Hi
I have obtained some old windsurfing gear quite cheap with a view to giving it a go at 65 years.
I have a ten cate spacer with a 465 mast. The 4.6 and 5.1m sails that fit fine but are in poor condition and are embarrassingly tatty.
Recently I was able to purchase a Naish Force 5m (luff 423, mast 400/19) which is in very good condition with a view to the future when I purchase newer gear. The 400/19 mast is a reduced diameter flexible mast from what I have read and it seems to me that would suit the sail perfectly.
As I am retired, I am not keen to buy a new 400/19 mast and it is unlikely to be able to be fitted to the downhaul gear, etc anyway or new gear yet until I decide if I wish to continue learning - heaven forbid...I might be too old!
It is a tight fit but is able to fit onto the mast with some difficulty, but after applying the most downhaul be hand that I am able, the leech is tight and the battens are still across the luff/mast completely, so it requires much more downhaul still.
If I apply enough downhaul to bend the 465 mast to get the battens back past halfway across the mast and some looseness at the top of the leech, will the mast or sail fail? I am afraid of putting a split mast through my torso.
I will need to use a jig to apply more downhaul as I am not able to pull down by hand any further.
As I am a beginner, I am beginning to feel that it might be more prudent and maybe a lot safer if I repair the monofilm on the old sails that came with it and keep the newer Naish Force 5m for a future setup.
Aside from my question, I am curious as to how much downhaul pressure is applied in kg to some high tension setups. Are there some figures about the limits that are generally safe?
Unfortunately i would strongly recommend you give up on trying to make that work.
the first issue is that the 465 mast will be much stiffer than the 400 that sail asks for, the second number in 400/19 is called an IMCS # and is a measure of curve when loaded, the smaller the number the "softer" the mast. This plus the extra length in your current mast make it unsuitable for the Force. Although probably pre IMCS measurement your tencate mast is likely to be around 25 which equates to a lot stiffer, back in the day some people cut down the next-size-up mast to get a super stiff righ, but you are going up two mast sizes if not more.
The second issue is trusting 20yo fibreglass not to break when it is loaded past its normal use. On a nice new mast you can happily apply the amount of downhaul pressure modern sails require, would I do it on an old faded mast from under someones house... deffo not.
it is more money but you will be so much better off trying to find a nice modern 400 mast (even in standard diameter) that will rig nocely and allow that sail to be used, and being a good solid wavesail you will get years out of it.
as for the other bits, sorry cant help there, never measured downhaul pressure. but it should be achievable on the right mast with a decent pulley and using a screwdriver or harness hook to grip the rope.
There are a few things going wrong here.
I would not use that mast with the new sail. It is an old fiberglass mast and could break. Old sails dont use much downhaul . New sails require a huge amount of downhaul. A sail like this may require over 50 kg of pulling force on the rope x a three pulley block and tackle ratio going on, could be over half a ton force on the mast ( 800 kg if did my calculations correctly ).
You can buy a winch to do this easily.
I would definately use the old gear together untill your up and running and see if you will like it.
Dont worry about tatty, thats the new retro.
Otherwise you will at least need a mast and mast base extension.
Remember windsurfing is a challenging wobbly thing to do , but soon as you get the first basics going you will not want to stop.
Welcome 
Thanks guys
I just needed a quick jerk on the reins to pull me back in line :)
I have another JV Wave 5.2m sail and is in good condition that came with the gear and just rigged it up and was easily done and fits the mast perfectly with little effort. So I will see how that goes initially but I would think that would be suitable for a beginner in light winds. If I struggle, I will use the ratty smaller ones instead for a while. 
It would have really annoyed me if I had persisted with the wrong setup and wrecked the Naish Force sail.
When you get a 400 for that Naish Force check the curve compatibility. Naishes are typically constant curve with a slight hard top bias. It doesn't have to be exactly right for a wave sail but a middling constant curve will work and it will give you a pretty good selection of other sails to chose from that will also work on it.
www.unifiber.net/masts-selector
The other aspect to this, is the difficulty of learning. Those old sails had very narrow "sweet" spot, good grunt at low winds, but become a real hand full at higher winds, so if you have very steady moderate winds you'll be OK, but gusty winds will make it very challenging to learn. The Naish (on the correct mast ), will have a much larger wind range and handle gusts much better.
Keep in mind that windsurfing gear has progressed a lot in the last 20 years, modern gear is more user friendly than your old stuff. Don't be too discouraged if you're having a hard time in trying conditions, if you enjoy it when conditions are good, it's probably a good idea to look for more modern gear, 15year old stuff is still very good, except sails don't last that long if they've had much sun exposure.
I came back after a 20 year layoff with my original fibreglass board, fibreglass mast and RAF wave sails. I had a ball. I've since upgraded somewhat and the thing I notice most is the range of the modern sails.
If someone tells you to waterstart with both feet on the board... don't.
Select to expand quoteAgrid said..
I came back after a 20 year layoff with my original fibreglass board, fibreglass mast and RAF wave sails. I had a ball. I've since upgraded somewhat and the thing I notice most is the range of the modern sails.
If someone tells you to waterstart with both feet on the board... don't.
Agrid,
That's the only way I waterstart is with both feet on the board. Sorry, I had to add my two Sence of info there.
But yeah, I never felt stable enough water starting with one foot. It was too much pressure on my knee when coming up onto the board on one leg. Much more comfortable coming up on the board on two legs in my opinion. But as we all know, there are many ways of doing a maneuver in which will work successfully.
I always say, do what works best for you, for your style and method. But try it out first the most common way, which is forward foot resting on the board and the back foot in the water, then coming up out of the water on the forward leg as the back leg then follows onto the board.
Select to expand quoteMagic Ride said..Agrid said..
I came back after a 20 year layoff with my original fibreglass board, fibreglass mast and RAF wave sails. I had a ball. I've since upgraded somewhat and the thing I notice most is the range of the modern sails.
If someone tells you to waterstart with both feet on the board... don't.
Agrid,
That's the only way I waterstart is with both feet on the board. Sorry, I had to add my two Sence of info there.
But yeah, I never felt stable enough water starting with one foot. It was too much pressure on my knee when coming up onto the board on one leg. Much more comfortable coming up on the board on two legs in my opinion. But as we all know, there are many ways of doing a maneuver in which will work successfully.
I always say, do what works best for you, for your style and method. But try it out first the most common way, which is forward foot resting on the board and the back foot in the water, then coming up out of the water on the forward leg as the back leg then follows onto the board.
Both methods have their merits. In light winds using one foot allows you to get the sail more vertical and hence get more lift. In stronger winds puting two feet on the board aids in stability
Two feet is a bad habit. It enables the board to drift downwind a little, if you are in waves with a bit of current and only barely powered, that tiny bit of drift ensures you won't get up and you will get smashed.
Further, both feet up on the board keeps the rig lower to the water so you need more wind to lift you.
Back foot first, front foot kicks to help with lift and act like a sea anchor to stop the drift.
The pull down on the boom balances the pressure from stepping up with rear leg.
This enables waterstarting in the least amount of wind.
Oops, I had the foot work wrong and wanted to clarify that. Yes the most common way is rest the back foot on the board and use the front foot to guide the board direction and help with the lift to get onto the board.
And yes it does take a little more wind to waterstart with both feet resting on the board. If I'm bunched up like a ball, I can waterstart with both feet in 12 knots of wind with my 6.8 sail weighing 185 pounds on a 115L board.
As above, but most of the time my back foot is in the back strap, that way I have more control of board direction, I can really pull the board under me. And yes if severely overpowered, I've even had both feet in the straps, and if I'm feeling brave and on a real sinker, hooked into the harness to reduce arm strain.
Select to expand quoteMark _australia said..
Two feet is a bad habit. It enables the board to drift downwind a little, if you are in waves with a bit of current and only barely powered, that tiny bit of drift ensures you won't get up and you will get smashed.
Further, both feet up on the board keeps the rig lower to the water so you need more wind to lift you.
Back foot first, front foot kicks to help with lift and act like a sea anchor to stop the drift.
The pull down on the boom balances the pressure from stepping up with rear leg.
This enables waterstarting in the least amount of wind.
Ed Zachary
