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msalm
01-04-2008, 03:54 PM
I'm in the process of getting a little shop set up and I've been wondering about the value of having coolant with the lathe. I've got a SouthBend G26T (13X36 lathe) that works very well and would be interested in how often some of the more 'active' gunsmiths on here use their coolant system, and if they have any problem with it going bad on them over time, rusting their equipment, too much mess or hassle to deal with, etc... I'm not talking about a flood system for chambering, just your standard pump/tank system.

I included a couple pics of the 'work' in progress. Lathe and mill in place, bench still in refinement stages...need more storage to keep thing off the benchtops!

BTW, this forum is SO helpful with all the experts here and their willingness to share their experience.

best regards

J. Valentine
01-17-2008, 08:34 PM
Shop looks real nice and roomy.
Coolant is definately useful for some machining jobs and will extend the cutting life off carbide inserts by preventing tip overheating.
If you intend machining tool steels and some of the harder materials then coolant is a must if you want to prevent cutting tool failure especially at the higher surface speeds . Also coolant will give a superior fininsh compared to dry cutting. Except on cast iron which I cut dry as the coolant seems to clog up the cut.
You have to buy a quality soluable oil that is designed not to cause any corrosion.
Rustlick should have a suitable product.
Dont just leave the coolant on the v-ways and bed after use , wipe the lathe down and dry it with clean cloth then brush on a thick layer of Slideway oil.
Something like Tonna S68 .
Coolant for lathes that are only used occasionaly is a problem because the coolant will gather oil on the surface in the tank and go bad eventually.
The best coolant tank is one you can get at easy and remove the coolant for cleaning .
How I clean my tank and coolant is I pour it all into a white plastic drum that has a tap in the bottom about 1 " up from the inner base.
Let the coolant settle for a few days. The tramp oil will come to the top. This allows you to tap off the coolant from the bottom through some gause cloth into a clean container. Clean the tank . If you need the coolant straight away then refill the tank and top up with a newly mixed batch.
If you dont need it straight away you can leave it in the sealed container one that blocks any light getting in.
You can buy biosides to treat smelly coolant but I just renew it when it is crook.
You should search all posts by Rustystud he is very experienced.

gunsmither
01-18-2008, 01:05 PM
Nice shop msalm! Looks like you have lot's of room to grow. Good idea to have a large area to fill up!

I used to have a flood system on one of my old South Bends, but no longer bother with it. It really helped produce a fine finish on anything I cut, but for most small jobs coolant is too messy on an open machine in my experience. It flew all over the place, and it also left wierd dark stains under places were it got stuck; didn't rust, but I didn't trust it. Just my $0.02 worth.

Good luck with your new shop! Joe

adamsgt
01-18-2008, 05:24 PM
I've seen some "mist" systems advertised in some of the machinery catalogs. Have no idea how much liquid they spray or mist. Anybody use one of these and is it a good alternative to a flood coolant system?

Wayne Shaw
01-18-2008, 06:19 PM
For doing most barrel work, I don't think a coolant system is needed. If you want to use some type of chamber flush system, it is usually captured in a pan and returned back to the tank. It's a system of it's own, not a coolant system for the entire lathe.

BobB
01-18-2008, 11:46 PM
I use what is known as Kool Mist at work everyday.It's bascially a water alcohl mix that uses shop air pressure to produce a very fine mist. As the alcohol evaporates the workpiece is cooled considerably. The best part is, there in little to no mess as most of it evaporates. In some cases the piece can get cool enough that if you are keeping very close tolerances, such as in a bearing fit, you need to let the piece warm up to room temps. and normalize or your piece will be too tight.

You turn the valve on and it sprays out. The nozzle is adjustable for a mist that can barely be seen to a heavy spray, depending on what is required.

I've got a lathe at the house that I want to put a kit on. The kits cost around 100 bucks, but its well worth it.

J. Valentine
01-19-2008, 05:44 AM
Bobb , I have seen the mist systems for deep hole drilling and they are efficient systems but I feel that I dont like the fine vapour floating around and getting breathed in. Just my opinion.
Your Alcohol / water mist system is using " latent heat of evaporation " to cool.
Normal flood coolant has its own problems for sure and is messy especially on work close to the chuck and odd shapes and such.
I spent some time in a machine shop observing deephole drills and machining with Mist systems and I could not get close to the lathe before I felt uneasy with it. I may be all wrong on this but that is how I felt so I stay with what I like. I guess on a closed CNC it would be no problem.

Rustystud
01-21-2008, 10:04 PM
I use Rustlick 255R cut 5:1. in a 15 gallon barrel and a 3/4 hp gear head pump. I control my flow and pressure with two ball valves. I use a Duff Norton Rotary coupler to connect to my barrels. I have a 1." return line and catch my coolant in a bread pan. I have 3 earth magnets in the pan to catch the swarf.

Nat

msalm
01-22-2008, 10:06 AM
Thanks everyone for the comments. The shop is 40X40, well insulated and heated. Unfortunately it also serves other purposes such as extra storage for household items and such but there's plenty of room for my hobbies (so far!).

I've looked at those cool-mist systems too, and also the cold-shot air systems that don't use coolant. I know just holding a 90psi air gun over the work and cutter does wonders, and for the time being I may just stick to that. Tooling has eaten up most of what I had set aside to get started so now I'm looking at the last items on the list under closer scrutiny.
Still need an index head for my milling machine so I'll probably wait on the coolant.

Clark
02-12-2008, 11:11 PM
I mix Cool Mist at 10:1 or 15:1 by eye in a plastic house plant spray bottle.

I squirt coolant on the work with my left hand and turn the handles on the lathe or mill with my right hand.

It couldn't work any better.

I used to need a third hand to hold the magnifying glass, but then I got a head visor, and now I have the correct number of hands.

DannyH
02-13-2008, 07:08 AM
Clark,
You da man!!
Ditto

ShelleyDavidson
02-13-2008, 08:37 AM
High Sulfur Cutting Oil in my 16X40 Victor's flood coolant sump. It does a good job, doesn't rust or stink from bacteria growth. My lathe holds five gallons in the sump. Most of the time, I don't use the flood system, I just brush on a bit of cutting oil, but for some of the stuff I do, I put up with the mess and turn on the oil. When I drill and bore a 2" bar of stainless to an inside diameter of 1.375", I'm really glad to have the capability of flooding.

The flood system does get messy at times and high sulfur cutting oil does have an odor but it's an acceptable odor, in my opinion.

I do have a flush system for chambering but I no longer use it. I now drill and then taper bore till the hole is darn near chamber size so a spurt of the cutting oil and a reamer dip is sufficient.

Shelley

ShelleyDavidson
02-13-2008, 08:38 AM
High Sulfur Cutting Oil in my 16X40 Victor's flood coolant sump. It does a good job and doesn't rust or stink from bacteria growth. My lathe holds five gallons in the sump. Most of the time, I don't use the flood system, I just brush on a bit of cutting oil, but for some of the stuff I do, I put up with the mess and turn on the oil. When I drill and bore a 2" bar of stainless to an inside diameter of 1.375", I'm really glad to have the capability of flooding.

The flood system does get messy at times and high sulfur cutting oil does have an odor but it's an acceptable odor, in my opinion.

I do have a flush system for chambering but I no longer use it. I now drill and then taper bore till the hole is darn near chamber size so a spurt of the cutting oil and a reamer dip is sufficient.

Shelley

bill larson
02-13-2008, 10:37 AM
I chamber through headstock,when possible and use a thru-barrel flush stystem....I`ve done it the other way,applying oil by hand and the flush stystem is 100 times better...where are you located at.I have some extra tanks and pumps....

msalm
02-13-2008, 04:06 PM
Bill,
I'm close to the WI Dells, ever make it to that area along 90-94? I might be interested in a tank and pump unit if it would be handy.

Thanks,
Matt

Bnhpr
02-13-2008, 04:31 PM
See pic.

For turning diameters, and removing large amounts of metal, cooling extends the life of your tool, allows you to work faster, and get a better finish, with less chatter.

I use high sulphur cutting oil for threading, simply because you can still see with cutting oil, coolant blocks my view of the threading.

I put a cookie sheet under my lathe to catch the oil, so it does not contaminate the water based cutting fluid.

I put a cup of pine-sol in my water based cutting fluid to prevent bacterial growth.

Ben

SGS
02-14-2008, 08:48 PM
msalm,

Clark's suggestion of using diluted coolant in a plastic spray bottle has a lot of merit. It is inexpensive and effective. I work in a large facility with flood or mist coolant on most of our machines and I still keep a spray bottle handy for small lathe jobs, vertical mill jobs, or any time when I just need a little coolant and don't want the mess from the pump system. If you get used to doing this and you get a tank system later you will not stop reaching for the spray bottle.

For most of my gunsmith work on my lathe at home I use the spray bottle for external machining, brush applied cutting oil for threading, and lots of cutting oil for chambering. I will set up a through barrel pump system for chambering at some point because I have seen how much it speeds up the process of cutting a chamber.

There are many choices of water soluble coolants that work well. Some tend to contribute to corrosion if left on the surfaces of your machinery. Some are very corrosion inhibiting. Some will strip paint. The water based soluble oil based type is probably the safest.

Your shop looks nice and roomy.
Scott, Wisconsin native (Stevens Point) now in eastern NC

Dusty Stevens
02-15-2008, 12:47 AM
I use one of these:
http://www.vortexair.biz/Cooling/ColdAirGun/coldairgun.html

no more oil for me. this rig puts out frost.

http://www.vortexair.biz/Cooling/ColdAirGun/Cold_Air_Gun_2.jpg

msalm
02-15-2008, 10:52 AM
Dusty,
I've looked at those with interest and in fact that's what I've done in a sense recently while turning down a 6.5mm take-off barrel for an AR15 6.5 Grendel. I just used my air gun and blasted the bit and work with shop air while resting my hand on the toolpost. The chips immediately went from a continuous blue curl to bright small 'C's" and after several cuttig passes the barrel was still cold to the touch. Maybe just a coolant 'head' with shop air would be sufficient for the time being. Over $300 for those cold shot systems is a bit much for me right now...I still need to find a dividing head for the mill.

Dusty Stevens
02-15-2008, 02:56 PM
they have a vortex cooler in em that uses less air than just a nozzle and it cools the air to below freezing with just a little bit of air. a plain nozzle will run your compressor overtime. with the cost of inserts a vortex cooler will pay for itself very fast- according to how much you actually machine. the cool mist system works good as well for alot less money. I use an alcohol/ water mix and like was said before it will be evaporated before you can stop the mill. the cool mist works better on the mill and vortex works better on a lathe- as far as my use.