cutting oil or coolant. BTW, very nice close up.

[@angelramos-2005]

Very interesting,Stefan.Thank you.

[@AmateurRedneckWorkshop]

Thanks for another interesting video. Keep on keeping on.

[@CSWeldFab]

Thanks for the information. I've been researching different flood style options, for when I finish the mill I am currently restoring.

[@StefanGotteswinter]

(I would not run it as a main flood cooleant option - I have it mostly in small needle bottles, to keep the useage of it to a minimum.)

[@TrPrecisionMachining]

very good video stefan,,thanks for your time

[@russellhayward2359]

I've been using IPA on aluminium, on both my.mill and lathe since watching your videos. No mess to clean up either. Just evaporates in no time 🙂 Thanks for the video 👍

[@DavidKutzler]

Not really a fan of India Pale Ale. What are your thoughts on hefeweizen?

[@michaelandersen7535]

Hefeweizen doesn't make as good a lubricant - very dirty. But it cools you down ok

[@chrispoirier384]

I have seen trichlorothane used on kovar, it is volatile and evaporates rapidly and cools the cut. Also I have seen phosphorized/chlorinated 30wt oil used on brass and it makes a huge difference.

[@joell439]

👍👍😎👍👍 Thanks Stefan for the lesson - I found it very fascinating and look forward to trying it myself.

[@bigmotter001]

Outstanding Stefan! I will be trying and maybe converting my mister to alcohol for some projects. Thanks for posting for us and take care! John in USA!

[@billshiff2060]

I use a lot of that. I don't think it acts as a lubricant per se. Instead it seems to prevent adherence. It is well known to remove hot glue too so possibly it prevents aluminum from sticking to the tool. I have 3 tips for you. I add isopropanol to my tapping fluid and cutting oil to get the benifts of both. Secondly if you are sanding/scotchbriting aluminum the isopropanol miraculously removes ALL aluminum from the sand paper/scotchbrit and really enhances the surface finish you get while greatly extending the life of the paper. Thirdly when filing aluminum isopropanol will keep the aluminum from sticking to the file teeth.

[@davidsomerville7868]

I've used IPA for years on aluminum. I also think there's a major cooling effect. I don't do it as much on surfaces but absolutely on drilling, reaming and tapping. Drilled holes are more accurate in size with IPA. I've recently done a 6.5" cube with thru holes, large and deep counterbores and tapped holes. It's the first time that I experienced IPA parts per million in the air that I had concern with air quality. Using a fan and stepping away was the remedy. I'm also in Phoenix, AZ (dry and hot) and haven't had any issues with static, fire or explosion.

[@hardwareful]

I'm using IPA as a tapping fluid for M3 and smaller. High viscosity tapping fluids just seem to turn the swarf into an aluminium paste, while with IPA one can get the dry powder out of the hole just fine.

[@brandontscheschlog]

I was literally just turning aluminum and saw this video and thought I have to try the isopropyl alcohol. I can’t believe how well it works. I was using WD40 and it worked OK but the IPA gives a much better surface finish. The IPA has now replaced the WD40! Thanks Stefan for making this short vid and making me a believer.

[@nunyabusiness8538]

Does it have the same effect with other metals or is it something special about the properties of aluminum

[@dieSpinnt]

@@nunyabusiness8538 It has just higher evaporation properties as normal cooling fluid. And of course as oils. Cool your suitable cooling lubrication emulsion from the aluminum specialist shop (which will be cheaper than evaporating alcohol like a moron, a.k.a. throwing money out of the window!) and you will achieve the same effect. Without risking your health or introducing a fire or explosion hazard without any need. Principle: The friction of the cutting tool also causes a lateral expansion through the temperature coefficients of the workpiece and the tool. To put it simply, the central surfaces lead to a mutual dance from sinusoidal nature and that is overlaid by the temperature coefficient of the overall system. As with a record press, this is expressed as a surface structure with the thermal instability of the overall system. Optimal cooling reduces this effect ... which results in lesser "noisy grooves", meaning a better surface. Alcohol is very effective for cooling ... if he reaches the areas to be cooled at all and does not evaporate beforehand :) So is the APPROPRIATE FLUID which may be cooled beforehand and does not poison you or burn .... You get it. I don't like wasting your money or your health for little to no benefits. BTW that aluminum oxidation should be that fast (or of importance [1]) is new ... and wrong, hehehe:) [1] about 1-5 μm after minutes(!) in oxide-layer-thickness. Which does not change the overall material thickness.

[@Gottenhimfella]

@@nunyabusiness8538 Gummy materials which tend to form a built up edge (including some grades of mild steel) give improved results (on finishing passes, in particular) from pre-application of permanent marker pen ink. I presume that IPA would have a similar result, but the ink stays put until the cut, and the lathe operator is not distracted by having to apply flood coolant. If a cooling effect is also desired, obviously IPA or ethanol are preferable.

[@spehropefhany]

As to water used as a lubricant, in Toronto the streetcars had water running 24/7 (at least in the summer) to wet the tracks at turn-around points to cut down on the squealing where the streetcars turned in a tight loop (steel on steel). They may have replaced them with something else like flange greasers, but that system was used for decades. Wastes a bit of water but seems more environmentally friendly than grease to me. There's plenty of water in Lake Ontario, not far away and where the city gets its potable and district cooling water supply from.

[@Smallathe]

Very cool demo!

[@Perius]

I've been using alcohol as cutting fluid for aluminium since I started as an apprentice in 1996 at a University's prototype lab. I was told at the time, that because of the low boiling temperature of the alcohol, it's much more efficient at cooling the chip and the tip of the tool, which prevents build-up of gummy aluminium that creates a bad cutting edge and gives a horrible finish. At home, if I don't have any pure alcohol, I have used anything from paint thinner, acetone, brake cleaner and what not to varying degrees of success. I would absolutely not recommend this to people, since they are highly flammable liquids and are most likely anything but healthy fumes.

[@steveggca]

Hi Perius 99.9% ipa is commonly used in electronics ,any well stocked electronic component store will have it on their shelf. I live in canada, MG chemicals brand #824 C $20 /L actually much cheaper than drug store ipa

[@jdsstegman]

That's a big difference. I know I will be using this info. Thanks!

[@mattholden5]

That's a huge difference in finish. Seems to help break the stringy chip as well. You have mentioned a few time how to 'cheat' very small tolerances by altering cutting fluid viscosity. I'll be testing low viscosity fluid with my high-positive inserts now. Thanks, Stefan. Very useful tip.

[@bill4639]

Tap magic for aluminum works really well when working with aluminum as well.

[@crichtonbruce4329]

Hello Stephan. Was this the shortest video you've made? You are answering a question I've had. I mostly assumed you used alcohol because your parts are often so small and fragile you needed something very clean (indeed, self cleaning) for a lubricant.

[@tahustvedt]

Been using alcohol to cool alu for many years. It's pretty great and clean compared to any other cutting fluid. I've got a DIY mist cooler on my CNC router for this and also ventilate the chamber to the outside. It's awful without ventilation off course. :)

[@sebastianhorvath2123]

Thanks for the cool demo video! Do you also recommend IPA for manual machining of copper? I occasionally machine some OFHC parts when we're too time constrained to send the job out to a professional and tend to use conventional oil (not always with great results).

[@wizrom3046]

I use ethanol and isopropyl alcohol in the workshop sor some cleaning processes in electronics. One big danger is breathing the fumes. The fact that it flashes off almost instantly means every liquid drop turns into vapour and then it is in your air, right in front of your face. Ethanol is less toxic than isopropyl but this is still a problem! At times I have felt quite sick after using alcohol for cleaning, even when trying my best not to breathe it it... Something people may not consider is that if the alcohol cleans off the oil or other substance, then the alcohol evaporates, the oil or other nasty stuff etc is contained in the alcohol fumes which you then breathe in! That can result in a much more toxic vapour than just alcohol vapour. REALLY, you should be using a fume hood to ensure 100% fume extraction and removing it from your breathing environment. I wont use alcohol for machining, I would much prefer a light machine oil that does not evaporate, so OK i need to clean up liquid residue but to me that is MUCH better than breathing in all my "lubricant". 🤔😬

[@el1260]

Das kann ich nur bestätigen! Ich wollte vor kurzem ein Stück Aluminium ausbohren mit einer Bohrstange (Wendeplatte für Aluminium), was zuerst grosse Probleme machte. Da das Aluminium von schlechter Qualität war (sehr weich und "klebrig", irgend ein Stück aus dem Alteisen) passierte es, dass es mit der Schneidplatte verklebte und die Bohrstange einfach weggedrückt wurde, was das drehen praktisch unmöglich machte. Mir ist dann in den Sinn gekommen, dass Du bei Aluminium Isopropanol als Schneidflüssigkeit verwendest und habe das ausprobiert und siehe da, das Drehen ging plötzlich perfekt, die Oberflächengüte war ähnlich gut wie in deinem Beispiel! Vielen Dank für solche Tipps

[@StefanGotteswinter]

Freut mich zu hören :-)

[@christiansprojects-cgmanuf1426]

I work for a company that operates high vacuum magnetron sputtering plants for PVD-coating. On machine parts that are used in vacuum, cutting fluid can‘t be used as its remainigs would later outgass in vacuum. Also, most parts are made out of stainless steel as you can‘t use paint in high vacuum. We use Isopropanol as a cutting fluid even for stainless steel. Its well known in the High-Vacuum or Ultra-High-Vacuum industry.

[@StefanGotteswinter]

Thank you, thats interesting! (Vacuum and cleanroom parts are also for me an application where I try not to use anything but IPA)

[@christiansprojects-cgmanuf1426]

​@@StefanGotteswinter Gerne. Ich war 7 Jahre lang für eine dieser grossen Architekturglas-PVD-Coater (100m lange Vakuumkammer von Von-Ardenne Anlagentechnik) zuständig. Wir arbeiten da in einem Druckbereich von 0.000005 bis 0.005 mBar, welcher bei dieser Grösse von Vakuumkammer mit Ca. 200 Turbomolekularpumpen erreicht wird. Bei diesen Drücken dürfen sich keine organischen Rückstände an irgend einem Teil befinden - also keine Öle oder Schmiermittel in konventionellem Sinne. Zudem wird in diesen Anlagen oft V4A in Kombination mit VA-Schrauben verwendet - also alles eher unangenehm für Nachbearbeitungen, Nachfertigungen oder Reparaturen. IPA haben wir für fast alle spanabhebenden Verfahren gebraucht, wenn wir V4A bearbeiten mussten. Sogar das manuelle Nachschneiden von vermurksten Gewinden in der Anlage geht mit IPA viel, viel besser. Auch die Bandsäge haben wir häufig mit IPA gefüllt, um V4A Rohmaterial zu sägen. Die Standzeit der Sägeblätter war damit signifikant höher. Betreibt man Maschinen mit Überflutungsschmierung mit IPA, sollten man Schmierstellen und Dichtungen der Maschine gut im Auge behalten. Billige NBR O-Ringe können spröde werden und Stahl kann rosten, da IPA hygroskopisch ist und somit Wasser anzieht. Viton (FKM) O-Ringe eignen sich da hervorragend. Gruss, Christian

[@humanistwriting5477]

Alcohol, kerosene and compressed air: three lubricants and coolants that I absolutely love for aluminum. I am surprised you had to make this video, they are right there in the handbook! That said. When cut pressure is higher, you need thicker lubricant. Thats the rule of thumb, its not perfect there are other ways around it and sometimes you want things to get absolutely red hot un the cut and then you dont usually want coolants or lubricants. And you can absolutely use lube as thin as air or liquid nitrogen plenty of options avaliable.

[@greglaroche1753]

An interesting topic, but brings up the topic of comparing other lubricants like WD-40 or the special lubricants made for cutting aluminum. Here in France, ethyl alcohol is very commonly used. Would it be safer for the environment ? Thanks for the video.

[@godfreypoon5148]

@@greatestevar It smells quite different.

[@swanvalleymachineshop]

Well , who would have thought ! Great result . 👍

[@groundcontrol6876]

That is a VERY nice finish!

[@Sigmatechnica]

My understanding of cutting aids was it was more about the abiity to react with the freshly exposed metal forming an innert layer so you don't get cold welding occour after the cut. those OH groups on alcahols help with that a bit. make me wonder what glycerol would be like.

[@JohnnieBravo1]

I can't believe you posted this. I have used a spray bottle of isopropyl alcohol for years on aluminum and plastics. never tried it on steel though. I never read it anywhere, or was taught it by anybody. I just had a spray bottle of it one day, no WD-40 or anything, tried it, and it seemed to work okay.

[@billbaggins]

Beer is alcohol and a necessary brain lubricant in my creative process🍺 Enjoying these regular flux capacitor installments now that you are having time off. Cheers Stefan 🍺👍

[@DEtchells]

How interesting! I never would have thought of IPA as a lubricant/cutting fluid, but the results speak for themselves!

[@lesmaybury793]

Intetesting demo. I use IPA on ally these days because I'm a good old boy and does as Stefan tells me too. In the old days, working in a fsctory machind shop back in the 1960s, we would use paraffin (kerosene to non-brits) and I still do sometimes as it is cheap and I have a load of it but it needs a good clean down and rust prevention after use. I' m surprised it doesn't get a mention from time to time.

[@markmuranyi9289]

Stefan. I have been using 100 percent isopropyl alcohol for many years when milling and drilling aluminum as it produces a better finish and does not leave any mess to clean up after.

[@rickhaass1133]

I was going to ask what percent was best to use... assuming the 100%?

[@cyrucom]

Very interesting, I never would have thought of that but it makes sense. Return of the lathe compound slide? And is that a powerfeed on the compound??

[@somebodyelse6673]

I didn't expect that big difference. I'll have to check out my machines for alcohol-vulnerable plastics.

[@seanbrinlee4752]

Right after i watched this I had to run out to the garage to try it! Amazing!

[@MichaelMoranGearHead]

Useful information. Thanks. :)

[@nigelleyland166]

I use alcahol when turning aluminium on the lathe, I do not find it makes any noticable difference to the finish, however if I use enough, I could not care less!😀

[@emiliog.4432]

It seems that the cooling/evaporative affect is good. Maybe adding something to IPA? Alcohol can also discolor some plastics.

[@williambramer8217]

I’ve been using white spirit as coolant/lubricant on aluminium. I am now motivated to give IPA a try

[@migalito1955]

Cool beans with respect to the finish. All my machining is actually closer to milling and related strictly to wood where in my retirement I craft stringed instruments. But, there are times when I really don't want an oil to be absorbed into a piece I have in a drill press because of its downstream effect on applied finish and I would bet IPA would provide the required reduction in friction here too.

[@dylanschulz2404]

A combo of wd40 and ipa works really well on aluminum. I ran a mist set up with that mixture on my VMC as a test. Worked great but definitely need a mist collection system as it fogged out my shop! Thanks for the video.

[@sessilian]

There are some academic papers (I need to look up the refs, but I think it's in Phys Rev Applied) that proposed alcohols oxidize the surface of the alumin(i)um. This improves the chip forming properties of Al, improving surface finish.

[@machineshopinagarage4699]

Great demonstration Stefan, just shows the variety of cutting fluids used in industry. I remember machining Tantalum with the recommended cutting fluid of Trichlorethane 1.1.1. Wouldn't do it now though!!! Regards Ian

[@StefanGotteswinter]

O boy. I am glad we dont use Tri anymore the way we used to.

[@gamemeister27]

Apparently it's not that toxic, but the whole ozone depletion thing is scary

[@machineshopinagarage4699]

@@gamemeister27 it's classed as a carcinogenic and has been phased out after the Montreal protocol, due to ozone depletion. Great for dry cleaning though! The company I worked for made the stuff.

[@gamemeister27]

@@machineshopinagarage4699 yeah, "not that toxic" is relative to chemically similar compounds, should have specified

[@machineshopinagarage4699]

That's why they don't put it in Tippex any more! Office staff were sniffing the bottles!!!

[@CamStLouis]

Great video! You've earned a subscribe from me - this sounds really helpful to use in my woodwind shop!

[@Mr.Avuncular]

A world of a difference in finish quality!👍

[@davidcolwill860]

I will have to give it a try!

[@Gorhamn5]

Are we going to ignore the fact that Stefan has refitted his compound?

[@StefanGotteswinter]

Its just sitting temporarily behind the solid toolpost for this project.

[@sylvaingervais247]

Merci Stefan pour toutes tes truque de machiniste

[@nraynaud]

Interesting. A paper suggest that IPA only works with Aluminium and it is a chemical reaction the DOI is 10.1103/PhysRevApplied.10.014009 As visible in your video, they suggest it's helping with chip breaking.

[@kurtkrause7151]

The immediacy of the alcohol- evaporation gives a much better cooling effect. There are some experimental coolants being developed that are classed as simply H2O, because the formula would be copied by every shop in town otherwise. Great video Stefan!!

[@ominguti6345]

Cool demonstration. I mix isopropanol with very light oil 50/50 and I use this for machining and tapping aluminium. I never tried straight iso. Perhaps oil is not required? I have to test just the alcohol next time.

[@FesixGermany]

I used IPA for drilling and cutting threads in aluminium for years and it makes a huge difference for me.

[@ianjefferson9518]

Was that a bit of chip weld on the insert? Great short little demonstration like others commented I've added IPA to my repetoire, erm both TBE beer and the cutting fluid :-)

[@pirminkogleck4056]

Thx for the vid! I recently added Isopropyl Alkohol in my tinyverse and ITS awesome! Enjoy New Zealand!

[@darkobul1]

I saw it from you and used it ever sense in small amounts. I think is much better then w40 for aluminium for me and my hobby. I used it on some stainless with great results in finish. It seems its material dependant and with some steel it did not work equally well. But on stainless it made part cool after cut which was curious to me. While on some steel would have opposite effect. I wonder is there some chemistry going on there as well.

[@cncdojo1969]

came from a place that does diamond turning for optical mirrors I can confirm that is what they use for coolant

[@andyash5675]

When I was about ten years old and learning to turn, trichloroethane was a legitimate substance. They used to make liquid glue for plastic kits from trichloroethane. As a kid I just did what I could with what I had to hand. Well I can re-enforce that trichloroethane makes a fantastic cutting fluid. I'm completely happy to accept that IPA has a similar effect. I wondered why. I still suspect it is something to do with the evaporative cooling effects. I'm pretty sure that it's nothing to do with the lubricating properties. I'd love to understand why though.

[@neilscully6597]

The Datron machines are fantastic. I bought one at the company I worked at a few years back. Super precise and a phenomenal stock removal rate. The Ethanol mist coolant really works even with high stock removal rates. Not. Cheap machines but worth every penny and nice to be able to buy something made in Europe. Also great product support.

[@StefanGotteswinter]

I ran a M3, M35 and a M10pro at work, I agree, they are awesome machines. They have some problems, but in overall great machines :-D

[@neilscully6597]

@@StefanGotteswinter The machine I bought was the M8, we used it for electronic enclosures. The only trouble I had was a blockage in the mist coolant, a bit of weld debris from the pressurised container, but it took days to diagnose why the parts were distorting and then longer to find the little blockage.

[@sheph7]

fascinating, thanks for the excellent video

[@ianrenshaw6653]

Thank you Stefan. Will it encourage rusting of the lathe parts?

[@StefanGotteswinter]

I heard horror storries, but my machines are completely dripping from cutting and way oil, so for me its a no-issue.

[@felixm.8910]

If I am not mistaken, the feedrate of the tool was 1,5 times as long when running lubricated as it was when you were cutting it dry (10 vs. 15 seconds). So it seems to be a bit like comparing apples with oranges if the setup should be identical. Despite that the benefits of IPA on aluminium are clearly there.

[@StefanGotteswinter]

Copy/pasting my reply to here too :D yikes, so much for a scientific experiment ;) Yes, youre right, but: Feedrate doesnt influence the "shine" of the surface finish much. There is surface roughness on a macro level (The turning marks) and on a micro level (The material itself, how it cuts and flows across the cutting edge) - The lubricant influences mostly the micro surface finish. Example: You can have a extremely shiny surface with super visible turning marks)

[@TheMiniMachineShop]

Excellent thanks!

[@rootbeer666]

Years ago I did this milling aluminum on my Chinese desktop CNC. I got great finish quality with IPA.

[@Stefan_Boerjesson]

Since 55 years I've been using, as we name it, White Spirit, denature alcohol, when drilling aluminium. It prevents the aluminium from sticking to the drill. The same works well for turning. Today I use Red denatured alcohol. Cheap stuff... Never had any fire drilling aluminium.

[@7alfatech860]

I wonder if it is really the same thing. In the US, denatured alcohol is ethanol (2 carbons) with additives to make it poisonous to humans. Typically 5-10% methanol (one carbon), which can cause toxicity when consumed even in small quantities, but the additive may also be gasoline, acetone, castor oil, IPA, etc. IPA is iso-propanol, or propan-2-ol (3 carbon). It can be purchased as 100%. In medical use, eg cleaning skin, hand sanitisers, it is typically used at 70% concentration. Though ingestion can lead to CNS and respiratory depression. Propan-1-ol is I believe more toxic, and typically not readily available. Glad to hear about no🔥with the denatured alcohol😀

[@Stefan_Boerjesson]

@@7alfatech860 In the past it was pored into the gas tank on gazoline cars to absorb water. Yes, poison is added to make it impossible to drink. No other additives as I know.

[@merlin1943]

It’s also great for drilling and tapping in aluminum

[@jothain]

Machine shop in my hometown did CNC aluminium parts. They apparently used IPA and one night the entire plant burned down to ashes with remains of barrels next to machines couple decades ago 😐

[@albertthesecond210]

Bacon grease as a cutting lube gives an awesome finish on aluminum. Not only do you get a great finish but a "perfumed" shop. Thinning it a bit with kerosene works.

[@kerkkonenahaima7322]

Here in Finland we do solve all of our problems with alcohol. The results are much varying in other fields than cutting metals. Denaturized spiritus is mostly used as cutting aid to aluminum, I must give a try to IPA now. Inhaling all day alcohol fumes gives quite sore throat without any positive effects. There is a myth about the alcohol as cutting fluid: If you stop using it, aluminum will stick on your tools as they get dry from any greases. I think there may be some truth behind it. Did I hear some kind of power feed on that so hated compound slide?

[@tannerbean3801]

IPA is quite a reliable lubricant to break fasteners loose, especially cold welded stainless fasteners in aluminum threads. I used that all the time in semiconductor mfg equipment maintenance. It's like magic.

[@troyam6607]

Thanks Stefan, its a shame you cant reuse it and cycle it around the part to save on wastage but i will be trying it out on some ali now. do you think you would get the same results with 70% IPA?

[@scottrey]

I use alcohol every time I drill aluminum since watching a previous video of yours. Thanks

[@dimman77]

Stefan, I started experimenting with isopropyl after watching your previous video on it. I've successfully micro milled (0.2mm cutter) 304L and 316L stainless steel and 6Al-4V titanium on a Chinese gantry router (some vids on my channel). And it keeps parts cool and clean. Invaluable tip. Thanks!

[@StefanGotteswinter]

I would be very careful machining ferrous materials like stainless or titanium with IPA, to be honest. Thats a case where a spark might very quickly occure and create problems.

[@dimman77]

@@StefanGotteswinterThanks. Fire extinguisher is right beside the router. So far I haven't had any sparking issues with titanium with any coolants or even the occasional short dry cut. Only time it sparked was deliberately in the spark test video I made on a belt sander. But I do have some 702 zirconium alloy stock that is NOT going anywhere near that router.

[@StefanGotteswinter]

@@dimman77 Zirkonium is fun 😬 I did some turned parts out of it and its nerve wrecking when it starts to spark out on you.

[@dimman77]

@@StefanGotteswinter I drilled through a piece with a hole saw at slow speed on a drill press with no problem. But on a belt sander it's like white fireworks... Is it a certain surface speed where it goes from cutting fine to spitting sparks? I imagine chip size plays a factor too, the bigger the chip the less likely to spark?

[@lagunafishing]

I bet finishing with an alcohol soaked cotton wool pad would bring it up to a mirror finish. I will have to try it.

[@emilgabor88]

It would be nice to compare the results also whit coolant, for the finish