Ok, I've had a go at a quick tutorial. It's not the best, but I thought I'd try it out. Hopefully someone might find it useful or get some ideas from it. Here we go...
The gun shield. A few simple cuts to turn it from this...
to this....
I've glued a thin piece of plasticard to the back of it, behind the lower earthshaker cannon cut-out. I'll then fill the hole with green stuff to turn it into a more solid piece. I'll then cut a very slight curve in the top of the recently filled section to leave something like this....
(a bit of filing/cleaning is still required here)
___________________
Now the earthshaker cannon.
Take your standard earthshaker cannon....
And cut it thus.....
The bit circled also needs removing and filing/shaping a bit....
So that it all goes together like this.....
(again a bit of green stuff/ liquid gs filing and cleaning required. I wasn't as careful with my sawing as I should have been.)
__________
The siege gun.
Hit up B&Q. You're looking for these....
and these...
These pipe inserts probably required the most alterations. You'll see that the wider end has a kind of rounded chamfer. I wanted more of a squared off flange kinda thing. If I could have found ones without the rounded chamfer I would've got them.
In the end I used a bit of green stuff and a wrap of thin plasticard to square the ends off. Again, if you can find already square ended ones, it'd save a bit of work.
So I ended up with this....
(I've also glued on little bits of 0.8mm hex plastic rod, to look like nuts.....hopefully)
Then take the reducer piece, dismantle it, and cut it across the red line....
Then put the bits together. The sawn off narrow end of the reducer fits nicely into the pipe insert. The fat end of the reducer which screws off (there was also a little push-fit mechanism inside here that needed to come out) glues onto the back of the newly built up pipe insert to give you this.....
Then you put the two bits together.....
(You'll need to bore out the end of the pipe fitting here, or file down the end of what's left of the earthshaker cannon. Just a little bit.)
And now I have two.....
They aren't finished yet, but you get the idea.
Hopefully you guys find this useful.
Thanks
Alan