Hi, Jason with Tormach. Let's talk about mold machining. We have our 1100M all
set up to machine a mold for a carbon fiber layup. This mold will be used to
make custom intake tubes for Corvettes. This is a large part, we started with a
18 by 8 inch by 6 inch block of aluminum, that weighed about 87 pounds. The 1100 M
has 18-inch of travel in X, so we definitely needed all the machine to be
able to make this part successfully. So let's talk about how we managed the part
size, and the finishing strategies to be used while we were cutting this mold. So
here you can see the block of material. It's sitting on the scale at 87 point 2
pounds. We loaded this thing up in the 1100M. Mounted it on a fixture plate
using the modular clamps, and then we loaded up this new 1 inch mini shear,
from AB tools. This is a three flute roughing tool from AB tools that's
designed for cutting aluminum. So we wanted to put this thing through some
testing here with this big part. We actually ran this tool in this roughing
strategy. It was a little over three hours total. There's a lot of material to
remove on this side of the part. So we went ahead, and worked through it. We ran
this thing at..it ended being right about 1,300 surface footage, at 5,000 rpm and a
five thousand and five tenths chip load which worked out to about 83 inches a minute
we were taking about 300,000 steps to cut and a 125,000 step over. And you'll
notice, we use a both ways adaptive roughing strategy on this. It saved a
tremendous amount of cycle time on this part, just being able to cut both ways,
and literally cut cycle time in half on this one. On that strategy, we went ahead
and we lighten up the width of cut, but we kept the feed rate the same. So our
width of cut, we turned down to about a hundred thousandths on the conventional
side, but we left the feed rate, and everything the same. We tried to lean on
it to get some efficiency out of it. We also wanted it to be, you know, safe and
have a lot of process reliability with this tool path. I didn't want to
stand in front of the machine and watch it rough for over three hours. So we got it
running...was happy with how it was cutting, and we walked away, and we just
let the camera run, and let the part finish roughing. We did have a fine step
down on this parts. So we had a 300,000 step to cut but our fine step-down was at
fifty thousands of an inch. So you'll see we get the nice smaller
scallops on this, so we can come back and do those semi finishing, and stuff a
little bit easier. We'll go ahead and let some of the roughing footage and stuff
play. As I mentioned earlier one of the challenges of this was, the parts the same
size as the machine travel. So we had an 18-inch part on 18 inches to travel to a
pathing was a little bit interesting because we had to contain that tool path
in the x-axis, but we had enough travel in Y, to be able to run the tool off the
side, and everything so we had to create some boundaries on the side of the part.
We just drew a couple...basically big rectangles on the side to keep the tool
path out of that area, and that ended up working really well for us. It as
you can see as this cutting and stuff it worked through and it actually started
in the center of the part. Ideally we would have liked to start on the outside
of the block, but just to get this to work and get the tool best to layout
correctly that's where it ended up starting for us the machine, and
everything handled just fine. Ramping into the part you know, I would have
liked to been able to play with it a little more. Let's start on the outside but
sometimes you you know if it's working you just kind of let it run just to keep
everything moving. Once we got done with the one inch roughing tool, we came back
with a half inch diameter mini shear. This is a single flute cutter that uses
the same insert as that larger one-inch but we're able to go all the way down to
a half inch diameter with this, but we were able to run this tool at 7500 RPM,
at five thousand, three tenths per tooth chip load, and it's a single flute so
that worked out to about forty inches a minute.
And we ran this at a hundred thousand depth of cut again and a fifty thousands
width of cut. And then we just went ahead and did a rest roughing tool path on this
to pick out that bottom area. But not re-machine everything that we already
had done. Once we wrapped up with that half inch diameter mini shear then we
jumped over to our 16 millimeter ball end mill.
This is an inserted ball end mill, as you can see. We had to do a quick
restaurant routine with this one as well to go ahead and clean out the big
radiuses in the bottom of that pocket a little bit. There's actually a full
radius that runs right down the edge of the part so we needed that ball end mill
to be able to put that in so we came back with this quick. It did another
rest roughing routine again with an adaptive roughing strategy.We're able to
run this to what five thousand RPM, at about fifty inches a minute. For roughing
our depth to cut on this again, one a hundred thousands of an inch, and the
width cut we set at one hundred and ninety thousand.Once we got those little
pockets cleaned out then we were able to come back and start semi finishing. One
of the important processes when you're machining a mold is to...when you're
actually going for your final finishing passes you want a real consistent amount
of material on the parts, that the tool load is consistent, and then it just
really helps you improve your surface finishes. So we came back we did some
semi finishing.One of the debates is always what tool past strategy is gonna
work best for my part should I do a raster, where I just run
back and forth, should I do like a 3D offset style, where it takes the profile
and collapses down onto it. You know there's a lot of variables there what is
my machine like what is this part geometry like and all that stuff really
comes in effect of it it's always coming those things you argue with yourself
about while you're programming the part some are you know kind and they lend
themselves really obviously to what strategy is gonna work out well for him
but some of them you know you could kind of go back and forth on what you want I
kind of cheated on this part I ran it both ways I did a couple test cuts so I
actually left some extra stock on my roughing and then as I semi finished it
down I started at 50 thousandths of an inch material on my rough stock so then
I could semi finish that a couple times I wanted to be able to see what kind of
depths of cut the Machine and the tool liked you know to get a good surface
finish when you're laying up carbon fiber really any mold work at all the
surface finish the ball is extremely important any little tooling mark any
little imperfections gonna show through in the final product so I just wanted to
give myself the best chance to success I could so I went ahead and essentially
finished the part a couple times as you can see the first time I did the semi
finishing strategy I used the fog buster this worked and it kept the chips clear
I did see some recutting I did see a little galling on the surfaces of the
part itself that it wasn't clearing the chips effectively and it was recalling
them as we were doing the finishing so after that I did go ahead and I switch
to the flood coolant setup just to help flush those chips away and get a better
surface finish on the part so you can see I kind of finished a couple ways I
did a couple raster passes that are just the straight back and forth I ran a
couple of amount of 45-degree angle with a perpendicular pass I really just tried
to play around with this and see what what laid out
vast so we ended up finding out is that on the mold cavity itself the 3d offset
style or a scalloped style toolpath gave us a really nice finish on the walls and
everything it did have one little feature on it that I didn't care for
which it ended up leading a line right down the center of the mold where the
tool would change directions it's a real faint line and stuff you can definitely
see it in the part but it is there but when we ran the finish pass as a raster
style tool path it just didn't come out as smooth as the curves everything in
the walls of the part didn't look as nice you know the customers essentially
was happy with that line being in the part to get a better surface finish on
the outside so as I mentioned we end up using it that scalloped tool path for
the finishing and that 16 millimeter ball end mil again we're able to run
that a little bit faster on the finishing we ran that at 7500 rpm had 50
inches a minute on our finishing strategies for the mold cavity itself we
ran a step over of 5 thousandths of an inch and when we finished the parting
surface on that we did use that raster style tool path again and we tighten up
the step we'll run that to two and a half thousands so here's the mold all
finished up pretty happy with Outlook you can see that little window sliding
down the center of the part but all in all that part looked really nice we're
pretty happy with how it looks but as you can see the whole back side of this
thing we didn't really show the footage of it in this video but the whole back
side of this part is scalloped out you can see a little bit here at the end
when we're flipping it around but so this mold ended up weighing about
thirteen and a half pounds it was definitely a fun project to take 75
pounds of material off of this thing and have a nice looking functional mold when
we're done is definitely a lot of fun you know we took over 70 pounds of chips
off this mold and it looks great when we're done we have a nice functional
part so thanks for watching I hope you guys enjoyed the video for more
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