H336 forestay adjustment - mast rake -B&R

[curtdo]

I recently measured the prebend and rake in my 336 mast. Per some other posts on this board, I think the mast is way off. The prebend seems to be about 6", which is not too bad....however the rake is about 24".

I proceeded to loosen all the shrouds and then started tightening down the forestay (which has furlex installed). The rake of the mast hardly moved. So I eventually took the nut on the forestay adjustment as far down as it would go. It moved down about 3". I tightened back the shrouds as needed to get proper tension with loos gauge.

The result...I only moved the rake forward about 3".

What to do???? Any suggestions would be welcome.

 

[HernandoBeacher]

You might want tho review the Selden Tuning Guide available on their website.

 

[Don12364]

Is your boat heavily loaded down at the stern? I check mine with nobody in the cockpit and with a full bow water tank (75 gals US = 620 lbs) and an empty grey water tank.

If your measurements are right I would expect you to have a boom that appears to be sagging and the boat to be very hard mouthed to sail upwind.

 

[Ken13559]

When 1st got my boat, the yard fitted the short attachment for the Furlex. Mast rack was 24". Later I hot them to shorten the forestay and fitted the longer Fulex attachment. That gives more adjustment to tighten the forestay thus mast rack is now 12".

 

[curtdo]

Thanks guys.

I did follow Selden tuning guide, but it doesn't address my problem

As far as water tank...it was not totally full, I will fill and recheck. And, yes the boat has been difficult to control upwind, with heavy weather helm, but I did not notice boom sag.

I hope I don't have the wrong forestay length, but that may be the case.

 

[Ken13559]

If you have the forestay cutting sheet, you can recut it but replace the short attachment with longer one. Long one should be extended, then you will have enough adjustment. Too much rack gives you weather helm.

 

[harv]

I recently measured the prebend and rake in my 336 mast. Per some other posts on this board, I think the mast is way off. The prebend seems to be about 6", which is not too bad....however the rake is about 24".

I proceeded to loosen all the shrouds and then started tightening down the forestay (which has furlex installed). The rake of the mast hardly moved. So I eventually took the nut on the forestay adjustment as far down as it would go. It moved down about 3". I tightened back the shrouds as needed to get proper tension with loos gauge.

The result...I only moved the rake forward about 3".

What to do???? Any suggestions would be welcome.

Per Hunter just a few days ago-for a H310 swept back rig-no backstays:
"The rake is going to land somewhere around 10". According the gear it can go either way a couple of inches. Sometimes it's more about how it sails rather than the settings."

The H310 has a 37Ft mast. You can adjust your rake accordingly.
Re: "sails"-The larger the rake the more helm pressure you will have.

 

[Ken13559]

There is only so much you can do with adjusting the forestay tang buckle, after that you have to shorten the forestay. Correct mast rake reduces weatherhelm.