Milling machine coolant drains?

[Highpower]

Probably an odd guestion, but I need to ask because I have never personally seen a "proper" coolant system set up on a milling machine. My mill has 2 pipe plugs screwed into the rear of the table at each end, obviously for draining coolant/lubricant from the table when employing flood coolant on a mill. I'm just a hobbyist doing one offs so I don't require flood coolant, but I have been hogging a lot of material lately and even using my little spray bottle is filling up the table with solvent.

I'm just wondering what they use in production shops to hook up these drains to the sump in the machine base? It has to be some type of flexible hose that is water/oil/coolant resistant. The question is what material works for this?

 

[flutedchamber]

Shops usually use a 90* street el or a T with a rubber hose to the base to drain coolant back. I worked on two Bridgeports with a coolant system. Messy is an understatement. Small chips will clog the hose or fittings, which is why most shops use a T fitting ... so you can clean the hose out from the top.

 

[Highpower]

I see. That is a good point about using a T in the line. But I'm wondering what KIND of rubber hose is used that won't swell up and get soft from contact with oils / coolants?

 

[Tony Wells]

Well, cost aside, Viton is impervious to most common solvents, but you might do better finding some Teflon. I use the stainless braided supply line like you'd see supplying a kitchen sink for my coolant supply. Of course, the normal size for that would likely be too small for a drain, but there may be something larger available. Lowe's has a selection of various hoses in bulk, so you could do a little experimentation. Just avoid natural rubber in favor of a synthetic.

And a piece of screen across the drain opening will help keep the drain clear.

 

[flutedchamber]

I see. That is a good point about using a T in the line. But I'm wondering what KIND of rubber hose is used that won't swell up and get soft from contact with oils / coolants?

The two machines I ran used hydraulic low pressure return lines..something like 1/2 or 3/4 inch. It was plenty flexible and no issues with the coolant. The hydraulic return lines don't use a steel braid...just some type of nylon or such.

 

[Davo J]

I replied to this thread just after you posted and before the forum change, but it seems it was lost and I have only just been able to log in again.
So here I go again, LOL

Most mills seem to come with steel or brass 90 degree fitting(s) on the table that have tapered pipe threads. Mine is 1/2 pipe thread and most Chinese machines seem the same. I have some plastic pipe fitting here from the local hardware that I am going to use on mine instead as they are a nice flowing bend that wont get clogged like the sharp 90 degree ones that come on it.

As for coolant hose they all seem to be coming with fuel type hose these days. It is the same as in the link below, but in 3/4 (19mm) size not the 10mm advertised.
http://www.bcf.com.au/online-store/...od-Fuel-Hose-10mm.aspx?pid=118288#Description

I picked some up over here and from memory it was around $60 for 20 meters from the local wholesaler. The local hardware wanted some ridiculous price for it.

Dave

 

[brucer]

the bridgeports and prototraks i ran years ago that had coolant systems on them, on the ends of the tables where the drains were they had a filter material laid in them then had stainless mesh laid over the top of the filter material.. you had to pull them up to clean the debris out of them periodically..

i would think a scotchbrite pad cut to fit with some expanded metal, or stainless mesh would work fine..

they all had catch trays on the base of the mills also...

 

[Davo J]

Good idea, another one is to throw a magnet in a plastic zip type bag in the coolant tank. When it gets full turn the bag inside out and throw it away.

On my bandsaw I have round speaker magnets (with the hole in the centre) one over the drain and also one down further in a funnel going into the coolant tank to help catch swarf. For catching aluminum and plastic bits when I cut it, I have some fly wire in the funnel. I just cut a circle out and put it in the top of the funnel, and to clean it I just shake it over the bin.

Dave

 

[brucer]

also rural king or tractor supply company will have the tubing in the agriculture/sprayer section.

you could use a rubbermaid type storage bin for a tank they are like $5, and use one of the harbor freight cheapie fountain pumps for like $15..

 

[Highpower]

As for coolant hose they all seem to be coming with fuel type hose these days. It is the same as in the link below, but in 3/4 (19mm) size not the 10mm advertised.
http://www.bcf.com.au/online-store/...od-Fuel-Hose-10mm.aspx?pid=118288#Description

Dave

I actually have some of that hose here. I hate it.

I bought it to use for the drain on the icemaker (commercial unit) in our kitchen. I have both types of the hose.
1) Too stiff.
2) Too soft.

Depending on the wall thickness, it either collapses way too easily and blocks the line, or it's too stiff and not not flexible enough causing other problems with the hose routing or breaking fittings from tension. I guess I'll just have to do some searching for some type of synthetic hose that has good flexibility as Tony suggested.

Again, even though the machine already has a catch basin and a place for a pump in the base - I'm not wanting to set it up to use the flood coolant system. I don't want to deal with the mess in by basement shop. I just want to let the table drain off what I'm applying from a spray bottle into a couple of buckets on the floor for disposal. Sucking it up with a wet vac or soaking it up with rags is getting old - fast, as is spilling it on the floor and turning it into a sheet of ice.
"Slip, slide'n away"...

Thanks too, for the tips on screening/filtering the drains. I do have magnets on my band saw drains for catching steel but that doesn't do any good for aluminum of course. I like the idea of using a scotch-brite pad for a filter! I'll have to do that.