Mast Rake

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Sep 3, 2007
1
- - Boise, ID
I am ready to purchase a new main sail for my Hunter 34. I noticed the mast has a rake or curve to it. I would like to know if the mast was made that way originally or if it is due to tension in the back stay. Thanks
 
R

Rick9619

Some masts (B and R rigs) do come with slight prebend, but since yours has an adjustable back stay, it sounds like an "older" model 34. The "rake" is due to your backstay tension. If you have the specs for your mainsail, then that is what you should order if you want a "stock" sail. You can also find the spec on this site. Also, I would recommend a few bucks to have your rig tuned if you are not familiar with doing it yourself. Definately worth it. Cheers
 
K

Ken

Rake & prebend

Rake is the backward angle of mast. Prebend is the curve induced by the rigging at near mid section of mast. Each serve different purpose.
 
Jun 3, 2004
890
Hunter 34 Toronto, Ontario Canada
As Ken says

rake and prebend are 2 different things. Prebend ( on a B&R rig) is induced by tightening the spreader tip to mast shrouds ( they have a name but it escapes me) when the mast is off the boat. The specs say a 5" bend for the H34. Rake is the tilt (backwards) frtom vertical. If you have a backstay adjuster you can induce rake on your prebent mast (and tighten your forestay) A good sail maker should recognize the prebend characteristics of the B&R rig
 
C

Craig

How Much Rake?

I get the prebend...how much rake should you have on a 34?...has anyone used a line off the back of the mast with a weight to measure this?..thanks
 
Oct 14, 2005
2,191
1983 Hunter H34 North East, MD
Craig...

When I set up the masts on smaller boats as a dealer, Hunter's rake instruction was to hang a weight on the main halyard and rake the mast back to where the weight hung six inches behind the mast at the boom level. I haven't seen a similar spec for the '83-87 H34's with the B&R rig. There is a special concern for those H34's like mine fitted with the Hyde furler system that putting too much backstay tension on the rig could lead to connective failure of one of the furler foil fittigs, given the age of these systems. As the furler foil is actually the headstay itself, this is a major consideration when tuning this rig. I have not been able to document such a failure as yet to validate this concern.
 
Dec 2, 1999
15,184
Hunter Vision-36 Rio Vista, CA.
check out the manual for the proper pre-bend

Randy: Be sure to check out the resources tab for the manual on the B&R Rigs for your model. If you have an 83-87 H'34 you will see how the pre-bend is designed to be put in before the mast is stepped on the boat. You definetly want a sailmaker that know what the hell they are doing before you spend a couple of thousand on a new sail. You best bet may to purchase one from the HOW site!
 
Jan 22, 2008
193
Hunter 34 Seabeck WA
What Dan said is scary.

I've not heard of a foil or furling system that replaces the headstay. The headstay on a H34, and most B&R rigs, is the only thing holding the mast UP. When it fails, mast go bang. (on your deck) It pays to be aware of the symptoms of headstay degradation and subsequent failure. Because the headstay can't be seen inside the foil, the only symptom of doom is the foil will not rotate easily when broken strands of wire interfere with the foil operation. Did I say scary? I also keep a spare halyard forward on the pulpit as backup. If the mast tries to come down I suspect that the pulpit will just come with it but at least a second or two will be gained in order to DUCK! Now, that said, I've never heard of a H34 mast failure as above. I think the foil protects the headstay from corrosion. At least mine looked great after 15 years. The shrouds were shot two years before that inspection. But a foil system that replaces the headstay? Not on my boat!
 
E

Ed

mainsail

bought a new main for my 34 last fall. My sailmaker wanted the amount of mast bend so that he could build the sail to suit the mast shape. I hoisted a ruler up the mast to get a measurement from the mast to a line stretched from the masthead to the boom fitting.
 
Oct 14, 2005
2,191
1983 Hunter H34 North East, MD
Fred...

There was a discussion on another list a couple of years ago about replacing the bearings in the rotating end-points when the furler rotation stiffens. This may be the only course of action that can be taken with this system short of a complete replacement. The "foil" is not an extrusion that rides over the headstay wire but a solid metal extrusion that IS the headstay, as in rod rigging. I do get scared in a pitching seaway when the mast starts pumping, making an immediate course change a necessity for one's sanity.
 

Alan

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Jun 2, 2004
4,174
Hunter 35.5 LI, NY
Dan

Mast pumping is an indication of a rig that is too loose. Check the tension on your shrouds and maximize their readings. Increasing backstay tension will minimize mast pumping also. I agree with Fred's assessment. A furling extrusion that IS your headstay is a failure waiting to happen. Unfortunately this will take the whole rig down when it fails. Dan, I can understand the fear you must feel with the uncertainty of the integrity of your rig. I would bite the bullet and replace the system before its too late.
 
D

Dan Johnson

Alan...

after I noticed the pumping occurring when I first bought the boat, I had my rigger make the necessary tension adjustments on the rig to bring it into spec. I do race, but not this boat, so I was immediately aware of the problem and the cure. The boat is used for weekend cruising. I took down the 150 genny that was on the boat when I bought it and rehung the original 110. It is a much better performer with the original sail area, even in the light air of summer. The 150 is just too much headsail for this boat in anything more than single digit air speeds. The bullet to be bitten has a price tag of over $2K. I would be much more inclined to pull the trigger if I could find documentation of this furler failing. Until I do I will continue to keep the rig in tune with the minimal application of backstay tension (enough to keep the wrinkles out of the jib luff).
 

VINN

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Aug 23, 2005
84
HUNTER H34 point lookout long island
rig tension

my elbow slipped off the arm chair reading some of these responses. i suppose the worst can happen to someone. there are allot of those h34 around all over north america. maybe 1100 or so. i have a harken furler that looks pretty sturdy. are they safer than the hyde system? my foil looks like a 2 peice job, and is not perfectly straight after all these years resting on top of the boat during the hard winters. i have a real good rigger that sets mine up every year, and i just do minor tuning to keep it safe. ive seen him do everything from j145 to dingys, so i can trust his work. he sets my rig up just firm, and never warned me about any dangers. if you can play your shrouds like a high guitar string, there way too tight! ive seen rod rigging that tight on j boats, but thats an entirely different animal. for a coastal cruiser that was designed to handle lighter demands, and stresses from a crew, should have the rig tensioned for alittle give, to protect all the hardware on board. chain plate, and deck presures will rise too high, and may deform the hull with a rig thats too tight. and by the way some h34 have compression post problems, another reason to keep rig presures down to normal. mine looks ok after all these years so why push my luck. forestay sag is acceptable with a firm backstay setting in winds 12 knots or less. i downsized to a 125 last summer for the same reason, to reduce sag up front, and reduce high sheet loads on those little winches, and my arms that are just getting over tennis elbows. have you guys ever had that from flying a 150? dropping from 745 sq ft to 650 should give all the rig attachment points a rest after all these years, including all your own joints too.
 
Oct 14, 2005
2,191
1983 Hunter H34 North East, MD
Vinn...

I believe Hyde was the only furler system that forms the headstay itself. The others (Profurl, Harken, Schaffer, etc.) all use aluminum extrusion "foils" that ride over the wire headstay to carry the headsail. On smaller boats, CDI takes your headstay and modifies it to fit their furler system. You sound like you're in good hands and should have no problem. The key is adequate tension, not violin string tight.
 

VINN

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Aug 23, 2005
84
HUNTER H34 point lookout long island
DAN

thanx for the info dan, it was a great relief. besides sinking, demasting a rig ranks near the top of the worsts things that could happen to a sailboat owner. ive had mine in the water all winter, sailing in the ocean off long island. its a very very lonely place out there now. at least now, i have a piece of mind.
 
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