I am trying to remember what I saw when I looked into the base of the mast recently but I only remember seeing two blocks up top and then the DH line coming in one side of the mast to a block then to the other side. This is diffrent than the int DH on my prev boat.
Sorry, no help. If I had my camera with me then I would have taken pics but it would have been difficult.

Here you are :



Wouter

yep, thats it.
I take it there Is a becket that the other end of the red line is attached to on the block inside the mast to the left

Yes,

Basically it is a three stage cascaded setup.

First stage (blue line) is a 2:1 with a nice soft 5 mm swiftcord line or something. You'll be holding this line in your hand.

The second stage (red line) is a small diameter and very flexible high tension line like 2 mm D12 or 3 mm dyneema. The purchase here is 3:1 making the total internal setup a 6:1

The third stage (green line) is a 2:1 system with a 4 mm dyneema line with a tough outer mantle. This is needed as it does rub against the goose neck or other components a little bit. And it is out in the elements (UV radiation etc).

The internal 6:1 setup followed by the outward 2:1 setup make for a 12:1 setup overall. By using the different line diameters this setup is cheaper and runs more smoothly then any other downhaul setup. This is especially so since most of it is inside the mast and thus well protected from weathering and salt.

Wouter

Thanks Wouter ... and the other end of the blue line comes out the opposite side of the mast.

Good Luck this week at the GC.

[/quote]

I'm interested in building this. The internal crosspiece will carry a huge load. Questions:

1) How far up the mast is the internal crosspiece?
2) Is that crosspiece really "Z" shaped? What is it made of? How thick is the stock material?
3) How is this crosspiece connected to the mast, rivets or a bolt all the way through?
4) The drawing is just a schematic. In reality, could one or two of the internal blocks be a double or MUST they be 2 singles to achieve the cascade effect? First, the 2 on the crossbar could certainly be a double, right? Although only one single is shown for the blue, there must be another that is not shown. Could that be a double? That one might be too close to work as a double, space wise. Hmmm... Wout?

The top blocks can be replaced by a double but the two floating ones must be independent. Think about it: as you pull on the downhaul the blue/red block goes down and the green/red one goes up. If you attach them together, nothing will work.

Why do you think there is another block for the blue line? It's just entering by one side of the mast, going up to the block and down to the other side...

On my Blade the "z" is a stainless steel bolt inserted through a piece of aluminum tubing, inside the mast. It is about 62" from the base plate.

Pictures follow.

another.

another

last one.

The comment about the other end of the red line is still a question. Going back to a Wouter post from 2005 I found this drawing.



I'm guessing that this is NOT what is the photo from THIS thread. PTP's comment above says a lot.
"...there is a becket that the other end of the red line is attached to on the block inside the mast to the left."

This latest setup is simpler and 12 to 1 compared to the old photo I've shown here.

David,

You are showing the diagrams of two cascaded downhaul systems that are on the OUTSIDE of the mast. Often seen on F18's. This is a 2-stage cascaded setup

F16's however predominantly use the internal downhaul system which has a significantly different diagram as it is a 3-stage cascaded setup. See the diagram in my own earlier posting.

Wouter

OK, last question (not!). The green external 2 to 1 exits the mast, goes up and around a block on the tack of the main and down to...what? A clam cleat or an eyestrap on the mast? That would complete the last 2 to 1 cascade, right?

That means there are 3 exit blocks on the mast, two that lead through the mast, into cleats, and on to the sailor's hand and a third for the green to the tack cascade.

So the entire inventory of needed hardware is

1) a double block on the crossbar
2) a single with becket for the green to red
3) a single for the blue internal
4) three through-mast exit blocks
5) two cam cleats
6) stainless bolt and tube for the crossbar.
7) clam cleat or eyestrap for the end of the green.
8) appropriate lines.

Sound about right to you folks? Any of those blocks need to swivel?

Pete, thanks for the 62 inch measurement (1575 mm). I would never have guessed it was so far up the mast!

You're welcome. The next time I pull it apart, I'll take some pictures of the inside.

I used just an eyestrap ti which I tie the green line with a slip knot. Like that it comes off very easily even when alot of downhaul tension is put onto it. Jam or cam cleats tend to let the green line slip or strip the mantle of the core. Eyestrap is best in my opinion. The VWM Blade has a sail hook on the end of the green line that hook into a hole on the base plate.

62 inches sounds like alot but with thsi 12:1 system you can REALLY downhaul your mainsail. I'm getting 5 to 6 inches of downhaul between tensioned and fully tensioned. When the sail is slack it is something like 10 inches. This mains the blue line block needs to travel 60 inches inside the mast. Either that or you need to pretension the setup but repositioning the slip knot in the green line. My setup is just a little too short to go from fully slapck to fully tensioned and so I use this slip knot trick to preset the tension or the conditions I'm expecting. I can even do that easily on the water and have.

Wouter

The way I rigged the downhaul on my Mattia 18HT


I think the advantage of my setup was, that it was easy to install and to get the right lenght of the lines.

But I must admid, that the setup of the Typhoon F16 looks allot cleaner.