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[bigbloke]

thanks for the offer Ramon.

I've lashed up a temporary "loop" of stiff wire to keep me afloat but i plan to do the same as yourself and replace them with all metal ones.

I noticed the starboard side had also cracked but has not yet broken through.

which make of deck eye did you retrofit please ? nylet? or somewhere else ? if the centres are the same it makes sense not to create more holes and i'll order half a dozen!   

yes one of the two steel spreader mounts  has snapped several times and has been epoxyed back together . one spreader arm actually dropped into the silt of the pond but i got it back with a powerful magnet from a broken car radio antenna base that i keep for such events (larkshead knotted to a multi-thousand foot reel of kite string!)

I have 2 thoughts on replacing the fittings:

option A)  to  replace the steel rods with tubes which i will thread on the inside,  then drill out the mast and pass through a short length of threaded bar (screw shank) which will have a nylock nut either side of the mast , leaving two open threads to screw the tubes onto

option B) to see my friend who has a lathe and comission him to make me two "cups" which will screw to each other through the mast and will be internally threaded to take the steel spreaders (which i will tap to the ID of the cups)

my friend lives about an hour away by car so option A) will minimise my carbon footprint :)

regards

BB

[mrpenguin]

@BigBloke:
Re your spreaders - not sure what your mast is made from - this may not be relevant if yours is carbon fibre....
Have a look here, about 1/3 down the page (search for "spreaders")
http://www.rcsails.com/rigbuilding.html

[Ramon]

Hi BB, Mr 'P',
 
The masts are extruded aluminium of flat section Mr P.  The spreaders I was referring to were those facing forward at 45 degrees or so for the topmast tension - not sure what they are actually called - not those for the main shrouds. This top spreader is a very basic plastic moulding which really isn't strong enough - both ours broke in transport. Maybe yours BB, didn't have them fitted - Sues boat is running without them.
 
I dont know if there are any commercial deck plates available that will suit the recess but I made them from a small piece of ali tee bar...

 
One of the more negative things with the 'fittings' I've found is that the screws, screwing direct into the un-reinforced fibre glass, can easily strip a thread and soon become very loose. I have solved this (so far that is) by epoxying a strip of hardwood beneath the deckplate areas.  It's obviously awkward to get at so I did this by threading a chord through one of the screw holes in the deck pulling it out of the hull with a piece of bent copper wire. This was passed through a hole in the reinforcement then back through a second hole with plenty to spare - these holes predrilled to match those in the hull and suitable for the screws to bite into. Another line was passed through the second hole in the deck, brought out and attached to the first - enabling the first line to be brought back through the second hole. The block was smeared with epoxy then the lines pulled tight - to bring the block up to the inside surface and in place - and then taped to the hull until the epoxy had set
Once the epoxy had cured the line was pulled through and the deckplate screwed into position - very sound - so far    - I'm keeping my fingers crossed the backstay won't need doing which might be a lot more awkward to do.
 
 
For the main spreaders I like your idea of a hole through the mast and a small piece of threaded rod to replace the main spreader/shroud attachment - simple, effective and practical. Don't know if you're doing it but this could also retain a wire shroud connection too. I've already made ali attachments but if I hadn't would definitely adopt this idea 
 
Hoping to 'get some in' tomorrow
 
regards - Ramon
 

[mrpenguin]

...For the main spreaders I like your idea of a hole through the mast and a small piece of threaded rod to replace the main spreader/shroud attachment - simple, effective and practical. .....

regards - Ramon

@Ramon - no need for the rod to be threaded - the shroud tension holds the tubes on the wire. Just push the wire through the mast and pop the other side on  as you rig the boat pondside.... works for me... The only real tension on the spreaders is compression in any case...

[triumphjon]

although a different yacht , my old kyosho seawind had speaders which were held onto the mast by two small self tapping screws , the actual spreader was a section of flat alloy bent at 90 degrees where it meets the mast ( one each side ) the mast is a groovy one so an oval profile . the mast and sails are now fitted to my brother in laws mrp australia 2 , the hull is long gone ! jon

[bigbloke]

@Ramon - no need for the rod to be threaded

agreed....but three times I have almost lost the spreader bar now and its getting tiresome. it almost always pops transporting between pond and stand. the threaded bar idea was born from frustration rather than mechanical need.

even the manual says to glue the wretched things in !

no sailing this weekend due to family commitments sadly but maybe an extra hour in the week now the clocks have gone forward.


regards

BB

[bigbloke]

snuck out late on yesterday for a crafty hours sail on the pond "across town". Well... I've got to
make the most of the extra hour!

Although light on arrival the wind soon started to gust up significantly and true to
form the damned port spreader dropped off ...this time in the middle of the pond

so that's it !!  war is declared on the main spreader!

last night I ordered the brass tube

tonight the mast gets drilled and the stainless spreader mounting bar gets fitted

already dug out the tap and die set .

I will however need to make some additional small plates for the lower stays to attach to

it did serve to confirm however, that lowering the Jib-boom-to-deck distance has improved,
but not cured the snap weather helm!

Meanwhile the temporary-replacement-for-the-broken-deck-eye has been replaced
with much stronger fishing swivel and a loop of bridle line . until I can order in the new ones

at least I have the restoration boat to work on now whilst not sailing :)

Regards

BB

[bigbloke]

PS Also got some wood to make a decent solid fold up stand - the factory one is going !

[mrpenguin]

@Bigbloke:
It strikes me that there must be something going on with these spreaders.... By rights, the spreaders should always be under tension so there should be NO WAY they can "pop out"
I saw on another forum that the rigging is considered to be very poor on the Focus. If it is like many of the other budget boats (eg Monsoon, Hurricane), the rigging will be very stretchy, causing all sorts of grief.
The usual remedy is complete replacement of the standing rigging with 100lb or better Spectra or Dyneema (expensive in fishing shops but available cheap on eBay) like here: http://www.ebay.com.au/itm/top-class-DYNEEMA-braided-BRAID-Spectra-braid-orange-Fishing-Line-6lb-100lb-/380502856534?pt=AU_Fishing_Clothing&var=&hash=item5897bcd356 for under $10 - Available in lots of colours. I have bought this item from this particular supplier no problem.
 
 
 

[Ramon]

Hi BB, Mr 'P' et al,
 
Mr 'P'
The spreaders supplied are no more than a steel rod that plugs loosely into a plastic housing held only by the shroud tension which sits in a shallow groove at the outer end.
Our two boats have had all the rigging replaced by 100lb Dyneema but this will still occasionally slip that groove during sailing. If it does with the housing as supplied you end up with BBs situation. As said before I made new shroud plates and threaded the spreaders to screw in but Malcolm our other Focus owner replaced his spreaders with ally tubing and captures that onto the shrouds with a bent piece of wire that plugs deeply into the tube. If they do come out the spreader just slips down the shroud.
 
I found a very nice small and short swivel attached to a small LED torch for £1. 25 at a local store which has now been transferred to the jib - remains to be seen how it will last but first appearances give the impression it's stong enough
 
After a five week gap finally got on the water on Saturday - It was like starting all over again - well out of touch 
then the transmitter died so I spent the day watching Sue. Not sure what was wrong with the tranny, the LED flashed alot before finally going out. Changed batts but nothing. Brought it home, recycled everything and it would appear that the LED has a faulty connection as testing the current today and poking the probes on it began to work again. Couldn't re-solder it as my iron is way too big - know a man who can though
 
Regards - Ramon

[bigbloke]

Yes well aware of spectra and dynema and the joys of braiding lengths of it back together 

I have quite a few hundred metres of both here in fact !  mostly bought in the nineties / naughties
from 35 Lb for indoor flying / zero wind flying of icarex ultralights  through  to 500Lb  breaking strain
for my big Parafoils (dual and quad line kites for buggying) I've been a kite maker and flyer for around
40 years - it used to be cheaper than RC  )

because of the difficulties (by design)  in knotting either line type I don't consider it really the most effective
for mast rigging, and hence I use 130 Lb break "climax" bridle line :

http://www.climaxlines.co.uk/

which can be both knotted and heat sealed .

it also has the advantage that if you want to mark off a preset position you can "pick" the white inner through the
black  outer, "flash" it with a lighter leaving a white marker, with no appreciable loss in overall strength.

I agree though the rigging supplied with the yacht was VERY inferior, but the brass rod arrived in the post today
so by bedtime tomorrow I will have rock solid, nylocked and threaded spreaders that will resist falling off by design
:)

the mast being "pill-shaped" in cross section does have a tendancy to bow and with the aluminium crane can actually be
a bit top heavy

Dont know if thats what contributes, but its history now ! :)


regards

BB

who is measuring up for a new "suit" of sails or three - dont like the printed artwork on the stock sail

[bigbloke]

Right! halfway there

Quick diagram of the new main spreader arrangement (attachment)

basically the shank of a long stainless bolt was passed through the mast section and nylock nutted to the main mast

two lengths of brass tube were cut and internally threaded so that they would fit onto the steel bolt. there are lovely and rigid

I found two other cheese head slotted stainless screws with the same diameter head as the brass bar

I took two 6mm lengths of brass bar 1mm less than the OD of the main brass tubes , slid the first one over the shank of the "swivel screw" , then internally  tapped the
second one to the thread of the "swivel screw.

finally  I pushed in the assembly and carefully applied cyano glue the OD of the piece of brass bar nearest the swivel screw head.

This provided a nice neat "slot" for the rigging to slip into but if I need to tilt the mast to reduce weather helm etc then the angle of the "slot" is always optimal to the
rigging and cannot pop out of the end of the tube.

The new sails are on hold as the white ripstop I have here wasn't of good enough standard to use . more ordered

regards

BB

[bigbloke]

Well the main sewing is done on the new "A" suit

final rigging after getting the fittings after work today

I have to say that 30+ years of kiting and kite-making weren't as much help
as I had though they should be and the future "b" and "c" rigs will be made
more like the jib and applique any detail on !

But on the plus side Ive learnt a heck of a lot ! and will probably make a new A suit
after the B and C 

Just don't look too closely :)

regards

BB

[mrpenguin]

Nice looking sails!!!!
I avoid sewing by using double sided tape - works great, quick and easy, no puckering when you get the tension wrong. It is very very sticky, no chance of it coming apart...
I use this:
https://www.radioyachtsuppliesaustralia.com/products/Double-sided-self-adhesive-tape-6mm-%28sail-seams%29.html
 
 

[bigbloke]

Using the IOM chart kindly Supplied by MrPenguin (thanks again) in another thread, I calculated
the vertical and horizontal scaling ratios between the IOM A, B and C Rig.

I then took extensive measurements off my factory sails, input them into excel ,
and calculated the corresponding dimensions for scaled "B" and "C" rigs for the
Focus.

I decided to make the "C" rig first as it has been absolutely h-o-w-l-i-n-g here for
quite a few days, and I had a few "offcuts" that I wanted to use up .

Still a work in progress but the C rig is going to look soooo tiny against the A rig mast :)

{The picture below is of the factory "A" mainsail and my "C" mainsail - no its not the jib! :) }

Regards

BB

[mrpenguin]

Yes the C rig looks small but that would be correct.
 
I made a B rig for a similar boat using the same information and that looked odd with a foot of mast above the sail, but it was great in a blow - not so good in light / changeable conditions of course. I managed to source another mast and cut some off it, looked better and was perhaps a bit better as there was less weight up high.
 
The other trick is to make the sail sets easy to change. These luff rings from Tower Hobbies are great for the mainsail
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXAPKT&P=7
For the jib I have a separate boom for each sail set - easier to swap the jib with boom attached I found.
 

[Ramon]

Hi BB - you've made a nice job of those  . We are on the cusp of doing likewise but I have my head down into another non related project at the moment which needs to be finished first before I can give this some focussed  (oops !) attention.
 
Keep us posted how the differing sets work out - I noticed this week last just how much snap weather helm this boat suffers from - as the mast is pretty much fixed in position from what I read I think the only way to deal with that will be to make the mainsail slightly less wide or the jib slightly fuller. Any thoughts on that Mr P?
 
We enjoyed our first race day, we came where you would expect but we did enjoy ourselves 
 
Regards - Ramon

[bigbloke]

 I noticed this week last just how much snap weather helm this boat suffers from - as the mast is pretty much fixed in position from what I read I think the only way to deal with that will be to make the mainsail slightly less wide or the jib slightly fuller. Any thoughts on that Mr P?

Yes its interesting in that the chart from Mr Penguin suggested that for IOM the maximum
permissible foot width for the A suit mainsail was at the time  (if memory serves) 360mm ?

I noticed that the focus mainsail is noteably wider for the same length of hull - my data below reflects the dimension differences

key to table:

top of mainsail (width = near to zero )
|
|___  3/4 height width
|
|____  1/2 height width
|
|______ 1/4 height width
|
|__________ base width

format of data = <dimension (from above diagram)> <IOM typical values (2003) > <focus values (2013)>


base width :             350-360          410
1/4 height width:      305-315          355
1/2 height width       235-245          275
3/4 height width       135-145          182

I have yet to try the new "A suit" Sunday will be my only opportunity probably

Hopefully I will have the "C" suit finished by then just in case . Were pounded by the atlantic winds here and I dont
think the A suit will like 20mph ++ :)

regards

BB

[Ramon]

Thanks for that BB. That would seem to confirm the thinking is possibly some way in the right direction. I was looking at the Thetis design on the Nylet site the other night and could not but notice how proportionately different the sails are to one another on the Focus to those of the Thetis
 
Weather looks good here for tomorrow - fun sail only for the Focus this week. Racing for the first time was not as stressful as anticipated though and we both enjoyed it. 'Should have done this years ago'   
 
It would appear we now have five Focus in the club but so far have only seen three on the water.
 
Ramon

[bigbloke]

based upon the Chart from Mr P, and assuming I have my formulas right:

A suit to B suit height scaling factor = 0.7375
A suit to C height scaling factor = 0.55
A suit to B suit width scaling factor = 0.9714
A suit to C suit width scaling factor = 0.8889

regards

BB

[mrpenguin]

...- I noticed this week last just how much snap weather helm this boat suffers from - as the mast is pretty much fixed in position from what I read I think the only way to deal with that will be to make the mainsail slightly less wide or the jib slightly fuller. Any thoughts on that Mr P?

Snap weather helm is always a bit of a challenge, particularly when you have few adjustments available to you. It is caused by the sails stalling - however the jib stalls first, leaving just the mainsail driving - this turns the boat into the wind

A few suggestions:
1) Sheeting angles - typical rule of thumb setup for the booms is to haul the sheets right in, then set the booms so the main boom points at the transom corner and the jib boom points at the shrouds. I have found that having the jib boom a bit closer (eg pointing halfway out to the shrouds) will reduce weather helm (keeps the stall points closer together)

2) Mast position - while the mast foot is fixed, you can still move the top of it - moving the top of the mast forward 20 or 30 mm helps reduce pitchpoling (submarining) when running downwind and would also reduce weather helm.

3) Sail foot tension - get this about the same for both sails - there should be about 20mm of curve in the sail foot. Flatten the sail more in strong weather, curve it more in light winds

4) Jib leach tension - if using a topping lift ease it off or remove it in strong weather, also increase jib halyard tension to keep the sail reasonably flat..

There is a good IOM sail tuning video here that may be of value. You may not have all these adjustments available directly.
http://www.youtube.com/watch?feature=player_detailpage&v=5JaeKpDvMl8

Another excellent one on sail tuning a Micro magic is here. While smaller, the principles are just the same:
http://www.youtube.com/watch?feature=player_detailpage&v=mwk8DTptrwY

Hope this helps
 

[bigbloke]

word to the wise .... DON'T try my direct scaling approach for the Jib sail !   


It just doesn't work 

There's not enough "pull" on the back of the Jib to keep the boom elevated properly

I'm going to pick up some card from "The Range" later and re-model it based upon the revised angles Ive come up with
by "wire-framing" the jib boom "in situ"

mainsail doesnt seem too bad though

regards

BB

[bigbloke]

Good news and bad news today....

Delighted to report that the new "A" sails seem, by pure fluke not engineering design,  considerably better.

The 60 degree angled stripes (french seamed) naturally stiffened the sail so that it "hangs" with a natural curve
and produces different "twists" in the lower and upper parts of the mainsail as a result.

At the same time it did mean that when I tried to push the luff into the mast slot the first time it wouldn't go 
so I needed to add a "luff pocket" (folded "v" of fabric ) to the leading edge. I was slightly concerned that the extra weight
would slow things down more but no such issue it seems to be flying!

However...The blasted sail servo wound out ...and promptly didn't wind in again 

I ended up sailing to day by manually winding the winch in 2/3 of the way  and just sailing using the rudder.

Ramon, how did you manage to get the sail servo out ? the back screws are practically hidden by the winch drum.
I take it the drum comes off first then the servo ?

anyway time to follow your earlier post and visit the servo shop I think.

Heres a pic of the focus on its maiden voyage with the new A Suit

Regards

BB

[Ramon]

Hi BB, Mr P,
I was out most of yesterday and watched the box last night 
 
Firsts BB good to hear you are pleased with your sails - we are still debating what to do but think before we have any made will do tghe same as yourself.
 
Sorry to hear your winch has gone - as you know mine gave in quite quickly but Sue's is still going strong. I now have a Eurgle fitted but it ticks all the time -built in morse code distress signal. Yes you need to take the drum off first to get at those screws.
 
I found the service and price at the Servo shop extremely good - just be aware that the Hitec servo is considerably bigger than the normal size and that you will have to modify the servo tray accordingly - I haven't given this any thought at the moment - but it shouldn't be too difficult apart from the access problem.
 
Thanks for the suggestions Mr P. I don't want to appear dismmissive but I have tried all you suggest to combat this (SWH) characteristic but your comment on the sails particularly the jib stalling speaks volumes.
 
I have experimented with sheeting angles but this does not seem to have a great effect nor does raking the mast forward make any significant difference to it either.
 
We had quite calm conditions yesterday with the odd small turbulence, even under these conditions the boat is trying to veer and needs constant rudder input. Malcom one of the other Focus owners has increased the area of his rudder by 1/4" on the LE and 1/2" on the TE, nothing on the length. It is also approximately twice the weight but has apparently not had a detrimental effect on the trim. He didn't have it out yesterday but said he'd tried it during the week under windier conditions and this had improved this tendency considerably. The more I look at other boats - particularly the one metres and MH'ds however the more I feel drawn to the fact that the sails are out of 'balance' (?) - far too much mainsail to jib area.
 
It'll be a week or two yet before I can give this total attention and do as BB, making new sails to see if this theory stands up but until then thanks for the help Mr P and hope you get your winched fixed asap BB
 
Regards - Ramon
 
 
 

[bigbloke]

found some 6v,  55g heavier rated (9 kilo) 4 turn winch servos for about 15 notes each

allegedly they're the same footprint as the king Max SW4805-4PA fitted to my focus

ordered a pair (component-shop.co.uk who I've had excellent service from over the years)
so will pass on their performance when they arrive.

Regards

BB