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On ‎12‎/‎11‎/‎2017 at 3:51 PM, shion said:

 

What a joke.:rofl:

I will take your Kfir kit if you do not want it. Since it is so bad I will even give you half price for it so that you are not at a total lose. Or I have a Kinetic kit I will trade you for it. Just let me know... Always great to help out a fellow modeler.

 

 

Brandon

 

Edited by Bravosierra001
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6 hours ago, Bravosierra001 said:

I will take your Kfir kit if you do not want it. Since it is so bad I will even give you half price for it so that you are not at a total lose. Or I have a Kinetic kit I will trade you for it. Just let me know... Always great to help out a fellow modeler.

 

 

Brandon

 

 

 

Sorry but it is a joke.

 

Warpage comes with delay, so tests made above the injection press are simply useless.

And it's unrealistic that people could take picture of each part of a batch.

And the atonishing part: it didn't work.

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..." And it's unrealistic that people could take picture of each part of a batch. "...

 

I am sure it#s not done like that! Camera control is a standard procedure in the CAM process. The camera sends the picture to a software that has a pattern pre-defined and compares the picture with the pattern. This can be VERY accurat and quick. The police and soon your cell phone use the same process to recognize faces and compare them with a data base...! Of course this process will fail, as you rightly said, if the part changes shape as it cools down...so the Camera checking has to be done later then now.

Edited by anj4de
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1 hour ago, shion said:

 

 

Sorry but it is a joke.

 

Warpage comes with delay, so tests made above the injection press are simply useless.

And it's unrealistic that people could take picture of each part of a batch.

And the atonishing part: it didn't work.


The usage of cameras and image recognition software is wide spread in industry. It´s not like there´s an employee with a digital SLR shooting pictures that are looked at later in the office.
The process is wholly automated and takes mere seconds. But as is usual with automated processes, they are only as good as the people implementing them. I know of an anecdote where a robot used a camera to find and pick up engine parts for grinding and grading. When it had emptied a crate of unfinished parts it tried to pick thin air in the crate. Turns out the parts left a greasy part-shaped stain on the bottom of the crate, which the robot interpreted as a part and tried to pick it up.

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You both describe a modus operandi in a high-quality, high-precision, high volume parts injection molding.

 

I'm sorry to say this, but it isn't the case here.

We have here a pretty basic plastic injection manufacturer.

It's not a story about an another business company which decides to make plastic model kits.

It's a story of a plastic injection company which decides to use their tools and strengths to make plastic model kits.

 

And what happens here?

- They forgot to finish the mold surface on the main parts of a kit.

- they made a pretty obvious design error on at least one mold.

 

You don't put fancy part checking devices for a 5000 parts batch.

You put a human.

 

Let's see how Tamiya handles this:

 

tamiya_philippines_cebu_05.JPG

 

in video: 

 

 

 

So it's not rocket science, the best way to have a plastic injection part without problem is... to design it the best way first.

Edited by shion
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Got it. To never have any sort of production issues ever one should simply just make everything perfect in every imaginable way from the start.

 

If only someone has ever thought of that radical idea before.:rolleyes:

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On 12/11/2017 at 4:43 PM, shion said:

 

 

Hello.

sadly,  it is not an extraction problem.

If it was an extraction problem, it would be fixable.

But it is not.

 

It is a design problem.

Simply put: the mk-82 one-piece part is too thick to be molded.

 

The part material is normally PS.

PS admits a wall thickness between 0.889 mm and 3.81 mm.

 

Let's caculate the wall thickness of a mk82 in 1/48.

Diameter of the real bomb body: 10.75 inch so 273.05 mm.

In 1/48, a thermoplastic one-part mk 82 will have a wall thickness of 5.688 mm.

5.688mm is way beyond the chart to make a one-part design in these polymer.

 

So what happens here?

Because the part is too thick,

it takes ages to fill,

it takes pressure to stay at the nominal sizes

and worst, it takes ages to cool.

And because when the part is extracted, the core of the part is not cold, the part continues to shrink internally and the cold surface can't follow this intern shinkrage and this is the result: warpage.

An annex problem here is the fact that the cooling isn't done when the part is extracted, so the part could look OK at first glance, but hours later,  warpage appears.

 

 

 

 

 

 

How did it work on other missiles then? Like R-33 ??

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22 hours ago, Bravosierra001 said:

I will take your Kfir kit if you do not want it. Since it is so bad I will even give you half price for it so that you are not at a total lose. Or I have a Kinetic kit I will trade you for it. Just let me know... Always great to help out a fellow modeler.

 

 

Brandon

 

 

 

Darn it, beat me to the punch!:rolleyes: Never was a fan of the Kfir until today so put me on the list for any kits not wanted lol!

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Hi, All,

 

Looks like guys are very interesting with plastic injection. As a technical guy, I join you with some opinions here.

 

Yes! AMK injection is not that hi-tech. It is simply plastic injection, same like all other manufacturers. We also check plastics visually by eyes, have notice on machnes in red big letters like "Beware of Short shot", etc. All are the same.

 

Unfortunately, Mk 82 bomb is not that easy to check visually by eyes, especially when you see from top. Ryan noticed it just when he was taking pictures. So, what can do is, during injection, take pictures regularly of the bomb, and zoom in the computer to see if there is deformation or not. It is just simply one more procedure of checking.

 

About the DESIGN, surely, we knew it is with higher risk of shrinkage and cooling problems. But to the theorectical data below may not be that true.

 

****** The part material is normally PS.

****** PS admits a wall thickness between 0.889 mm and 3.81 mm.

 

Yes! We also use PS same like all other manufacturers. What we had done without any problem, are wall thickness between 0.20mm to 6.50mm. If you are intested, you can check out our R-40 for MIG-31 if you have one. The body is with diameter 6.50mm while the fins with minimum thickness of 0.20mm.

 

So, the design of Mk 82 should not be a problem. Let's our new batch of production then.

 

 

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23 hours ago, Berkut said:

Got it. To never have any sort of production issues ever one should simply just make everything perfect in every imaginable way from the start.

 

If only someone has ever thought of that radical idea before.:rolleyes:

 

Haha. Anton,

 

Radical idea? It is just simply make it "easy to build" for modelers.

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On ‎2017‎年‎12‎月‎14‎日 at 1:38 AM, shion said:

You both describe a modus operandi in a high-quality, high-precision, high volume parts injection molding.

 

I'm sorry to say this, but it isn't the case here.

We have here a pretty basic plastic injection manufacturer.

It's not a story about an another business company which decides to make plastic model kits.

It's a story of a plastic injection company which decides to use their tools and strengths to make plastic model kits.

 

And what happens here?

- They forgot to finish the mold surface on the main parts of a kit.

- they made a pretty obvious design error on at least one mold.

 

You don't put fancy part checking devices for a 5000 parts batch.

You put a human.

 

Let's see how Tamiya handles this:

 

tamiya_philippines_cebu_05.JPG

 

in video: 

 

 

 

So it's not rocket science, the best way to have a plastic injection part without problem is... to design it the best way first.

 

Thank you for sharing this! Shion,

 

It is quite interesting to me.

 

I am not offending any one here, but some of my personal feeling only here.

 

This company is who, I (or we) had been learning design and mould making from their plastics in the past over 10 years, by a big contribution to their sale. Be honest, their design and mould quality is still the best!

 

From those,  big red letter "beware of short shot", paints of injection machine off and getting rusted, moulds got rusted, mess of everything on mould making work bench, etc., I feel better with the difficulty of production management now, as every one has this problem. I should not complain any more.

 

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Comparing Tamiya who have basically unlimited resources ie there own injection plant to a company begging for time to get its plastic injected ie F-14, Kfir is pretty unrealistic.

If every company had Tamiyas resources then you can fire at will but Tamiya releases one new aircraft every 1-2 years in each scale if we are lucky.

Expecting Tamiya quality from any other manufacturer i believe is wishful thinking and it isnt going to happen. Get close yes..aim for the quality yes but with a modelking division funded by RC cars, toys etc the ability to test unlimited test runs etc to achieve ideal fit and design how can anyone compete?

I really hope AMK get the production issues sorted and improve the quality for the sake of the F-14.

 

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14 hours ago, Sio said:

 

About the DESIGN, surely, we knew it is with higher risk of shrinkage and cooling problems. But to the theorectical data below may not be that true.

 

****** The part material is normally PS.

****** PS admits a wall thickness between 0.889 mm and 3.81 mm.

 

Yes! We also use PS same like all other manufacturers. What we had done without any problem, are wall thickness between 0.20mm to 6.50mm. If you are intested, you can check out our R-40 for MIG-31 if you have one. The body is with diameter 6.50mm while the fins with minimum thickness of 0.20mm.

 

So, the design of Mk 82 should not be a problem. Let's our new batch of production then.

 

 

 

There's a rib accros the longitudinal plane of the part.

In the cooling process, it acts as a restrainer of warpage.

 

There's the same phenomenon with the Griffin bomb.

 

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7 hours ago, dehowie said:

Comparing Tamiya who have basically unlimited resources ie there own injection plant to a company begging for time to get its plastic injected ie F-14, Kfir is pretty unrealistic.

If every company had Tamiyas resources then you can fire at will but Tamiya releases one new aircraft every 1-2 years in each scale if we are lucky.

Expecting Tamiya quality from any other manufacturer i believe is wishful thinking and it isnt going to happen. Get close yes..aim for the quality yes but with a modelking division funded by RC cars, toys etc the ability to test unlimited test runs etc to achieve ideal fit and design how can anyone compete?

I really hope AMK get the production issues sorted and improve the quality for the sake of the F-14.

 

 

I really don't see the point, here.

 

The discussion deals about expensive systems to check quality of parts above the injection press.

I show that Tamiya itself doesn't use this.

And it will be difficult to say that Tamiya doesn't have the money and the production numbers to make this type of investments.

So, if they don't use these, it may be because it simply don't worth the cost.

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35 minutes ago, shion said:

 

There's a rib accros the longitudinal plane of the part.

In the cooling process, it acts as a restrainer of warpage.

 

There's the same phenomenon with the Griffin bomb.

 

Yes! Right!

 

The rib helps preventing deformation during cooling.

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27 minutes ago, shion said:

 

I really don't see the point, here.

 

The discussion deals about expensive systems to check quality of parts above the injection press.

I show that Tamiya itself doesn't use this.

And it will be difficult to say that Tamiya doesn't have the money and the production numbers to make this type of investments.

So, if they don't use these, it may be because it simply don't worth the cost.

I think both of you are right!

 

Just for injection quality checking, it is not worthy to use hi-tech equipment.

 

But for a whole kit checking, that may need too much work and time, and these back and forward activities cost too much. Design, mould making, trial, then, design cahnge, mould change, trial again, and this could be again and again. That realy costs a lot.

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2 hours ago, shion said:

 

I really don't see the point, here.

 

The discussion deals about expensive systems to check quality of parts above the injection press.

I show that Tamiya itself doesn't use this.

And it will be difficult to say that Tamiya doesn't have the money and the production numbers to make this type of investments.

So, if they don't use these, it may be because it simply don't worth the cost.

Well, in view of "shrinking", we have really a lot of "experience" :)  A lot of factors affecting it, but checking the parts by human is not possible (QC), instead running a Process Control (mold design, injection machine upgrade) is more reliable. From the latest experience, a new servo-motor type injection machine can really help to reduce the production error (of course, if the tooling was not right at the first time, it still cannot help). 

 

Just my 2 cents.

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14 hours ago, shion said:

 

I really don't see the point, here.

 

The discussion deals about expensive systems to check quality of parts above the injection press.

I show that Tamiya itself doesn't use this.

And it will be difficult to say that Tamiya doesn't have the money and the production numbers to make this type of investments.

So, if they don't use these, it may be because it simply don't worth the cost.

 

You miss the point entirely.

By the time a Tamiya parts checker is looking at parts there is ZERO possibility of a design defect having made its way through the design process as AMK have had happen.

When a Tamiya kit reaches production they are only looking for short shots or other imperfections in production not the design/shape/look of the parts themselves.

To ensure quality and fit you would imagine numerous test runs and builds to confirm the standards we have come to expect prior to comitting to production.

Tamiya doesnt “need” these expensive QC cameras etc because by the time they commit to production all the wrinkles are well and truly gone.

Its simply then parts QC not design QC as the design side has been tested to ensure  the highest quality fit etc.

To be able to do that you need full time access to molding machines etc to run the test shots etc to get it to that point.

AMK clearly dont have that access and need to rely on other technology clearly not as reliable due to limited access to machinery.

When the tech doesnt work the system breaks down Kfir parts case in point.

People comparing AMK to Tamiya from a quality control/production view is simply not realistic.

 

 

 

 

 

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...back to my issue...where and when will the new Kfir be available in Europe or even Germany? I do not give a sh... about the bomps personally since mine will be a clean aggressor plane. Just would like to bable to buy it.

 

thanks

Uwe

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9 hours ago, dehowie said:

 

You miss the point entirely.

By the time a Tamiya parts checker is looking at parts there is ZERO possibility of a design defect having made its way through the design process as AMK have had happen.

When a Tamiya kit reaches production they are only looking for short shots or other imperfections in production not the design/shape/look of the parts themselves.

To ensure quality and fit you would imagine numerous test runs and builds to confirm the standards we have come to expect prior to comitting to production.

Tamiya doesnt “need” these expensive QC cameras etc because by the time they commit to production all the wrinkles are well and truly gone.

Its simply then parts QC not design QC as the design side has been tested to ensure  the highest quality fit etc.

To be able to do that you need full time access to molding machines etc to run the test shots etc to get it to that point.

AMK clearly dont have that access and need to rely on other technology clearly not as reliable due to limited access to machinery.

When the tech doesnt work the system breaks down Kfir parts case in point.

People comparing AMK to Tamiya from a quality control/production view is simply not realistic.

 

 

what are you talking about?

Of course, AMK have access to molding machines to run test shots, they're a injection molding company and they inject parts for clients.

Have you really miss the discussion about the pre-order, when they say that they don't have the window in their schedulde to inject the F-14 parts?

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Man y’all are some serious folks trying to have a serious debate about parts, quality control, injection processes, etc. Would it not be best if that talk was moved somewhere else so those of us that want to just discuss the Kfir model may do so? Or how about not drag it on any further? 

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15 hours ago, shion said:

 

 

what are you talking about?

Of course, AMK have access to molding machines to run test shots, they're a injection molding company and they inject parts for clients.

Have you really miss the discussion about the pre-order, when they say that they don't have the window in their schedulde to inject the F-14 parts?

 

You must be missing something completely obvious in my point as what you just stated is EXACTLY my point.

AMK struggle to get access to mold facilities due to the busy production of the parent company.

This means they dont have the access a company like Tamiya does as they have access whenever they want. Hence Tamiya can tweak there molds as much as needed to eliminate any issue other than short shotting.

AMK rely on advanced post molding checking Tamiya relies on making the kit perfect before molding. So when AMK’s tech breaks then so does the QC they rely on and you end up with the Kfir situation with inferior parts getting into boxes.

Im not sure what your on about as i have made it very clear that people expecting Tamiya quality(guys above) have expectations that are pretty high and how AMK has done so well so far without an issue has been great.

If you cant see that a company with limited access to mold machinery like AMK will have issues compared to a company with unlimited assess ie Tamiya then no amount of Philipino’s on 5 cents per hour will help.

 

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