In the past, I have just painted heraldic or insignia type markings freehand, with varying degrees of success. Sometimes the slight irregularity of the end product had its own charm, but other times I was dissatisfied.
I wonder, has anyone tried using rubber stamps to paint symbols that need to be repeated across a large number of figures and that should be more or less identical? I know that rubber stamp carving kits exist, and believe that acrylic ink, or paint should stick reasonably well to them. I also realize that this would only work on relatively smooth, flat surfaces (if it works at all).
My short-term application for this is shoulder insignia for some GW space marines I expect to be painting soonish. I know that there are decals available for this purpose, but (A) I don't really like how decals look on painted miniatures, within my admittedly limited experience, and (B) I don't have any decals and don't want to spend money on figures I am mainly painting for practice. Rubber stamp kits aren't free, of course, but if it worked I would gain experience with a re-useable technique. It might also be useful for such thinks as vehicle insignia, shields, Sashimono banners, surcoats, etc.
Masking stickers might work for some things, although not for others (like this, for example). Also, I wonder how many times more than once a mask template could be re-used. I have no experience, yet, so I can't tell.
Is this something that has been tried or is it so brilliant(ly stupid) that it hasn't? That seems very unlikely, but I haven't found any prior info about it.