I had success back in 2009/2010 with just cones. I haven't gotten around to testing new shapes with the printer (completing ships takes priority). You could probably try to make the outlet more like a rocket diffuser. Something like this.
Maybe I'll give something like that a try. I'll see what the pumping capacity of this regular nozzle is first so I can see how much improvement I get.
Hmm, @Kevin P. I designed and printed a converge/diverge nozzle to test and I'm getting consistently lower outputs than a regular restrictor. Here's a cross section of the nozzle with dimensions. Got any clue why it's under performing.
How did the dimensions of printed part compare to your design? Did the throat and the OD come out the correct sizes?
And the work continues. Today was focused on getting the hull completely finished. That entailed filling a cavity in the stern that wasn't filled in with balsa when I blocked the stern. So I cut up a bunch of balsa pieces for filler... Then cut out a piece of balsa to go over top. Mixed up some epoxy then with chopped cotton fibers in it for filler and epoxied it all into place. Extra was spread around the stuffing tubes to give them support. That leaves the hull pretty much ready for water. There are a few more spots I'd like to hit with some epoxy, but I suspect I'll get that done tomorrow. Soon be time to put in the internal armor. Enjoy!
Worked on getting the guns mounted today. The stern sidemount is now solidly mounted. I got the bow guns' magazines secured, but I still need to fasten down the barrels. (when I decide how I want to do it) So here is how I mounted the magazines for the bow guns. I wanted to leave some room between the deck and mag caps so I can get my fingers in there to open them. So I cut some 3/16'' alum tube to act as spacers. They are very solid. The stern sidemount got a cable tie on the barrel to hold it in place. Turret still needs a little work to fit level on the barbette. And the underside showing how it's mounted down there. Enjoy!
I'm pretty sure I'll have the Kind Edward ready for the regionals, Marty. If not, I'll sheet the Suffren and be a French terror once again!
Internal armor is going in. Using dog screening provided by TyngTech. Thanks again, Steve! Installing it by gluing it to the deck rim. While waiting for the internal armor to glue fast, I worked on the rudder. Designed and printed one with fishtails. While the fishtails will probably be outlawed this year, I'll use them for as long as they're legal.
If you fatten up the leading edge, you can run the props at a higher RPM and that translates into more power when it turns.
Not interested in doing that. The fishtails and other rudder nonsense is on the ballot because people have taken rudder mods to the extreme. I don't want to be part of the problem, so I'm keeping it simple.
Every boat has a rudder. And these enhancements have proven to work hence the rule to outlaw. I find it funny at the need for a rule about shapes. Our boats perform way better than scale as it is.
Nice work! How did you make the props? And how is the rudder secured to the rudder shaft? I highly doubt the rules proposed are going to get rid of people playing with rudders to optimize performance, but if they strike a good balance that keeps the group mostly happy that's fine. Unless pretty much everything about a rudder gets dictated you're always going to have people playing with the design and tweaking as much as they can to make it just that much better. Some people (myself included) really enjoy that aspect of the hobby. The hobby is competitive by nature (you dont have to count/keep score to know who got shot up/sunk and who didn't) so having something a little better than the next guy can actually make a difference.
The props are built in the same fashion as the BC soldered ones, just they're all stainless and TIG welded together. The rudder shaft is bent 90* then inserted in the rudder to keep it from spinning.
Got the starboard side of the King Edward sheeted this afternoon. Should have the other side done by tomorrow, then sea trials.
