A question in relation to the decision to chop legs in half on sprues.

[Rodiger]

I was building some Rubric Marines today and I was wondering why on the sprue quite often 1 leg, or half a leg is a separate bit, this isn’t anything specific to Rubric Marines, I’ve seen it on lots of kits, it was just this one that got me wondering. Does anyone know why the sprue is built like that? It just seems strange as many pairs of legs on kits are complete. There are actually many things that puzzle me with the decisions taken with how they break up the models, some are obvious, so you can change the pose, but this is a single pose. The only thing I can think of is that maybe the completed legs would be too wide for the mould, but I’m sure there are wider parts on kits.    

[ManlyMuppet88]

It’s about sprue composition, not model posing. Not always logical to us but they have to cut things up in weird places sometimes to cram as much as possible onto the sprue. 

[AGPO]

As @ManlyMuppet88 says, spruce composition is one factor, achieving dynamic poses whilst minimising mould lines are others. That last point is huge when comparing the newer models to the older ones. I put together some seraphon recently and the mould lines were horrific.

[Rodiger]

That's a good point about the space consideration, seems weird that making a pair of legs in 2 parts would free up space but it must if they keep doing it. I have been very impressed recently with  how much they get on a sprue, I bought some big models thinking there will be loads of sprues in the box but there is only like 2 or 3. You can totally tell the age of a kit just by looking at the amount of space on sprues, as with the lack of mould lines. I don't know if you saw the Kal Jericho and Scabs sprue but my first thought when I saw that was it looked like a 20 year old one because of how much space was there. 

I wish GW would do some behind the scenes of their factory and the actual technical side of making the models, could be concerned about trade secrets though. 

Edit.

I've just had a look at that Kal Jericho and Scabs sprue and they both have a leg cut off, but there is loads of space all over that sprue. Quite strange. 

Edited July 1, 2019 by Rodiger

[kenshin620]

Yea it's mostly about how to utilize the sprue/runner space.

 

Though some other companies took it too far, like what happened with the ill fated Robotech (cough macross) game. I can't believe each arm requires +5 parts...

[Bubbatron]

Some Malifaux minus are like that, seems like the person doing the sprue layout got a bit too chop happy - feet seperate from legs, front and back heads, seperate faces 😱

[divineauthority]

It can also be due to the way plastic injection molds work and the fact you can't get undercuts in that process. Breaking up pieces can allow a more detailed kit as it removes a lot of the limitations.

[spaint2k]

The answer is what divineauthority said: you get more detailed legs like this. An easy example to see this on is the 40k Chaos Terminators and the Chaos Terminator Lord. IIRC his legs are separate and they have better detailing behind the knees, while the regular guys have flat areas due to the lack of undercuts.