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[warspite]

 :) Well here we are, these are the first pictures for this build, hopefully they will come out alright, as they are all composites of 4 pictures each, put together to make the upoad for so many pictures a lot quicker.

Most have already been shown in other threads as the running gear for this build is going to be problematic at best. I have decided to go with the better of two options, a light running gear i.e. one prop, one motor and micro equipment to drive, thanks to FullLeatherJacket, Malcolmfrary and bunkerbarge for all their help.

The first set of images show the initial equipment to be used, this has now since changed somewhat, but it gives an indication of what was originally going to fill the boat, I have previously stated that it does not take much to weigh down this hull, as it is just too small to displace sufficient water for the depth of plastic used to make it. The only option is to reduce what is fitted, and lose as much excess weight as possible, if i can get it running through the water to simulate cruising all well and good, getting up on the plane and it's a bonus, when funds become available, may even look at fitting one of the brushless motors at a later stage, that means in the final assembly of the deck, I will have to concider sealing her with a mastic sealant, and light areas of normal plastic kit glue, this will hold the deck in place and seal her, but allow some lea way in breaking in at a later date.

At some point, what i do will need to be revised, I am no expert and will do things that will confound most, any comments will be greatly appreciated.

[warspite]

 :) As I do not know how to insert text yet between pictures i will place it here, In the last photo i was concidering using the original crew to help, all I got was "were combatants, we don't do building" and they stayed fixed to the sprues, lazy bunch of @@**@!, any way, another team of three turned up with some kit (i don't think they will need the flying carpet, it does not have an extending section to get to the rigging, they will have to use a normal ladder and struggle like everyone else), the wife had the washing machine on, so they had to shout to hear each other. Seemed keen to read the history, wern't to happy about there being german instructions below - wonder why ::)
(borrowed the idea from martin and his crew - don't worry martin, they will only appear on the fitting out phase if i feel depressed and need to cheer up).

The photo of the actual motor is next to a matchi servo motor sold by action, slightly smaller than the proposed 'MAPLINS' cheap motor, but as powerfull as a standard servo motor but better quality, this motor on the other hand is a little faster and hopefully has better torque, I have an atom for steering and an ACTion P68 for speed control, (very nice FLJ), the prop tube is from the test and has been extended for the build, also extra stiffening added, it's now glued in place and seems solid enough, have put some slick 50 into it and fitted the prop, and yes, it is a bit harder to rotate, hopefully the motor will be sufficient, but until the running test I will carry on with the build.

To reduce the weight I have gone to the lengths of removing plastic in the deck where it is not needed, i.e. under places where a cover will be fitted or superstructure, no point in having a duplication of the plastic when it is being capped, as long as it is well sealed there will be a few grammes removed.

To charge the fitted batteries in the finished boat, I am planning to fit the charger socket as shown, hiding it under the rear cover. Batteries will be a light load, probably the overlander 4.8 x 700, split down to distribute the weight, luckily the charger socket also doubles as an isolator switch when plugged in, separating the receiver from the incoming current, thereby saving on a seperate switch.

I will post when other photos become available
Warspite

[warspite]

Well, after a little break from the vosper, allowing the araldite for the prop tube to 'cure', i have now gone back onto it, having cleared some space in the loft and put a work bench up there - i am now consigned to the naughty room by swmbo 'yipee'.

I also completed a black ops boat project just to pass the time and try the old modelling skills, though from what i have just done for the vosper, i think i need to practice a bit more.

Well it is only a bit of fun, the hole was cut for the fitting of the ATOM servo and a long arm butchered to act as the fixing point for the rudder, now i had a brain wave (or maybe an anurism depending upon your point of view), but i thought it might have better steering control with a double rudder (the kit has 3 with 3 props - so as i am already modifying the original concept - what the hell).

I know the rudder is off centre slightly and the shape has yet to be cleaned up, but the movement seems to suggest that it will give a reasonable steering circle. 

[warspite]

  well the latest update for a long time, I am trying to work out how to wire this effectively, so some test of two motors will have to be done.

1. The small cheap motor from maplin, I will have to wire this in with the intention of running the rig with a load similar to the completed kit.
2. The motor that is being planned as the actual motor, again the test run will decide which will eventually be used.

Weights :-

WoW -  is it that much - steve check this out.

Hull             - complete with fitted atom servo, brass rudder(s), prop shaft, prop tube and prop - 57g (i'll have to reduce this somehow)
Motor         - planned motor (the cheap maplins one may be lighter)                                       - 30g
Reciever     - Hitec Feather                                                                                                - 10g the cover is about 0.5g so great saving there
ESC           - AcTions P68                                                                                                  - 8g without the box
Deck          - With as much of the plastic that is not being seen or duplicated removed              - 31g (included the power plug)
Plastic parts - Now assuming that each of the sprues has 50% of usable plastic - No 1                - 12g (50% of actual weight)
                                                                                                            - No 2                 - 11g
                                                                                                            - No 3                 - 13g
                                                                                                            - No 4                 - 12g
Total                                                                                                                - 184g of which about 80g is above the hull

In all the weight does not include any further amounts of epoxy or cement glue paint solder or wiring, she sits with all this weight quite low in the water, the positioning of most of the superstructure is mid to rear so will push the stern down and the bow up - hopefully, will have to see

[warspite]

  well have tried the two motors in a test to see what the power usage is, not being sure what i am seeing i hope someone will be able to tell.

First of all the ESC (P68) was connected to the receiver, the gray lead attached to the Red side of the motor using a crocadile clip attached to a multimeter, the white fixed in a similar way to the neg of the motor.

The planned motor rotated using the ESC forward and reverse (this test boat has a prop which rotates anti clockwise when looking from the prop to the motor) the reading on the multimeter shows what i believe was brown 20 (or could have been 4 or 100 depending on what you think) the P68 did not thermo cut out after a minute of running although did seem warmer after.

Whereas the maplin motor only got to brown 17 (85 or 3.4)

The setting of the dail was 10 DCV, so on 4.8V does anyone know what is the current draw is and how long would you expect it to run for - it is in free running, so when connected to the prop and under load conditions in water, the readings should be higher and give a better idea of how long it would run for.

Picture 1 - cheap motor
Picture 2 - display of multimeter DCV brown under wide silver mirror effect
Picture 3 - dial of multimeter

any comments?

[warspite]

  Right,

First tests,
motor no 1 - planned motor ( planned refers to what appears to be the most suitable motor based on weight, rotational speed and size) originally in free rotation was 4 / 20 / 100, weighing in at 30g, installed using a heat shrink flexible connection, not particularly smooth running, a more solid connection would have probably given better results - 3 / 15 / 75 (remember i do not know which of the markings relate to which value when the dial is at 10 DCV), as the P68 is rated at 1 amp i am assuming it is in the region of 0.15 amps.

motor no 2 - cheap maplins motor, originally in free rotation 3.4 / 17 / 84, weighing in at 18g, installed (see the photo above) with a aircraft linkage connector which pushed onto the prop shaft without any additional items etc, shrink tubing, due to the test system it was on originally, used an epoxy glue whose remnants provided sufficient interference. As for running, this appeared to be better that the other by a significant amount, the values were 1.2 / 6 / 25.

I placed the multimeter contacts onto each of the terminals on the motor - is this correct and got the figures indicated, or should i have placed it in series with say the positive?

I am charging the battery overnight to resume the tests again in reverse i.e. cheap motor first and planned motor after, and will post the results tomorrow.

As for water movement, both moved water quite quickly, more so the planned motor, being heavier it appears that it may get up to the plane eventually, but the power usage would probably give out before doing so - or the ESC overheat, whichever came first. As for the cheap motor, this moved the water at speed, but i was not left with the impression it would get up to the plane, although at just over half the weight and a better fit, my concern it would 'BURN' out before to long. When the second set of tests are run, i will need to run the boat in the bath to see how fast it could go, i would have to weight it accordingly to achieve a reasonable result, i am not looking at making it jump out of the bath, but achieve a decent scale speed, i did not with the planned motor expect to see the bow rise up the side of the sink as much as it did, whether this was due to the weight distribution (it actually sat lower in the water over the whole length, whereas in the cheap motor test, the hull was further out of the water) or more likely due to the apparently 3 times more power - this is the reason i want to run the tests in reverse with a fully charged battery.

Hopefully the planned motor test will get the boat up to something resembling a plane in the short run of the bath, if it looks like it would, a quick test on a larger body of water will be called for with copeous amounts of cling film to protect the insides.

[dougal99]

To read Volts you place each multimeter lead on the terminals of the motor having set the meter to read volts. The scale that has a full rreading of 10 will be the one you need if the dial is set to 10 DCV.

To read amps the meter should be in series with the motor (that is one meter lead connected to the motor and the other connected to the battery/speed controller) and the meter set up to read amps.

HTH

Doug

[warspite]

Thanks Dougal99, it appears i was reading the volts then, through the speed controller the voltage will have been 4V for the planned motor and 3.4 for the cheap maplins one. I do not know where to set the dial for the amps and which scale to use to determine the amps drawn, so i will need to check with the electrician at work -  so a ribbing from him then.

So here is the results of the second test - will need more tests  

What happened, attached everything and ran the bath, the hull was placed in and the main 4.8v-600mah was adjusted to suit a more favourable trim, now the first of these tests was with the cheap maplins motor, 18g and connected via a aircraft linkage with residue epoxy giving an interference fit.

Full throttle and if this had been a launch going from a battleship to the dockside then it would have been fine, several runs and it never improved.

Replaced with the next motor, weight at 30g and connected with again a peice of aircraft linkage tube but as this did not have any epoxy inside a short length of shrink tube on the prop shaft and a longer larger diameter piece of shrink tube shrunk on to both the linkage and the earlier tube, several dry free running tests showed this worked reasonably well.

Placed into water and adjusted the weights to suit the deeper draught generated by the heavier motor.

Full throttle, now it ran faster than the previous test run but due to the weight it did not appear to get up to any significant speed, akin to standard cruising for this type of boat, if i had to guess it would have been equivelent to about 25-30mph, the bow lifted slightly but as the bath is too short, getting up to speed was too hard, with crashing into either end a problem. being open top did have its problems with water getting in, so i will have to fit some tempory hull extentions to lift the sides allowing for the top to be open. Getting the motor inline is harder than expected, even with the coupling the rear end has a noticible wobble, this in turn translated into vibration and would probably explain why some of the power is lost.

I do understand that the problem of increasing the voltage to 6V may have a small effect, but the weight increase would probably negate the majority of the speed increase.

Although i charged the Rx battery i forgot to charge the Tx - hence the signal went straight from 80 to 20 in about a minute, luckily i had completed most of the tests and was trying to see why the motor was stuttering and running at full wack - the loss of Tx power probably explains that, it's a futaba skysport 6 complete with a 9.6v - 600mah niCD battery, think i will have to change that to a niMH.

So if steve does not mind, i will copy a few of the changes he's made to his, i have started the build of the superstructure with a start weight target of 80g (based upon 50% of the plastic in the parts to be fitted, although i will be following the kits instructions. I have not changed the pipes etc and done a bit of pre painting before assembling the parts, though under normal lighting the places i have missed show up quite noticably, will have to try harder.

The four pictures are the main parts of the superstructure, the right side and the steering console, to reduce weight the console part sits on the deck part, this means there is a double piece of plastic, this was removed, i painted the back black as there is no disernable view inside, I am going to change this to white after some thought, the two pins are the rear of the handle and are being removed to save some weight  , for the handle i will have to try and simulate wear by using silver paint (or should it be brass).

So I apoligise if some of the painting is rubbish - old eyes don't you know.

[warspite]

 

Well, tried a weight reduction excercise, removing some of the brass that forms the prop tube, the following were the results

Start weight 56g (lost a gramme since last weighed the hull - must be all that climbing up and down the ladder to the loft - the naughty boy room) more likely the scales are rounding down so it must have been border line for 57g.

stripped out the prop and the rudder weight now 48g, back to the loft and cut out the piece of tubing, reweighed the hull - 47g seemed to be a pointless excercise, but every gramme counts, i also cut away a bit more of the rudder in the horizontal area, this does not effect the steering capability.

when i have put it back together, i will have to test the system again, hopefully it will run better if not it looks like racing prop time to see if that is any better.

Oh there is none for this size. Oh well

[warspite]

 
Well here is the bridge section, i have as yet to fit the two crewmen, i hope steve approves of the handrail, although it is not too clear, there is some silver paint to represent the wear, there is no windows fitted or the lift belts are not painted either.

I assume that the item running under the front windows is a hand rail and also that on the right hand side of the bridge, if so i need to remove those and replace with the same on the inside.

I am also perplexed why there are two holes in the left side of the bridge about the area the mast fits on the inside, unless these are for the flags etc, it's not so clear on the instructions.

I also have assembled the gun and other than fitting the clear sight, it is ready to fit to the bandstand - which is fitted to the hull. I will post a picture when i update next.

When i find my tube of grease i will be able to re-install the prop shaft and rudder and connect the motor again, hopefully this next water test will be more fruitfull than the last, i will have to calculate the speed the vessel travels at, any sugestions as to what a reasonable 'cruising' speed is (MPH - 30 40 ?).

[Niall]

Cruising speed was around 10 - 15 knots.

Most MBT attacks were made at night. They crept towards their target at 5-6 knots, fired their torpedoes and turned away from the target before running up to full speed as they retired.

[warspite]

  so what is that in Miles per hour? 

[Niall]

Multiply speed in knots by 1.158125 for mph and by 1.853 for kmph

[warspite]

  strange 34mph, you learn something new everyday, or 26 knots for 30mph,

If i can remember the blurb for the kit, they apparently could achieve between 34-40 knots, from the figures i have just calculated this equates to 8.33"/s to 9.8"/s, in a 66" long bath this should equate to 8 sec or 6.75 sec, quite slow really, apart from start and stop run i think it already gets near to this speed.

i dont know if the calculations are correct, 1/72nd of the number of inches travelled in one second comes out as above, at that speed it wont get on to the plane.

[warspite]

Well, the bridge has recieved the replacement rails on the front and right side (excuse the hole in the front - I have to fill this in later on).

The battery has been glued in place and is still setting as I type, the wiring is connected and the switch installed, all I have to do now is solder the ESC to the motor and do a final check with charging the battery insitu - fingers crossed, if all goes well the bath test will be next week.

During a preliminary check the speed of the motor was suspect from earlier tests and it appears that the motor runs faster when the TX selects reverse rather than forward, so after changing over the servo reverse switch, it should be good enough to get a cruising speed on a full charge, I then might be able to fix down the deck and finish her off.

I apologise for the quality of the paint finish, but I take the view that the boats been hand painted by the crew.  (excuses excuses  )

[steve pickstock]

Looking good Warspite, only just seen this today as I was away over the weekend and busy yesterday.

[warspite]

 

Well another update, Wired up the ESC to the motor and checked the rotation several time ( this is important to note), ran the bath and placed the boat in after another check, I have to climb down some ladders from the loft, sorry workshop.

Anyway placed it in the bath and tried back and forth no problem, lined it back up and ran it to full throttle - it went at a reasonable speed thought i'll see if it will do better on the way back - remember 6' 6" bath, two turns of the prop and           nothing, eh whats up, backwards nothing.

So i rembered all the checking i had done earlier, so oh well will see if it charges ok, so down stairs, plugged it in to charge up - no problem, proceeded to watch enigma on BBC3, which incidently showed a whale back RTTL coming directly at the main character near the end, strange, it didn't turn to the side enough to see it properly.

After the film unplugged the boat and went back to the bath (after checking the prop turned first), well what a big grin i had, full throttle and it moved farther quickly down to the other end the wash was reminisant of what i expected the bow on the other hand didn't rise up, but the wake at the front would definetly move up the sides.

The three pictures show the boat with a grin similar to mine, i held the deck on with rubber bands so a little water has got in, but wont in future, the second shows after the oerliklon position, the black plug is the battery switch - pull it out and the battery goes live, should have thought this out a bit better.

the third shows the wiring mess, it is straight forward but just looks a mess the battery is behing the feather Rx.

Conclusion - when the feather and ESC are positioned about the battery and the rest of the deck is finished most of the weight will be over the centre to rear, possibly raising the bow enough that when shes at full throttle she could lift the bow enough out of the water to reduce the drag, as a prototype one other mod will take place but we will see when that comes up.

I still believe i should have sought some way of extending the shaft of a servo motor and had two instead of a rudder, will see when steve does his.

Current weight is 168g - ouch, i think i had a limit of 186, will have to see what wire i can lose.

[warspite]

Well, fitted the deck last night, and after reducing some of the wiring length, so I will have to seal the obvious gaps and then try to fit the bridge, another sealing problem.

So the fitting out can start this weekend if the water test works out, from the following is a speed theory
40 miles @ 1760yds/mile = 70400 yds x 36"/yd = 2534400"
now divide this by 60 minutes x 60 seconds = 3600 seconds = 704"/s at full scale
now divide this by 72 for 1/72nd scale = 9.77"/s

therefore a 10 foot run should take 12.28 seconds

comments please as to wether the math is correct - as it seems very slow.

[dougal99]

Warspite

Your maths is correct but the method is wrong. To get scale speed you divide by the square root of the scale in your case 8.49. Giving 83 inches a second or 10 feet in a little under one and a half seconds.

HTH

Doug

[warspite]

WOW , never would have thought that, so i will have to figure out how fast this is on a 10 foot run when on the water - thanks will post the figures.

[dougal99]

Warspite,

Best to try and time it over a known length, considerably longer than 10 feet. 

Doug

[warspite]

Knowing the way things have been going lately, it will only have enough power to get out there and run for 10 feet before needing to get back before the battery runs out.

Later i am going to weigh it, to see what ballast i need for 10% above the 184g that I estimated it was going to be in the first place.

[warspite]

Well, the latest weight is 163g a 5g loss once the wiring shortened etc. so at the moment it is looking like 40g for the remainder of the parts - yeh right, and that has to include the paint - deep joy 

[warspite]

Well, struggling to keep my eyes open after a hot day yesterday, spent sunburning (i know what i mean) and fitting out the Vosper, I thought hang it, it's going to weight what ever it is so finish of the top and weight it then (at which time i will post some photo's in the completed phase), painted the deck etc, then realised i had not done the hull - doh!

So when this is complete i can check the weight, hopefully there will be no more than expected, bath test for water levels and then wet the hull properly.

[warspite]

well was ill yesterday - from the sunburning 

I mentioned earlier an RTTL - GRS kindly placed a link
http://au.yachtworld.com/core/listing/boatFullDetails.jsp?boat_id=1324392&ybw=&units=Feet&currency=USD&access=Public
that refered to the boat in the film Enigma - just thought i would mention it - painting the bottom of the hull tonight if all goes well