Podcast – How Can You Ensure Accurate Draft Angles in Mold Design?

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How Can You Ensure Accurate Draft Angles in Mold Design?
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All right, let's jump right in. Today we're talking about mold design. More specifically, draft angles.
Right.
You know, I gotta say, I'm already fascinated. Okay. Cause I just. I never thought about it. Right. You got your phone case.
Yeah.
Your coffee mug.
Oh, yeah, yeah. Even.
You know those Legos you always step on in the middle of the night?
Right. All molded.
They all started as, like, raw material. They do that was shaped in a mold.
And getting them out of that mold.
That's the thing.
Is the real trick. That's where the draft angle comes in.
So these draft angles are, like.
They're slight.
They're so slight.
Yeah. You barely notice them.
You don't even notice them.
But they're critical. They're what allows the part to release.
Oh.
From the mold.
So without the right angle.
Without it. Yeah. You get stuck. Parts.
Oh.
Warping, damage.
That sounds expensive.
It's a nightmare.
A manufacturing nightmare.
It is.
Okay, so for this deep dive, our sources are talking about software simulations and the mold's actual structure, how those all play a role in these draft angles.
It's a whole process.
It's a whole thing. So let's start with software.
Okay, so that starts with 3D modeling.
3D modeling software.
Like SolidWorks.
I've heard of SolidWorks.
Yeah. You see those cool product renders online?
Oh, yeah, yeah, yeah.
That's all from SolidWorks.
Okay.
But it's not just for making those.
Right.
It's where engineers figure out the draft.
Angles before they even make the mold.
Before they make the mold.
Oh, wow.
That's critical.
So it's like a virtual blueprint.
It is. Yeah.
Okay.
Like imagine designing a water bottle.
All those curves.
All those curves. Exactly.
Yeah.
SolidWorks figures out the exact draft angle.
For each little section.
For every section to that, it pops out of the mold.
Pops out smoothly.
Smoothly. Yeah.
That's wild.
It's pretty neat.
Okay, so you have this perfect digital model. Right.
But then there's the real world.
The real world, yeah.
Right.
Things get messy.
Things get a lot messier.
Yeah.
So how do you account for that?
Simulations.
Simulations.
That's where mold flow comes in.
Mold flow.
Okay.
It's simulation software.
Got it.
It takes that 3D model, and it simulates the whole molding process virtually. Virtually, yeah.
So you can see the material.
You see it flow into the mold. You watch it cool and then get ejected.
So this is all happening on a computer.
All on a computer screen.
That's got to be so valuable for, like.
Oh, it's incredible.
Manufacturers.
You can catch problems before they even happen.
Oh, okay.
Like if a part might get stuck.
Oh, right.
Or need too much force to get it out. Or if it might warp because of cooling. Yeah, exactly.
Okay. But what about the mold itself?
Oh, the mold itself.
Yeah. I'm picturing just like a block of metal.
Right. But it's more than that.
There's gotta be more to it. It's gotta be.
Yeah.
So the internal structure is critical.
Oh.
For these draft angles.
Okay.
And one crucial element is the parting surface.
The parting surface, that's where the mold splits open. So, like, where it comes apart.
Yeah, exactly.
To release the part. Okay. So it's like a clamshell almost kind of.
Yeah.
Two halves coming together.
Right.
And the way they come together, it affects everything. Affects the draft angle dictates it. That's so interesting.
It's like a puzzle.
A puzzle. Okay.
And instead of a static image.
Right.
We're dealing with molten materials.
Oh.
Cooling rates. It's very dynamic.
Wow.
Yeah.
Okay, so we've got the Digital design. With SolidWorks.
With SolidWorks.
The virtual simulations.
Yeah.
With mold flow.
Mold flow.
And this whole idea of the parting surface. But then you have to actually manufacture the thing.
Right. The real deal.
The real deal.
Yeah.
So I'm guessing that process.
Oh, it's high tech.
It's got to be high tech.
Very high tech.
To get that level of precision.
Yeah. They use these incredible tools like CNC machining centers. They can carve out the mold with incredible accuracy.
Like, how accurate are we talking?
Down to fractions of a millimeter.
Fractions of a millimeter?
That's thinner than a human hair.
That is insane.
It's pretty wild.
But why is that level of accuracy?
Every tiny detail matters.
Every tiny detail matters.
If the mold isn't perfectly smooth.
Okay.
It can create imperfections in the final product. In the final product.
So, like a flaw in the mold.
Yeah. Like a little scratch could become.
Could become a blemish on, like, my phone case.
On your phone case. Exactly.
Wow.
Or worse, it could affect how it works. Oh, like a phone case that doesn't fit. Right. Because the angle's off.
Oh, that makes sense.
Or a medical device that doesn't function properly.
Right, right.
Yeah.
Because of a tiny little error. Because of a microscopic error. That is a big deal.
It's a big deal.
These tiny details, they have a ripple effect on everything.
Wow. Okay.
Yeah.
So we've got the planning in the manufacturing, but even then, things can still go wrong.
Things can always go wrong.
I mean, we're talking just like the Real world.
The real world, it's unpredictable.
Exactly. Yeah. So you've got to monitor things.
You got to keep an eye on things constantly. Constantly, yeah.
Okay, so how do you do that?
Well, there's some cool tech for that.
Oh, there's always cool tech.
There is.
Yeah.
They use things like cmms, C. Yeah. Coordinate measuring machines. Okay.
What do they do?
They use lasers and sensors to inspect the molds and they can catch any deviations.
So like a tiny robot inspector.
It's like that. Yeah.
Looking for flaws.
Exactly.
Wow. That's.
It's pretty impressive.
It's really impressive.
Yeah.
Okay. But even with all that, there's still research and development always happening in this field. Always pushing the boundaries because technology is always.
Technology never stops.
It never stops. Yeah.
Nope.
So what are they researching?
New materials.
Okay.
New manufacturing processes, new simulation software.
So it's not just about making things.
It'S about making them better, faster, cheaper, cheaper, more efficient, but it's also about.
And more sustainable sustainability.
That's a big one.
Yeah. Because there's this pressure now, a lot of pressure to be more eco friendly.
Yeah. To reduce waste.
Reduce waste.
Conserve resources and the whole carbon footprint, the whole thing.
Right.
Yeah.
So how are mold designers responding to that?
Well, they're looking at eco friendly materials.
Like what?
Like bioplastics.
Oh, yeah.
Which come from renewable resources or recycled plastic.
Okay.
They're also optimizing the mold designs to use less material. To use less material. Yeah.
Yeah. And create less waste.
Exactly. So it's a holistic approach.
Yeah.
Thinking about the whole life cycle.
Wow.
Yeah.
So these tiny little details, they're connected to big things. Yeah. To sustainability.
To sustainability. Yeah.
Like resource management, the whole picture. This is incredible.
It is, isn't it?
I'm learning so much.
Me too.
Honestly, this is fascinating.
It is fascinating.
It's like I'm looking at everyday objects.
In a whole new light.
In a whole new light that I never thought about.
Easy to take them for granted.
It is all the thought, work and effort and precision that goes into them.
It's mind blowing.
It really is.
Okay.
Okay. So last time.
Yeah. We were talking about.
We were talking about how these molds are made.
All those steps.
All the steps.
Right. I mean, it's a complex process. It's so complex things are bound to go wrong.
Right?
Yeah.
So what happens?
So when those draft angles go wrong. Yeah. When they go wrong, you gotta fix them.
You have to fix them.
You can't just start scrap the whole mold.
No, no, no.
Okay. So how do you fix It.
It depends.
It depends on the problem, on the material, the mold.
Okay, so there's no, like, one size fits all?
No magic bullet solution? Nope.
Okay, so walk me through it.
All right, so one way is edm. Edm? Electrical discharge machining.
Okay. I'm already lost.
It's pretty sure.
Okay.
Basically, they use electrical discharges.
Like little lightning bolts. Yeah.
Like tiny, little controlled lightning bolts to remove material, to reshape the mold.
So it's super precise.
Super precise.
Okay.
Especially for hard materials like hardened steel.
Where you couldn't just.
You couldn't just grind it away.
Right.
EDM is a way to go.
Okay, so EDM for, like, the small stuff.
Yeah, for the details.
The tiny details.
Right.
What about if there's, like, a big mistake?
A big mistake. You might have to grind it.
Grind it?
Yeah. Use abrasive wheels.
Oh, okay.
To remove material.
So that's more like.
It's a bit more old school.
Yeah.
But it still takes a lot of skill.
You can't just hand it to anybody.
No, no, no.
Okay.
You need someone who knows what they're doing.
Right. Who understands the material, the whole process.
This is blowing my mind.
I know, right?
It's a whole world. It's a whole hidden behind the scenes.
Yeah. And it's all about.
It's about precision. Precision and craftsmanship.
Yeah.
It's pretty incredible.
It's making me look at my phone case differently.
I know, right?
Like, I just thought it popped out of a machine.
Well, there's so much more to it.
There's so much more to it.
Yeah.
Okay, so we've talked about fixing those angles.
Right.
But the material itself, the material matters. Matters too.
It does, big time.
Because like you were saying before.
Yeah. With mold flow, some materials are easier.
They're more forgiving.
More forgiving. Yeah.
When it comes to those angles, you.
Can get away with a little bit more.
Okay, so what kind of materials are we talking about?
Like some plastics. Plastics, they're a bit more flexible, but.
Then metals are more.
Metals are tricky.
They're not as forgiving.
No. If the angle's off.
Yeah.
It can stick. Stick in the mold, warp, even damage the mold.
Oh, wow.
Yeah. It's a delicate balance.
So it's not just about.
It's not just geometry.
Shape.
You got to think about the material.
The material's properties, how it behaves.
How it behaves under pressure, under heat.
It's like a dance.
It is a delicate dance between the.
Mold, the material, and the process. The whole process.
It's all connected.
Okay. So that's like the current state of.
Things, the here and now.
Yeah.
But what about the future?
What about the future of mold design?
That's where it gets really exciting.
Okay, I'm intrigued.
So our sources talk about research and development.
Right.
They're always innovating, always pushing the boundaries.
Yeah. So what's next?
Well, One thing is 3D printing.
3D printing for molds.
For molds, yeah.
How does that work?
It's amazing.
Okay.
You can create these incredibly complex molds.
That you couldn't make before that you.
Couldn'T make with traditional methods.
It's like opening up a whole new world. A whole new world of possibilities.
Exactly. And one really cool application.
Yeah.
Is conformal cooling channels.
Conformal cooling channels. Okay.
Remember those?
Yeah. The ones that, like, they follow the.
Shape of the mold.
They're not just straight lines.
Exactly.
Okay.
With 3D printing.
Yeah.
You can make those channels.
Oh, wow.
Like never before.
So you get.
You get better cooling.
Okay.
Faster cooling.
Which means.
Which means faster production.
Oh, I see.
Less warping, less waste, less energy.
It's like a win. Win.
It's a huge win.
Wow. So 3D printing, it's a game changer. It's a game changer.
Yeah. For mold design.
This is amazing.
It is pretty cool.
It's so much more than just.
It's more than just plastic parts.
Yeah.
It's the future. Welcome back for the final part.
Yeah.
The final part of our mold design. Deep dive.
It's amazing to me. We started with draft angles, and look where we are now.
So much to uncover.
I know, but even with all these advancements, there's got to be challenges.
Of course. Always challenges.
So what are mold designers facing today?
Well, one of the biggest is complexity. Complexity of product designs.
What do you mean?
I mean, consumers want sleeker products.
Oh, right.
More functional, better looking.
So, like, the things we buy are just getting more and more complicated, and that means the molds.
The molds got to keep up.
So they're getting more complex too.
Way more complex.
Okay.
And that's a problem is a challenge.
Okay.
Because you gotta balance design with manufacturability.
So, like, how it looks versus how.
You actually make it.
Right. Because you could design something amazing, but.
If you can't make the mold, it's useless. It's just a pretty picture.
Yeah.
So mold designers.
Yeah. They're walking this tightrope between art and engineering.
You got it.
Okay. What else?
Well, another big one. Sustainability.
Sustainability, Right.
Everyone's talking about it because we have.
To be more eco friendly.
More eco friendly.
Reduce our impact.
Okay, so how does that apply to mold design?
Well, first off, the materials.
Okay, so like using different plastics.
Different plastics? Yeah.
That are more sustainable.
Like a bioplastics.
Right. Made from plants.
Yeah.
Renewable resource or recycled plastics.
Give those materials a second life, reduce, reuse, recycle. Right, exactly.
So it's not just about swapping materials.
No. You also got to optimize the mold.
Itself to use less material.
Use less.
Yeah, create less waste.
Less waste.
So like more efficient designs.
Precisely.
Wow.
So sustainability, it's a huge factor in mold design.
And it's only going to get bigger.
Absolutely.
Okay, so we've got complex designs.
Right.
We've got sustainability. But there's one more thing, Right.
One more big one.
Speed.
Yeah.
Because in today's world, everything's got to be faster, faster, faster, faster.
Time is money.
Right. So how do you speed up mold design?
Well, simulations help.
Oh, right. Like mold flow.
Like mold flow, yeah.
Okay.
By simulating everything virtually, you can catch problems early and you can optimize the.
Design process because you don't waste time.
No, wasted time.
Making prototypes.
Exactly.
And then there's automation.
Oh, yeah. Automation's huge.
It's like robots building molds.
Robots building molds.
That is so cool.
It's pretty wild.
So the future of mold design, it's a blend. A blend of what?
Of human expertise.
Okay.
And cutting edge technology.
So like AI, robots, the whole nine yards. This is incredible.
It's a really exciting field and, you know, it's crazy. I started this deep dive.
Yeah.
Thinking it was going to be about.
Just some simple angles.
Yeah, just some angles.
But it's so much more. It's about precision, it's about innovation. It's about pushing boundaries and shaping the future.
Literally shaping the future.
That's what mold design is all about.
I'm blown away.
Me too.
To be honest, this has been such a journey.
A real deep dive.
It has.
Yeah.
And it's made me realize.
What?
That there's so much more to the world.
Oh, absolutely.
Than we even realize.
There's always something new to discover.
So keep exploring, learning. Keep asking questions.
And you never know what you'll find.
Thanks for joining us.
It's been a pleasure. And until next time, keep on