Blog

Fitting sub decks and Sea Trials

The fore sub-deck is glued onto the bulkhead assembly, prior to fixing it into the hull. This is a straightforward operation, but some sanding of the sub deck is needed, particularly around the bow. With short strips of square balsa glued onto the hull sides between the deck beams, to support the edges of the foredeck, the whole unit was again dry fitted. Happy with the dry fit and armed with various clamps and clothes pegs, I glued the assembly into place. (Once again, apologies for the lack of photos as I did this before deciding on doing the blog). Before fitting the aft sub-deck, I cut out an opening to get to the tiller if necessary. The opening will be disguised later in the build. Sea Trials. I decided on , as the weight would go a long way towards ballasting - she sits very low in the water. Jotika advised 60mm 4 bladed props, which were duly fitted. As I have already said, I use a Taranis radio and this has the advantage of being able to set up a differential drive between the motors and rudder in the transmitter. As you can see on the video, she turns in her own length. You will also see from the video the 'deck cargo', or cardboard box full of the white metal fittings. This gave me a better idea of how much more ballast I would require for the finished model. I did have a scary moment when the 'deck cargo' shifted and she took on an alarming list to port! I thought I would be a contender for the 'Titanic Award', presented annually by our club for the best sinking. However, with nerves of steel, I navigated her safely back to the slipway. I was most pleased with the way she handled and moved through the water. The motors and props supply more than enough power and she will require very little more ballasting.

5 years ago by cormorant

Blog

New drive Train and Oiler

Most of this actually took place last August / July! Regular readers may have seen that when Dad built this boat in the 60s he put a Taycol Target field motor in it. About 25 years ago I put a Decaperm and 'modern' transistor ESC in her to provide forward and reverse. Performance was sedate to say the least. I have since modified the Taycol (see below) so it can be run forward and reverse and decided to put it in an ancient Billings Boats Danish fish cutter (Gina) that I inherited from an Aunt. The cutter is badly in need of renovation (see pic 1) and the Taycol will be more suited to her performance requirement! On advice from Canabus in Hobart I obtained a Propdrive 2830 1000kV brushless motor, appropriate ESC and a 35mm 3 blade prop from Raboesch. Pic 2 shows the old and new motors. Next step was to trial fit new motor mount, coupling and prop. Pics 3 &4. While doing this it became obvious that a new shaft was in order, as mentioned in last update. Soooo, - appropriate stainless steel rod, thrust washers and set ring were acquired and back to the workshop. After cutting to length to accommodate the new coupling type a 3mm thread was cut a the prop end. At the inboard end I milled recesses for the grub screws in the set ring and the coupling, pics 5 - 7. I don't like to just file(or even mill) flats for the screws cos they have a tendency to slip and work loose😡 Trial fitted the new shaft and found I'd boobed a bit with the measurements and need extra thrust washers to make up the difference. 😲 Pic 8. No sweat, they came in a pack of 50 anyway😊 You can also see in this pic that I decided to fit an oiler pipe while everything was in bits anyway.😉 To solder it on in a cramped space without setting the boat on fire 😡 I packed a wet rag underneath and used a gas Kitchen Torch! Known as a 'Gas Gourmet Burner'. Yep, those handy little gas torches like your Missus uses to melt the brown sugar on her Crème Brûlée!! So do I, delicious 😜😉 The torches are not expensive, small, very handy, refillable with lighter gas and can be adjusted to a very small hot flame. ideal for this job. See pics 9 & 10. Pic 11 shows the new motor & mount, shaft and coupling all trial fitted after using a brass alignment tool I quickly made up on the lathe. Pic also shows the trial electrical installation after cleaning up the 'machinery compartment' a little and painting with silver Hammerite. A Quickrun BL ESC is sitting in the bottom in one of the trays my Dad originally fitted for the 2 wet cell (very wet!) 6V . The home made board on the left carries the battery and ESC connectors, main ON/OFF switch with LED, blade fuse holder with a 20A fuse and a green LED which tells me if the fuse is blown! Stuck on the walls (OK Bulkheads!) with so called Servo Tape are a 6 ch Turnigy iA6 2.4Gig RX and the arming switch for the ESC. Battery compartment is sized to fit 2S and 3S hard case LiPos. For trials I can fit my Wattmeter forward of the switchboard and splice it into the battery supply using Tamiya connectors. Might change these to XT60s later if current drain is more than 12 to 15A. All for now, all this was pulled out again preparatory to cosmetics on the hull, decks, cabin roof and walls inside and out. But that's another chapter so, 'Tune in next week, same time same channel when once again it's time for 'WHAT DO YOU MEAN BUCK RODGERS IS APPROACHING!? 😁 Or 'The Saga of the Cabin Roof' 😉 Cheers Doug 😎 BTW: After drilling the shaft tube for the oiler pipe I flushed it out with light machine oil (pumped in from a big syringe) and shoved a few pipe cleaners through (rotating them on the way) to remove any remaining drill swarf!!

6 years ago by RNinMunich

Wiki

Lead Acid Battery Charging

NOT from me (RNinMunich)! I just edited it to delete a previous comment of mine! should not be discharged and kept charged up as much as possible. Discharging these batteries will reduce their capacity. if they are kept for any length of time without a charge, they will not charge up again. To charge up these batteries use the same formula. However can cope with heavy currents and it is sometimes a good idea to charge them up with a higher current. Now and then charge them up with double the current as usual and for half the time. So for example, a 5000mA/h battery, should be charged on 1 Amp for 5 hours. Winter Storage To ensure they will be fine when next used make sure they have a top-up charge every couple of weeks. Half the length of time of a normal charge. DO NOT HAVE THE BATTERY ON A CONSTANT TRICKLE CHARGE! Large 12 v (e.g. old home security batteries) have a time constant of approx 4 hrs so need to be charged 5 x 4 hrs = 20 hrs. I leave mine on overnight which usually does the job, offload charged battery volts are approx 13.8 v.

5 years ago by Tall Paul

Wiki

Lead Acid Battery Charging

NOT from me (RNinMunich)! I just edited it to delete a previous comment of mine! should not be discharged and kept charged up as much as possible. Discharging these batteries will reduce their capacity. if they are kept for any length of time without a charge, they will not charge up again. To charge up these batteries use the same formula. However can cope with heavy currents and it is sometimes a good idea to charge them up with a higher current. Now and then charge them up with double the current as usual and for half the time. So for example, a 5000mA/h battery, should be charged on 1 Amp for 5 hours. Winter Storage To ensure they will be fine when next used make sure they have a top-up charge every couple of weeks. Half the length of time of a normal charge. DO NOT HAVE THE BATTERY ON A CONSTANT TRICKLE CHARGE! Large 12 v (e.g. old home security batteries) have a time constant of approx 4 hrs so need to be charged 5 x 4 hrs = 20 hrs. I leave mine on overnight which usually does the job, offload battery volts are approx 13.8 v.

5 years ago by RNinMunich

Wiki

Lead Acid Battery Charging

DRAFT: TO BE REVISED AND UPDATED SHORTLY!! (RN) should not be discharged and kept charged up as much as possible. Discharging these batteries will reduce their capacity. if they are kept for any length of time without a charge, they will not charge up again. To charge up these batteries use the same formula. However can cope with heavy currents and it is sometimes a good idea to charge them up with a higher current. Now and then charge them up with double the current as usual and for half the time. So for example, a 5000mA/h battery, should be charged on 1 Amp for 5 hours. Winter Storage To ensure they will be fine when next used make sure they have a top-up charge every couple of weeks. Half the length of time of a normal charge. DO NOT HAVE THE BATTERY ON A CONSTANT TRICKLE CHARGE! Large 12 v (e.g. old home security batteries) have a time constant of approx 4 hrs so need to be charged 5 x 4 hrs = 20 hrs. I leave mine on overnight which usually does the job, offload battery volts are approx 13.8 v.

5 years ago by Tall Paul