lengthening forestay

On my 1986 h18 magnum , is the mast raked back too far if I am using the original forestay hardware that came with the boat when it was new? It is pinned at the very bottom of the chainplate adjuster. Is this too much rake? If so, can anyone suggest a way to measure it to get it to the best angle???

Dang! I forget the measurement....SRM, do you remember?

Take a tape measure and a marking pen/pencil.
Measure 48" up from the base of the mast, and make a mark on the front of the mast.
Now measure from that mark to the bow tangs.
I think (from memory, someone help me remember please!) it should be 73".

Try a search on this Forum.

H18's don't use as much rake as H16's.
Once you 'set' the rake, leave it there.

Good luck.

_________________
2015 H16, with spin,
SOLD 1989 Hobie SX18 Sail # 1947 "In Theory..."
'Only two things are infinite, the universe, and human stupidity. But I'm not sure about the former.'

Found it.

From the 48" mark, set the rake so that the measurement from that mark to the bow tangs are between 103" and 107".
On my old H18SX, we were at 104 1/2".

cheers

_________________
2015 H16, with spin,
SOLD 1989 Hobie SX18 Sail # 1947 "In Theory..."
'Only two things are infinite, the universe, and human stupidity. But I'm not sure about the former.'

That's it. I hear the Australians, who still race the 18 competitively, have raked their masts back even further. I haven't measured mine in a while, but I've got quite a bit of aft rake. My forestay chainplate is pinned 2 holes up from the bottom, and the shrouds get pinned about 4 holes up from the bottom on the 10-hole shroud adjusters. When sheeted in fully, my mainsheet blocks are about 6" apart.

A note about the rigging... Hopefully when you mention "forestay hardware," you're referring just to the adjusters & chainplates. 36 years old is dangerously old for rigging, I'd replace that asap! The adjusters & chainplates are probably fine, though you ought to inspect them for significant damage. You may want to replace the twist toggles if they show any signs of fatigue, and definitely should replace the shroud anchor bolts if those haven't been replaced... they have a reputation for failing without warning.

_________________
Mike

'79 H18 standard 'Rocketman II' sail #14921 RIP
'78 H18 (unnamed) sail #14921
'08 H16 sail #114312
'97 H21SC sail #238

Guys, Thanks for the info and I will take a close look at my rigging as you suggest DJ

DJ, sounds great! However, I've only just realized that my rigging has been wrong for years... I have been trying to figure out why I couldn't find a "proper" Hobie 18 forestay to replace my old one... turns out someone put an extra swivel at the top of my forestay, so don't go by the hole positions I stated. I'm guessing once I remove the extra swivel, I'll have to pin at the bottom-most hole on the forestay adjuster to get the same amount of mast rake that I had previously.

My forestay was rigged such that I had the upper forestay with swivel connected to the jib halyard sheave, connected to another swivel, connected to the forestay. This often caused frustration when rigging, in that I'd try to pull out the jib furler but end up twisting the jib halyard around the forestay... now I know why!

Googling online, it seems that either a) early Hobie 18's had two swivels on the forestay, and my forestay is WAYYYY older than I thought, or b) someone rigged it that way intentionally, but it seems unlikely... my forestay has two fork ends, and every replacement that I've been able to find only has one. When I went to buy another forestay and noticed it was rigged the same way, I reexamined the parts guide and noticed that it shows the forestay that I bought is correct, and the "lower swivel" is not. And here I thought I knew all there was to know about my boat!

A note about mast rake - it will cause more weather helm on your rudders by moving the center of effort of the sails aft. Raking the mast forward more will reduce weather helm, but it will also reduce your pointing ability somewhat.

_________________
Mike

'79 H18 standard 'Rocketman II' sail #14921 RIP
'78 H18 (unnamed) sail #14921
'08 H16 sail #114312
'97 H21SC sail #238

Hi guys and gals, I am the Aussie who runs LOTS of mast rake and it works - like a rocket ship. My rake measurement can he found on my boats own Facebook page in the footer link below. I run a set and forget system. No chain plate adjuster. Just one correct length forestay and go sailing. Feel free to ask me any questions via FB messenger. Note: there are various photo albums on the FB page so u need to find the correct album.

_________________
John Forbes
Hobie 18 Reimagined
Sail # 490
Boat name: 18@heart
http://www.hobie18.fun
https://www.facebook.com/Hobie18catamaran/