That's a fantastic idea, TheVoid. I was under the impression that the secondary weapon system of the HH took the place of the gun drones, and it never occurred to me that you could buy them for it because there's no room! I might have to do that on one of mine.

And anything that advances the cause of RE magnets is good by me.
I've got some more work done on my Hammerfish now, after getting sidetracked for a while with work and painting.
First off, I decided that I was going to fit 1/4" magnets to the inside of each primary weapon, and mate them to a 1/8" magnet on the turret mounting bit. The latter part was easy enough to accomplish with a drill and a drop of superglue.

I glued the bit down to the turret, as I found during testing that the pull of the magnet was stronger than the fit of the bit. Besides, with the method I'll be using I wouldn't be needing to swap the bit out.
I mentioned that I was going to do some detail scratchbuilding on the inside of my RG. In addition to designing a level and sturdy mount for the magnet, and using brass rods to straighten the warped parts I got, I wanted to bulk up the "vent" parts of the barrel. While I'm sure it looks just fine at tabletop distance, I was unhappy with how hollow and unrealistic it looked, and wanted there to be some internal structure to the barrel for those who cared to look closely enough. So with several different kinds of plasticard strips and a 1/4" RE magnet in hand, this is what I came up with after a lot of cutting and filing.

Most of it is just to provide a solid look to the barrel and the linear accelerators, with the narrow chamber down the middle through which the munitions and slugs pass. I drilled a small hole in the back end so that there's actually a place from which they emerge. I'm probably going to prime and paint the internal parts before assembly, so that I can add some minor details.

On the other half, I cut a flat piece of card and glued it to the inside of the part, then glued the magnet on top of it. When I tested the fit out on the turret, however, I discovered a problem: magnet or no, the RG was still going to droop because of its frontheaviness, which wasn't helped by the brass rod being used to straighten the parts. There's a slight gap on either side of the mounting bit in both the IC and the RG that allows the guns to elevate--and droop. The solution: more plasticard!

This picture should probably be self-explanatory.

The only hard part was the filing necessary to get the fit just right. Which it is:

The railgun remains perfectly straight now at all times, stays on even when turned upside-down, but will come off with a slight tug. Actually, picking up the railgun lifts the turret right out of its socket.
Next was the ion cannon. This was much, much harder, because of the uneven internal structure of the parts. Obviously, GW didn't design them with what I'm trying to do in mind.


Correctly mounting the magnet required a three-part bulkhead, one of which did double duty filling a gap in front of the mounting bit to prevent the same kind of droop the RG suffers from. This took an absolutely ridiculous amount of filing and sanding to get right, but it was worth it in the end.

Here's a better look at the assembly. Now, most of you will probably want to just jam a wad of green stuff in there and call it a day, because this was a cast-iron PITA. I did it mainly because I wanted to challenge myself and improve my scratchbuilding. But it works:

Yes, you will notice that I still haven't gotten around to converting the other half of the IC to use a transparent blue rod.

What I have gotten around to is assembling some of the rest of the vehicle. I'd been apprehensive about doing /any/ gluing until I had a specific plan, because I have some pretty ambitious ideas for internal detail and some of them require very careful thinking about what order in which to do things.
I would like to mention a few tips, though--I found that if you want to model the landing gear up, you're going to have to cut off the struts. There's simply not enough space under the seats and in the nose recess to do it otherwise. You can do this however you like, but I carefully sawed them off as neatly as I could--figuring that they're nice bits of detail that might come in useful for something else.
I also found that the thin plastic lip that runs around the floor of the 'fish to show you where to put the seats is a bit too long. In order to make the seats fit properly, I had to carefully slice off a tiny bit along one of the tile seams in the floor.
Here's a picture of both:

Notice the lip of plastic I'm talking about? Carefully cut off the part that overlaps the crack in the tile, and you're golden.
Hope this is helpful. Will post more as it comes.