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Gasgasbones
22-11-2014, 09:48 AM
Hi

I'm looking for a simple solution to keeping the tooling cool on a VMC190.

I was was thinking a small aquatic air pump would work as I'll only be making small parts, mainly from aluminium and brass etc. This would blow the swarf away too.

But, you're the experts. What other ideas or solutions have you used ??

I haven't got the room really for a larger compressor and i realy don't want to start using liquids.

cheers guys

Carl

m_c
22-11-2014, 12:52 PM
For aluminium, you'll need liquid of some kind, otherwise it's likely to stick and cause you big problems.
However that liquid can be as simple as a little spray of WD40 occasionally, combined with just enough air flow to blow the chips away. All you need to aim for, is to keep the cutter coated with oil, and get the chips away from the cutting edge so they don't get recut.
You don't need a large compressor, however I'd doubt if an aquatic pump will have enough flow/pressure to clear chips, especially if it involves blowing them out a recess/pocket.
.
My suggestion would be to beg/borrow/steal a compressor of someone, so you can get an idea of what you're requirements would be.

JohnHaine
22-11-2014, 02:23 PM
The trouble is that you need some lube to stop the chips welding on the tool but that makes the chips into a slurry that won't blow away unless you have a lot of air and that blows some of the chips all over the place! I don't have a good solution to this unless you use flood cooling. With some grades of Ali the chips don't stick if the tool runs fast and you can easily blow the chips away. By the way the edge of the tool needs to get hot, the need is not to cool it but stop the dwarf welding on.

cropwell
22-11-2014, 05:10 PM
Hi Carl,

Have a look at eBay, the pond air pumps by Hailea pumping 140 litres per min at low pressure for about £50. I use an 80 litre one on my small machine and it is OK. I also have the Lidl airbrush compressor with a blow nozzle. That can clear build ups, but hasn't got that much oomph. You could also use the airbrush from the kit to blow a spray on the work.

It is a quieter solution than a 2hp compressor, but a little on the gentle side, rather than industrial.

I have a small A4 gantry machine and a cheapskate attitude - but the pond pump works for me !

Cheers

Rob

Jonathan
22-11-2014, 08:00 PM
The other big advantage of not cutting dry is that coolant or oil lower the coefficient of friction between the tool and material, so less heat is generated to start with. That's partly why even a small amount of 'something wet' can make a big difference.

Gasgasbones
22-11-2014, 08:12 PM
Cheers fellas.

I use WD40 on my manual mill but after a while it leaves a sludgy swarfy mess in the T grooves which are a pain to clean. I wanted to avoid this on CNC if poss so hoped air would help.

I have a large compressor but its in shed 2 and shed 1 with the CNC won't fit it in :-)
I'll try a combination of the small air supply and WD40 and see how I get on.

cheers fellas,

carl

JohnHaine
22-11-2014, 11:45 PM
An alternative to wd40 which I find is a little hard to control is a mixture of cutting oil and paraffin applied with a brush. Also cheaper!

magicniner
24-11-2014, 01:18 PM
I use a refrigeration compressor on the receiver, plumbing and electrics from a portable compressor with a failed motor/compressor unit.
I formed a nozzle in the end of a short length of copper brake pipe by crimping the end in a 3-jaw chuck with piano wire up it to keep a small path open.
When I want lube in addition to chip clearance I add a drip-oiler with 70/30 Parafin/Oil directed onto the outside of the copper pipe a couple of inches up from the nozzle, the resulting coarse droplet mist doesn't travel and doesn't cause slurry or stop chip clearance,

- Nick