Hi boat doctor

I have got a miracle dinghy and the varnish needs to be removed (where it hasn't already pealed off). I would also like to remove the paint from the bottom of the hull as it's not the best of jobs.
Can you recommend what is the best way to remove the pint and varnish?
many thanks

Paint is easily removed with a heat gun and scraper, then a good sanding down to remove the last streaks of paint and create a good surface for primer, undercoat then gloss. Varnish can be done the same way, and when its already peeling should be quite easy to warm and scrape off, but be very careful not to overheat the wood because it will scorch and show afterwards.
The alternative is to use paint stripper which breaks down the layers of varnish or paint chemically. Wear gloves when using paint stripper and be sure to wash down the surface thoroughly to remove all traces before re-varnishing.
For either method, always scrape along the grain of the wood, never across. Carefully file the corners of the scraper so that they don't dig in and leave score marks, test on a hidden area first.

Greetings Boat Doctor,

I have a wooden GP14 but the centreboard keeps rising up when under sail. Is there some form of friction break/ rubber strip normally fitted? If so where might I puchase one and how do I fit it ? Your assistance in this matter is greatly appreciated

Vince

Dear Vince

Yes, there should be a friction brake fitted to the top edge of the centreboard, visible when in fully down position. It is usually a short length of rubber tube fitted in a cut-out on the centreboard,held in place with two large screws and a strip of metal. The screws, when tightened, squeeze the tube so it rubs on the inside of the case to hold the board in its set position. Its best adjusted on the water.

Regards

The Boat Doctor

Where can I get instructions on how to fit a spinnaker chute and fittings for a Mirror dinghy please ?

David Livingstone

Dear David

Trident seem to cater for all things Mirror, they list the chute and various special fittings.

http://www.tridentuk.com/sailing/Trident_uk_for_Mirrors9.html

Regards

The Boat Doctor

Dear Boat Doctor,

We have recently capsizied a newly aquired old GP14 and discovered that the seal between the plastic buoyancy tank and the fibreglass hull has cracked ( as it filled up with water!).

Is this possible to repair?

Thanks

Julian

Dear Julian

A good example of how fibreglass boats are not as zero maintenance as people like to believe!

Usually, in the case you describe, it will be the joint between top and hull moulding that has failed due to flexing from crew movements in the boat, or maybe from a poorly supporting trailer.
The original mouldings often feature a wide flange to create a bonding surface at that point, so its easy to see the problem when the floor is pushed down to seperate the joint. Slide a scraper blade into the gap, and move it along the joint to see how far the split extends, it may go all the way along! Its important to clean out all the old jointing resin so either chip it away or use sandpaper on a stick to clean up the surface and give a good key for the new resin. Make sure the joint can be closed up tight when resin is setting, may be easier to invert the boat on trestles then add weights to push the bottom panel back into position.
Epoxy resins such as SP, mixed with some microfibres, will create a much stronger joint than the polyester resin used originally.

Regards

The Boat Doctor

Dear (esteemed) Boat Doctor,

My dayboat (and I suspect the helm too) have attracted unflattering
comments at the club such as "doesn't look fast",  "heavy", "weighs a
ton", "tanker" , "watch out the dayboats coming!" etc, etc - I think
you get the picture. Trouble is the helm is getting a complex about
being lapped 1 or even 2 times by the speed monkeys, golden oldies,
people in nappies etc and is certainly getting a very good suntan
with all that time on the water. Being beaten by seascouts is
especially hard for (my masculinity) to take.

Can you help me by suggesting ways to spend £100- £200 to make the
boat faster -  the options are:
1. Buy go faster stripes, watch my wind indicator more, and spend the
rest on a sailing coach.
2. Buy a nice new jib ( from speed sails?)
3. Paint the hull with super duper micro molecular slippery paint to
reduce friction
4. Take out the 30kg anchor and hide it in a speed monkeys boat. Put
the money towards sail renovating liquid.
5. Sail more aggressively and "take out" lesser boats and
(especially) seascouts , by mistake of course. No doubt, the money
will be needed to pay increased insurance premiums, but it would be
worth it for the enjoyment.

As you may detect, the awful agony of coming last is taking its toll,
your advice would be much appreciated.

Yours hopefully,

The dark dayboater

Dear Boat Doctor

I have a slightly embarrassing problem. I do not want to identify myself too much but, I have a boat with mesh trampoline extensions. I need to carry out some repairs and modifications to the mesh. I need to be able to sew straight lines and to be able to go into reverse for extra strength at the start and end of each join. Another desirable feature would be a zig zag stitch; this would be useful to prevent fraying of the edges. The other feature would be that it would need to be able to go through at least four layers of material.

Can you recommend a suitable sewing machine?

PS: I did try a wig and false moustache and walked into my local haberdashery, but they were unable to help. I did however leave with some nice lace curtain material.

Yours,

A true masculine sailor.

Dear Boat Doctor,

We have a very sound mirror dinghy that was left outside for two years. So one or two areas within the boat have some water damage and have lost all varnish. Do we completely sand down the whole boat or can we just sand down the affected places?

Also have you any recommendations on how to treat the bare surface?
Thank you,
Pippa Robins

Dear Doctor L,

Many thanks for your last piece of wisdom, we have looked and discussed the various options and we feel that to enhance our fleet we will get some Oppies for the novices. We will then look at Picos for the more experienced and we will use the GP14s/Skipper and Wayfarer for groups doing instruction. I will also look at racing my GP14 on Sundays.

As our youngsters progress though we are looking at the faster racing boats so that the more experienced sailors can race at the top National Youth Level. Our youngsters have seen the Blaze and the mighty Moth win numerous races and although they are aware, that there is no substitute for the experience of both of the sailors who win the races, they would like to feel that the boats that they are racing will equal the two boats mentioned.

Could you let us know which boat they could compete in at National Youth and whilst giving the Blaze and Moth a run for their money?

As always we look forward to the Doctors wisdom.

Kind Regards,

Steven Brown

Group Sea Scout Leader

Steven and rapidly improving youth squad,

My advice would be don't worry too much about the boat yet, concentrate on getting the best out of what you have. The Topaz can win races if sailed well and up to its handicap rating! The skills are developing, but wind awareness, boat handling and racecraft are easier to learn without fighting a powerful boat. Once competent the move into a faster machine will be much easier and effective. We are seeing some good racing develop between the lads on the water and a determination to finish despite mistakes and gear failures, its all part of the fun. The RYA youth squad use Laser radials and standard Lasers, 420s and 29ers which give very tight one-design racing in a very competitive environment. That's serious commitment by youth and parents to ultimately try for the olympics. Not everyone has to go that way though, there are many other exciting classes to sail at club and national level.
Both Waggy and I learnt our skills in Moths many years ago. We both were fairly competent and experienced before attempting Mothing and spent many months swimming, but the steep learning curve levels off eventually and you become much more aware of what makes the boat go. That awareness and quick reaction makes sailing anything else easy. Only last year Waggy was neck and neck with me on the water in his Streaker, which proves that on a small lake its not the speed of the boat that matters as much as the way its sailed.

Soon it will be time for me to issue the "Moth Challenge". I have one candidate in mind, (mutterings about the moth handicap is asking for it) if he brings his wetsuit on a suitable day!

Regards The Boat Doctor

Dear Doctor,

First and foremost I would like to thank everyone at Greensforge for the warm welcome and hospitality that has been shown to the Wheaton Aston Sea Scouts.

Over the last few Saturdays and Sundays we have used the clubs three Topaz, a Skipper, a Wayfarer and a Mirror dinghy at the club. We also have three GP14 boats to bring down. Given that we work with young people aged 6 to 18 years of age and we have novice to slightly experienced sailors our group are hoping to get other boats to enhance our fleet. Can you suggest four boats that would help with the varying age groups and with the varying skills of our young people?

We have discussed this at length with other Groups and Clubs but would welcome your opinion!

Kind Regards
Steven Brown
Wheaton Aston Sea Scouts

Dear Boat Doctor,

I am using our winter break to renovate by wooden phantom, having expended much elbow grease to strip the whole ting to bear wood, do you have recommendations regarding coats to be applied i.e. preservers, primers etc before varnish and hull paint?

Many thanks
Phantom Renovator

Dear boat doctor,

How much of an effect can tuning my rig have on the performance of the boat?

How does one 'tune' the rig and the required information be obtained from?

Yours sincerely

An improving racer

Dear improving racer,

The answer of course is it depends! on how near or far from the ideal settings your rig happens to be. Some rig settings can have a big effect on performance. Mast rake for instance will greatly effect the pointing ability.
Achieving the ideal settings for your boat /rig/helm combination is important to get the best out of what you have but its only part of the story when it comes to winning races. On a small water like ours its possible to gain or lose more on a single windshift than by minor changes in the rig. However if you know the boat is set up right then you can concentrate more on making it go.

How to Tune it

I prefer to think about tuning the boat rather than just the rig. Sailmakers like to take the glory for winning and will happily quote all their measurements and settings but they sell their shiny new sails to customers with shiny new boats so the basics are often taken for granted.

The hull plays a large part in getting you round the course as efficiently as possible and hopefully keeping your feet dry. Water is heavy and if its inside the boat it will slow you down so fix the leaks. Check buoyancy tanks, centreboard case, self bailers, bungs and hatches and look for split joints or damage. Drain the boat between races if it does leak a bit until you can get it sorted.

Rudder and Centreboard (foils) are a large proportion of the underwater surface area. They should be as smooth as possible and held rigidly in use. Chunks missing from leading or trailing edges will cause turbulence and vibration even at low speed Sloppy rudder fittings can allow the steering to wander and lose feel, even breaking or falling off in heavy winds when there is more strain. In most classes the leading edge of foil should be vertical when fully down, better for pointing and lighter steering.

Attachment points should be strong and secure. Shroud plates, rudder fittings, mainsheet, jib fairleads etc should be bolted to something solid. Toe straps likewise unless you happen to like swimming. Bear in mind that older boats were not built to take the extreme rig tension often used by modern rigs so be careful not to pull too hard!

Pulley systems and control lines need to work smoothly and efficiently. Spend some money on ball-bearing blocks where there is high load such as kicker and mainsheet. Make sure ropes and cleats are suitable for the jobs. If you have to use both hands to operate something or the spinnaker always gets caught on a thingy - sort it out!

OK now we can progress to the fun bit, tape measures at the ready. Best place to start is your class association. Many have recommendations for basic setups, photos of controls and systems used on leading boats etc. Find out from the results of championships etc who the common sailmakers or builders are then contact them to get the latest information. Many sailmakers now publish tuning guides on their websites for the classes they are involved with so its easy to download, print out and keep in your toolbox.

For the Phantom i found a guide on Pinnel and Bax sails:

http://www.pinbax.com/docs/Phantom%20table.pdf there is also a more detailed description - http://www.pinbax.com/docs/Phantom%20Tuning%20By%20Simon%20Childs.pdf
and for many other classes:
http://www.pinbax.com/index.asp?selection=Tuning%20Guides

Starting with the notes at the bottom of guide, set the mast step position measuring from the transom to aft face of mast. Set the spreader length and angles as per diagram, then step the mast and measure the rake. Attach a long tape measure to the main halyard so that when hoisted it sits at black band. (upper limit for height of sail on mast) Measure and set rake with forestay or jib halyard tensioned as it will alter the measurement. Mark the position of shroud adjusters and rig tensioner for each windstrength setting, make a note of positions on your chart (eg shrouds 2 holes up at 22'2") in case marks get rubbed off on boat. It may be necessary to change adjusters or shorten wires to achieve some settings if its way out.

Of course if your sails are not up to date P&Bs there will be some differences in the settings such as outhall but if you generally follow the recommendations or consult a few other guides and take an average it won't be far wrong.

Remember these are basic settings, a guide to get the rig to perform consistantly and some tips on how to de-power in heavy winds. Once youv'e learned the tricks, throw the book away and learn from the boat itself. Its easy to get obsessed by the numbers, then instead of the excuse for a bad race being "oh its not tuned" it becomes "I went out on the wrong settings!"

Happy Tuning
The Boat Doctor