Topic: Rhyl Mersey Class Lifeboat (Read 40539 times)

gribeauval · « **on:** August 12, 2015, 10:55:45 pm »

Next build on to the slipway is a 1/12th scale model of the Rhyl Mersey Class for my North Wales client.

I already hade a grp Mersey hull in the back of my workshop so it was dug out and checked over. It looked to be ideal for the build, but after a few weeks of looking at it and checking I decided that it wasn't up to the standard, in both finish and dimensional accuracy, that I wanted so............. scratch build hull time!! The superstructure was already going to be scratch built as it is to have a full interior etc.

The file box with the Mersey drawings was opened and the lines for the hull printed at 1/12th scale along with 21 copies of the body lines and stuck onto the "work in progress" pin board in my hallway.

The pattern for the keel made, ready to transfer to the ply.

A construction board was prepared with the centre line and the 21 hull stations marked. Brackets to keep the keel in position (and straight !!) were also fixed in place.

The keel was cut out, ruffle holes drilled, set up on the board and checked that it was square to the surface in all directions as any deviation at this stage results in building a banana boat not a lifeboat!!

I have also made a jig for fitting the frames. This has the top edge at the level of the designed waterline as shown on the drawings from the underside of the keel. It is also kept vertical using the same brackets as for the keel. Each of the patterns for the stations has this designed waterline marked on them so that they can all be set at the correct hight.

This stage of the build is going to take a little time so bear with me and it will also fit with the Severn build that will be going to Cornwall Thumbup

.

Martin (Admin) · « **Reply #1 on:** August 13, 2015, 07:16:45 am »

( One of Gribeauval's previous builds! ) - http://www.modelboatmayhem.co.uk/Modellers/Mike_Pendlebury/1ndex.htm

gribeauval · « **Reply #2 on:** August 13, 2015, 07:26:31 pm »

Here are the results of three days work (started building on Monday after making the jigs over the last weekend) showing the frame jig in operation and the top location beams to keep the frames in place.

The spaces between the solid front frames will be filled with blocks of urethane foam before planking to provide reserve buoyancy just in case it's needed (Just like the real thing!!

)

Six frames fitted. only fifteen left to go !! At two or three frames a day, I like to allow the glue to go off properly ( the Gorilla glue needs about 2-3 hours to be safe) before moving to the next frame, I should be ready to plank in about a week.

gribeauval · « **Reply #3 on:** August 20, 2015, 02:58:22 pm »

The last frame has now been fitted in place and the urethane foam blocks added at the stern.

The foam infill at the bow section will be added next (after my holiday

) then planking can be started.

gribeauval · « **Reply #4 on:** August 27, 2015, 07:37:28 pm »

My short holiday over so it's back to the building board again!!

The stern blocks fitted earlier have now been sanded to final shape. The bow blocks have also been added and shaped as well and the hull is now ready to plank.

The tops of the deck beams have been checked for 'fairness' with a large flexible rule and it touches at every point giving the gracefull reflex curve of a Mersey deck from stern to bow. :Thumbup:

The location of the access holes in the deck can now be taken from the GA drawings and plotted onto the beams so that the coamings can be fitted and the sections of beam removed as needed.

Finally a view along the prop tunnels and they look OK as well.

I can now prepare the first layer of planks and start adding them over the weekend.

onora · « **Reply #5 on:** August 27, 2015, 07:57:19 pm »

Looks good, alot of work, Is this going to be a making of a mould or just a hull?

gribeauval · « **Reply #6 on:** August 27, 2015, 08:24:43 pm »

Quote from: onora on August 27, 2015, 07:57:19 pm

Looks good, alot of work, Is this going to be a making of a mould or just a hull?

Just going to be a hull as I don't like working with grp unless I am forced to do so.

Mike

onora · « **Reply #7 on:** August 28, 2015, 12:49:48 am »

Cheers Mike, thanks for replying. Not nice stuff GRP

Peter · « **Reply #8 on:** August 28, 2015, 04:09:13 am »

Hi Mike,

Your build is progressing well, looking forward to following this.

Peter

gribeauval · « **Reply #9 on:** August 29, 2015, 06:14:35 pm »

The position of the superstructure has been plotted onto the deck beams, extra deck reinforcing added and the centre sections removed to give me access to the interior of the hull.

The beam sections that were removed have not gone to waste !! They have been used to stiffen up the side decks.

Decks and coaming next on the agenda.

gribeauval · « **Reply #10 on:** September 01, 2015, 08:36:48 pm »

All the glued frame components have now fully cured so the deck was next to be fitted.

This was glued in place in five sections (two at the bow, one at the stern and the two side decks) to accomodate both the sheer and camber of the Mersey deck. The slot in the bows for the recovery strop will be opened up after planking. The final shaping will also be done after the planking is completed

When these had been fitted the main coaming was added. This was made from 1.5mm thick material as it has to fit between the two skins of the superstructure as there is to be a fully detailed interior fitted. This is the method I first used on the Tyne class lifeboat RFA Sir Galahad to great effect.

morgsy · « **Reply #11 on:** September 02, 2015, 01:57:13 pm »

She's looking great Mike, and sir Galahad is amazing, never ceases to impress me both in and out of the water

Rhys

gribeauval · « **Reply #12 on:** September 04, 2015, 09:36:33 pm »

Planking has now commenced!!

The first layer is being done with a combination of thin and wide planks, on the flatter sections of the hull, and after sanding and adding reinforcing on the inside will allow the final shape to be corrected with filler where needed.

This stern view shows the sweep of the tunnels into the rest of the hull.

The top layer of planks will be fitted with much closer joints.

gribeauval · « **Reply #13 on:** September 30, 2015, 08:39:54 pm »

Finally finished fitting the planks onto the hull framework. The inside has been given a coat of polyester resin to harden up the balsa planks and also to ensure that they are firmly fixed to each other.

When the resin had cured fully the whole of the outside was covered with a thick layer of ordinary filler and now looks like an iceberg! Over 95% of this will be sanded off in a few days, when it has fully hardened, just leaving it in any hollows and the small gaps. This sanded surface will then be coated with sanding sealer and lightweight aircraft tissue to harden the outside and make it ready for painting.

gribeauval · « **Reply #14 on:** October 03, 2015, 08:32:52 pm »

Just spent the last two days covered in white powder and looking like a snowman whilst sanding most of the filler back off the hull !!

The hull is now looking like a Mersey and not a large white blob. The bilge keels have been cut to size, shaped, bonded and faired into the hull. Also the stand for the boat has also been built.

I can now add the top layer of tissue and dope, plus more sanding, then start to add the main structural details onto the hull, I also need to cut the recovery stop channel on the bow deck.

gribeauval · « **Reply #15 on:** October 07, 2015, 07:23:38 pm »

Whilst waiting for the resin on the outside of the hull to harden off I made some of the external hull bits.

The twin rudders have been fabricated from styrene.

along with the reinforcing frame for the end of the tunnels.

The frame has been fitted onto the stern and faired in to the tunnels and the rudder tubes also glued in place.

The prop shafts have also been fitted into the hull. The discs are used to enable accurate positioning.

gribeauval · « **Reply #16 on:** October 16, 2015, 08:39:32 pm »

A major cock up has occured with the outer skinning of the hull. In places the resin matting has refused to bond to the hull properly or refused to set. This may cause problems with the final finish later down the line so after trying to solve the problem for several days I have decided to switch to Plan B!!

This means that the grp hull I have is in for a major remodelling job, sort of a face lift and nose job combined with botox!!!

Inside the hull the keel space at the bow and strern has been filled with resin to allow the outside to be reshaped with the big power sanders.

The profile of the sheer line has also been altered as new decking sections have been added.

The stern has also been 'remodelled with the sanders and the positions for the exhausts and ram boxes plotted.

The shafts and rudder blocks are now bonded in place in this hull.

New motor mount is under construction.

I have also solved the problem of making the recesses for the exhausts that are moulded into the stern During a visit to a local pound shop this morning the answer appered in the shape of plastic shot glasses!! The base of these are the correct diameter for the recesses. So a section was cut off the lower end of the glass.

Styrene discs were cut and glued to the removed section. These are where the bolts that hold the pipe in place are fitted.

34mm diameter holes were cut into the stern with a stepped cone drill.

The new recesses bonded and sealed in place, after sanding flush the exhausts themselves can be added.

Next on the agenda will be the reinforcing for the end of the tunnels and the ram boxes.

Can now relax at the Blackpool Boat Show tomorrow, talk Lifeboats with old friends and pick up more supplies for the build. Thumbup

nemesis · « **Reply #17 on:** October 20, 2015, 06:42:09 pm »

Hi Mike, I had this trouble with resin not setting and after consulting the experts I found out. If you are using waxed resin you have to shake it well to disperse the wax as it settles out at the top. If not you get wax rich liquid which looks like resin. I might be telling a gran to suck eggs, if so I am sorry. Cheers Bill Carpenter

gribeauval · « **Reply #18 on:** October 20, 2015, 08:19:40 pm »

Quote from: nemesis on October 20, 2015, 06:42:09 pm

Hi Mike, I had this trouble with resin not setting and after consulting the experts I found out. If you are using waxed resin you have to shake it well to disperse the wax as it settles out at the top. If not you get wax rich liquid which looks like resin. I might be telling a gran to suck eggs, if so I am sorry. Cheers Bill Carpenter

Thanks for the information Bill. I will leave the first hull alone for a month or two then remove any sticky patches left with solvent and redo the whole thing with epoxy finishing resin which should rescue all that work.

Meantime it's on with the grp hull.

gribeauval · « **Reply #19 on:** October 24, 2015, 04:01:14 pm »

I have finally finished the major mods to the grp hull !!

At the bow end the forefoot has been slimmed down, the ruffle holes opened up and the recovery strop groove made. This was done by inserting a styrene channel faired into the stem, it was also continued into the deck to allow the strops to pass under the bow fitting.

The side view of the hull now has the profile I wanted.

The kink in the keel has been removed by the addition of a straight section on top of the existing keel and adding filler where needed plus sanding back as required. The stern ruffle holes have been done and the bilge keels fitted onto the hull.

On the transom the new tunnel edge frame is in place and the ram recesses inserted and sealed in place. The rest of the deck has also been fixed in place.

Whilst waiting for a break in the weather to allow the spraying of the filler coats I have made the trim tabs ready to fit later.

gribeauval · « **Reply #20 on:** October 28, 2015, 10:00:44 pm »

With all the fog and rain over the last few days spraying of filler coats has not been possible so it has been on with wheelhouse construction!

First on the agenda is the rear wall as this needs to support the mast structure. Styrene was chosen as when used with solvent cement a solid stucture can be produced.

Back wall cut out, raised platform fitted and intake boxes etc made.

A second wall was cut out but this time with an extension down to the floor level within the wheelhouse as an interior is to be fitted. This interior wall was fitted onto the first wall but with spacers to allow the unit to fit over the coaming.

Finally for now the angled wall for the door fitting has been cut out and welded in place.

Starspider · « **Reply #21 on:** October 28, 2015, 10:24:58 pm »

Very nice work

gribeauval · « **Reply #22 on:** November 02, 2015, 09:20:49 pm »

The basic panels for the upper steering position have been cut, fitted and faired into the rear wall along with the access step and the stand for the throttles.

The main door has been fabricated from styrene sheet and parts from a commercial door casting.

The door is hinged and operational.

The main outer panels for the rest of the wheelhouse have been cut ready for sorting and fitting.

derekwarner · « **Reply #23 on:** November 02, 2015, 11:25:43 pm »

You appear to be achieving a near perfect constant edge radius fairing on or in all of your structure joints.......this in itself is very impressive

... Derek

gribeauval · « **Reply #24 on:** November 03, 2015, 01:45:09 pm »

Quote from: derekwarner_decoy on November 02, 2015, 11:25:43 pm

You appear to be achieving a near perfect constant edge radius fairing on or in all of your structure joints.......this in itself is very impressive ... Derek

It's great what you can do with a bit of filler and a lot of patience.

The outer side walls have been marked up for the vents etc, the window openings cut out and the inner wall skins cut and fitted.

The two walls are separated by a full length spacer that allow the coaming to fit between the lower edges of the two skins.

The two wall sandwiches are now fitted onto the back wall and the wheelhouse floor plate added.

The two vents on each side of the upper steering position have been made and fitted.

Inside the fitting out has been started with the rear wall trunking, the curved inner wall of the upper control panels and the access ladder made and fixed in place.

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Author Topic: Rhyl Mersey Class Lifeboat (Read 40539 times)