Defiance Games USMC Marines!

[anevilgiraffe]

they might almost be able to sell something soon... oh wait...

Actual sprue pics!!!! - but not final sprue pics?

The first test shots went off yesterday afternoon and the toolmaker was very happy with the result. The whole mold filled - including the four bases at either end. We did get some flashing on several parts - which is the result of too much pressure being applied. They are now checking the problem areas and widening the gates to those parts so that the plastic can flow more smoothly with less pressure. It is better to start off with smaller gates and widen them than to have large once that need to be welded smaller. (Please note this is shot with basic high impact polystyrene - it's not colorized and is translucent - NOT the final plastic) More updates once they do the next shots.

[Dr.Falkenhayn]

so where`s the "very special dynamic Legs then?is that a blurry Pic or is that Flashing on every Part 

[DoctorPete]

Looks like flash on every part to me.  Looks like they will give birth to bugs before giving birth to Marines.  Why does this phrase keep running through my head: "They mostly come out with flash.  Mostly."

[zizi666]

I refrained from joining the rant so far, but now that I've seen the pic of the test shot and the incredibly stupid explantation that accompagnies it, I've got to say : what a bunch of retards.

molten plastic is a fluid. by narrowing a channel you create a pressure drop, so, if they are going to widen the gates to those parts that get too much pressure they will submit them to even more pressure...
Now theorethicaly, a mold is so rigid, it can't deform. if you put too much pressure on the plastic, you push your mould open, entirely.
If you look at the sprue in the top left corner, you see it isn't filled completely in one corner. one way to overcome this is to put more pressure on the material which in this case would lead to even more flash and you can clearly see that's what they've done with the other sprues.
Another option is to raise the core temperature of the material and/or the mould, giving it better flow capacity so you need less pressure.
Then there's the manner of injecting. You can clearly see that most flash is concentrated around the center (or mainsprue.) If they were to use less pressure at the start of their injection and build up pressure towards the end, it might just be that first material starts to cool round the edges, while still filling the last parts. cool material = no fluid hence no overflow/flash.

So my best bet : this mould is far from ready for production (and if they do widen those gates he's talking about, it's probably ready for the scrap pile)
another possibilty is the injection engineer. Could be they use some amateur that knows how to get plastic in a mould but doesn't know how to do it properly...

[carlos marighela]

Meanwhile those perfidious KA owners of their old business actually seem to have new product out and for what it's worth it actually seems to be an improvement on the old WF.

http://wargamesfactory.com/webstore/world-war-2/wwii-german-infantry-platoon

That really must rub salt into the wound.

[anevilgiraffe]

I think you need a wound first...

[Ironworker]

It's a step up from the constant vapor minis but it still doesn't look ready for prime time. 

[n815e]

Zizi666 : when you expand the channels you lower the pressure.  Narrow them and you increase the pressure.
You got it reversed.

[CptJake]

It should not be too long before they have product now. Maybe.....

Yep, probably right on March 23rd   

[zizi666]

Zizi666 : when you expand the channels you lower the pressure.  Narrow them and you increase the pressure.
You got it reversed.

No, after a narrowing you create a pressure drop. By enlarging the gate the material has less resistance flowing through it and thus maintains the pressure used to inject the material.
Maybe we're looking at it from different sides. I'm referring to the pressure in the actual cavities behind the gates. If you're referring to the pressure buildup in the sprue before the gates, then you're right in saying pressure will drop by enlarging them, but as far as injection molding goes, that's just plain wrong.
fluids always try to take the easiest way, in this case through the gate. The actual creation of flash is because at some point the material can't flow any further and then the pressure builds up high enough to push both mould halves away from each other. This occurs in the cavities, not in the runners.
Again : they need to get the material to the outer parts before that happens ergo they need to widen the cannels to those parts or narrow the gates to the parts closest to the injection point so they don't fill so fast.
OR they need to get a decent injection moulding technician.
It is possible to open up a perfect mould by using way too much injection pressure from the start and too little mould closing pressure, but if that were the case, we'd be talking about a genuine moron.

[tnjrp]

Well, at least they got their test shots off... That doesn't still make the Marines "in stock" but possibly it's a step in that direction.

[Sangennaru]

Zizi666 : when you expand the channels you lower the pressure.  Narrow them and you increase the pressure.
You got it reversed.

a whider channel make the plastic flow, so the local pressure temporary decrease.
I don't know how exactely the plastic injection goes, but even though they look quite dumb, i think that they know how to make a mould.

Meanwhile those perfidious KA owners of their old business actually seem to have new product out and for what it's worth it actually seems to be an improvement on the old WF.

http://wargamesfactory.com/webstore/world-war-2/wwii-german-infantry-platoon

That really must rub salt into the wound.

indeed!

and i have to say. I ALSO LOVE THEM! It is the first WF piece that i like, but it's very great!!

[Dewbakuk]

how on earth do you guys know this stuff?

It's flow mechanics, essentially liquids (most of them) react a certain way to certain conditions.

Zizzi666 and n815e are both correct but they're talking about different effects
Essentially if you narrow a channel there is a build up in pressure where the liquid enters the channel and the liquid will pass through the channel at a higher pressure, however where it exits the channel the liquid will be entering a void and the pressure will drop. By widening a channel the flow is maintained and the pressure stays more constant.

[Sangennaru]

yep, what dewbakuk said. It is not a high pressure tank, the amount of plastic is fixed. but the path it follows could vary by the different channel settings!

how on earth do you guys know this stuff?

Physics... only  (almost) bachelor degree, for now. still young.

[aecurtis]

Penny?  Penny?  Penny?