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[Spook]

So, after a year of having this big box sitting in my study, I finally made a start. About a twelvemonth ago, I started on the hull and put in the prop shafts then, after  two redundancies, a massive mid-life career change (Aged 51) and 7 months of training, I now find that have a bit more time on my hands. So, here are a few pics of the working bits and pieces that will live inside the model.

I have decided to keep it VERY simple - i.e. 2 540 motors running off a single Viper Marine 25 ESC, a 2 channel receiver (BEC) and a single 7.2v battery. I also decided not to go for the working stabilisers, as this was my first attempt at serious r/c from scratch. I may have located the rudder servo a bit too far away from the actual rudders, so will probably add an eyelet somewhere along the linkage to keep it nice and straight - although it does appear to work quite nicely without any help during dry testing. I mounted everything clear of the bottom of the hull, after reading in these forums about the tendency of the rear hatch to leak under certain conditions. (Yes, I know the battery is wonky, but it's just held in place with velcro, as are the board-mounted bits, so it can be adjusted later.)

Please don't hold your breath waiting for more pictures to follow straight away, as my spare time occurs about once every four weeks, and I have sooooooo many other things that I want to do, now that I have the time.

Cheers,
Spook

[westcoaster]

Well, now you've started I'm sure you will find more time to progress with it. Having watched Dicky Ds' build of this boat, it's clear that this kit produces a good looking model. Good luck with the build and post us more pics when you get the time.

[Peter Fitness]

Spook, you will need some sort of support for the rudder push rod, it may be OK out of the water, but water pressure may cause some flexing if it's unsupported, particularly as there are 2 rudders.

I built a Sentinel back in 2005, and it's a great model, both to build and to operate.

Peter.

[DickyD]

Hi Spook, my build is on here if it is any help.

http://www.modelboatmayhem.co.uk/forum/index.php?topic=17000.0

[Spook]

Peter - that's what I thought - I'll knock something up - maybe an old ballpoint pen tube on stilts?

DickyD - I have read through your build already. Lots of useful information there and I will certainly be referring to it as I progress.

Thanks

[Peter Fitness]

maybe an old ballpoint pen tube on stilts?

I hadn't thought of that one, but there's no reason it wouldn't work. As long as the rudder push rod doesn't flex you should be OK.

Peter.

[Spook]

I decided that a ballpoint pen tube might be a bit too 'chunky' so I have used a plastic drinking straw. The tendencies to bend/kink are very different between the straw and the servo wire, so they keep each other straight. Here's hoping! ;-)

[rem2007]

Hi Spook,

good name considering its almost Hallowee'en, I was up your way yesterday. Didn't see much aside from the inside of the UK Border Agency office in Cardiff and loads of rain. Apparently I went over the Severn Bridge, but it was raining so hard I didn't realise until I had to pay the toll.
Anyway, still abit of a novice myself, but I'd think you'll need something else to hold those twin 540s, as is you get up planing for any duration they will generate some heat.
A bigger 7.2 pack will be in mind as well, maybe 3300mah for some time at speed.

Just a thought, I hear you have ice hockey in Cardiff!

Robert 

[FullLeatherJacket]

Rob
Hooligan 
Nellie is NOT a planing boat.
FLJ

[DickyD]

I have a 7.2v  4600mAh racing pack from Component Shop in mine which is just about right and as Dave says, it doesn't plane.

[rem2007]

....oops, but still elastics will get warm, sorry

[justboatonic]

Hi Spooks. Good luck with the build, I think MSW make cracking kits.

If I may make a suggestion or two though, your motors dont seem to be secured very well with that rubber band stretched over the two of them. You could use a decent blob of silicone sealer beneath each one. This will fix the motors in place and also absorb any vibration when they are running. Also, try and get the motors in line with the shafts such that the coupling is in a straight line between the prop shaft and motor shaft.

The way you have the rudder linkage set up, you may also be introducing some differential into the throw ie you may have more left than right. I'd try and get the linkage from rudder post to servo to form as near as a 90 degree angle as possible by moving the wire to the other side of the servo arm. Check on access though.

[craftysod]

If i may make another reply to help you,
The length of wire you have got,between servo and rudder,will bend out of shape,as soon as you apply any pressure,to it.
The servo is only supported at one end,and looks like the wood has already split by oversize screws.
Constructive critism to help out,as we have all been there
Mark

[DickyD]

Could I suggest that it might be a better idea if you bought an extension lead for the servo and moved the servo nearer the rudders.

[rowdyates]

Dicky,

Why do you have the extra links from the rudder?

Rowdy

[Peter Fitness]

The links from the rudder are for working stabilisers; I did a similar thing in my Sentinel as shown in the photo.

Peter.

[FullLeatherJacket]

Just in case you're wondering whether or not to fit these, my original plank-on-frame model has fixed stabilisers and is still very stable in turns.
FLJ

[DickyD]

As Peter said they are for the working stabilisers, Rowdy.

Take no notice of FLJ he just designed and built the prototype so what does he know ? 

[FullLeatherJacket]

Take no notice of FLJ he just designed and built the prototype so what does he know ?  

[Spook]

OOPS! Guess I should check the forums more regularly - I've just fitted the decks!

But, in response - thank you all for the advice.

I thought I'd try it with the current battery as I already had it but would replace it with another if necessary.

I have added more rubber bands to the motors but was thinking of sticking them in place permanently. Sealant sounds like a great idea.

I have supported the rudder wire with a plastic drinking straw, which appears to do the trick - the straw prefers to kink, rather than bend but the wire wants to do the opposite, so they sort of cancel each other out.

I may well resite the rudder servo if it gives me problems. I can do that later as there is ample elbow room for tinkering.

And yes, the wood that I have mounted the rudder servo on has split. This is a testament to my cr@p woodworking skills and an eager impatience on my part when it came to installing the r/c gear.

Installing the decks was 'fun'. Lots of trimming and filling. It didn't help when I found that the lateral supports for the aft hatch were lower than they needed to be and the transom was a little higher. Still, with pieces of scrap and lots of patience it doesn't look TOO bad.

Oh yeah, and my foredeck is a bit too high (I must get my varifocals replaced) so more trimming on the way.

I should have some more pics soon.

[Spook]

Sorry - haven't been updating the thread - been too busy building a boat (and other issues).

However - it's just about finished. I cut a few corners and made a few mistakes though ...

1) Rails - I cannot solder for the life of me, although I had a go (and got burned frequently) so I have done a very crude cut down arrangement of the rails.
2) A lot of the little things (watertight door handles hatch hinges etc) were left out as they are only going to get knocked off with wear & tear anyway
3) Pole mast - Like I said, soldering is not my strongest suit, so a "make do and mend" strategy was applied - but I think it looks OK.
4) I totally screwed up the windows, managing to get glue on just about every pane of "glass" on the boat - my excuse is that my hands are not as steady as they used to be ;-)
5) The waterline is a little lower than it should be - haven't tried the "float test" yet, so hope I don't need much ballast.

I have ordered a 7.2V 4200 mAh battery
I haven't made any adjustments to the r/c & steering yet. I'll see how it goes and then make any adjustments as necessary. (but I did support the rudder wire with a drinking straw, which seems to work OK).

So here's a pic - not very good quality as I took it using my phone. I'll get some more using a proper camera.

[Spook]

Some slightly better pictures. If you don't look too closely, it ain't that bad for a first attempt. (I'm not counting the yacht I built as that was a very simple kit and didn't involve much work)

[Spook]

Remarkable!    I inserted the new battery, half-filled bath with (freezing cold) water and, after moving the battery around a few times, the vessel floated pretty much to the waterline. I had to offset the battery slightly diagonally to port to compensate for the weight of the davit and rib. She's very slightly low at the bow (a couple of mm), but should look fine on the water, as the bow will raise when the vessel is in motion. Hopefully we'll get onto the lake after Christmas. Can't wait!

[Spook]

Well, due to sickness (and rubbish weather) over the Christmas break, she didn't get into the water. If we get a calm dry day in the next week or so I'll be down the lake like a shot! Batteries are charged and the car engine is running. I'm on night shift until Sunday so might get a small window in the afternoons  (then 3 days off). 

[Spook]

Blimey, was it really that long ago that I finished the build?

Havent been on the forums for a while.

Well, she's been on the water a few times on Barry boating lake and runs very well. After almost losing the superstructure, when it fell off during a tight turn (and landed upside down so that it floated) I secured it with rubber bands and hooks. I'm getting overheating problems so the ESC is cutting out, not sure how to cure that but, that aside, I'm very happy with the results.