Like, cut the arms of person A and paste them into person B such that person B will now have 4 hands :) lol kinda funny. Thanks for helping!

Make everything on person A invisible, except the arms, hands, fingers.

Should you parent the invisible body A to the hip of visible body B, so the invisible body moves easily with body B?

Virus and Daz and maybe Sixus have 4-armed characters IIRC. The real way to do it is to have a new geometry file with all the groups properly welded and boned, but that's a tedious job, doing all the adjustments, renaming all the 3rd and 4th arm sections (collar to fingertips), new IK for the 3rd and 4th arms, etc. It's much quicker to parent the invisible body to the hip (or the visible body). Then all you have to do is postwork out all the places where the 3rd and 4th arms look bad on the visible collars.

Someone made 4 6 and eight armed characters for poser, there is a way to do it by editing the cr2, I don`t have a link to their site though (if the figures are still available).

Long ago I made 4, 6, and 8 armed versions of Posette. Here is how I did it, as best as I can remember.

Using a text editor I opened a coppy of the "P4 Nude Woman.cr2". In what I call the declaration block, the part between the two "figureResFile" lines, I made a copy of all the arm/hand/finger actors, and after the initial "l" or "r" in the actor name I added the number "2".

Then in what I will call the channels block, the part of the file below the second "figureResFile" line, I made a copy of all the arm/hand/finger actors, and after the initial "l" or "r" in the actor name I added the number "2".

Then in the "figure" block, the part below the channels block, I made a copy of the "addChild" statements for all the arm/hand/finger actors, naming them as in the above examples.

Finally i performed the same copy and rename process for the "weld" statements.

The result is a 4 armed Posette. Obviously you can expand the process to add 6, 8, or as many arms as you want, but it is a lot of work, and as you can see from the pic above the shoulders will probably need some postwork.

Attached Link: http://www.morphworld30.com/tutor.html

There is a tutorial "Making Extra Arms / Limbs in Poser" at Morph World, this is quite difrent from the method I describe in post #6, and probably easier (I haven't tried it my self). What you end up with is a cr2 containing two arms, presumably you could then parent this figure (Figure > Set Figure Parent) to the chest of your character.

That's pretty helpful! Thanks a lot guys. I am trying different methods myself at the moment :)

If you are using the mateo_sancarlos method (post #2), you can use the attached pz2 to hide everything except the arms/hands/fingers of the P4 or Mill figures (and probably most others). Note that in the Mill and P5 figures the collars (which are not hidden by this pz2) contain the breasts.

In this method you should apply the hiding pz2 file to your "Arms" figure, and only then parent the "Arms" figure to the chest of your main figure.

Save the attached file to a pose folder and give it a "pz2" file extention. The pz2 was made on a PC, it may need conversion for use on a Mac.

dalefindit