@Vlad,
This was a "custom", in which I paused the printer during a build of tall masts and snipped one out of the matrix. I would liken the procedure to getting a fly out of a pan of freshly poured cake batter just as it was set in a hot oven. Not recommended.
These can be made as a batch of "specials", now that we know how high to go. Better than cutting down a full-sized mast, which can be tricky.
@All
The 3DModelParts material is a customized acrylic blend; it results in a material which is still somewhat brittle, just not quite so much as most hobby resins (epoxies, polyesters, etc). This material has some "give". You should be able to drop a cage mast (or any of our parts) off a table and have it bounce without breakage. You then might not be able to find them, which is one reason they're day-glow orange. That, and the desire to use a complimentary (contrast) color to aid in best bringing out our battleship grey and blue paints...
The forming process is more similar to making PE than either resin casting or injection molding. But ickier. There can be a slight residue, even after our cleaning, which is why we recommend a rinse with paint thinner or alcohol (the parts, not you; with rubbing alcohol, not beer) to clear any residual waxiness. Although not porous, the material has a slight microscopic "tooth" to it, and takes any hobby paint well.
If there's enough interest, masts for the CC-1, BB-49, and other classes can be printed as sets. Note that Brandon at FreeTime has a range of sizes, by ship class, going from CO-class all the way back through re-fitted predreadnoughts suitable for most of the kits out there.
As for weapons for the battlecruisers, I haven't gotten to a 6" gun yet; there's a lot in the pipeline, including that 4"/50 twin for a flush-decker...
Regards,
-Carl