Here's a little mod I did that I thought I'd make into a quick tutorial. I love Prime's swords, but I didn't like how they got in the way when I tried to straighten out his arms. So I did the following mod that allows them to go off and on, but loses the spring feature.

Just like in my ball joint wrist tutorial, I recommend doing one arm at a time. First you'll need to unscrew the forearm panel:




When you pull it off, you'll see the spring and post of the sword:




Just pull the sword right out and set it aside for now:




You'll need the Lego pieces shown here. A bar with at least two holes and a post with a peg on each side:




Cut the bar piece down to look like this (top view and side view shown). Leave a little bit extra because you can always shave it down a little more as you go:




The piece will fit right into the area the sword post occupied. It won't even need glue or anything to secure it in place:




Top view:




Here's a shot side-by-side with the forearm panel that was removed earlier. There's some plastic on that panel that sticks out and goes in by the fist. This will fit right over top of where we cut the LEGO piece:




Screw the forearm panels back on and you're done with this part! The LEGO holes should line-up right through the forearm holes:




Here are some pics of the swords, one before and one after modification:






First, remove the metal pin and spring from the sword with a pliers:




You won't need them anymore for Prime:




Cut the post down about as much as shown here. Again, you're better off to leave it a little extra long at first:




And cut the peg as shown, leaving a little extra:




Then drill the hole in the sword post bigger until the cut end of the Lego peg can fit in. I just used drill bits, but my hands took a bit of punishment. I like to drill a little bit bigger at first and gradually use larger and larger bits. The orange plastic will be very thin by the time the hole's big enough for the LEGO piece:




Keep drilling and cutting both pieces until the peg fits all the way into the post as shown, with the peg's mid ridge touching the orange plastic. Also, while doing this, keep testing it in the hole on Prime's arm. You may need some needle nose pliers to pull the peg out sometimes when it sticks in Prime instead of in the sword:

When everything fits, put some superglue around the edge of the black peg and push it into the sword's post:




You may need to use some clear finger nail polish or other tightening agent to keep the sword from flopping down. The first sword I modded needed some polish, but the second one was very tight right away.

That's all the work involved. Next, I will show how you can use MechTech weapons in those holes!

* * * * *

To use a MechTech weapon in place of the sword, you'll need another LEGO bar with holes and another LEGO peg, but this time the peg needs to be double length on one side of the ridge:




Push the short end into the hole into Prime's forearm:




Put the MechTech weapon peg into one of the holes of the LEGO bar:




And then push another hole of the MechTech bar onto the peg sticking out of Prime's forearm:




You can also use some MechTech adapters to REALLY arm Prime!







I hope this was helpful. Enjoy!