There seems to be a growing trend for some to have their minifigure customs printed instead of using decals, paint and whatnot. Anyone know how this is done? Is there a home based printer that does this or do custom sellers farm the parts out to shops to have it done?
Just curious, not looking to start my own shop

You can either:

1) Purchase a small print-pad machine and spend a crazy amount of time making the copper plates for each 'color' to be printed onto a minifig. The equipment will run you somewhere around $1,500 and then you'll need the plates for etching and the ink. The largest drawback is the sheer time it takes to etch each plate. Christo and Citizien Brick use this method.

2) A UV Sublimation printer is much faster and can pretty much print 10 figures for every one that is pad printed, assuming you know what you are doing. Of course, with time savings comes an increased price. These printers sell for anywhere between $25,000 and $30,000. They are really meant for small printing/marketing busineses, not hobby. This is the machine BrickArms uses to print on their products (although I do not believe they have a UV model).

-A

What about silk-screening?

In a merchandising workshop I have worked with it on cloth, paper, mugs and glasses, and its also used to print on lighters and pens, that's plastic and small enougth to be compared to LEGO pieces. It's not very expensive, but requires some knowledge, practice (difficulty increases with the numbers of colors you want to print together in the same design piece), workspace, and tolerance to the chemicals necessaries to prepare the inks and to clean the utensils.

It never occured to me to try to print on a LEGO piece when I had the chance working there, the idea just gives me an impulse to do so, but I don’t have the equipment nor the space, and neither the time (for now)!

It's comparable to Print Pad.

Print pad you burn each design in each color onto a plate, then dip the plates in ink and apply them in proper order.

Silk Screen you burn each design in each color onto a screen, then apply the ink to each screen and apply them in proper order. The machine for this costs $20,000 and it takes approximately 30min to burn each 'screen'.

Either way it takes a significant amount of time which is why most people who do this require substantial minimums.

With that said, some places like Custom Ink are lowering the minimums for shirts...

-A