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Hi I found this PDF on Graupner motors. Also the Hobbyking site shows the specs on a large number of their brushless motors. I am looking at replacements for two Graupner speed 600 7.2 volts for a mate. I found a D3530/8 1700kv on Banggood with the same 5mm shaft and more grunt, less weight(74 grams against 192 grams)and about a third the price!!! I am going to install one in a Sea Commander(34") with a smaller 2 blade 32mm CNC prop on 3S Lipo 3300mah to test it out. Canabus
Hi I use 4mm stainless steel shaft with a brass or roller bearing at the motor end and a Teflon bearing at the bottom. Grease I use Dow Coring Molykote Compound 111. A squirt in each bearing and install the shaft with a finger over the inner bearing( the air escapes via the oiler tube) and cap off the oiler. I the picture is the shaft support on my Huntsman which is a slide fix for the prop shaft tube. Canabus
Hi All I am using Hobbyking 3639-1100 and 3648-1450kv motors in that size boats(Sea Commander, Precedent Huntsman and SG&K Gentleman's Runabout). 60 Amp ESC with either 3 or 4S Lipo batteries. Props 2 blade 40mm 1.4 or 1.6 pitch. The motors are a straight change over and the only change to the ESC is the low voltage setting for the 3S and 4S batteries. Canabus
Hi BigAlio Thank you for the you tube link, some very nice boats. The double seat SG&K with the motor up front was especially interesting. My single seat model preformed spot on straight up. I would drop the sides down from the bow and add in some hidden spray rails, has it is a very wet boat at slow speed and cornering.
Hi Andy I use the Hobbyking Low Voltage Alarm(black) part no. Alarm-Voltage. These monitor the total voltage and each cell voltage with a digital read out. The connector from the battery, the black wire is to the left looking at the front. Banggood have one without the black which does the same job.
Hi Jarvo I also have a 46" Fire boat, but, it's only single shaft as I am the second owner. I am using a L5055-700kv, 4S 5800mah 40C Lipo, 60Amp esc and a 2 blade 52mm prop. In a twin setup a pair of Hobbyking 3639-1100kv on 3S or 4S batteries with 60Amp ESC's and 3 blade 37mm props and if you wish more speed a straight change over to the sister motors the 3648-1450kv but you may have to drop the props back to 2 blade 40mm. Canabus
Hi All The boat is not a Sea Hornet which is 642 mm long and the stern is totally different, also, the rear cockpit is to far forward. It is still a nice boat and would look well restored. I have the original plan and boat. Canabus
Hi pilot ChrisF is about right with the overland, but, if it's Hobbyking stuff. A Turnigy L5055C-700kv 1600watts on 4 to 6S with a 100Amp ESC which will handle up to 6S. I am starting with a 2blade 52mm CNC prop(377000019) on 4S. The 3674 1900kv is more for a high speed race boat. Canabus
Hi Guys I have a PDF copy of the original Aerokits plans, but, it has no frames. With a few measurements I think the frames can be got for these plans. I did this on the Sea Hornet plans. So if you guys require the original plans PM me. Canabus
Hi Andy Slightly more power with a brushless motor is a no go!!! Brushless motors the same size are far more powerful !!! But, the about same RPM a Turnigy L5055-700kv(500 rpm more on a 4S(14.8 volts) Lipo battery would be a good replacement. Mind you at 1600 watts( about 2 and 1/4 HP) these will used in a large boat like a 46" Vosper Crash Tender or a 46" Sea Queen!!! My move into brushless motors I have found that they are 7 to 10 times more powerful and equal to, if not better than the old IC motors!!! My Sea Hornet, Sea Commander and Huntsman run brushless motors . My Crash Tender is getting the 5055 motor, so it will be interesting to see what it will go like!!
Hi All I was told to use plumber's tap silicon grease, which I have used for 3 years and only regreased once each year. I have added oiler/grease tubes to my rudders as well. Also you can get a silicon spray like WD40, but, with the silicon spray it crawls up the shaft. With the shaft out and the tube cleaned out(pipe cleaner works well for this) a shot of silicon grease in each end of the tube(only small amount). Hold your finger over the other end and install the shaft, this stops the grease coming out as the shaft comes through. A shot of silicon spray down the oiler tube and seal silicon fuel tube sealed off at one end. Canabus
Hi Pilot I have the Precedent Huntsman 34" hull with the 3648-1450kv, 100 Amp car ESC, 2 blade 40mm 1.4 pitch CNC prop and at present only running on a 3S 5800mah Lipo. I am still working on the cabin and that windscreen. Installed the front, rear, toilet and kitchen windows and frames today. The boat is very quick in the 35-40KPHour mark, so it's not slow. Canabus
Hi Pilot If you are using 540 can size (35-36mm brushless motor) a 3639-1100kv 800watts, 3648-1450 1600watts or a XK 3674-1900 1769 watts. All run on 100Amp ESCs, but check the maximum voltage they handle. I use car ESCs with the electric fan on top because they run cooler at slow speeds and no water plumbing required. The same with the motors no cooling. Props for these motors 37mm 2 blade or 40-45 mm 2 blade. If you go for a larger motor for a larger prop, a L5055-700kv 1600watts same ESC, but, start with a 2 blade prop about 52mm. Battery a 3-6S 5800mah or more with a C rating of 40 plus. I have used the 35mm motors in 34 to 40" boats, but, for my 46" Vosper Crash Tender I am going to the 5055. To large a prop will cause over heating of the ESC, battery and Motor. A in line amp meter(Hobbyking 9598000004-0) is the one in use. It reads the maximum amps, so for run speed amps slow speed up to maximum as a hit the throttle hard will give you maximum amps. Canabus
Hi Hope you can get spare flex drive cables as Hobbyking do not sell spares !!!! Mine is sitting in bits and the boat is getting converted into inboard with a 4mm flex drive with the original motor or the upgrade motor a 2836-3700kv on 4S. Canabus
Hi What type of props are you using(size and number of blades). I see your basic problem is under powered motors and a very heavy battery. I made the big switch over three years ago from brush to brushless motors and to Lipo batteries. With the help on the forum and club members it was a learning curve, but, I would not go back. A 5800mah Lipo battery is in the weight of 450 to 570 grams and would give you a good 1/2 hour run time. A good balance charger and safety bag are the main requirements, also maximum charging for the 5800mah battery is 5.8 Amps(same as the old Nicads). Also a low voltage battery alarm. Your 600 motors can draw up to12Amps !!! Replacement same size motors for your mounts would be 35mm brushless motors, but, you will require two ESCs with a Y connector to run on the same throttle channel. Replacement brushless motors are far more powerful e.g. a Hobbyking 3639-1100kv with a 60Amp ESC on a 4S 5800mah Lipo Battery is 800watts and with two in your boat is 1600 watts!!! Your old motor would in the 100 watt each mark !! I have the same size crash tender, but, with a single brushless motor. I have all the order numbers for the motors etc. and a setup the ESCs if your require. Canabus
HI Richard I drop my prop angle to 9 and 1/2 degrees on my Precedent Huntsman 34" after removing the old IC motor. Running a 35 mm brushless motor on 3S and it's very quick!! More a speed motor than a motor cruiser. Canabus
Hi Capt Larry I have used the Turnigy and Compact Zippy ones from Hobbyking with no problems for the last three years. Note only charge them at the maximum current equal to the battery capacity, eg 5800 mah = 5.8Amps. Lower Amps is better. Canabus
Hi I use a Turnigy 180Amp watt meter and power analyzer(part No.9598000004-0) 0-60 volts , size 85 x 42 x 25mm, 82 grams. Requires your battery connectors. Use it in line with the main battery on board the boat. We used it on my mate's Spearfish and got 72.88 Amps on a brushless motor at 37 KPH. Canabus
HI AndyG009 The steep angle was to get the diesel motors into the boat. On my Precedent Huntsman I decreased the drive line angle both at the prop and motor ends. The 35mm brushless motor was less diameter than the flywheel of the IC motor. I can still fit a 45mm prop with 5mm clearance, but, using a 40mm 2 blade. I quick test on Saturday and the boat has no problems with prop torque at full speed. I made a little larger rudder, mainly a bit deeper. Rudder control is very good. Canabus