Custom Armor Model, there is no clear answer.

So I have been messing around with a custom model for a helmet, but every time I build outside the normal armor boundaries I get random artifacts.

Does this mean that you can't actually have a custom armor model?

I have look around for answers via mcreator search, but the only solutions are people who know what they are doing fixing it for them. Or coding for that specific model.

These do not really help me at all.

Is there a solution that does not require custom coding?

Is there a guide on this?