@ArchangelPaladin: I was thinking of starting with Orks too, so thanks for the pointers about a starting list.
You'll need 2 sizes of plastictube for this conversion (the smaller should fit inside the larger snugly), apologies if it seems a bit simplistically-explained:
The Rokkits on the front of the Kopta have a vertical groove just before you get to the warhead/nosecone (should be just where the front mudguard-type-thing ends).
Saw off all 4 of the rokkits along this groove, leaving the stub/base of the rokkit still attached to the kopta.
Keep the warhead/nosecone bits, because you can use them for other projects.
Depending on how big you want the guns, the larger diameter tube should be either the same diameter as the base of each rokkit (which is still attached to the kopta), or big enough to slot over it.
Cut the larger tubing to the desired length.
Using a pin vice/hobby drill, drill various holes in the larger tube so it looks a bit more like an old machine gun/big shoota (leave a little unholed space at one end).
Cut a short length of the smaller tube and fit into the unholed end of the gun for the muzzle so that it sticks out from the larger tube (experiment with sizes to see which works the best), then attach the other end to the rokkit bases on the kopta.
If you are only wanting 2 guns, you could either:
Fill the gap between the gun and the bottom rokkit base with Green Stuff to make it look like a drum magazine.
Or, cut 2 lengths of the larger tubing the same length as the rokkit bases and attach them horizontally between the rokkit bases (so they're off-set, like the ones on the infantry big shoota's).
Then cover the hole at the tube end with flat plasticard (or just cereal box card).
Alternatively, you could repeat this and make the gun have 4 barrels to make it look more intimidating (although it doesn't change the rules, Orks are notorious for putting more gun barrels on things).
Urgently trying to trace any living relatives of Private Sam/Samuel "Jock" Wilson (Black Watch, No. 6 Commando, UK Army Service ID 2764432, died 10.06.44). Any info/suggestions gratefully received.
"Mockles! Pent on silpen tree, blockards three a-feening. Mockles! What silps came to thee, in thy pantry, dreaming?"
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