I will be starting my 'gnat killer' build soon, I chose the Bellerophon class based on gun arrangement and low popularity (I like to build less common boats). Bought a Dreadnought hull from strike since they seem close enough. Float tested it last night, finally a boat that fits in the tub! Looks like I'll end up around scale weight, to get 3/4" freeboard on the aft deck.
Good idea calling it the 'ghat killer' and not something else. I called my boat the 'nassau killer' hoping it would make it better, but it just seems to make it worse...
The Dreadnought and Bellerophon hulls were almost identical. I've got the Anatomy of the Ship book on Dreadnought and was tempted to build one but like the looks of the Bellerophon Class better.
I liked the look of the Bellerophon better as well, along with the nostalgia from the 'Lars Chronicles' from the pre YouTube days. It should be an interesting boat to battle. I got the hull marked last night, and cut today. On these builds I'm trying to do a better job of keeping the red area limited to just over an inch, so I measured down 1.25" from the center of the waterline from the float test to mark the bottoms of the windows. Bow, two 3/8 ribs Stern Holes drilled About 50 min later, hull is cut out Removed tape Rib thickness was OK Project will be on hold due to the Hagerstown battle next weekend, I should be back to work on it in two weeks
Ah, the Lars chronicles, brings back memories. I should call him sometime and see what's up these days. Bell is a pretty boat, hope that you enjoy her.
Resurrected from page 3 of the build threads. My two early battles this year re-inspired me to work on this build. Local allies need small-boat help Basic layout to see how things might fit Got nice new props, very glad that Chris put together his site. Blades might be a little thinner than prop shop, but overall very nice Drive motor options. I've had the 555's around since way before they were cool ;-) The plan is to use the little brushless, save the weight for an extra gun/solenoid. I am going to try out Steve's non-flex coupling Prop shaft alignment. Mark shaft holes. Goal is to get the pump between drive motors to keep the fore/aft distance in check Prop template to hold shaft ends. Start with paper to get shape, then transfer to scrap wood Cut holes and test alignment. Rough estimate for first holes, then adjust as necessary. Will fiberglass over the whole thing so large hole is no issue Side view ish. Still working. Motor mounts will be aluminum angle pieces. Will need to make the mounts then test with stuffing tubes, then epoxy motor mounts in place, finally glass over the stuffing tubes
Not to hijack Kevin thread, but mine would not fit in the tub. I had to get a test pond as I call it, wife keeps insisting it a kiddie pool. New Props also.
Looking good Dave, I'm jealous of your test pond, I don' think I could pull that one off in my apartment haha Made a little progress today. My work hours have gone up recently which has cut in to my normal build time. Made the motor mounts from aluminum angle pieces. Attempts 2 and 3 were successful for bold hole spacing. Other view The elevation of the motor for that shaft length was too high, so I decided to drop them into the hull Holes for angle and extended shaft holes for clearance Test fit. Better on shaft angle but not as shallow as I'm used to with the Traxxas gearbox I've used on the last several builds Side Mounts will be flush with hull on underside, will just take several epoxy jobs to get right. Next steps will be cutting stuffing tubes, putting in bushings, then epoxying in the motor mounts. Once they are solid I will finish around the shafts, will also add struts, then remove the motors and finish epoxying motor mounts from inside and outside of the hull
Epoxy is more of a verb here. I use a good deal of filler (microfibers) for situations like this, as well as strips of fiberglass mat, pretty much rebuild the hull around the shafts, tried and true
Yeah fore/aft distance will go at a premium on this build, I will check options/verify distances before setting the mounts
If I were to sully myself and run an outrunner , I might consider a mount such as this. A bent aluminum plate installed from the outside fitted through a slot in the hull. This would give the lowest possible mounting height and provide an excellent heat path for cooling.
Cooling happens when you battle naturally, others may think that water doesn't slosh around but they may be wrong.
Agreed, but with outrunners, the direct metal to metal heat path from the wire coils is via it's mount. Running the mount to the outside water can only be a good thing. My Barham has keel coolers and there's times when pulling it from the water that they're warm to the touch, so the idea has merit.
Yeah, the efficiency of brushless motors ticks me off too. I considered a through hull mount like that but given the no-flex alignment on the coupler I suspect that getting the right motor position and multi-axis angle exceeds my build capabilities. So instead I decided to subtract hull and reapply it around the motor/shaft assembly in liquid form. Motor height will be the same or better than proposed mount, I will probably glass over the outside of hull to fair it in and for better structural properties, not too worried about cooling but agree that the outside plate looks good online
I was going to use brushless in my new Bismarck, but decided to try some Brushed crawler motors I had in my storage drawer I had purchased for convoy ships. I installed 3, 80 turn crawler motors in the Bismarck with a 2:1 gearbox, on 10 volts system. Motor are only $9.99 each so nice and cheap. Its fast right now, but is only drawing 5.4 amps at full speed running the 3 motors when I hold it still to read the amp meter. Stops in about 4 inches, has a 2.4 in center prop, and 2, 1.4 in outer props, with no drag disks. Once I slow it down a little to get it on speed, I suspect it will be less than 5 amp draw total, so even brushed can be efficient, if set up properly. 5 amps to push a Bismarck around is nothing. and being 80 turn motors, high torque, low current draw, and after running it for 20 minutes, only the center motor was a little bit warm to the touch. I'm happy that rule passed that all the motors have to be running in both directions. The outer prop opposite from the turn pushes the boat forward, and the other outer prop on the inside of the turn hits the rudder, adding to the center props, prop wash assisting the turn. Boat turns on the B turret, and changes direction very fast. I like Steve's suggestion on the plate through the hull, that would really help with cooling, if you did not like it sticking out on the other side, it could be recessed into the hull and glassed over. have you tried running the motors with a prop on them in the water? Just to see the current draw?
Sorry to go on a tangent here, but would either of you mind explaining how to properly test the current draw? should I put the test leads on the motors?
oh good, thanks for the tip on hardware, but where precisely do you attach the clamps? on the motor leads or on the line from the esc?
