Blue Moon

[GregHBBR]

Like so many of the headlines in the papers you misrepresent the "roadmap".

There is no promise to allow any of the activities by the dates given. They are merely the earliest dates possible and the decision will come later, based on the data.

[The Q]

you did notice I put "Unless Doris Changes His mind"?

[GregHBBR]

Ah, yes, but the ever pedantic and precise me says, the dates on his road map are an just indication of the earliest dates such things will be allowed. Doris has been very clear. His mind will only be made up once the data tells him so, as there is no decision, yet there is no mind to be changed.

It is, of course, this kind of brutal Asperger's driven thinking that led to my application for an invitation to take part in the Three Rivers Race being ignored back in 2010 and I've never been invited to take part since.

It's a great shame that HSC never took up my offer to take on the threeriversrace.org.uk domain that I held and was used on the independent site that Craig Slawson, Sue Hines and I curated. Craig decided that the site was better with the "3rr.org.uk" domain. I understood that Sue and Craig had offered my wordy version to the club, but it showed no interest. I let the domain lapse in 2019 since when it's being hoarded by one of those outfits that sits on potentially useful domain names and would, no doubt, cost a king's ransom to acquire now.

[Paul H (admin)]

Greg is correct on the details, which press and public missed or ignored completely.

Its less risky to put £1000 on the 2.30pm favourite at Kempton.


Check gov.uk, as Doris told us to do. The phrase 'not earlier than' appears.

Xmas is 'not earlier than' March to July.

Paul

[The Q]

Once you've dropped off the 3 Rivers Race list that's it, as they only invite those from the year or two before.

Since those those days, the 3RR officer of the day has changed 3 times, and the OOD job has been split from the race organisation side of things. So a new request on here, http://www.3rr.uk/ will probably get you an entry.

As for this weeks work,

First weighed everything.
Trailer at back wheels 16.2 Kg each side,
Trailer at coupling, 59.9 Kg
The flat bed section, the pieces I've cut off to use, the 4 boat props and jockey wheel all come to another 45 kg. So about  138Kg there are some brackets and other small bits to add So say 145Kg being generous. I thought it was much Heavier, I'm glad it isn't.

That leaves  155Kg  spare before the 750Kg limit, so that means I can add guides, so the boat lands in the correct place on the trailer whether craned on or sailed into place. They are now being designed.

So  on to more metal bashing, the pieces I cut off were fettled, fit tested, then coated in zinc paint then coated in Top coat twice.

Then the biggest piece was joined to the section of flat bed I'd prepared a couple of weeks ago, that's 12 12mm holes drilled through 2mm Steel, then the assembly through bolted together. It's nice to be reassembling pieces rather than destructing them.

Also zinc coated were a new jockey wheel assembly, and one of the adjustable trailer to boat props. I'll need to dig the rest out from  the gardening shed where they are reposing for the moment. They'll all need at least two coats of the zinc paint..

Next week, weather permitting, I start preparing the trailer chassis to take the parts above. Most of which is derusting, zinc coating and  top coating..  Also drilling the holes to bolt the bits on..
 

[inwe]

I took mine to the weighbridge at the local tip when I built Calluna. Just weighed the total train. Came in at 650kgs. I dare say that with a few bits added it comes closer to the limit. I remember when we were designing lorries, making and then weighing. Laugh a minute. Everything that was loose came out- passenger seat, tools, spare wheel, just enough fuel to get us to the station, half the engine oil, etc etc. just for plating.

Richard

[The Q]

Originally I was worried the boat and trailer would be over the 750kg limit. But now having measured the bits,  there is plenty of spare capacity. As far as I can find out the only requirements for the new trailer markings , are date of build which is 1997, and max weight 750kg. Later build trailers need more information..

I'm torn between sign writing  on the A Frame, " Built in Saudi Arabia 1997, refurbished 2021" "Maximum Weight 750Kg"
Or a boring plate, saying build 1997, GVW 750Kg.

[inwe]

The latter seems to be a good start, don't mention SA but makers name? Possibly a serial number. Nobody's going to check it but it looks good.

Richard

[The Q]

I can't remember the makers name, he was a Brit guy  living in the same accommodation ( company hotel) I asked to build it for me.. He built them for anyone who wanted one. You just told him the dimensions and what you wanted. Then the next time off from our real work, he was out there in 50C+ welding away.. He was an aircraft certified welder so you got a good job...
His next trailer after mine was a front steering axle, 4 wheeled trailer for a sea going 30ft yacht, being built alongside my little boat. Actually the yacht was being built before, during  and after my little boat.

[inwe]

Invent a name ! and give it a serial No.
Like him I made several trailers before I retired, ending up with a nice big one ,3 1/2 ton capacity, twin axle. All I did was rivet a plate on the drawbar with GVW and a serial No. This of course was a few years before the EU directives came into force.
Richard

[Port-Na-Storm]

I thought the EU directives only applied to new trailers?

 

I know in some countries, it is illegal to use a trailer which hasn’t got a CE mark and all the rest of it but the UK was very late to bring in type approval for trailers and then only for new ones.

 

Quite a few of you have heard this story before but hey we’re in the middle of a lockdown and the nights are sooooooooo long.

When I sold the Whilly Tern to Willem in Amersfoort  he didn’t want my un-plated trailer because it was illegal in The Netherlands which is why I was stopped and questioned at UK Customs on the way back wondering if I was smuggling empty trailers into the country.  I later sold the trailer to a guy on The Broads and as far as I know its still going.

 

Q I think you will find you are renovating an old trailer and so it shouldn’t need a plate.

I bloody well hope so as I’ve got two sitting outside neither of which has a plate on it.

Go on, tell my why I’m wrong?  

 

Sent from Mail for Windows 10

 

From: [hidden email]
Sent: 01 March 2021 22:09
To: [hidden email]
Subject: Re: Blue Moon

 

Invent a name ! and give it a serial No.
Like him I made several trailers before I retired, ending up with a nice big one ,3 1/2 ton capacity, twin axle. All I did was rivet a plate on the drawbar with GVW and a serial No. This of course was a few years before the EU directives came into force.
Richard

If you reply to this email, your message will be added to the discussion below:

http://uk-hbbr-forum.967333.n3.nabble.com/Blue-Moon-tp4031096p4032152.html

To start a new topic under General Discussion, email [hidden email]
To unsubscribe from UK HBBR Forum, click here.
NAML

 

[The Q]

Depends on the date of build of the trailer, I have one pre 1982 and it needs nothing marked on it.
Over the years they gradually increased the requirements. Though mine 1997 only requires the date of manufacture. Most of the pain came in, in 2013 when the IVA became a requirement.

Now if you build one it needs, as far as I can find out, though sources are a bit variable on this..

Who made it,
Serial number,
Date of manufacture,
unladen weight
max laden weight.
and if more than one axle the max weight for each axle.

Then of course you'd have to take it along for an IVA.

So I've been careful not to alter the chassis, as that brings you to the same as current rules and requiring an IVA.

The point of putting a plate on and updating to the  modern amount of information correctly, is the less likely plod is to start questioning about it.

Actually I'm now moving towards  double marking it, one formal plate with the above modern information.
and a second plate .

Trailer for sailing boat,
Blue Moon,
Built KSA 1997,
Refurbished GBR 2021

[The Q]

This weekend's trailer work..

Went to remove old axle, hubs in the way, try to remove Castle nuts.. No chance , heat, hammering long arms on the socket.. Nothing would move them.. Then I realize I'm not using them again.. Out with the angle grinder, two 1mm thick cutting disks later on each castle nut and off they came..
After that it was an easy job.

 Then turned trailer over much easier without the old axle on board..

I then placed the New Axle in place and....

Cogitated... for some time, Measured, cogitated, measured again... and thought about it.

Conclusion, put the axle in the place of the old one, don't move it forward by 3ft ish so I can tow the oat bow forward, it would cause to many other problems and of course an IVA..

Positioned new axle, measured, adjusted, measured, adjusted, wandered off did something else, came back and remeasured.. Yep it's in the right place, marked up new axle for the new bolt holes, checked the markings again... and again.
Took axle inside and drilled holes, working my way up to 16mm in two steps.. A new set of quality drill bits made life a lot easier..

After that it was wire brush in the angle grinder, and start derusting the trailer... 1.5 hours later 2/3rds of the bottom and sides of the tubes done. Back beginning  to complain.. So stopped at that point and coated  what was done with zinc paint..

Meanwhile on the main road 3 miles from me this went past from the builders to the south coast..
STARBOARD!!!

[The Q]

Well this weekend, trailer work didn't get much done mostly due to 50mph winds and horizonal rain.. So no work done on the Saturday.

The holes were drilled for the new axle, then I offered up the bolts... Yes they did go in, But, I've not allowed enough for the thickness of the washers (2X 2mm) So I've ordered, the next length up. Should arrive today.

Then the forward bit of the triangle plus the coupling arm was derusted,  painted in zinc and the rest of the trailer was given it's second coat. I've taped over the holes in the chassis to keep the rain out until next week. I also ordered some plastic caps for the end of the axle tube to permanently keep rain and mud out.

Meanwhile thought have been going on about the rudder MK3, the one I have is MK2

MK 1 was way to short and with the boat pitching in the sea left very little in the water. Whilst I kept control it was only just, so I built MK2

Since MK2 was built, I've learnt a lot more about rudders, I've probably gone too far the other way. The length is correct but the width and span to big..

The MK2 rudder shaft is a piece of scaffolding pole, that's all I had available at the time, the whole rudder is very heavy. But it will be used for the first season at least to see how I feel about it's control of the boat.

So I've been searching through what I've got, and..

There is some 30mm diameter, 3mm wall Stainless tube, that will allow a significant  reduction in width.

There is  glassfibre, lots of..

There is stiff Extruded Foam resistant to resin..

So all the makings are there.. design has been started.. I came across tubercles which is an interesting Idea and am considering their relevance to how this boat will sail.. That is:

Generally smooth water,

With Blue Moon being so narrow often at a good heel,

Max speed 6 mph,

A lot of tacking on narrow rivers..

[Paul H (admin)]

Q,

Regarding rudders, everyone asks why MilliBee's rudder is so big on a 14ft pocket cruiser, then after lifting it suggesting weight could be saved by trimming it down.

Graham made a shrewd comment - there's a reason the rudder is big on a coastal cruiser.

Regardless of waves it keeps working, tacking is flawless unless I read the wind wrong.

It's horses for courses, but I'd think a decent sized rudder is useful for fast tacks along a narrow river in the mythical wind. Lighter is good of course.

Paul

[The Q]

Yes, there is something to be said for a large rudder especially if you have to waggle it for a bit.
The various bits of research have said she needs between a 1.3 square foot and 2 square foot of rudder in the water. Some say 1% to 2% of sail area, others 5% of hull under water profile,

MK1 rudder was about 1.2 square foot but short, so when heeled, I suspect too much was out of the water.  That's about 1% of sail area if fully immersed.

Mark 2 rudder is the maximum depth I'd want to go, which is 2.5 foot draft, that's about 6 inches less than the keel and it's up to 18 inches span.. About 3.5 Square foot,  or around 3% of sail area..

Mark 3, if the MK2 rudder does give the right amount of grip on the water. Then MK3 will just be replaced by a lighter, thinner, better built rudder, but a similar profile.
If the grip is too much or "dead" then MK3 will have the area will be reduced to 2% ish, and be lighter and thinner..

[The Q]

During the week I overdosed on aerodynamics and hydrodynamics. Amazing amount of wing and tail devices used on aircraft over the years that would not necessarily work on boats and even less likely to work on Blue Moon.
I did come across three very useful articles in Proboat magazine issues 98, 99 and 100. (Available online) This gave a series of formula which I entered into a spreadsheet..

So the Rudder should be 2.5 square feet. That's 2% of sail area and or 5% of the block area side view of the boat underwater.
The shaft works out to be just over 20mm of 1.5mm side wall stainless.
​​​​​​​Note, a 4X safety margin is built into the formula.

So MK 2 rudder is approximately 50% over size, the shaft is well over 200% over size and 400% over strength.

The 30mm shaft would be 100% over strength and 50% over width.

As for shape, draft limitations mean a long elegant rudder is impossible, instead the starting point will be a 1ft by 2ft 6inch a fin, with limited shaping. Hopefully something like a Kucheman tip, but without carrots.
As for its aerofoil a plain NACA 00 series will be used, , I've seen recommendations anywhere from 0009 up to 0025!! I will however choose somewhere around 12 or 15%.

 The nearest commercial  rudder shape  I can find would be something like a Jefa RUD26,

  https://jefa.dk/products/rudder-blades/ 

though I'll probably keep the aft edge straight for ease of construction

And so to this weekends work,
The new axle, was fitted with sealant between axle bolts and chassis. The forward triangle of the trailer received its second coat of zinc paint. The coupling was greased.

After that the keel progressed from outside the workshop down to the boat, where it will sit for a couple of weeks before, the boat is lifted another couple of feet to get the keel under.
I needed a rest after that and my left elbow is complaining badly about shifting such weights..

Then the great parts search took place, all the various pieces of trailer new and old were collected together, I eventually found the hubs in a box containing blocks cleats etc.. I know I didn't put them in there.

I also found the Makita 1/2 sheet sander I'd been looking for for ages, it would have made sanding the keel much quicker.. Still it's found now, so it will be useful for the final rub down before anti fouling.

In other things, another shelving unit was fitted in the house, and a pile of blanks for the shelves of the next two units.

[The Q]

Morning All,
Not a huge amount of work done on the trailer,
Axle bolted up tight,
Trailer turned over,
Top surfaces de rusted and given one coat of Zinc paint,
Bent over to do one area on the back of the trailer which uses C section steelwork, while trying to get at the inside to derust, my back went..
That ended work on the trailer for the weekend,
Except for one small piece that was done on the work bench on Sunday, a section of tube was cut to size derusted and painted with zinc, this will reinforce the "table" that the keel will sit on.

More overdosing on rudder and keel hydrodynamics during the week, led me to model boats and aircraft. Seemingly a model Aircraft wing operates from an Re of 20,000 up to, flat out down hill, Re 500,000, just what I'm looking for. So I've found a university paper on model Aircraft wings.. It compares the wings in a wind tunnel in the USA and from results from one in Germany, there are 60 wings discussed unfortunately without showing their foil shape, So I'll have to look each one up and dismiss any that are asymmetric. Then consider the results.

En-route to that, I found an interesting discussion on the MS15 /MS12 (as used on the Extra 300 aerobatic aircraft) aerofoil verses the J5012 foil.
They are very different,
The MS15 having it's widest point just 18% from the leading edge, then straight back to the aft end.
The J5012 having it's widest point at 35% but otherwise a more normal hydrodynamic shape..
From all accounts the MS 15 is a better foil shape for lift, but more drag until the flow separates, then it loses all lift suddenly, the J5012 is not quite as good as the MS15 for lift, but has less drag and a much more gradual separation.
The J5012 having a much better Drag coefficient than a NACA 0009...

The MS 15 seems to recover from a stall more rapidly. That would be good for Blue Moon with the amount of tacking she will do, especially on the river there are always more throw the rudder over occurrences, than sea sailing /racing. On the other hand The J5012 might be more controllable the rest of the time..

Still a lot more to research, when I have the time.

[The Q]

The Club I sail at has put up a new advert on its home page,  so here's some pretty pictures of our sailing, that you may find when you visit the broads. Especially regatta week 31st July 2021 to 6th Aug 2021, and 3 Rivers race 5th-6th Jun 2021. But they are out every Sunday and some Saturdays.

https://youtu.be/6Lm75BEMQHo

[The Q]

Well another weekend with more trailer work, some of which during a 50mph gale plus hailstones!!!

Rudder plans drawn Up, MA 15S foil discarded, just to risky to use a shape that lets go too quickly.

The flat top frame is now secured.
Then the chequer plate top, was derusted and screwed to that.
Both suspension units are fitted, hubs fitted to that, then wheels.
The trailer is now sitting on two wheels at the back and still on a block at the front.

Hit a major problem, I don't know what steel the builder used for the main chassis tubes, but it's eating my drill bits. Now on order a set of quality cobalt steel bits (1-13mm), so I can drill through to fit the jockey wheel.

Left to do on trailer,
Fit sides and front to flat top, to keep keel from wandering during transport.
Fit boat supports, which won't be done till boat is on crane, but weight on flat top.
Fit mud guards,
Weigh the lot.. with and without boat on trailer.
Make new trailer weight plates and fit.