Re: [CAD_CAM_EDM_DRO] Any "Best Practice" Recommendations for clearing chips and feed/speed whencutting Aluminum??
Posted by
Jon Elson
on 2001-12-23 23:29:53 UTC
glee@... wrote:
the small amount of propane that you release with each squirt of WD40,
you are very unlikely to create a flammable mixture. However, the results
of that would certainly spoil your day. It would most likely not be a flame
thrower, but a detonation!
thread cutting oil when I don't want to incur the mess of my flood coolant
system. That uses a jet of water-based coolant and tool lube to clear the
chips and keep the tool and workpiece cool. When doing extensive work
in a small area on aluminum parts, the workpiece heats up. A slurry of
WD40 and chips is a lot better than a slurry of metled aluminum stuck
to the end mill. Someday, you will experience one of these, and it will
wreck your cutter in a couple of seconds.
their first service and use them for other jobs. They are also less hazardous
that the metal-handled brushes. I used to think they were safe until I
has one pass through the cutter, get wrapped around the cutter and spindle
and then be thrown across the room!
mist coolant or just air might also be useful.
they mix up with lard, milk, etc.
This works out to about 18000 RPM for a 1/8" cutter! Chip loads should be
about .001" per tooth. For a 2-flute end mill at 2500 RPM, that works out to
5 IPM. If you can get more RPM, increase feed rates accordingly. These would
be for roughing cuts of about .062" width and .062" deep. If you are plowing
the full width of the cutter, either reduce the depth or the feed rate. When
the
walls of the cut look wavy, that is proof of tool deflection, and that
indicates the
tool is under severe loads, so back off on the feedrate.
Jon
> Well, tonight I switched from cutting wood to machining 6061 aluminum withYes, it is a concern. Probably, with the amount of air a shop vac moves, and
> my Sherline Mill using a 1/8" end Mill to Mill a part 1" x 1.6" by .25"
>
> It was an education to say the least. In the process of documenting the
> results, I arrived at some questions:
>
> When I was practicing on plastic and wood, I ran the ShopVac with the
> intake nozzle next to the cutter. This way, it was a superbly clean
> process.
>
> When cutting aluminum, I used WD40 From time to time to lubricate the
> cutter. I noticed that the WD40 label says "Highly Flammable - propane." I
> decided that I would not use the ShopVac and the WD40 at the same time for
> fear of starting a fire inside my ShopVac and making my ShopVac a flame
> throwing jet engine. (Am I correct in this concern)
the small amount of propane that you release with each squirt of WD40,
you are very unlikely to create a flammable mixture. However, the results
of that would certainly spoil your day. It would most likely not be a flame
thrower, but a detonation!
> Since I was no longer using the ShopVac I now had a micro chip problem.WD40 is a poor substitute for a proper cutting lube. I use hardware store
> This was further complicated by the WD40 (used in moderation) and resulted
> in an aluminum "Slurry" surrounding the cutter and resting on top of the
> part.
thread cutting oil when I don't want to incur the mess of my flood coolant
system. That uses a jet of water-based coolant and tool lube to clear the
chips and keep the tool and workpiece cool. When doing extensive work
in a small area on aluminum parts, the workpiece heats up. A slurry of
WD40 and chips is a lot better than a slurry of metled aluminum stuck
to the end mill. Someday, you will experience one of these, and it will
wreck your cutter in a couple of seconds.
> No problem, I thought. I used an acid brush to brush away the debris -Toothbrushes seem to work even better. I collect the ones retired from
> still wishing I could run my ShopVac.
their first service and use them for other jobs. They are also less hazardous
that the metal-handled brushes. I used to think they were safe until I
has one pass through the cutter, get wrapped around the cutter and spindle
and then be thrown across the room!
> Well, combine the above with the lessons I learned about climb vsFlood coolant is the best, in my opinion. If you have an air compressor,
> conventional milling as well as and feed/speed rates, I have probably
> broken many rules tonight not to mention possibly destroying my cutter. At
> least I am learning and having fun while making chips.
>
> So, now that I have shared the gory details, I will ask for
> feedback/correction:
>
> 1. Any ideas on the removal of chips
mist coolant or just air might also be useful.
> 2. Any ideas on the lubrication of the cutter (It's an 1/8" end mill)Cutting oil, thread cutting oil, some people swear by ATF and other things
they mix up with lard, milk, etc.
> 3. I experimented with feed rates and speeds as I was encouraged to do. IWith HSS tools on Aluminum, surface speeds of 600 IPM and up are recommended.
> came up with 2500 rpm, 5-10" ipm on XY and 1 ipm on Z seemed to work. I
> would welcome some recommended rates for my sample part
>
> Spindle Speed?
> Feed Rate XY?
> Feed Rate Z?
This works out to about 18000 RPM for a 1/8" cutter! Chip loads should be
about .001" per tooth. For a 2-flute end mill at 2500 RPM, that works out to
5 IPM. If you can get more RPM, increase feed rates accordingly. These would
be for roughing cuts of about .062" width and .062" deep. If you are plowing
the full width of the cutter, either reduce the depth or the feed rate. When
the
walls of the cut look wavy, that is proof of tool deflection, and that
indicates the
tool is under severe loads, so back off on the feedrate.
Jon