Back to the Drawing Board - almost

Mike Garside · 23 April 2002, 11:28

Ever since we got back from Cardiff after the SOC bash I've been sucking my teeth about what to do with Magellan Alpha (a 9m Ribtec that used to be called B-4). The trip - our first outside Falmouth Bay - since I bought the boat third hand from Tim Wilks at Ribtec, proved that...

1 the boat is seriously underpowered for it's length and weight. The Yamaha 165 diesel can only deliver 20 kts max.

2 It is overpropped. A test suggested by Jim Mackintosh through Alan Winnet was to try revving the engine to 3600 in neutral to see if it got there. It did easily, which proves, I guess, that the max 3,000 I can get in gear indicates overprop.

3 The range is hopeless. The tank only holds 200 litres and with the weight of the boat and the oversized prop we were burning 3 litres a mile to produce 20kts!

After listening to good advice from many who know far more'n I do about this I have decided to settle for an engine upgrade to the Yamaha 240hp - mainly cos I can use, I believe, all the same mountings, fittings, leg and ancillaries as the current engine.

I also plan to add two new underdeck tanks to increase the fuel capacity to about 500 litres. Syphoning diesel into the main tank from 50 litre cans on deck off Lands End in a Force 5 on our way home after seeing off Alan P and Co. was more than just a little messy.

Once this is done, Diana and I feel we can put in an appearance on the scene and have some hope of keeping up with the rest of you!

But first things first. I've never undertaken a task of this sort before and would appreciate any advice - other than don't do it - that you guys can offer. In particular....

1 To start. Should I just cut holes in the floor big enough into which I could drop tanks? I've got a set of builders plands and reckon I could find the right places.

2 What sort of tanks should I fit underdeck? Do I measure up and get someone to make them up in stainless? How should they be fixed down? How should fuel lines be linked up?

I guess that's plenty to be going on with for now.

As I said....any advice would be gratefully received.

Cheers

John Kennett · 24 April 2002, 10:12

I'm not sure about fitting the tanks in Magellan Alpha -- the spacious cabin means that accessible deck space might be a bit tight!

I would definitely go for custom made stainless steel tanks. Rather than try to give the fabricator detailed drawings and measurements, make cardboard dummy tanks that you can test fit, then use them as patterns.

If you can wait until Alan Priddy gets back he will probably be able to help -- he's done a few radical surgery jobs on RIBs over the years!

The changes that you've got planned will revolutionise your boat and make it into a seriously good cruising machine.

John

Mike Garside · 24 April 2002, 11:12

Thanks for that, John. The temptation of waiting to do anything until Alan id back is very strong but he'll have plenty on his plate in the aftermath - to say nothing of the fact that even he may need a proper rest this time.

I'll go with your advice for a start. Hole cutting and cardboard mock-ups. Any idea for an experienced tank maker? Or do I just look thro Yellow pages for any stainless steel fabricator down in the South West?

John Kennett · 24 April 2002, 13:53

I can recommend Hilsea Engineering in Portsmouth. They made the tanks for Phoenix and for Spirit of Cardiff, as well as A-frames and various other steelwork. They also make stainless steel fittings such as tanks, grab handles and backrests for a number of RIB manufacturers, not to mention the interesting (!) contraptions on the Camel Trophy boats.

Hilsea Engineering
1-3 St Georges Industrial Estate
Rodney Road
SOUTHSEA
PO4 8SS

023 9275 1643
Speak to Roger

John

Mike Garside · 24 April 2002, 16:54

Thanks, John, I'm on the case!
Cheers

Alan · 24 April 2002, 16:57

Part of the essential appeal of a RIB is the high cruising speeds -25-30kts than can be maintained. Essential for any distance work and much more fun!

JK is absolutely right about going for stainless tanks. I've had bad experience with glassfibre ones. Presumably the guys at RIBTEC could give you some advice about where to cut the holes in the deck? I would imagine tanks need to be resting on some glassed in bearers and then bolted down. As far the technicalities of fuel lines etc you need an engineer there mate!

Cheers,
Alan

Mike Garside · 24 April 2002, 17:27

Again, thanks for that Alan. Stainless it will be.

Actually, I did start with Ribtec but they are not really interested in getting involved. Tim Wilks says they're too busy right now and are in the middle of planning a move for the factory down to Bowman's old yard closer to Southampton.

Interestin' approach that. In my days as a marketing man I believed it usually paid to chat up people who had bought your products in the past as often they buy from you again. Still, what do I know????

Alan · 24 April 2002, 17:52

In my experience RIB builders almost without exception view each transaction individually and once having sold the boat to you are only interested in you when you place an order for a new one. The fact that they've pissed you off so much that you aren't going to buy the next one from then even if they paid you seems to escape their attention! I am surprised that Ribtec wont offer advice over the phone if nothing else.

Mind you are proper powerboat or yachtbuilders any better?

Jono Garton · 25 April 2002, 22:02

Mike

For ss fuel tanks you could contact Premier Fuels in Castle Donnington, Derbyshire - they build tanks for F1 cars, planes, boats - everything.

Sorry I have not got any contact details.

Another thing I would suugest is having a fuel pump between the two tanks ie when you have 50% fuel you can have 1/2 in the port tank and 1/2 in starboard (or 1/2 in front & 1/2 in back).

Mike Garside · 26 April 2002, 06:55

Thanks for the Premier Fuels contact, Jono. I'll check'em out and see if they're interested.

On the subject of a linking fuel pump, I can see the benefit of balancing the load and that makes sense. It looks as if my layout will be three tanks in line, fore and aft.

My current thinking is to use them independently in the order: centre, aft, fore. (The boat will need a bit of foreward ballast after I have cut out the ballast to accomodate the front tank. I believe it was stuck up at the front end cos the first owner didn't want an extra fuel tank there.)

The other reason that I was considering independent unlinked tanks is to prevent cross-contamination of the fuel. I think this was something that Alan Priddy put in my mind. I believe he uses a 'day' tank linked directly to the engine and tops it up buy pump from the other on-board reservoirs.

Does that make sense?