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[Canterbury Coxswain]

Yes, Lance and Ned are right Derek. They are sacrificial anodes that 'dissolve' with the creation of static electricity and waterflow when there are different types of metals in the build. You will notice that there are aluminium alloys and stainless steel used in both the various water-jet components and also the relevant plates and their bolts. Hence the anodes gradually corrode as they have the least resistance, thus leaving the main fabricated items alone. The bolt on anodes are then replaced every six to nine months, I am told, when the boat is left immersed, but less frequently when the boat is removed from the water for periods - as with most of the Shannon fleet, but not all. Derek, I am sure you knew all of this, but I have now included it for others joining in the 'read' of this build. I have also been told there are more than forty sacrificial anodes in total on both the water-jets and their operating components [I will hope to get this clarified, but have added a picture showing a few more on the Starboard side].
Derek, on another small point that would be helpful with my presentation here, how do you add that 'red circle'? Which programme provides it? If I have it, maybe I will then use it, but you might have a more sophisticated software package.
John [Mk1] - I have just had another look at your marvellous scratch built 1/12th Shannon. Now you have mentioned my water-jet configuration - I have commented on my approach at the introduction of those photos, as I am using the Kehrer ones. Didn't you too? If so how did you get your water-jet nozzles in an eccentric position?

Hopefully I will be home later this evening, from my sojourn in Buckinghamshire, and back in the workshop tomorrow.
Kim

[mk1]

Hi Kim this is a photo of how I done my jet back plate as I do not have a milling machine I just used a blank piece of brass. I am looking to try and fix this on the next one. You can see how I altered the top of the nozzle so I could use rods rather than cables to turn it. I will say there are a lot of problems in trying to get the proper shaped hood / nozzles to work in reverse after building about 4 different size ones I can now get it to go backwards quite well. More on this subject later.


John

[mk1]

Hi should have sent 2 photos.

John

[derekwarner]

Morning Kim.....you have a PM on the simple creation of RED circles from Windows.....

Many years ago, we studied the electrochemical series of metals & the galvanic consequences  of such potential between different metals

I am surprised to see so many small anodic round blocks attached to the 'lowerable cover hood and the nozzle' for the jet drive, I would have assumed these to be a castings from an exotic material, however considering the operating conditions it would not be from the Grade 300 stainless series and they would certainly be hardened and heat treated

This is an interesting build & thankfully you will not need  functional real, but scale galvanic protection

Derek

[craggle]

Hi Kim

Shannon build looking great and good to watch the progress even if I don't comment quite so often these days, I'm still watching.

My Severn build is kind of on hold at the minute but looking into moving house soon and getting a place with a double garage, room for the Cobra and a boat building workshop is essential so I hope to be able to continue my build later in the year without the worry of sanding dust and glues in the living room.

Keep up the updates and keep in touch if you have any events planned in my area. 

Craig.

[Canterbury Coxswain]

Good afternoon each.........
John - thanks for adding the photos. I notice you have pivoted your water-jets with an axis at 90 degrees to the horizontal, whereas I am going trying to copy the actual boat and have them pivoted at 90 degrees to the underside of the hull at the transom - as per the plans in the photo above. I will post a photo, unfortunately I have not 'mastered' the technique given to me by Derek overnight, but I hope to crack that once the Southern Hemisphere fraternity have awoken in a different day!
Derek [down-under] - Thanks for the information requested, I have sent over an hour trying all sorts of permutations and it just will not work or give me what you say. I am on Windows 8.1. Could you give me the steps as offered - a PM is on its way - thanks.
Craig - good to hear from you. I heard you are very busy with work at the moment and now a house move too! I have not been able to book an outing on the Severn at Newhaven yet, but have not forgotten the two of you. Are there any dates to avoid [for if I get a choice]? I notice your 'avatar' is of 17-21, likewise mine on the flying bridge helming her. Glad you are still following; must meet up some time when convenient, especially as there is no Brighton Show this year.
Kim

[craggle]

Hi Kim, Hope you are well

Yes, shame the Brighton show didn't happen this year, was a good show. Will have to wait till Alfold or Sumners for a show I guess.

Would still love to go out on the Severn if it's at all possible. I have a holiday booked mid March but other than that, free as far as I know.

House move is something I've been planning with the other half for a while now but following a very positive valuation last night of my property, I think it will be going on the market in March sometime then we'll look for another place after it has sold and everything's cleared. Big step in life but has to happen sometime I guess. Never a good time with work though, always busy here it seems.

Sure I'll see you around the shows in the year but keep in touch if anything comes up.

Cheers

Craig.

[mk1]

Hi Kim yes my jets  do pivot on the horizontal when I started the build I looked at keeping them on the same axial as the underside of the hull but wondered if when you pivot the jet would the water start to shoot upwards and loose some of its force as it would be very near the surface so went this way to try and get the best from the jets but not correct as the proper ones they work quite well in forward and reverse it was all trial and error. The water jets on the real boat  look down at a 5 degree angle which helps keep the nozzle down below the surface. I am going to due the right way on the one I am now building I will then see if there is any difference in the way the jets perform. Will try and phone you later today.

John

[Canterbury Coxswain]

Houston, we have lift-off!
When I took early retirement from my 'forensic' work, I was asked to do some work for the National School of Government [and two other Companies] delivering Project Management training to all Government Departments, Quangos and other independent 'bodies' throughout the UK. The methodology used was PRINCE - Projects in Controlled Environments. Saturday and Sunday's work was like that - a controlled environment! The use of my Proxxon electric screwdriver came into its own. This has a small Jacobs metal chuck and can be controlled to a very low rpm usage.
Here is what I did in making the initial steps to fit the Port side water-jet:

• a small pilot hole was drilled through the centre mark drawn
• this was then enlarged to take the centre drill of a 25mm hole saw
• the hole was drilled to take out 25mm of the 31mm aperture required
• this was then enlarged to the full 31mm using a small sanding cylinder from my Dremel collection - superb, as here it was controlled to turn very slowly, giving me complete control over the amount of material [glass fibre] removed
• then I 'dry' fitted the water-jet extit nozzle from the inside of the hole and made a few little adjustments so it sat well
• then the inside of the hull was marked around the area where the intake to the jet would be fixed
• that done, I then used my Proxxon Delta sander to flatten the glass fibre and resin hull surface - this in effect gave a better surface to later key the resin and glass fibre tape support to, whilst also lowering the surface by some 1mm, allowing the whole unit to sit in the correct attitude - GREAT.
• the next step was to fit the external water-jet plate, which was stopped from being flush to the transom hull surface by the little screws and nuts holding the trim plane hinge bracket
• so I then ran a lead pencil over these items and pressed it onto the masking tape, leaving a lead residue on the tape to show their positions
• these were drilled out to accommodate them [I will later put a tape and resin across the internal surface to seal these holes off]
• once this was 'dry fitted' I drilled the four plate holes through the transom hull
• using the Dremel rotary sander removed the internal surface to enlarge the plate I was going to place inside on the water-jet exit pipe to pull the whole unit together when the four M2 black screws were screwed through [having already tapped an M2 thread to the inner plate holes]
• this all went well and I then marked the outline marking - with a black [fine point] marker - to show the material to be remove for the water inlet at a later point

Later today [I'm sitting writing this as I watch the 51st Superbowl which will end around 0400hrs. Score at the moment being New England Patriots 9 - Atlanta Falcons 28. This is a pity as I am backing the NEPs and yesterday my two Premier League teams Chelsea and Manchester United both won!] I will use the same procedure and cut and fit the Starboard water-jet.
It was good to have John [Mk1] the builder of two really nice 1/12th scratch built Shannons phone on Saturday and we had a long chat, exchanging ideas and experiences on these model lifeboat builds.
Hope this all makes sense! I will Post the supporting photos in two batches.

C.C.

[Canterbury Coxswain]

The rest of the photos, as promised. Meanwhile with just five minutes to go in the 51st Superbowl, the New England Patriots have fought back with the skills of Tom Brady. NEPs 20 - AFs 28!
C.C.

[Canterbury Coxswain]

Sorry, the last Post should have had the first photo as now here [not the one Posted], it shows the 'impressed' markings of the screw heads on the back of the plate. I'll put it down to the time 0250hrs!
C.C.

[Canterbury Coxswain]

Just witnessed Superbowl history - a draw of New England Patriots 28 versus Atlanta Falcons 28 at the end of Full Time. Therefore, the first time ever that a Superbowl Final went to sudden death in extra time [Overtime] and Tom Brady [No.12] made it happen to complete a touchdown - NEPs 34 v. AFs 28!!!!! That was at 0326hrs. What a last 24hrs.
C.C.

[derekwarner]

Kim...I am familiar, comfortable & have used a similar... PRINCE - Projects in Controlled Environments for our Australian Department of Defence

Could you please confirm the manufacture detail for the complete resilient drive shafts couplings.......[should one 1/2 or a hub element as shown not be rotated ~~180 degrees? ]

Have not received a PM yet with your land based e-mail address

Derek

[Canterbury Coxswain]

Just to say, many thanks to all those that have sent PMs over the past few weeks - they have been both helpful and encouraging.
Firstly, it was good to have had a very long chat on the phone on Saturday with John [Mk1] regarding various aspects of the Shannon build, remembering that he was the first on these pages to show a 1/12th scale model Shannon build [and it was all scratch built!] and he's now on his second one. Also my thanks to Derek [Decoy] 'Down Under' who has patiently shown me how to make my photos more focused with the use of the coloured circles around the salient points. I have not been the best of pupils, but think I have now cracked it! Hence I will 'show off' with a couple of previous photos, just to enhance what I was talking about - plus a little extra.
Secondly, John pointed out the difficulty there is in taking off the larger plastic hex heads and bolts from the cards they are attached or moulded into. They are not like the loose ones or those that come on a sprue [like the Airfix kit parts]. I had a go and found he was right, but I moved my chisel blade around a 180 degree shape under the washer - two did not work, but the second two I reversed the blade back up the right way and it worked. Then I pushed each bolt head onto my finger tip and rubbed it across 800 wet and dry paper [dry] and this neatened the bottom of the washer. Yes, fiddly, but if you need to do a lot them it is a cheaper method - you just need copious amounts of PATIENCE.
Thirdly, looking ahead I have purchased some aluminium square section tube from MACC Model Engineering Supplies Ltd in Macclesfield. These were 1/8" 3/32nds" 5/32nds" 3/16ths 7/32nds and 1/4" external dimensions. As you can see they sleeve into each other. One of the things I am aiming to do is hide my water pick-up scoop face in the front bevel of each under hull support protusion where the transom rests on the launch carriage.
Fourthly, I have now drawn a yellow circle round each of the bolt head impressions on the masking tape - there are three, four and one going left to right.
Lastly, a couple of photos of where I got to yesterday with the Starboard dry fit of the water-jet. I just now have to work on the plates and finalise it. Exactly the same process used as on the Port side.
Well, there you have it. This should have been Posted in the early hours of the morning, but my IP just seemed to 'pull the plug' last night when I wa adding the photos and I lost the lot!! [Likewise my BBCi Player and ITV Hub etc.,.]. There should have been another heading here [making six], but I cannot remember what is was on the re-type.
I hope it all works this time - fingers crossed.
C.C.

[Delboy1958]

Hi Kim
Good job on fitting the water jets nice and neat as always.

Regards

Del

[Canterbury Coxswain]

Thanks Derek. Mind you, your 1/12th Waveney was very neat too.
Made some progress today in the following ways:

• Decided to strip the water-jet units and check the assembly and lubrication, then re-assemble [just in case they get 'fired' up in the next few weeks]. Used the opportunity to clean the two aluminium brushless motor conversion flanges and also make it that both units have their wires exiting to 12 o'clock [North].
• I also decided to neaten/sharpen the 'leading' and 'following' edges of the impeller blades - just so they are slightly more efficient at up to 20,000rpm.
• One or two folk have asked after the shaft / motor couplings. These come with the units, but can be bought separately from Kehrer. They are product number KUP1 and cost Euros 8.9 each. They have a 4mm hole one end and a 5mm the other. The individual parts do not seem to come apart [they looked and felt as if they were glued in place] - pity as I wanted to re-align one of them!
• I also finished the alterations and fitting of the Starboard water-jet parts so the 'dry fit' would be complete as per the Port side one. At this point I noticed I had not put the bolt heads and nuts around the Port external plate. However, they all need to be painted silver for the final assembly, but the units will need spraying first.
• You will also see that I am using the black plates that are drilled for the three servo function holes [left/right steering and the reversing bucket operation] on the inside and not as intended by KMB externally - just a preferred choice by me.
• You can see in one photo that I have put a steel rule across the width - just thinking through my approach to designing and then milling out a Perspex sheet for the servos to be installed in; likewise to house the Rx, ESCs and switches.

If I get enough time tomorrow afternoon I will probably glue the water-jets to the hull.

C.C.

[Canterbury Coxswain]

More progress made today, but not necessarily in the direction that I had planned.
Firstly, I noticed that the areas behind the outer edges of the trim tab plates had been overlooked and will need filling in the near future - just like the real boat.
I mention next that I plan to use the 100% waterproof Gorilla glue for the first fix of the water-jets, which I bought at B&Q. It was not cheap, but I have used it on a number of small items so far and am impressed by its strength. Do bear in mind that one surface has to be treated with a light application of water and that the process causes the glue to expand by 3 to 4 times its original size. More on this when I apply it in the actual build process.
The rest of the afternoon went like this:

• I cleaned the interior stern surface of the hull with nail varnish remover [basically acetone - I think] and then put resin and glass fibre tape across the holes that were caused when I attached the stern water-jet plates
• Having done this I then noticed that I had missed the two higher edge holes! This will be rectified when I mix some more resin.
• After this had gone off, I started to mark out the water-jet bases profile and then placed masking tape on the floor of the hull so that I could ascertain that they were straight when I fix them. I used a pair of dividers to check the alignment.
• I noticed that where the internal black flange on the Starboard side was positioned had a small resin 'bump' in the lay-up, so I used my delta sander and flattened this off and also did a quick run over the Port side too.
• I then placed some rolled up tissue inside the water-jet water inlets and taped this in place with masking tape, so that when I start to drill out the hull to make these inlets I will not fill the internals of the units with a lost of dust and debris.
• Finally, I then dry fitted the units in place, awaiting tomorrow afternoon's session. I must remember to add the internal flanges before I glue them in place - watch this space...........

A reminder at this stage - please remember to watch the Health & Safety issues with both the acetone [nail varnish remover purchased at Boots the Chemist] and also the Gorilla glue. Both the effect on the external skin and the lung linings [from the vapours] can be quite extreme, if cautions on the product containers are not heeded.
C.C.

[mk1]

Hi Kim looking good  on the bit about [aiming to do is hide my water pick-up scoop face in the front bevel of each under hull support protusion where the transom rests on the launch carriage] I like this idea been looking but did not think of this area. Are you going to use both of them for the motors if so what about the ESC some of these are water cooled were would you put these pick-ups. Have been in touch with Andy and have bits coming

Cheers John

[Canterbury Coxswain]

Cheers John,
The water pick-ups will be used for the watercooled ESCs I have, see the early pages here where there is a photo. The brushless motors are for helicopters, so have a a built in fan [I'm told!] that should cool them a little, but will make a 'whine'!!
Kim

[derekwarner]

All looks sharp as usual CC...& I love the yellow highlights 

Just one concern is the use of the Polyurethane ''Gorilla Glue" in this application......I acknowledge such glues when used on porous surfaces such as wood result in that 100% water proof joint in that the wood will rot in water & finally decompose & the cured glue is intact

So with your application, you will be relying in the glue adhering to roughened synthetic surfaces, however no chemical reaction will occur apart from the foaming..........Polyurethane glues will not adequately adhere to synthetic surfaces

Having said this, a full matrix of 1.5 mm diameter holes in the square footprint of the water jet body in the hull would allow the Polyurethane glue to penetrate the holes & form the matrix of strengthening keys

A further consideration could be to install identical sized footprint wooden reinforcement plates in the hull......if these were also roughened, would allow the Polyurethane  glue to penetrate the matrix of holes & adhere to the wooden substrate

Derek 

[Canterbury Coxswain]

Hi Derek,
Did like your little 'innocent' emogi!!
Thanks for the information. Rightly or wrongly I have gone with the Gorilla Original glue for two reasons:

• The material used by Kehrer for the water-jet casing is a fibre glass filled plastic and when roughened is 'porous' and does not have that 'rubbery' feel of some of the 'awkward' plastics. This is bonded onto the resined fibre-glass [hull].
• Whether Araldite or Gorilla I was then going to resin and glass fibre tape the unit too - a belt and braces approach.

I have to say, it feels very secure, before the 2. stage has been done. I did take you good suggestion, though, and drilled out with a ball end mill little hemi-spheres, to provide the extra grip around the water.-jet inlet aperture surface.

* To anyone following this 'thread' and using it for their own build, please do not follow this 'blindly', but make your own preferred decision. For me this is a 'test' approach to a new product for me - I just hope it works. The reason being that on some of the occasions I have used Araldite, it has been given a sharp knock and that has released the bond, leaving me with two items one now having a flat almost mirror like surface, hence my trial of a 'new' product.

I hope to Post today's photos and progress tomorrow evening.
C.C.

[Canterbury Coxswain]

Well, there is a God!! When I came to fix the water-jets in place I was concerned on getting them both at 90 degrees to the transom, but at the same time parallel to each other and the the bilge keels. I took off a side bench a square engineers' parallel and laid it in the keel 'slot' at the bottom of the hull, then grabbed another one - smaller and chunkier - and laid this against the first and together they were spot on to the lines I had already drawn from the plans!! So I laid the Starboard water-jet against this and all was perfect to glue the unit in place, before later using resin and glass fibre tape to further reinforce [a belt and braces approach]. The following photos will now show the fitting of the Starboard unit then the Port one.
Just a few pointers to go with the photos and if there seem to be a lot of them, both here and throughout the thread, that is to be of help to those that are building the same model and say they are finding this approach useful [from a few PMs received - thanks].

• Just before I fitted the Starboard unit I noticed the unit was away from the bottom - on looking I noticed that the length of 'glass' tape I had fixed below was proud, so used the Delta sander to make flat.
• I drilled the hemisphere dimples on the water inlet edge surround [courtesy of a suggestion from Derek Decoy - 'down under', thanks], thus more than doubling the actual surface area of adhesion, whilst also form little locating mounds for lateral support against any knocks. For this I used my Proxxon 'screwdriver' fitted with a ball end milling bit, set onto a slow speed.
• I then marked an upright pencil marking on the interior surface of the water-outlet plate and along the unit's top edge - in a central position. this allowed me to line them up and make a small correction in angle against the upright hull transom surface. This I pencilled on. I then glued these two parts together, before fixing to the hull. When the glue had gone off I gave the two objects a good pull and push to see just how well they had stuck. I am pleased to say they appeared pretty strong [puts hands together and keeps praying!!].
• I cleaned both the hull bottom and water-jet outlet apertures with acetone...........
• .........lightly wetted both the hull transom circular hole surround and the area marked out on the hull bottom, then [this is required to make the glue start to chemically react]........
• .........applied a bead of Gorilla glue around both the internal surface of the water-jet outlet plate and the water intake edge area and fixed it into position. I pushed it downward, but the angle and position did not allow me to do what the instructions say, that is put a load or fixing tape onto the unit to give a constant downwards pressure. So every now and then I re-applied my hand pressure and when the glue started to foam [easily seen as the glue turns creamy in colour] made sure this was ongoing until the glue had gone off - about ten minutes.
• You will notice I also added cocktail sticks [cut in half] from the outside to align the M2 screw holes and to stop them from filling. One of these [bottom right] needs to have its point reduced otherwise it fouls a little circular protusion on the water-jet housing and could make you push it off centre. Make sure you take these out before the glue has fully cured!
• When complete I removed the tape in the hull bottom and a small square on the external surface where the plate will be fixed on, just so any excess glue would not bind the masking tape on and also so I could clean off the excess glue on the circular surround.
• When this was done I wetted a cotton bud and gently removed any major excess of glue, to give a neat finish.

17-09 turned up shortly after this and said how nice it looked - 'pity one seems out of line though', what a little joker he is! It did make me look though!! That said, I did keep measuring the gaps and checking the lines already drawn onto the hull through the process above, just to make sure nothing had got knocked or moved.

That's a first for me in model boats - fitting water-jets. I am pleased with the result and hope to 'glass' the units in later today.
C.C.

[Canterbury Coxswain]

More photos for the process outlined above.
C.C.

[Canterbury Coxswain]

The final photo.
C.C.

[Canterbury Coxswain]

This afternoon was the time to now 'glass in' the two water-jet units, seeing that the 'Gorilla' glue had had twenty four hours to cure. I was going to use the Isopon Fastglas resin and hardener that I had used in the earlier pages of this build. 17-09 sponsored the brushes to achieve this! My only concerns were:-

• I wanted a single, one shot approach that would look relatively neat......
• ......yet was unsure how long I would have - sometimes the resin 'goes off' quickly and sometimes, weeks later, it can still be sticky and takes months before all is fully hardened. They say on the tin 'a pea sized amount of hardener to 10ml of resin'.

The very first thing I did, though, was to drill a centre hole in each of the scribed water-cooled exhaust outlets, before I forgot and then found I had removed the masking tape and would have to measure and scribe them again.

I then proceeded with the following:-

• To give me the maximum time with the resin liquid I cut two lengths of fibre glass tape to 3 and 1/4" inches [for the sides], one at 2" [for the straight end] and one at four inches for the rounded section going under the water outlet 'tube'. These last two had a single slit cut halfway across one side [to go either side of the upright - only done on the second one as I learnt the hard way!] and the other had five similar cuts enabling it to curve and follow the line of the water inlet and hull floor shape.
• I did each water-jet individually, starting with Port side, to give me time on each and see how it progressed regarding the hardening off stage.
• Prior to applying the resin I sanded around the unit's base and up the side of the housing too - to give a surface for the resin to 'key' into.
• With the brush wet with resin I gently filled in around each of the interior transom plates and then with the resultant residue filled in the gap that makes the keel, for around 8". This will eventually make the bottom of the hull 'flatter', so any small item dropped is easier to retrieve.

All went reasonably well and I cleaned the brush each time with cellulose thinner, supplied by Elwyn Baker [given to me with lost of other model boat bits when he emigrated 'down under' to Melbourne a few years back], so still have two to use, while I await a supply via e-Bay.
Tomorrow I will attempt to cut out the two water-jet inlet apertures on the underside of the hull.
C.C.