RNLB Mersey

[Steve Gregory 1Participant @stevegregory1]

I am starting a scale build of a Mersey Class lifeboat in 1/12th scale and would like to ask if anyone has already built one and if so, what electric motors did you use?

I have been recommended to use graupner 900 bb’s, but at present, these motors are not available anywhere, can anyone else suggest any.

er I have been warned that the MFA 850’s are “power hungry” and soon drain batterys………

[Steve Gregory 1Participant @stevegregory1]

1/12th Scale build

[RedpiperbobParticipant @redpiperbob16487]

Hi Steve I am building a 1/12 Trent I am using two MMB 900 motors from Action Electronics And Dave’s ESC too.

Bob

[ashley needhamParticipant @ashleyneedham69188]

Steve. Alternatively… The MFA 850 is a revvy 9,5000 Rpm motor on 12V and will pull about 10A with a 50mm prop. I dont know how how fast you want to go, but the the MFA 800 is “half” an 850..5A and 5000 Rpm with a 50mm prop. Both motors generate some stonking torque.

 

A pair of 800″s propels my Fantome (48″ by 12″) very adequately , as an aside.

 

Ashley

[Dave MilbournParticipant @davemilbourn48782]

Steve

If I can believe Wikipedia then a 1/12 scale Mersey is about 38″ long c/w the big 1/12 scale Trents, Tamars and Severns which are all over four feet. It’s also not a fully planing hull so needs less power than otherwise.

The props would be something like 35-40mm dia 4 blade – yes? In that case we can offer either the 755 or 555 motors, both of which would run these props happily on 12v, with the 755 motors having more “oomph” if you need to stab the throttle to get you out of a fix. Graupner/ACTion/MMB 900 motors are very big, powerful and heavy things and would be too much for a relatively small model like yours.

Dave M

[Steve Gregory 1Participant @stevegregory1]

Right, Mersey hull has now arrived from Models by Design. Supplied with 55mm “handed” props [4 blade].

I decided fist job was to give it a wash over, then apply a bit of “knifing putty” to all the slight imperffectiosn in the outer gel coat before any sanding work starts, so it can all be knocked back together, making life a little easier.

[Steve Gregory 1Participant @stevegregory1]

hull has now been sanded again after a few more filler points sorted and has first coat of grey primer, this has now highlioghted a few more areas to be filled, so will do these before further flatting and priming.

[Steve Gregory 1Participant @stevegregory1]

I have now managed to finsih filling and sanding the hull off and applied its first coat of white paint to the lower half. Once fully dried this will be given a final flat with some 800 wet paper and painted again. a third and final coat will go one after this has dried, once flatted with 1200 paper.

[Steve Gregory 1Participant @stevegregory1]

the lower hull has had a further 2 coats of white paint. this has dried sufficiently for it to take masking tape [48 hrs], so have masked the white off to apply the deep blue upper band. this had had 3 deep coats of paint to give added deepness to the colour and glossy “sheen”. I am yet to finish off the edge between the colours as too soft to clean yet.

[ashley needhamParticipant @ashleyneedham69188]

Steve… and the motor conundrum???? need a post from someone who has built one of these.. must be some lurker out there !!

 

Ashley

[Steve Gregory 1Participant @stevegregory1]

I have the motors sorted thanks very much.

i have battled long and hard for some info on this and had very little “sensible reply”, so keeping “stum” on the outcome. Other builders of this particular boat are extremely reluctant to give any info away. dont ask me why, i dont know, because they wont say or suggest anything.

 

So I’ll continue the build alone.

[Steve Gregory 1Participant @stevegregory1]

Started on fitting the internal wooden support pieces today. I use stabilit express glue to attach the wooden pieces to fibre glass, once in, it dont move again. Ive had to put a fair few saw cuts in to the wood, simply to get it to bend to the correct shape.

 

once the glue has fully dried, the saw cuts will be brushed and filled with a nice runny mix of cascamite to put the strength back in to the wooden pieces.

[ashley needhamParticipant @ashleyneedham69188]

Steve, a bit of a disappointment I`ll say. The problem with this lark is nobody will agree on a combination of motor/prop/battery, even despite some advice from the last mb special..

 

Never mind, good luck with the rest of it!

 

Ashley

[Steve Gregory 1Participant @stevegregory1]

I have now started construction of the rear section of the main cabin. Careful measurement of the plans and conversion to 1/12th scale dimensions needed at all times to ensure accuracy. Especially as there are quite a few angled pieces involved.

I am using styrene sheet , admittidly I am well versed with its use in previous scratch builds, including my “Egrete Pusher tug” and RMAS Moorhen. its a light very easy to use item and can give sufficient strength to support where necessary.

[Steve Gregory 1Participant @stevegregory1]

Have started work on the stern flying bridge section, so at least this will strengthen the open rear end of the cabin up, before any internal work is commenced.

All items are made from styrene sheet, for simplicity of construction and also weight.

[Steve Gregory 1Participant @stevegregory1]

Ive now started construction of the rear cabin door, being as the layout and build of the open wheelhouse area is going ok. I decided to make the door in a similar fashion to the speedline window kit I have in stock for it, so its a “sandwich” construction.

The main door fram, has a clear perspex window panel, topped off with a further “window surround” frame.

Now how to recreate the retaining bolts?

I was simply going to carefully “slice” a load of pieces off a length of olid plastic rod, butcan’t really guarantee each one is going to be same thickness at such a small size, so Im going to experiment with drilling the completed door, making a series of holes all around the window frame, then cutting lengths of plastic rod to pass right through the door assembly, thus creating a bolt/nut effect on both sides in one easy go.

 

more pics once ive managed to do such, see what you think !

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