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Moldmaster

Plastic
Joined
Nov 20, 2020
Hello everyone. Im a mold/parts manufacturer, looking for a new ,value for money machine.
My best candidates are:
Doosan DNM 5700
Hyunday KF5600
YCM NSV106AMS

All of them include mold package

what do you think?
 
Interested to hear about the YCM. I am looking at the NVS106AMS with a Siemens controller pretty hard.

What benefits do you get from the Siemens? I heard they're better on 5 axis ,but on 3/4 axis? I think fanuc is cheaper and more reliable
 
Hello everyone. Im a mold/parts manufacturer, looking for a new ,value for money machine.
My best candidates are:
Doosan DNM 5700
Hyunday KF5600
YCM NSV106AMS

All of them include mold package

what do you think?
I recently saw a vertical at a show that used Akribis linear motors. Damn. Pretty cool, fast and quiet. Not that that's a huge factor but found it interesting.

I could find out more but dunno, the usual "gotta be crap, made in China ..." stuff.

Anyhoo, if'n I wuz looking at new vmc's, I'd take a look at this one, fer shure. Linear motors are neat, and they come with linear scales, too (obviously).
 
I live in Israel. This company doesn't have any representatives here. Doosan, haas ,okuma and mazak have the largest agencies.
 
My understanding is that due to heating associated with linear drives, thermal management is a big deal with machines using them. I'd want a lot of assurance that thermal control is not only designed-in, but robust and reliable.
 
My understanding is that due to heating associated with linear drives, thermal management is a big deal with machines using them. I'd want a lot of assurance that thermal control is not only designed-in, but robust and reliable.
I've heard similar things about ballscrews and high speeds :D

If I were going to buy a vmc, I'd look at these seriously. In action, it was kind of impressive.
 
Die and mold work is usually about accuracy and surface finish, not speed. Look at a Yasda's specs and you will see many of their die and mold machines have a max feed rate of around 200 ipm
DMG is pushing linear motor machines pretty heavily, for mold work as well as other high-precision stuff (linear motor machines have to have scales as well, no way to put an encoder on a screw.)

I dunno about that speed thing, 'plates ... we had two OKK's doing wheel molds, they zipped around okay but to me 200 ipm feeds is fast :)

View attachment 305363

Anyway, I think it's an interesting technology worth looking at. Been around long enough to get past the "crazy invention" stage, I know a few gear grinders actually use linear motors for the tables, and DMG here is peddling them for mills ...

Different place but the video is kind of a fun watch

G series, 5 axis high speed linear motor gantry machining center, APEC - YouTube
 
DMG is pushing linear motor machines pretty heavily, for mold work as well as other high-precision stuff (linear motor machines have to have scales as well, no way to put an encoder on a screw.)

I dunno about that speed thing, 'plates ... we had two OKK's doing wheel molds, they zipped around okay but to me 200 ipm feeds is fast :)

View attachment 305363

Anyway, I think it's an interesting technology worth looking at. Been around long enough to get past the "crazy invention" stage, I know a few gear grinders actually use linear motors for the tables, and DMG here is peddling them for mills ...

Different place but the video is kind of a fun watch

G series, 5 axis high speed linear motor gantry machining center, APEC - YouTube

I don't deny they are interesting but I would not say they meet the OP's requirement of a "value for money machine"

What little I know about them is they can be super fast but require MASSIVE amounts of current to hold the table stationary or in position when heavily loaded by the tool.

Personally I rather an older well proven and refined accroach like scales and fine pitch screws and let someone else deal with the inevitable growing pains of linear motors. JMO

BTW nice mold, I love seeing work like that
 
I don't deny they are interesting but I would not say they meet the OP's requirement of a "value for money machine"
The DMG ones I betcher right, but the show machine I saw, maybe. Have to go find it again, see how much. It was a double-column vertical, like a Hillyer, just cutting aluminum at the show but looked good. The quietness was really surprising. Did I say that yet ? It's surprising how much of the noise of machining is actually the screws.

Personally I rather an older well proven and refined accroach like scales and fine pitch screws and let someone else deal with the inevitable growing pains of linear motors. JMO
From the money side, you're right. From the interesting side, hey ! what fun is that ? Most of the stuff I've owned, I shouldn't have ....

BTW nice mold, I love seeing work like that
Thank you. Here's the rest, fun to watch in operation.

View attachment 305366

It's a low vacuum counter-cast method, liquid aluminum poured into a pond that drains out the bottom, over to the bottom of the mold then up. Bottom core, top core and four side cores (they call them cores, I don't know why, they aren't ?). They'll fill the wheel, wait a minute to solidify, then top core goes up and four side cores slide out on those guides and hardened ways by air. Roughly fifteen grand for a wheel mold, in case you want to go into the biz. Hot wheel removed manually. Anything hot, dangerous and noisy is cool.

Maybe that's why I'm stuck with this Assistant ...
 
At risk of dragging the OP's thread further off topic.....

Linear motors have some real attractive characteristics for machine tool use. At the same time they have unique challenges to be faced when using them in that application. Hardplates has noted one with his comment about energy use being very high. Milland noted another in the heat generated by the large amount of energy used. Compared to energy usage and heat generated in a ballscrew driven system, I've heard some folks say as much as 10X for a linear motor to have the same design stiffness.

Another very overlooked factor that was pointed out in a discussion with some Makino folks was that the guide ways used in a linear motor machine had to be sized not only for the mechanical load carried, they also had to carry the substantial electromagnetic load of the linear motor. This requires substantially oversized guideways compared to an equivalent ballscrew driven design. The oversized guides then created their own issues with increased stiction for the position loop to deal with.

As with all things machine tool related it's a game of managing compromises.
 

Maybe I'm just an old silly-billy, but at 1:25 in that video I see Y and Z driven by ballscrews, not linear motors. Can't see X from that view, but I doubt they'd use linear just for the one axis.

Also, I doubt that 2-axis head is linear, so either someone used the wrong illustration or it's not a linear motor machine.
 
Maybe I'm just an old silly-billy, but at 1:25 in that video I see Y and Z driven by ballscrews, not linear motors. Can't see X from that view, but I doubt they'd use linear just for the one axis.
OPTIONS, Mill. Watch more careful. They offer both ways. And show both. Altho that video emphasizes the wire guides as much as the motors ... marketing dept :(

I'm starting to worry about you guys.

Also, I doubt that 2-axis head is linear, so either someone used the wrong illustration or it's not a linear motor machine.
No, they described the construction of the fifth axis with two ballscrews, one on each side, and now I'm really concerned. I only watched the thing once, quickly ... (turns out this one is a Taiwan company, didn't want to discredit myself with the anti-commonists here. Pretty similar to China-built stuff tho, even the factory looks the same.)

Quit throwing spitballs and pay attention back there !

btw, they could have made the B (is it B on a vertical ?) axis linear, Akribis makes radial linears and Pfauter or Hofler or one a them Chermans is using them for the tables in gear grinders. But no, this one isn't. No real advantage to it, I think.

Didn't someone make a mill with an nc rotary table that would spin to 2,000 or so, so you could use it as a lathe as well ?
 
.......Can't see X from that view, but I doubt they'd use linear just for the one axis.......

I didn't watch the video so no idea what the machine it shows is like.... Some machine configurations lend themselves to having one axis use linear motors while the rest use ballscrews. Most commonly, machines designed for long airframe components. A machine with say 4 meters of travel in one axis while the rest are more "normal sized", really benefits from a linear motor system on the long axis. Long screws are hard to rotate fast without whipping/oscillation issues. One solution is to fix the screw and rotate the nut, but that is not without compromises too. There is at least one company that makes integral ballnut servo motors though to overcome a major issue when designing a rotating nut application.
 
I'm starting to worry about you guys.

I'm well past worry and fully into screaming hysterically mode.

No, they described the construction of the fifth axis with two ballscrews, one on each side, and now I'm really concerned.

I think they confused the Z (which uses two ballscrews) with the rotary head.

btw, they could have made the B (is it B on a vertical ?)

Z axis rotary would be C, but that leads to my confusion on A and B. If you've got full 360 rotation on C, do you define the remaining axis as A or B? Is it just dependent on how they set up the "Home" orientation?

Didn't someone make a mill with an nc rotary table that would spin to 2,000 or so, so you could use it as a lathe as well ?

Brother makes a small, high rotary speed machine, I don't know who does larger versions.
 
I didn't watch the video so no idea what the machine it shows is like.... Some machine configurations lend themselves to having one axis use linear motors while the rest use ballscrews. Most commonly, machines designed for long airframe components. A machine with say 4 meters of travel in one axis while the rest are more "normal sized", really benefits from a linear motor system on the long axis. Long screws are hard to rotate fast without whipping/oscillation issues. One solution is to fix the screw and rotate the nut, but that is not without compromises too. There is at least one company that makes integral ballnut servo motors though to overcome a major issue when designing a rotating nut application.

We used to use linear motors when we needed really fast motion. Because of the issues with long ballscrews, our longer axes were usually double-servo rack and pinion with countertorque, but when we started needing higher speed, they went to linear motors, especially on axes where their more compact nature was useful. A rack and double pinion setup isn't small.

Vertical linear motor driven axes are interesting. Servo-motors spend a fair amount of their energy overcoming friction, and have a mechanical advantage, so sizing the motor to deal with gravity load is often easier than having a counterbalance. With a linear motor, you are power/cooling limited, so decreasing the holding force makes a counterbalance often well worth the complexity.

With a servo-driven ballscrew, safety is easy. You buy a servomotor with a fail-safe brake on it. Depending on the type of coupling and how safety critical it is, you may also stick a fail-safe brake (usually pneumatic) on the far end of the screw and add a safety nut. Because of the mechanical advantage of the screw, the brake can be pretty compact. With a linear motor system, you don't have any rotating elements to brake on, so you need to brake on a sliding element. They make brakes that clamp on the linear rails, but they are fairly limited. What I think the linear motor guys ended up with when I left the company was a brake that was designed for wind turbines. The mounted the brake to the Y-sled (Y was vertical for us) and ran a flate blade of steel all along the y-axis for the brake to clamp onto.

You'd be surprised at how high performance a rack and pinion system can be. We usually used rack and pinion for the long x-axis. With two servo motors working together, you can get very high speeds and accuracy. We'd run Renishaw scales the full length for secondary feedback and the controls guys would comp each rack segment as well as the joints between rack segments. At low speeds, the two servos fight each other to eliminate backlash. At higher speeds, they'll work together so you can use smaller servo motors. There is a constant torque offset between the master and slave servos.
 








 
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