I would like to add a bowsprit to my hunter340. Any assistance will be greatly appreciated. I have looked at a trogear as well as a selden. Also will I have to add bob stay. Thanks
Bow sprit add on
- Thread starter HD74
- Start date
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,440
Well break out 1.5 to 2.5 boat bucks for the hardware. Than another if the yard is going to install. I figure the job is a two plus day install and at least a bottle of 15 year rum.
If the forestay is going to be moved to the end of the bowsprit, yes you will need a bobstay to distribute the load to the hull and counter act the headstay forces. Doing this will significantly alter the rig's geometry, so talking to a good qualified rigger would be important.
If the bow sprit is simple to move the anchor forward a bit to add an anchor roller and/or for cosmetic reasons, then a bobstay is probably not needed. Depends on the size of the bowsprit and its intended use and the forces that will be applied to the forestay.
I’ve had a bowsprit on my 340 for several years. It gets a lot of hard use when we’re racing, never installed a bob stay. It’s right at three feet past the anchor roller.
"No Drill" Bowsprit
Lots of video on the boat’s YouTube channel of the bowsprit in use.
Think of the bow sprit as a lever with the pivot point at the bow. The forestay or the A-sym halyard applies and upwards force that must be counteracted by a downward force. In your case the downward force is applied to the hull through the bar passing beneath the foredeck cleats with the pivot point somewhere around the stem. The key is the aft end of the pole is sufficiently far aft to counteract the forestay/halyard forces, so a bobstay is not necessary. The pole is cantilevered.
In traditional bow sprits, the bow sprit does not go back far enough to obtain a sufficient cantilever, so the bobstay transmits the force to the hull. In this case the bowsprit is more like a spreader, the forces it transmits are in compression.
Whether a bobstay is necessary really depends on the design and intended use.
The post was for a Hunter 340, I would be surprised if they want to use the bowsprit for anything other than an a-sail or reacher tack mount. Also mentioned Selden and Trogear. I have never seen a Selden bowsprit with a bobstay, but I’m sure someone has. And a Trogear requires an adjustable bobstay. On my Hunter 340, a bobstay has not been necessary with the length of bowsprit I have and flying a code 3 asymmetrical with the halyard just above the forestay. I would not recommend putting the halyard at the masthead and getting an oversized a-sail with no backstay on a Hunter 340. If you are thinking about installing a reacher on a top down furler, you might consider a bowsprit with a bobstay to keep the luff tight.
The Selden offering does not require a stay, and in fact, that may just get in the way. I heard a lot of doom and gloom about using the anchor hatch as a rear attachment point - how the pole work rip the hatch off and a great gaping hole would open up the lake and we'd all wind up in Australia. There's very little interaction at the rear of the pole, beyond general housekeeping. The vast majority of the loads and forces are, as Selden suggests, at the ring.
The force on the aft end of the pole is down, not up. If the anchor hatch is weak the pole might crack it and cause it to collapse, but it won't lift the hatch unless maybe you go shrimping with the chute. Now if the pole is used to secure the anchor and move the rode away from the boat, the anchor hatch might just launch itself, but not all the way to Australia.
Correct. The kite pulls the pole up and the ring acts as a fulcrum. Oddly enough, there isnt that much force on the aft end.
I have two rubber feet on the aft end, and the pole tends to sit to one or the other, when on the Wichard cleat. If you lean on the aft end, both feet will be on the deck. Ive never seen the sail push it down that hard.
Your experience might differ, but since i made this from scratch, i tend to watch it very, very closely.
I have two rubber feet on the aft end, and the pole tends to sit to one or the other, when on the Wichard cleat. If you lean on the aft end, both feet will be on the deck. Ive never seen the sail push it down that hard.
Your experience might differ, but since i made this from scratch, i tend to watch it very, very closely.
Thanks Bill I was looking thru your pics great! At the aft end of sprit that must be a custom mount, If so would love to get the material and installation instruction. What length is the sprit.
The whole thing is custom I guess. I originally made it from 2" aluminum conduit and that bent, pretty easily. I got a piece of 3" aircraft aluminum from speedymetals.com. the longest piece you could get without paying extra shipping, 5 feet. So that's how I picked that length. The cross piece is 1/2" stainless steel pipe I got out of the junk bin at work, pipe not tubing. It centers it and keeps it from getting pulled out of the boat from the front. The plastic ends I found laying in a parking lot. I double stacked two rubber bumpers under the pipe where it presses on the anchor locker lid. A line comes out of the bottom at the anchor roller and comes back to the turning block and to the cleat to hold it down. Probably way under a couple hundred bucks into it.
Only thing I don't like about, you have to remove it to use the anchor. You can see the 2013 registration sticker in the photo, so it's held up real well.
Here is alink to a post on a guy that made an aluminum version of the Trogear style sprit. The pictures begin at post #73 and a complete bill of materials with cost is in #80.
homemade Trogear
homemade Trogear