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[andyn]

That would be doing something according to health and safety rules, which I don't do

Plus, common sense would dictate that I'm not going to stick my hair into a milling machine.....

The 'fine adjustment tool' is for getting the little man to talk, I suspect he's a spy.....

Andy

[Bill D203]

What no hair-net when using a pedestal drill tut, tut.
as for the fine adjustment tool well 

Blimey he don't need a hair net that is as short as i have ever seen his hair. There must have been some spare Gas & Air in Newport if Andy has had it cut.

[nhp651]

he looks almost human   

[Bill D203]

he looks almost human   

Hi Neil
I think it's LOVE
Ah

[nhp651]

 

 

[MikeA]

dodgy having long hair. i know, ive got my rapped round my propshafts 3 times now tryin to listen to wear vibrations are coming from. you would think youd learn 

[andyn]

  I would thought you would have too

[RaaArtyGunner]

WARNING WARNING


Remember David beat Goliath
 

[Welsh Wizard]

Think We need to drag Andy to a hairdressers hold him down and give him a No3


GET A HAIRCUT LAD


Dave

[MikeA]

dont andy you must rebel!!

[andyn]

Had one 3 weeks ago

[RaaArtyGunner]

Had one 3 weeks ago

That is toooooooo frequent and can lead to Baldness.

Here in OZ we keep good heads of hair so the harsh sun does not fry our brains  

[andyn]

The one I had before that was about 6 months ago so I think I'll be ok

Sorry for hijacking your thread Neil mate

[RaaArtyGunner]

 Yes please Neil, back to Lifeboats far more interesting and informative.

[nhp651]

narh.this is far more enjoyable..... 

[Marks Model Bits]

narh.this is far more enjoyable..... 

I would rather take the mick out of Andy as well.......... Much more fun.

[RaaArtyGunner]

narh.this is far more enjoyable..... 

Ah well, as Martin has named the forum "Mayhem",  who are we to contradict him.

[nhp651]

Oh al right then, if only for Andy's sanity and well being, here goes for another bit of brain bashing.

the first quarter has now cured and the flange around the protective belting has been removed (but not the flange running the length of the keel).

Now the grp matting and resin is laid up to the upper part of the belting and alloud to cure.With this small area I tend to use shortish strips of matting around 6 - 12 inches in length and around 3" width to build up the layers, one length of the boat at a time so that a good even level of layers is achieved.

this is then allowed to cure again for 24 - 48 hours.


Once the second quarter has cured, the whole process begind again with the other side of the boat, by firstly removing the flange from the full length of the keel. The exposed grp flange must again be fully polished up and release agent added before any gell coat and resin/matting is applied, and the flange for the belting is again added to make the third split in the mould.

It is a long and methodical process to produce the mould, but if time is taken to lay the matting up slowly, carefully and with passion, you can avoid air bubbles in the mould and should end up with a "tool" that will give you a good number of mouldings from the same mould before it has to be replaced.

below is a number of shots of the finished mould in four parts and trimmed up.



However at this point the mould will still be "green" and needs to be stored correctly with the plug still in place for 48 -72 hours to allow it to cure well, or any subsequent moulding taken from the mould may come out twisted, warped or even hollow bilged...............i.e, you lay the boat on it's keel and a hollow can be seen where the keel doesn't run flat.........although this can also be caused by taking the moulding from the mould in a "green" and uncured state......so!!!, take your time and have patience.

[nhp651]

One of the worst things about GRP are the very nasty splinters that you can pick up in your hands if the mould isn't cleaned up properly...they hurt, they get infectec quickly and they are a real nuisance, so before anything else is done, the whole mould must be trimmed up......I tend to use a power file to trim down toa smooth edge once I have trimmed the edges of the flanges with a jig saw using a diamond tipped blade.

The Flanges then need to be marked for drilling, and drilled with a 6mm hole to take 6mm roofing bolts 30mm in length. Spaced at intervals of around 4" apart, and about half way between the edge of the mould flange and the inner plug the holes are drilled and cleaned up.

Finally the mould is ready for splitting. I start with the Protective belting flanges first, and, using either wooden or nylon V shaped wedges ( NEVER EVER USE CHISELS, SCREWDRIVERS OR ANY STEEL WEDGES)you can generally, with a few taps from a wooden mallet, find a starting point to drive in your first wedge.Just use a little brute force and some physics to drive in wedges along the length of the flange, and as you get towards the middle of the flange, you should hear a lovely satisfying "crack" as the release agent does it's job and the mould parts company from the plug, and you let out a sigh of relief that all the preparation that you have done to the plug has worked it's charm. It really is a great feeling, as the unknown becomes the reality and you find that you have a great mould. Just repeating the process with the second belting flange, progress is now made to split the main parts of the hull. All goes well, and an inspection of the new mould shows that a good moulding can now be taken from the mould.....approximate time to lay up a four piece mould including preparation of the flanges and lay up time .........about 40 hours.

[irishcarguy]

Andy, which hair did you cut & could we have a picture please. Mick B.

[nhp651]

Now that the mould has been split and the plug removed the former can now be cleaned up and washed down of all the release agent.
they now need to be looked at and any problems sorted. this can be anything fromsmall indentations or pinnacled left by an uneven plug to full blown repair of air bubbled in inaccesible corners where they formed on lay up. you can usually hear them rather than see them and if you go around the mould with a pencil, tapping the mould you'll get a hollow thud if there is an air bubble behind the gell coat. to remedy this, a sharp craft knife under the gellcoat will pick the surface coating away to leave the matting underneath.
It's a simple job to mix a small amount of resin with a similar amount of gellcoat and pour into the hole left. Once it has set, simply wet and dry down to the level of the mould, but don't forget the hardener. Don't be tempted to fill the hole with polyester car body filler...it won't "gell" with it's surrounding grp and will probably pop out of the hole the first time you try taking a moulding from the mould.

I usually spend a couple of hours wet and drying the moulds down with 400 and then 800 grade wet and dry, used wet, with a little fairy liquid in the warm water to stop clogging.

Once the moulds have been cleaned off, it's ready to start again...with 5 - 6 coats of wax, and then a release agent.

Finally, it's a case of bolting the 4 pieces of the mould together and then onto the making of the mouldings for the cabin and the hull, and now it is made in one piece.
I won't go into the process of making a moulding other than to say, it's exactly as making the mould...gelcoat first into the mould, and then covered once gone off with layers of matting cut to shapes easily to fit the spaces and shapes of the hull.
|The only thing to watch with the making of the moulding inside the mould is that if you get the matting too wet towards the top of the bulwarks they will fall in on themselves. here it is best to do one side of the mould at a time with the mould laid down so that the one side you are working on is at the bottom and laying horizontal. The bulwarks of such a mould as the lifeboat with the large indentation as the protective belting can weigh heavy when full of resin, and as such far easier to do one side at a time.

And finally after all that work, out pops a nice set of mouldings.
However in the next post, I'll show you what can go wrong if you forget something.....even big heads like me, make a balls up of it now and then.
neil

[nhp651]

The following two shots are what can happen if you forget to put the catylist hardener into the first mix of resin which goes straight onto the gelcoat...instead of hardening the mix just carried on burning and eating into the gellcoat, and if not removed quickly would have also eaten into the mould and ruined that too.

This happened on the first moulding of the Clyde lifeboat I made last year, when at the criticle moment of pouring the resin, I got a telephone call inside the house.
When I had finally finished talking 5 minutes later,( not criticle in the tme lapse of the resin............but very criticle to my memory lapse........I forgot to put the catylist in the resin mix, and laid up a full coating of resin and matting without hardener......and this it what happens.

Luckily it wasn't during the laying up stage of the actual mould.

Of course the moulding was useless, but I had to continue laying it up with subsequent layer of matting and resin laced with hardener so that I could get  it out of the mould...........and quickly

Even then it was  a very messy job clearing the unhardened resin from the mould........very messy indeed. So, take heed of my notice pinned to the shelf over my laying up area!!

[nhp651]

Any way, that is the EASY BIT out of the way....

The thinking cap goes on now,  and all the development work comes to the fore...solving the problems, that hopefully won't be tranfered on to the customer to sort out, and give them a model that should, if instructions are followed, be plain sailing.

neil.

[carlmt]

Absolutely FASCINATING ---- and terrifying ---- in equal measure 

Thank you Niel --- this just makes me more determined than ever to get it right 
Carl

[nhp651]

Well, Carl, if you think that was fascinating.........and terrifying, then this will surely test the metal.

It is now the planning stage of the build.
It's ok building one for yourself, because any mistake that you make can be covered up in the build of your own boat, but if you make a mistake when planning this, then the mistake will be manifested into as many models as are sold in kit form, and each mistake will maifest in complaints to the manufacturer, complaints onto forums such as Mayhem......(we've all seen them, and at times I have been guilty myself of pointing mistakes out to manufacturers)......and as such have tried my best to overcome ANY and ALL mistakes before they got into production.

This is not now a case of building a model and just describing how you did it and overcame problems.....the idea is to overcome those problems for the customer, so here goes.

Sketches and hours and hours of just looking at a model hull and cabins takes place whilst I formulate my ideas as to how the cabins will be supported on a deck and how the deck itself will be supported, in order to get easy access to internals, and even things such as replacing a servo should one go wrong and stop functioning so that all aspects are covered.

How to you make a solid deck to support and yet give space for the well decks that occur on most lifeboats of this kind.

Each set of cabins for each lifeboat I am building is a completely different shape to one another so each set of deck supports will be different, in shape and position but ALL will be constructed in the same way.

You can see below in order how different the cabind are and therefore how differently the deck beam layout will be...no two class of lifeboats will be the same.
1) H F Bailey,
2) Field Marshal and Mrs Smuts
3) Mary Stanford.

NOTE WELL:.......the bases that the cabins are sat upon are not made until the last process, and are only being shown here to high light the different shapes of the layouts.



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