Upper/Lower Arm Swap

Any one have any tips on how to remove the lower arms from an O-Ringer so I can swap them with another set?
I've tried to crack the upper arm open with the chisel blade of an X-acto, but I think that I was doing too much damage to the part, so I figured I'd consult the pros here to see what kind of advice yall had to offer.

You are correct, using a chisel blade to crack open the shoulder joint for a lower arms swap can cause too much damage to the part.

Using an X-acto blade, score along the seam until the blade can get halfway deep, then get a small flat head screwdriver and using its edge, twist to pry the seam open. In some cases the seam will come apart easily just using the X-acto blade. Take care not to crack or break the shoulder joint completely off. Swap the lower arms out and try out the new set of lower arms you wish to use. It sometimes may require some sanding or cutting for them to fit correctly to function but make sure that the arms fit right before gluing them.

I hope that helps...

Awesome. Thank you, Livevil; when advice comes from a master like you, then I will definitely take and use the knowledge that you have passed on. Thank you for the advice, I'll try it tonight, and post pics when I'm done.

I do that version of the swap, as well as the rivet pop.

If you have a table vice, put the arm in there and with a framing nail(the very small ones) put it into the divot of the rivet. THen proceed to hammer it out. After a couple pops of the hammer it will come right out. Then all you do is the work you need to get done, pop it back together with a pair of pliers and then use a larger nail or equivalent and hammer to spread the rivet back out. Its really easy, and unless the elbow is cracked no real problems.

http://wiki.joecustoms.com/wiki/Lower_Arm_Swapping

There's pictures from a dio- tutorial I did on Joecustoms...

By working on the inside of the arm, any damage done is hidden in the figure's arm pit.