Catsailor.com Mid boom sheeting, interesting photo
Posted By: Robi Mid boom sheeting, interesting photo - 08/07/06 02:59 PM
Got this from the link posted to the A cat worlds. Correct me if I am wrong, but this is Glenn Ashby?
![[Linked Image]](http://www.opengate.se/media/repos/vastervik/a_cat_wm/Content/images/acatwc_112_han_som_leder_efter_race2_med_tva_forstaplatser.jpg)
Is this what is involved with mid boom sheeting? I like this setup very much. Seems like a 8:1 in the rear to a block, to a ratchet block on the tramp.
Also seems like he has his outhaul at mid boom as well?
Posted By: Robi Re: Mid boom sheeting, interesting photo - 08/07/06 03:05 PM
Here is another photos
![[Linked Image]](http://www.opengate.se/media/repos/vastervik/a_cat_wm/Content/images/acatwc_130.jpg)
Posted By: Mark P Re: Mid boom sheeting, interesting photo - 08/07/06 04:29 PM
My friends Auz Flyer uses this system to good effect. However , It could cause hassle with our spi halyard and sheets and I'm not convinced my tramp would take the strain as their mains are over 2m smaller than ours. If anybody suffers from back problems this would certainly stop the twisting effect of our rear sheeting, and if someone does convert or is already using this system then I'm sure we would be interested in the results.
Posted By: Timbo Re: Mid boom sheeting, interesting photo - 08/07/06 04:37 PM
I was thinking about this the other day, what if you just put a block on the boom, like he has for the out haul, only the next larger size, instead of running the mainsheet all the way down to the tramp? I know the boom would have to be beefy enough to handle the load there but it might be stronger than the tramp, and that would keep the mainsheet up out of the way of the spinaker stuff on the tramp. Has anyone seen it done like that?
In that first picture you can see he has a larger ratchet block on the tramp but it has no clete with it, why not just run that right off the boom instead of the tramp?
Posted By: Eric Anderson Re: Mid boom sheeting, interesting photo - 08/07/06 06:36 PM
Tim,
What you are describing is implemented on A cats regularly,
Ronstan makes a block that works well for this puropse.
Part #
RF 62175 low lead ratchet with cam
Alternatively you can buy it witout a cam.
These blocks have awesome holding power much better then the harken ones, but they do chew up line quickly so you will need to replace your mainsheet more often
Cheers
Eric Anderson
Posted By: Timbo Re: Mid boom sheeting, interesting photo - 08/07/06 07:05 PM
Thanks Eric, has anyone tried it yet? I recall Wouter had put up some info about a 2-1 mainsheet on the boom some time back, I could see where you could rig it for use either way just by changing where you tie it off. Any F18's using that?
Posted By: pdwarren Re: Mid boom sheeting, interesting photo - 08/07/06 07:16 PM
It strikes me that the disadvantage of putting it on the tramp is that it doesn't leave much room for the crew when you tack, if you're sailing two-up. On the other hand, it gives the crew a better sheeting angle if they're doing the main.
Paul
Posted By: ejpoulsen Re: Mid boom sheeting, interesting photo - 08/07/06 07:28 PM
Thanks Eric, has anyone tried it yet? I recall Wouter had put up some info about a 2-1 mainsheet on the boom some time back, I could see where you could rig it for use either way just by changing where you tie it off. Any F18's using that?
Paul (#300) has used center sheeting for some time. The difference between he and Ashby is that Paul uses a cleat (look at the Photo of Glenn--no cleat). Photo attached of Paul--blow up photo to see mainsheet set up. Note that his boom is larger in diameter than the standard Taipan boom. I've sailed on Paul's boat and didn't find the setup helpful for me. He likes it because he used to sail a Musto Skiff.
Glenn sent me a parts list needed to set up your sheet like his and I could dig it up if someone is interested.
Posted By: Robi Re: Mid boom sheeting, interesting photo - 08/07/06 07:56 PM
Glenn sent me a parts list needed to set up your sheet like his and I could dig it up if someone is interested.
<img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" /> <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" /> <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />
Ill be waiting patiently.
Posted By: ejpoulsen Re: Mid boom sheeting, interesting photo - 08/07/06 08:39 PM
Glenn sent me a parts list needed to set up your sheet like his and I could dig it up if someone is interested.
<img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" /> <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" /> <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />
Ill be waiting patiently.
Robi,
I sent it to your regular email address.
Posted By: Timbo Re: Mid boom sheeting, interesting photo - 08/07/06 08:48 PM
Either way, you still have to get the hiking stick around the back of the blocks (traveler)on every tack, that's the part I don't like. If we could figure out a way to just cross under the boom while looking forward and not have to go to the back of the boat, that would be great!
Posted By: Robi Re: Mid boom sheeting, interesting photo - 08/07/06 08:54 PM
But Tim, going to the back of the boat, actually helps you with the tack.
Posted By: Berny Re: Mid boom sheeting, interesting photo - 08/07/06 11:31 PM
I think Glen's system there is 8:1 i.e., 7:1 at the rear and the lead forward I think qualifies as another purchase. I also think he has a wire under the tramp to take the block loading.
I'd like to know how those straps/strops are attached to the boom. Probably epoxy. Definitely NOT drilled and riveted I'll bet. <img src="http://www.catsailor.com/forums/images/graemlins/smirk.gif" alt="" />
I asked about this system and sheeting directly from the boom in and earlier post but got no satisfactory answers <img src="http://www.catsailor.com/forums/images/graemlins/frown.gif" alt="" /> but I think it would work. I can't see any more load on the boom doing it that way than there already is. I doubt I'd use the system now though because of the kite sheet and halyard presence on the trampoline. Too congested.
Don't you just love 'A's. I hope I get to own one before I die.
Bern
Posted By: Timbo Re: Mid boom sheeting, interesting photo - 08/07/06 11:49 PM
Berny, sneak around at an A cat regatta, when they come in get them drunk and take one for a ride!
Posted By: ejpoulsen Re: Mid boom sheeting, interesting photo - 08/08/06 12:32 AM
Berny, Here's the email he sent me--sounds like there is no wire and just rivets.
Hi Eric,
hope you had a good Easter and a good sail with the new rag...
...The centersheeting could be a tricky one but I will try and explain.
I think it is better to sail with centre sheeting as I have grown up sailing dinghys like Lasers and optimists so prefer the mainsheet to come fro the middle of the boat.
I think it is also better for my back to pull the mainsheet straight up the line of my body and not across like you have to do with the rear sheeting.
The Blocks you will need to have it the same as mine is
2 RF40101 (Single Blocks) One of these gets attached to the middle of the boom. Your boom must be at least 40mm Alloy or strong carbon. Use webbing and rivets for the boom.
1 RF40312 (Triple Block with becket) This block goes on the traveller car and has the end of the mainsheet attached to it.
1 RF40302 (Triple Block) Attach one of the single blocks to this and this attaches to the sail and boom.
1 RF1720 ( Ratchet Block for the tramp)
The Trampoline will need to have some heavy sailcloth reinforcing where the Ratchet block goes. Usually 3 layers of heave cruising cloth will be good. (your sailmaker will know) Use a saddle to attach the block there with 2 nuts and bolts and put Large washers under the nuts so they dont pull through the cloth.
It takes a while to get used to using the new system but i think it is worth it. See how you go!!
Regards Glenn.
Posted By: Anonymous
Re: Mid boom sheeting, interesting photo - 08/08/06 02:06 AM
From the Capricorn owners manual (
www.ahpc.com.au). A great solution if your crew sheets main for you.
![[Linked Image]](http://xs104.xs.to/xs104/06322/amain.jpg)
Posted By: Anonymous
Re: Mid boom sheeting, interesting photo - 08/08/06 12:29 PM
Hi all,
"Altered" has always had mid boom sheeting, I carried it in from my Mosquito's and the A that "Altered" came from. By the way the first Mossie I had was sloop rigged with mid boom sheeting and was OK. Mossie has less tramp space than a F16. <img src="http://www.catsailor.com/forums/images/graemlins/tongue.gif" alt="" />
My boom is a carbon sailboard mast top section. Is smaller in diameter than most A booms and doesn't bend or break. Currently my boom hangers are Kevlar rope with the ends teased out and epoxied on. Previously I used seat belt webbing wrapped around with one rivet to stop it slipping, but the rivet still got loose, epoxied on is best.
I use a swivelling cleat RF7, initialy this was mounted on tramp alone with a Large thin aluminium plate underneath this worked OK, but after some changes I put a pole up centre of my tramp and cleat is now fixed to it. In both instances it is very important to get cleat angle right. I find I need to cleat regularly to rest arms for downwind work with spin.
Mossie Tim has sheet dropping straight from middle of boom, many skiffs do it this way. But when I sail his boat I get tangled in it. Like so many things in set ups no right or wrong just what you are used to.
I will try to take a photo this weekend.
Regards Gary. <img src="http://www.catsailor.com/forums/images/graemlins/cool.gif" alt="" />
Posted By: C2 Mike Re: Mid boom sheeting, interesting photo - 08/08/06 11:16 PM
My friends Auz Flyer uses this system to good effect. However , It could cause hassle with our spi halyard and sheets and I'm not convinced my tramp would take the strain as their mains are over 2m smaller than ours. If anybody suffers from back problems this would certainly stop the twisting effect of our rear sheeting, and if someone does convert or is already using this system then I'm sure we would be interested in the results.
Goodall runs a very similar system on his personal Capricorns. IMHO it is not worth the effort but the normal rear beam system is what I'm used to. There is a slightly better sheeting angle if the crew takes the main however I find it more difficult to control the sheet during a tack/gybe.
Tiger Mike
Posted By: Anonymous
Re: Mid boom sheeting, interesting photo - 08/09/06 01:07 AM
I would have thought it would let you tack without handing the sheet backwards and fwds between the crew and skipper.
Posted By: Wouter Re: Mid boom sheeting, interesting photo - 08/09/06 12:11 PM
It is still in planning phase on my side. I'm looking at having a block at 40 % of the boom as others describe. However, I'm out of (boat) money for the moment so it'll probably by next season at the earliest. By the way, the A-cat setup will be in the way of doublehanded sailing and not having a cleat is bad news for spinnaker sailing. Personally I'm finding that the rear setup is pretty acceptable when singlehanding and that the boom setup has other downsides when doublehanding which makes application less appealing that on the A-cat. Alsp the way I run my spi lines will directly conflict with any trampoline based mainsheet block.
An A-cat sailor once told me that when the switched from rear sheeting to centre sheeting that doing the wildthing on downwind legs was much improved. Sadly on an F16 this is not an important consideration as the addition of the spinnaker makes the F16 behave totally different on the downwind leg. Doing the wildthing is almost near done on a F16.
The two boats are really diverging both in design and the fitting out. The addition of the spinnaker really does change the total concept of the boat.
Wouter
Posted By: C2 Mike Re: Mid boom sheeting, interesting photo - 08/09/06 09:52 PM
I would have thought it would let you tack without handing the sheet backwards and fwds between the crew and skipper.
Yes it does. However I trim the main 75% of the time with the crew only taking it when the dh is maxed out. For me, the main running from the rear beam works fine and I see no advantage to change
Cheers,
Tiger Mike
Posted By: warbird Re: Mid boom sheeting, interesting photo - 08/10/06 06:30 AM
I have found the problem with rear sheeting on a one sail, one man boat that when you are sheeting hard while on the wind the effort pulls your weight back on the boat. Exactly what you do not want. Now, if you have a cleat this might be lessened but CA seems to prefer no cleat so maybe he just wants his weight balanced when pumping the sheet. woosy booms used for rear sheeting must be strengthened for mid sheeting or it's goodnight nurse.
Posted By: Berny Re: Mid boom sheeting, interesting photo - 08/10/06 07:53 AM
I don't think you can use a block with cleat on the tramp. The cleating angle changes as the traveller is eased making it difficult to cleat and release. I tried a swivel cleat with alum disc under the tramp for my spanner and it was a big fizzer for that reason.
Posted By: Wouter Re: Mid boom sheeting, interesting photo - 08/10/06 10:37 AM
My crew handles in the mainsheet as soon as we have one on the wire. But we still hand the sheet over when tacking. I think this to be the better method no matter how the sheet is run. During the tack the crew often does some smaller trimming/tuning or tries to get to the trapeze quickly. Either way he or she is not helped in those activities by having to also handle the mainsheet. On my boat I find I need to improve my tacking by careful sheeting. This will require to much close coordination if the crew was doing that for the skipper. So personally, I fully expect to keep handing over the sheet before and after tacks not matter what sheet setup.
Wouter
Posted By: Wouter Re: Mid boom sheeting, interesting photo - 08/10/06 10:43 AM
but CA seems to prefer no cleat
That is typical of the A-cats. They have only have one sail to trim and sheet and so can get away with a cleatless mainsheet. It actually forces them to not fall away in a set and forget attitude which is slow on an A-cat. Especially on downwinds.
Other designs however have a strong need for a mainsheet cleat especially the single handed spinnaker boats.
Personally I lean forward a little against the pull of the rear sheeted mainsheet and that feels alright to me. When doublehanding I'm using higher sheet loads and really in that setup I can't hold the sheet for long periods unless I use both hands or the cleat. I'm not sure about the next statement but could it be that doublehanded sheet loads are significantly higher ? It sure feels that way to me.
Wouter
Posted By: ejpoulsen Re: Mid boom sheeting, interesting photo - 08/10/06 03:32 PM
I don't think you can use a block with cleat on the tramp. The cleating angle changes as the traveller is eased making it difficult to cleat and release. I tried a swivel cleat with alum disc under the tramp for my spanner and it was a big fizzer for that reason.
I've seen it done successfully mounted on the tramp with a cut-in-half tennis ball with the cleat attached through the middle. Ball pads the cleat and holds it upright as it swivels back and forth.
Posted By: warbird Re: Mid boom sheeting, interesting photo - 08/10/06 09:28 PM
Personally I find a cleat invaliable for careful trim of other controls with a limited use attitude.... but I am not winning a lot of regattas. : )
When I am in heavy weather and pumpng the main (I do not like to use the traveller up wind) I can only pull in as hard as I can..doesn't matter what the loads are.
One of my favourite boom sheeting arrangements is on the Windrush 14. The mains blocks exit up to a rachet on the boom only 18 inches from the rear attachment point. The business end of the main is always hanging waiting if you have lost it and it is easy to get around and sheet never dogknots. I believe Ronstan now make a swivelling cleat for exactly this style.
Having said these things I am very clear that different trim set ups work for different people and that less fidgeting makes for more speed.
Posted By: ncik Re: Mid boom sheeting, interesting photo - 08/10/06 10:45 PM
Are there any particular conditions when ppl set/cleat the mainsheet and play the traveller instead?
Posted By: Mark P Re: Mid boom sheeting, interesting photo - 08/11/06 07:22 AM
The only time I have cleated the Main and played the traveller was on a long windy wavevy reach. So windy that the traveller stayed alot closer to the leeward hull than centre of the beam and only about 15% of the Main was in use. I was struggling and scared but managed to keep infront of an Inter 20 for the 2km duration. However, on the next bear away at the Windward mark the bows went down the mine and I was soon doing my impression of Superman flying past the hounds, by the time I surfaced the boat had drifted away from me so I ended up swimming back to the Windward mark. In the meantime the rescue boat was frantically carrying out a search for me 200m or so down the run.(Funny how you remember certain races)
Posted By: ncik Re: Mid boom sheeting, interesting photo - 08/11/06 07:40 AM
hhahaa, doh! Sounds like a "fun" day...
Posted By: Berny Re: Mid boom sheeting, interesting photo - 08/11/06 10:00 AM
I remember a time ocean sailing on a delivery when we had problems with the rudder which seemed to have lost much of it's ability to steer and I used the traveller to assist with steering. We had a reef in with plenty of breeze and it worked well for a few hours till we put into a port. Turned out we had lost part of the rudder blade after hitting something.(Funny how you remember certain voyages).
Posted By: Wouter Re: Mid boom sheeting, interesting photo - 08/11/06 10:38 AM
I typically use the maintraveller under spinnaker sailing. I simultaniously sheet out when I try to bear down and visa versa. On my boat this really helps the boat down quickly under spinnaker without much heeling or loss of speed. Typically I do this is gusty and shifty winds of some strength.
Wouter
Posted By: _flatlander_ Re: Mid boom sheeting, interesting photo - 08/11/06 03:03 PM
My crew handles in the mainsheet as soon as we have one on the wire.
Wouter
And who, at this point, "handles" the downhaul?
Posted By: Rolf_Nilsen
Re: Mid boom sheeting, interesting photo - 08/11/06 03:47 PM
Skipper, or set it and concentrate on driving the boat.
Posted By: _flatlander_ Re: Mid boom sheeting, interesting photo - 08/11/06 08:31 PM
Skipper, or set it and concentrate on driving the boat.
AHA!! This is starting to make sense. Newbies to the H20, we're being told to use the downhaul in puffs. I can't break my "habit" of driving a boat through the puffs. I also don't feel comfortable with leaving it entirely up to the crew to bring the hull back down, via downhaul, consequently we'll have moments of simealtaneous adjustments (tiller & downhaul) resulting in tea bagging. I think I can easily incorporate working the downhaul and driving.
My apologies (we're aspiring F16 sailors), sorry for offering nothing to the mid-boom conversation and thanks again.
Posted By: Wouter Re: Mid boom sheeting, interesting photo - 08/12/06 06:59 AM
I don not handle the downhaul very often, but mostly in this configuration it is the skipper.
Wouter
Posted By: Tim_Mozzie Re: Mid boom sheeting, interesting photo - 08/25/06 04:50 AM
Here's the long awaited photos Gary mentioned.
This is Mosquito mid-boom sheeting straight from the boom.
![[Linked Image]](http://www.catsailor.com/bb_files/84099-sfs_2006_0812AB.JPG)
And here's a closer look at the cleat. Only used when the spinnaker is up, and only cleats when I pull straight back along the boom.
![[Linked Image]](http://www.catsailor.com/bb_files/84100-sfs_2006_0812AC.JPG)
This is F16 Altered's mid boom sheeting system, with a Ronstan swivel (RF7 320g) mounted on a centre beam.
![[Linked Image]](http://www.catsailor.com/bb_files/84101-sfs_2006_0812AE.JPG)
Posted By: Tim_Mozzie Re: Mid boom sheeting, interesting photo - 08/25/06 04:52 AM
Photo holding post.
Posted By: Tim_Mozzie Re: Mid boom sheeting, interesting photo - 08/25/06 04:56 AM
Photo holding post 2.
Posted By: Tim_Mozzie Re: Mid boom sheeting, interesting photo - 08/25/06 05:06 AM
And here is the Mozzie centre sheeting in action at the Brass Monkey Regatta (you can wonder why the regatta has this name - it is winter but...).
The best thing about sheeting this way is you never have to look for the sheet on the tramp. It's always hanging in front of you.
![[Linked Image]](http://www.inspiredgraphix.com.au/sfsbrassmonkey/images/Brassmonkey226.jpg)
Brass Monkey 2006 - Photo site Posted By: warbird Re: Mid boom sheeting, interesting photo - 08/25/06 06:22 AM
On Altered what is the sheet below the main swivel/clam cleat?
Posted By: scooby_simon Re: Mid boom sheeting, interesting photo - 08/25/06 06:52 PM
On Altered what is the sheet below the main swivel/clam cleat?
Spi up or down at a guess.
Posted By: Anonymous
Re: Mid boom sheeting, interesting photo - 08/26/06 07:19 AM
if you mean the rope going through the cleat at the base of the swivelling mainsheet cleat, it is the spinnaker halyard-retrieval line.
The things I like about this system for one up sailing are.
Mainsheet is always in front of you.
Easy cleating, uncleating from anywhere on the boat tramp or trapeze.
It keeps the spinnaker sheet back where it is easily grabbed.
Mounting the spin halyard cleat at the base of the main cleat keeps it close to hand, making cleating and uncleating easy from the back of the tramp.
Regards Gary. <img src="http://www.catsailor.com/forums/images/graemlins/cool.gif" alt="" />
Posted By: warbird Re: Mid boom sheeting, interesting photo - 08/27/06 07:26 AM
Thanks. Is the under tramp beam for/aft and did you add it?
Posted By: Anonymous
Re: Mid boom sheeting, interesting photo - 08/27/06 09:50 AM
the under tramp beam is for and aft. I added it after one of the Taipan sailors showed me how he had lifted his tramp at the back, to improve clearance by lacing to the front of the back beam.
The Mosquito's have this beam in thier rules, so I was used to having it there and attaching the swivelling cleat to it, so I thought once I had raised the tramp it would be easy to put a similar beam on Altered. Of course it also helps keep the tramp higher.
Regards Gary.
Posted By: warbird Re: Mid boom sheeting, interesting photo - 08/27/06 08:34 PM
My PT was set up the same way as Altered (without the spinny sheet) but I decided that fitting to the oval main beam on my aipan project was a hard one. Have you fed into the track or secured to the beam itself?
Posted By: Anonymous
Re: Mid boom sheeting, interesting photo - 08/29/06 11:09 AM
centre beam is pop riveted to for and aft beams using alum angle for brackets.
Regards Gary.
Posted By: warbird Re: Mid boom sheeting, interesting photo - 08/29/06 10:34 PM
Cheers Gary, for all of your help. Will keep you informed of what I do.