Kool Mist clone ...

[wquiles]

I see a "Kool Mist" in these applications as a lubrication dispenser, not a "Cooling Apparatus", especially when I see so many carbide inserts. As most probably know carbide likes to run "Hot", this way the heat is removed from the tool and the part by the blue hot chip.

Actually it does both, as the cooling and lubricating effect reduces the BUE (which is temperature and pressure related). Less (or no) BUE means better finishes, so I almost always used some sort of lubrication when cutting metal, although now-a-days I use an Accu-Lube system. Of course you are 100% correct that for some operations/materials you do want the carbide to get hoter, but for the projects I have this has not been the case (yet!).

Yet another reason that light finishing cuts are not the forte of carbide. Much nicer "finishes" can be had on aluminum with sharp HSS bits.

In my opinion, this used to be true, but it is no longer the case. Getting a fantastic finish on Al is now trivial with carbide tooling, specially the positive geometry inserts specially developed for Al, which available from several vendors, such as these ones. True, a lot more expensive than HSS, but the harder carbide stays sharper longer than most HSS tools. When the edge gets somewhat dull, I just turn to a new edge and keep going, without having to adjust anything.

With those same inserts I even get near mirror finish on copper as well:

For me, I do honestly believe that HSS tooling has its place (and I "do" have some HSS tools that I learn to grind myself - a great skill to have), but except for a few specific times, I use carbide inserts for 99% of all of the projects that I do in Al, steel, and plastics, and I only recommend carbide insert tools for beguiners as (except for the higher cost) they are a much quicker and consistent way to get started in the hobby since the designers of the carbide tools and inserts have already figured out the right angles for us. Yes, this means that you end up with more tooling for each need, and the costs are substantially higher than grinding your own HSS tooling, and with HSS tooling you have complete control of all of the angles, but, it is still easier and more consistent with the right carbide tooling.

I am "not" trying to start an argument about this. This topic comes in various forums I belong to at least 3-4 times each year, and I see no end to the discussion as we all use what we like and what we feel comfortable using. There will always be the two camps, and there is nothing wrong with that - we can always agree to disagree, and concentrate our efforts in our projects and ideas ;)

Will

 

[precisionworks]

carbide likes to run "Hot"

Some coatings, like AlTiN, are optimized to run dry & hot, but most inserts do better when run cool or cold. The reason is plastic deformation. As most inserts becomes very hot, the binder starts to soften which allows deformation of the edge of the insert. Experiments have been conducted where liquid nitrogen (-320°F) was directed at the cutting edge, which allowed machining titanium and other hard metals around 400 sfpm ... rough 200% of normal speed.

http://www.hardingeus.com/?pageID=23&nid=144

 

[cozybldr]

You can buy just the adjustable nozzle from Kool Mist directly. It is about $14 plus shipping.

FYI.

 

[KC2IXE]

I bought a Kool Mist today (was getting tired of flood on the lathe, and a brush on the mill), and was shocked at just how MUCH air the thing uses - my little 5 Gal tank compressor keeps cycling

 

[precisionworks]

5 gallon compressors usually run anywhere from 2-4 scfm. Mister units need a minimum 3 scfm (1 hp) to 6 scfm (2 hp). The hp numbers are well fed work horses, not scrawny Chinese ponies :D

 

[wquiles]

I bought a Kool Mist today (was getting tired of flood on the lathe, and a brush on the mill), and was shocked at just how MUCH air the thing uses - my little 5 Gal tank compressor keeps cycling

I had a little bit of a similar challenge with the 20 Gal tank I was using on my 1.5HP Eaton (about 5-6 cfm), but the compressor was not quite running all of the time, so the larger tank certainly does help.

 

[KC2IXE]

I said 5 gal - probably more like 10 - but whatever - home built from a Tank Dad brough home a a few decades ago - and yeay, it's a real USA pump and motor on there

 

[KC2IXE]

Found out something interesting - the fluid that KoolMist supplies is a really GOOD dyekem remover :(

 

[wquiles]

Found out something interesting - the fluid that KoolMist supplies is a really GOOD dyekem remover :(

Darn - I did not know about that either :shakehead