"The curious nature of mold lines on plastic minis." Topic

So I made this thread kind of because my brain has a strange, peculiar sort of approach to mold lines.

Being away from the hobby for a long time and getting back into it in 2015, I've done a lot of hobbying in the past three years, mostly in plastic and resin.

Cleaning mold lines is generally a part of cleaning up plastic parts before assembly.

But in doing rank and file armies in plastic, in this case fantasy, for some reason visually they didn't distract me enough to worry about. Same went for plastic terrain kits like GW's. Mold lines didn't bother me nor did seams between parts.

I did an entire 100+ mini. army of GW dwarves and while I was obviously careful in cleaning sprue flash, mold lines often times were in places on the mini. or were shallow enough that I didn't feel a need to totally remove them. Indeed when I look at my dwarf army I would say that in 95% of instances you really can't see any severe mold line distraction anywhere.

However, I think it was because the dwarf boxed sets and sprues were designed in a way where mold lines weren't in overly obvious places and were disguised when painted.

That being said, I do fill gaps in plastic minis where there's visible seams. I particularly do this on large character models. But again, for like rank and file I don't generally fill seams.

For military models or sci-fi models for dioramas, I would always clean mold lines. To me that was never a question. I guess I'm just not sure why having some lines and seams wouldn't bother me on rank and file wargames figures but that it would on a diorama model.

For me personally, when an army is all visually together as one entity on a tabletop, seams and mold lines aren't as big an issue than if you were to build a large, individual model like a Tiger Tank or say an X-Wing fighter, or a really large fantasy model like The Great Unclean One, or whatever.

But this past week I was doing 40k stuff for Kill Team. It was one of the first times I was doing like an all-one color military-type uniform on a squad of Cadians. The mold lines HAD to be thoroughly taken off because drybrushing over them left a REALLY obvious, visible line. I think maybe because in this case I was doing a wash over a base coat followed by a drybrush. So of course the wash would collect around a mold line and then drybrushing would drybrush around it. Drybrushing would bring out the mold line the same as it would any detail on a model.

In previous fantasy assemblies and painting, I was doing more layering of paint in which case mold lines aren't as apparent as when you are drybrushing over them.

Any way, just wanted to know how you approach mold lines and seams and if you clean them in ALL cases or just some. The Cadians kind of "woke me up" to how visible mold lines can be on a brightly, single colored uniform. So I've kind of just shifted to the philosophy of cleaning all mold lines no matter what the mini. is.

Curious as to your thoughts on this.

…one additional thought to this is an observation. Over the past three years or so companies like GW have advanced so far in how they design sprues that they're creating parts that fit together in ways where mold lines are actually covered up during the assembly. Noticed that with some of the AOS Nighthaunt and some of their Orruk stuff.

But of course any GW kits from the 2000s would have more obvious mold lines.

Baranovich,

I think you have a great outlook with regard to the hobby and the issue of mold lines. Me, I cannot stand the mold lines. I find them to be a visual distraction when assembling, priming and painting.

The existence of mold lines leads me, in some cases, to go to resin models where I can. It really comes down to opportunity cost of time. I can spend lots of time cleaning annoying mold lines or, in some cases, I can spend more money but less time time prepping the miniatures for painting.

By way of example, I can clean, prep and glue together five plastic Flames of War tanks. Or, I can spend a little more and assemble five resin (with pewter parts) Khurasan tanks. The former may cost a little less in box sets (but, with FoW that is not always the case), while the latter may cost a little more in box sets but allows me to get to painting quicker.

That said, mold lines are endemic in metal miniatures as well. Which, by the way, I find equally as annoying.

I try to remove mold lines as part of my clean up process. Mold lines on faces are incredibly annoying and all too often very hard to get at and clean up. I hadn't thought about it, but layering paint on would minimize the effect of mold lines, at least compared to dry brushing. I must try this.

Grelber

Thanks for the insights guys, much appreciated.

Indeed, it depends so much on where the mold lines are located. I hate them because it adds so much time to preparing models in addition to removing sprue flash.

Mold lines over faces or over the top of helmets that are rounded are pretty much impossible to ignore. Like the helmets on my Cadians, a mold line ran right across the tops of those and down the sides. I had to clean those, no way you could ignore it.

And as you reference, mold lines across faces are impossible to ignore.

I think more forgivable are when mold lines run down the side or undersides of arms and legs and boots. But even so those are pretty obvious if drybrushed over. Mold lines that are actually underneath arms of course are generally never seen so those at least could be left alone.

Another issue I run into with mold lines are the ones I run into with sprue flash. Even when I thoroughly remove sprue flash, I find that if I do a spray primer as a basecoat, such as like Macragge Blue for space marines you can still see the "shadow" of where the flash was removed. It's a different texture from the surrounding plastic and so even though it's covered in blue like the rest of the model you can see the shadow. I don't stress over that too much either, unless I was doing a professional diorama purely for a contest or display. Then I'd probably sand it down further to make it truly invisible.

Yeah, the layering like three shades of paint to create shading and lighting can be useful for minimizing the effects of mold lines on areas like the outside of legs and feet.

I've also had difficulty removing all of a mold line. Sometimes it feels like I've got it right down to the surface of the plastic, only to find that it STILL shows up when I put a wash and drybrush over it. So I just remove it as thoroughly as I can and at least eradicate most of it if not all of it.

What's nice though is that most companies, including GW try to avoid putting lines across faces. They generally run them over the top of a head and then down the sides of the body. That's easier to cope with than a line going across a face. Indeed that's a nightmare!

@Grelber,

Yeah, the Wargames Foundry triage system works well for that. Because all the paints are layered and used at full strength, mold lines are there but are actually covered in color. The key with the Foundry range is that you don't need to do washes! Washes are where you run into trouble with mold lines because as I said first the wash perfectly outlines the mold line. Then the drybrush finishes it off by perfectly highlighting it!

With washes and drybrushes eliminated you never actually give a chance for a highlight or accencuation to the mold line. It's just covered in color.

I liked the GW LotR plastic figures. The mold lines followed the edges of armour or helmets or similar wherever possible, minimising the work needed.

I hate mold lines. HATE. I hate seeing them and I really hate trimming them off. Worst part of the hobby for me.

We hates it, Precious! We hates it forever!

I trim off flash and the worst of mould lines from my 1:72 plastic figures with a craft knife, then run a hot miniature welding welding iron around the figure to make any such lines disappear.

Rod

I come from an IPMS model-building background and from force of habit remove any mold lines I find. I admit that I have caught myself holding part under a bright light looking for them so I might be a bit obsessive…..

I have an accepting relationship with mold lines. I been very frustrated when I've ruined a feature of a model (like a nose) when trying to remove a mold line. My tolerance of mold lines is dependent of the risk and difficulty in removing them. The rubbery Hat figures are the worst. I've started using a hot needle to work on them. Also give me the option of melting parts to bring out some features like belts or folds in clothing.

Thanks for all the insights and perspectives, much appreciated.

Yeah, I think I come down somewhere in the middle of it.

For wargames units, where you're doing a mass of soldiers that fights in a block or line formation, mold lines bother me a lot less. And I think as I said the reason I never really noticed the mold lines with all my dwarves was because of the way I painted them. Layering colors really minimizes the effects almost to the point where mold lines aren't an issue.

But dang it when you use a primer color that's also your base coat, and then use drybrushing and washes (which is actually one of my favorite ways to do miniatures quickly), I discovered that I have to remove the mold lines. I'm doing a bunch of stuff for 40k and Kill Team and I'm using the GW colored sprays for primers. Well, unfortunately on space marines and Deathguard where you're using a primary base color to cover the whole model – mold lines show up like a sore thumb.

Luckily I have several Warhammer armies that are still only primed. It's not that bad to go back and scrape off mold lines and then put some primer over the scraped off areas.

Same for the 40k stuff. I was only at the colored primer phase so I can go back and remove mold lines and then hit them with a thin coat of spray again and I'm good to go.

I agree about the concern of messing up details. Davbenbak, you said it perfectly. The tolerance of them depends on how risky and difficult it is to remove them! There are some places on GW miniatures where the area is so fine that it's just not worth damaging the detail. It's better to just use layering to minimize the mold line.

I just went back and looked over my dwarf army and it's very interesting because as I said I didn't do any mold line removal whatsoever and they seriously look totally fine. On a tabletop and even up closer there's nothing you can see where you'd say ohhhh they're ruined because of the mold lines. They just don't register.

Rod: Mold lines on soft plastic figures are my bane. Can you give more information on the process you use? Specifically, what welding iron do you use? I have consistently had problems just using a knife as a blade is prone to gouges but can also leave small, hair like residual pieces that are super frustrating. I have had mixed success with fine grit model files- usually it doesn't work well on softer plastics.

Another thing I noticed about mold lines is that in some cases even when you scrape them totally flat, you can still see their "shadow" under the base coat.

I think it's because you're creating a different texture of surface from the surrounding plastic. Like the area where you scrape off sprue flash you can get a shadow.

But once you apply several layers of color those shadows become basically non-existent.

I also notice a difference on plastics when you use a brush-on primer vs. a spray primer over mold lines. Spray appears to cover mold line shadows better than brush-on, but I only have one individual experience of that so in a broader context that may not always be true.

On individual large character models like mounted models or large monster or military vehicle models, I take care to get mold lines down to being close to invisible. Same with gap-filling. On larger models gaps on arms and legs are pretty hard ignore.

But on rank and file troops in 28mm or smaller I'm satisfied with removing most of the mold line distraction, but not being obsessive about it. Bit filling gaps on rank and file, no way. Not nearly worth the return on time and labor!