I second Mike's comment. I have a small gear pump that will prime easily from 20" above water level. The only problem is that I'm not sure that it will pump 1/2 gal/min, so you may need two. It was approximately $18, so you can almost get two for the price of a normal pump.
Mike, You are absolutely correct (and brilliant)! I've battled treaty enough, that I thought positive displacement pumps were verboten for Battlestations as well. Using, say, a fuel pump means that I would not have wasted space in the bow. I would just need to find a fuel pump with a flow rate of 2000CC (or 2L AKA ~2 quarts) per minute at 6V. I'll just hold off blocking in the bow until I have a pump that will work, and finalize the mounting. Again: Brilliant! Curt, Thank you! Mark, Thanks for looking that one up. I'll just have to do some digging for one that fits the dimensional restrictions I have.
Ja, we limited the output, not the means. I will award the Tugboat Technology prize ($0.50 + a wad of masking tape from the shop floor) to the first person to battle using a magnetohydrodynamic pump that produces the legal output flowrate
Clark, With Mark's engineering skills and Matt's penchant for HUGE ships, I would not be surprised to see one in the future.
That pump looks exactly like the one I have. So I pulled mine out and did some tests: 1.2 Amp no-load current 6.6 volts, 3 amps, 8" of 1/8" hose on the intake, 4" of 1/8" hose on the outlet: 55 seconds to move 4 cups. 6.6 volts, 3 amps, 4" of 1/8" hose on the intake, no hose on the outlet: 52 seconds to move 4 cups. Now mine might be a little off performance. It is definitely no more than a 6v motor, but mine has some time at 12v, until the horrible sounds convinced me that it would never work at that voltage. It smells funny too
Awesome, I just ordered two. $28 inc shipping... One should be a viable solution for sub-2500 ton ships running 6V.
I have just passed a very important milestone (for me) in building this hull: Blood has been shed! A pair of old sprue cutters went into the meat of my palm. I can now rest easy knowing Poseidon has had his sacrifice In other news, I cut the riser tubes for the re-worked cannon breech, blocked out and sanded the stern to shape, installed stuffing tubes, and did some other boat related things... Mark, By the dimensions listed, those appear to be 550 sized motors. Is that correct?
I'm fine. The wound has already scabbed over and doesn't hurt any more. Breech work on the mains is complete. They will be an Arizona breech with Indiana barrels so I can adjust depression accordingly. The mags will 1/4" ID vinyl hose with an endcap. The hose will be held on with spring-clamps and E-6000 to the leads for the mag-to-breech tube and endcap made out of 9/32" OD brass tubing. The endcaps will be a Watts inline 1/4" compression fitting drilled through 1/4" and one side drilled to 9/32" for the tube. The mag will be mounted to keep it above and sloping towards the breech, I have an idea for fitting in secondaries--Madness? Perhaps...
Secondaries are a no-go. It also looks like I will be able to fit in the standard BC micro pump if I can make a new outlet with an elbow. I had some inspiration on the superstructure and will be following the method Mark did on his Kearsarge's turrets. I do not have access to a laser cutter, so I drew out level one by hand on four sections of 1/4" ply, cut the outline for each piece and cut 1/4" in for a hollow space. The pieces got glued together and then sanded even. Level one will be sheeted with 1/32" ply to keep it smooth.
The hull, deck, and level one are now done. I still need to do some blend sanding on the sides, then I am ready for fiberglass.
Thanks Clark! It means a lot when builders with more experience (and whose work I admire) compliment my work.
If you look carefully, you can see rib 19 is very close to the stern. The vertical portion of that rib will be cut out and a new false vertical section made of 3/16" will be inserted halfway between rib 17 and the stern close to where rib 18 falls in the plans (even number ribs were skipped for this build).
Got some work done today. Mainly the little things that seem to add weeks to a build with no apparent progress. I did manage tomake a new pump outlet, mags for the cannons, and finialized my layout. I even have TWO positions I can put the ESC! Though I keep going back and forth on the motor mounts, I thik I will just want to drill out a piece of 1/8" ply and attach it to a rib.
The rudder is made and the post is in. This was my first brass rudder and it didn't turn out too bad. I switched to a different solder and that has made all of the difference in the world. I also weighed everything for the first time: 5 lbs 13.5 oz. My target weight is 8 lbs 2.72 oz or 8.17 lbs according to the ship list. If I add in 3.5 oz for CO2, that leaves me with 2 lbs 1.72 oz left to work with. I should be good to go and might even have to add in a little ballast I forgot to mention that yesterday I charged my CO2 tank to 3.25 oz and performed a test firing on one of my guns. for the purpose of this test, I activated the MJV-2 manually. Despite a leak in my ad-hoc pneumatics, I got off 70 shots before the gun started to sound anemic. Accounting for both cannons and a loss of CO2 for the SMAV-3 to MPA-3 vent, I should get 35-40 shots off of a full load of 3.5 oz. My mags hold ~45 rounds as a result of the test. An unexpected observation: very little gas actually goes out through the mag tube at the breech in an Arizona. This is a more efficient design than I thought.
So a very serious question: Should I go with the 1 1/8" four-blade high pitch props, or the 3/4" three-blade low pitch props. I will be using 6V Johnson 380's like the ones BC sells for cruisers in a direct drive setup. My primary concern is turning over starting/stopping so I am leaning towards the 3/4", but I wanted to get some input.
