RV antifreeze works well for things like this. I have been using it for
years in my bandsaw coolant tank. It doesn't seem to go bad even after
years and it doesn't evaporate much.
For cooling, You might want to consider making a flat tank. Two sheets
of steel or alum spaced apart an inch or so and welded at the edges.
That would increase your surface area for cooling while not creating a
huge tank volume wise. Put the tank on edge and it won't take up much
space.
On 5/22/2018 5:34 PM, Bruce Layne wrote:
I've had two of the Chinese 2.2 KW water cooled spindles for the last
few years and have had no trouble with them. I consider them to be a
good value. Well worth the plumbing hassle, in my opinion.
Be sure to use good quality very flexible tubing of the correct size.
I think I got 8mm outside diameter tubing from McMaster-Carr (red for
supply and blue for return). I use pink RV antifreeze as the
coolant. It's used full strength and not diluted. I use it in the
hope that it's less corrosive than water. Neither machine's coolant
has had any rust or other issues, although there was a slight film of
oil that's flushed out of the spindle motor. I'm not worried about it
freezing because one of the CNC routers is in an attached garage and
the other is in my basement, and neither get very cold. I'd actually
be more worried about the machine rusting if it was in a condensing
environment, and the CNC routers are mostly aluminum.
I mounted a thin liquid crystal thermometer on the spindle facing the
operator so I can tell at a glance if the spindle overheats. These
liquid crystal strip thermometers are readily available on eBay and
are sold for reptile terrariums. I buy a bunch of them and put them
in electrical panels, etc.
I haven't finished wiring it yet, but the production machine will have
a 130F bimetallic button thermal switch siliconed to the spindle motor
housing and wired into the e-stop circuit to shut everything down if
the spindle overheats.
The Huanyang VFD produces a lot of electrical noise, apparently mostly
radiated. I used ultra flexible shielded four conductor cable (three
phases plus ground) to keep the cable from radiating much energy. The
only place I had an RFI problem was the VGA monitor and a good quality
VGA cable fixed that problem.
On the larger router, I tried to place a five gallon coolant tank
under the router and pump the coolant up and then back down to the
spindle motor. I was partly motivated by not wanting a leak that
siphoned the five gallon coolant tank empty. After some
experimentation, I gave up and put the coolant tank on top of the CNC
router enclosure. When it was underneath, I needed to use such a
large pump to have enough pressure to pump the coolant six feet
vertically that the submerged coolant pump was heating the coolant
more than the spindle. It was a spindle heater, not a spindle cooler.
We're finally ramping up production, with some programs running
unattended for ten hours. I'm going to need to add a radiator in the
coolant return line and a couple of muffin fans to keep the coolant
temperature low enough. The other alternative might be ten or fifteen
more gallons of coolant to increase the thermal mass, but that seems
to only delay the overheating problem with greater risk of a severe
coolant leak.
On 05/22/2018 03:18 PM, Roland Jollivet wrote:
I'm looking at getting one of those 2.2kW air or water cooled spindles +
VFD kits out there for a router.
I'm not worried about the noise difference between the two types.
Has anyone taken apart a water cooled spindle?
How are they doing the cooling? Is it a water jacket or just some copper
tubing inside?
How likely is it to leak in a few months time?
I can only find one video describing leaks and water related shorts etc.
(so they must be good?)
I actually prefer the idea of using air-cooled and making ducting to
take
the exhaust away from the spindle nose. Make a closed loop
fan-assisted air
duct.
The irony is that I want to use flood cooling on the work. (composite
material) So it won't be a dry environment.
Regards
Roland
------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
_______________________________________________
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users
------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
_______________________________________________
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users
------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
_______________________________________________
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users
