Milling machine coolant system

Hi chaps. I mill a lot of aluminium and coolant is a big issue along with chip clearance. I started with a coolant spray bottle, ok for milling face cuts and open sides, but useless at slots or pockets. I then went to a fog buster set up and had little improvement over the bottle. Added pressurised air to the fog buster to help clear chips, worked ok but still found at times during deep cuts the chips not clearing and welding to the cutter taking place. So now I am looking at flood coolant. I have seen the warco sort of set ups, but don’t feel that they give enough coolant flow after watching a few videos on utube. I have read the posts on this site, but it’s mainly lathes. So what do you chaps use for aluminium milling deep slots etc.thanks

There was a discussion about coolant yesterday, here on MEW, plus lots of other posts about coolant systems. The same flood coolant system for lathes can be used on a mill.

I use a commercial tank and pump. Available from most lathe/mill equipment suppliers amd on ebay. Ample coolant supply to overflow the table if not throttled back.  The tank has 2 compartments. Coolant return passes thru a strainer into the first compartment, then flows over a wall into the second to separate any swarf.

Paul

Universal Coolant Fluid Pump

• 240v Single Phase
• Flow Control Lever
• Magnetic Base Adjustable Nozzle
• Push Button Control
• 3 Pin Plug

Dimensions

• 11 Litre Tank
• 37 x 26 x 17cm
• IP54 Switch-plug combination
• Delivery Height 2.5m
• Delivery volume 3.5 Litres per minute
• 100w 240v Single Phase Pump
• Adjustable Flow Control Hose

Edited By Paul Lousick on 31/08/2021 13:01:04

The coolant will do three jobs.

Lubricate the cut

Cool the tool and the workpiece.

Was away the swarf.. ( Ali does tend to weld itself to the tool because of the heat generated )

Paraffin (Kerosene) is a good lubricant for machining Aluminium, but don't smoke near it or inle the fumes..

Howard

Edited By Howard Lewis on 31/08/2021 12:58:41

Hi Paul, what sort of flow rate is the pump. I have found by using a friends mill that the flow was too low and the coolant ended up all over the place as the cutter was able to throw it from the cut. I was looking at getting a heavy flow of coolant to stop the cutter being able to throw it away from the cut and all around the workshop. But still not sure which pump would be best.

I use a 1/4 hp suds pump and flow rate is not a problem.

I return the suds to the tank via a filter bag designed for straining carp pooh out of a koi pond.

That keeps the flow restriction tap clear.

Hi, Terry not sure where you are based but I have a bijur unit that used to be fitted to a bridgeport it's missing a few parts but could be got working it's clean I am in Nottingham. An alternative may be to use a higher pressure pump rather than the centrifugal high flow low pressure pump you have. The sort of thing that most fuel injection systems use to run petrol from the tank to the injectors. Or a middle ground might to use a std electric petrol pump for a carb engine these can give a combination of flow and pressure. The flow might be a little pulsed but adding a damper vessel might help there. Alternatively there are chemical dosing pumps out there that can give much higher pressure I bought 3 cheaply to use myself but have never got round to testing them out. In all these situations getting a clean return flow into the pump is critical so that needs to be given some thought that's one are where the centrifugal pumps are advantageous and have dominated the market?

Barry

You have to take the amount of enclosure the machine has. A cnc machine uses high pressure coolant, any thing up to 1000’s psi, and these are fully enclosed, any other type of enclosure will limit your pressure and flow unless you work ina wet suit with breathing gear. For aluminium you are probably better stick with air to blow the chips clear and a small amount of lubricant directed to the cutting edge. Another way is to create a cold atmosphere at the cutting edge which will break the chips earlier stopping edge weld.