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-   -   Northwind 36 (http://www.rcuniverse.com/forum/rc-sailboats-89/2961047-northwind-36-a.html)

bobslr 01-19-2007 03:48 AM

RE: Northwind 36
Hope you get many hours of enjoyment from your NorthWind.
Have you got any picture's you can post,It's always nice to see someone else's work
and they could help the next guy that come's along.
I'm waiting for some water to turn soft too,It's -8C and snowing like crazy here.

Mr. Wolf 01-20-2007 01:17 AM

RE: Northwind 36
Brrrrrr bobslr. Only got to 12 degrees here. Could still sail

cat sailor 03-05-2007 12:16 AM

RE: Northwind 36
Hi All,

Thought I'd give you my impression of the NW36. I'm not normally a radio modeller (just a bit of Tamiya 1/10th scale cars with my sons), my main thing being sailing (full size) catamarans. But when I was in my hobby shop buying a new battery charger for the cars, I saw a selection of RC boats. This got the imagination going (the thought of sitting on the beach by the clubhouse with a cold beer in hand while sailing) and as It was soon to be my birthday, I got permission form the boss to buy one. I selected the NW36, because believing I know a bit about boats, it seemed the best design with a modern high aspect ratio rig and an efficient hull shape. As with most things I buy, they are implulse decisions and I then get on the internet to see If what I bought is any good. I was impressed by the reviews and suprised to see that the 36-600 was a racing class. (I always wondered about the section in my copy of Racing Rules of Sailing about model yachts). I was also impreseed to see that the 36-600 was also a developement class. I have two catamarans, one is a single class where nothing can be changed except for official part from the manufaturere as replacements. The other is much bigger and a developement class which allows changes within a set of limitaions and I have great fun refining the rig and settings of this boat.

I thought I'd give you a few opinions from a full size boat sailor.

The NW36 was pretty straightforward during the build - bearing in mind that this is the first thing I have built apart from the aforementioned Tamiya cars which are perfect and easy to build. As I bought my kit in Hong Kong, the instructions were in japanese, but ABC e-mailed me the English version within an hour of my request. Full marks to ABC there! I was suprised at the jib boom, but this is a compromise for 2 channel RC. I used the original radio box (knowing no better) and all the kit parts except for the railings which I didn't bother with. The only thing I did change was the cord. The blue stuff supplied with the kit looked poor and too stretchy. Full size sailors are paranoid about rig tension - more on this later - so I repalced it with Dyneema kite line which has minimal stretch. I painted the hull with a Prussian Blue spray paint from my local hardware store. It's Chinese and obviously made with chemicals now banned in the West - it's a perfect finish and as hard as anils despite only costing US2.50!

The first sail was in a force 2-3 (5 to 12 knots) and I was impressed with the handling of the boat. I got the impression it was going quite fast, but when I put my wrist mounted GPS on it, I was dissapointed to see it only managed 4 knots. but the main problems were with the sail tension. It was 'blowing out' to a very inefficient shape which gave too much 'heel' (leaning) and thus limiting max speed and pointing (the ability to sail close to the wind). This is because the leach (the back edge of the sail) has too little tension. To remedy this, I eased the mast bend forwards which reduced the belly (fullnes) of the sail, but this didn't help much.

A re-rig introduced adjustable outhaul (an adjustable line on the back edge of the sail) on both the main sail and jib, and an adjustable up haul. The full size boats have an adjustable downhaul (pulling down on the sail at the tack {forward corner}) and this is one of the most imprtant controls on the boat. There wasn't room at the tack to fit a downhaul, so I ran the line from the mainsail head through the forward hole aft of the mast on the tree, forward to the small hole forward of the mast down to the attachment point for the jib via one of the kit adjusters. The results? Much much better. On a second sail yeasterday with much lighter winds, I was able to make the same ajustments I would make on the big boats to improve matters. However, not actually sitting on the thing and being able to see what is happening close up made for lots of trial and error - not withstanding the fact I had to bring it back to shore everytime an adjustment was made.

But, there is still lots of room for improvement. I have a weak servo on the mainsheet. But as on my big Cat, I don't have enough strength to sheet in (and I'm not a small chap!) and have to head up (point into wind) to relieve sheet tension to sheet in, I don't see this as much of a problem at the moment. But it might get changed. The booms are hopless - they flex like mad with any gust losing a lot of power. So these are going to be changed. The vang is a piece of junk. Vang tension is crucial on single hull boats (it is one of the main sail shape controls) and this will also be changed with the jibs. And the sails aren't very good. The main an outdated design, more modern designs have a squared off top (to unload force from the top in strong winds as the top of the sail gets blown out), a straight leach and full chord battens. The jib is too wide - modern jibs are more of an airflow director to increase the efficincy of the mainsail. It too is too slack and could benefit from more leach tension and full chord battens. I expect once made, these modifications will allow to boat to sail close to the wind with less heel. I will report back when they have been made.

I notice the 36-600 class rules allow for a spinnaker. I have future aspirations for an assymetric gennaker, butthis will require two winch type servos. I'm not sure how much this will improve the handling of the boat, but it will be a lot of fun!

I don't have anyone to race against at the moment, but with the interest I got from my sailing club fellow members, this might change soon!

Happy sailing,

Cat Sailor.

Guiri 03-07-2007 11:59 AM

RE: Northwind 36
Interesting post cat sailor and generally applicable to all R/C sailing boats. The problem is that, for me anyway, there are already too many adjustments that can be made[sm=red_smile.gif].
For the sail control, both Futaba and Hitec sell sail control servos with enough muscle for the job. However, you may have difficulty shoe-horning them in to the radio box. The Cirrus P-CS704/MG is an alternative with a much smaller footprint and 13 kg/cm torque at only 4.8 V.

cat sailor 03-29-2007 09:53 AM

RE: Northwind 36
Yeah, it does seem there are enough adjustments already. However, in full size boats the guy who wins the race is usually the one who has given himself the best advantages both in tactics and techniques. Often, the winner is the first to the windward mark. He has nearly always had a good start - and his into wind performance is superior as because he has set his sails correctly.

So far, I have replaced the kit's flexible plastic booms with lengths of 10mm aluminium tubing and attached both sail's clews to sliding rings which are adjustable with the outhauls. And the vang has been replaced with an adjustable cord. The result is a much better sail shape with a much tighter leach and a vastly improved into wind performance. There is noticably less heel and a lot less 'billowing' of the mainsail. However, there is room for improvement, but things will not get any better with the kit supplied sails. These will be replaced in time. Also, after just 4 sailings, I have noticed that the kit sails have already stretched.

I don't have a problem with the kit's mast. With proper bracing, it's as stiff as it needs to be. As as for the amount of bracing, as with the sails - the stronger the wind, more tension is required.

I have identified more powerful servos and one will be fitted soon. However, I don't find things as bad as some people have done on this site and I think this is possibly because having transfered more of the power to the mast than the boom with more efficient sail adjustments, there is less pull on the mainsheet. I find this is certainly the case with my full size boats - they are a lot easier to sail in strong winds with the sail flatter and a tighter leach. For this reason, I'm considering a 6kg servo (3kg servo currently fitted) which is a compromise between power and my budget.

A couple of things I did during construction which I could have mentioned in my first post. I used an epoxy fillet around the keel bullet to strengthen it - this works fine. I also glued a 1 pint water bottle into the hull (with the cap on!) forward of the mast to act as bouyancy should things go badly wrong. All full size boats are required to have enough bouyancy to prevent sinking in the event of complete flooding. Also, I made a gasket for the cover by smearing a thin layer of silicone sealant on the join, allowing it to dry thoroughly before screwing it down. So far, I haven't had one drop of water in the hull.

And I now have someone to sail against as a guy came up to me and said he sailed model yachts and could he come and sail at the boat club as well. Something to do with a fridge full of cold beer I think!

Happy sailing.

Midget 04-12-2007 11:00 AM

RE: Northwind 36
1 Attachment(s)
Hi cat sailor-

Thanks for you interesting write ups.
Ive lernt a lot from what you said.
I to have thought about a kite, but i think it will over power the boat in heavy winds.

Just thought I would give you guys an update on how my north wind is going.
-Ive just replaced the fittings with mettle because some of the plastic one's started braking.
Also, Ive just finished making some new sails, so ill see how they work out tomorrow.

here some pics of the new sails and my new skiff

Guiri 04-13-2007 01:50 AM

RE: Northwind 36
You have the advantage of a full size sailing background, which must help a lot when it comes to diagnosing and curing problems. Just getting mine to sail with a neutral helm was difficult enough at first. Competition must be another motivation and there isn't anyone else sailing near here. But its still fun and relaxing.
Btw, is there any reason you chose aluminium over carbon fibre for the booms?
Your experience with sails stretching seems a fairly common problem with kit boats. The cheap alternative seems to be the plastic gift wrapping, which has served me well. It seems to be polyester with a weight of about 50 g/sq. metre, but its cut edges do need reinforcing unless cut with a fine tipped soldering iron. The panels, which are only joined with double sided adhesive tape and not sewn, have stood up well to a fair bit of abuse.

Midget 04-13-2007 03:53 AM

RE: Northwind 36
1 Attachment(s)
Hi guys-
Well I wasn't of to a good start today, First i forgot my reserver so i used my other
one which than Fried my Hump pack. So i had to use my other battery pack, Which was ok
because the wind wasn't that strong.

Anyways...She sailed really good and tacks so much nicer than with the kit sails.
I had to use my old job boom because my new one snapped, so i couldn't make as many
adjustments as i would have liked to.

Heres some pics-

Over the edge 04-30-2007 01:57 AM

RE: Northwind 36
Hello from Utah, I just dusted off my Northwind, first time in about two years. The boat still works great. I am putting in a new radio though, the old one was cannibalized out of an old Traxxas truck I had. It (the radio) finally bent me the wrong way with the intermittant response. So I am putting in a new Hitec Aggressor. I was reading many of the older posts about servo selection for the sail. I went with a Hitec HS785HB. It works great... but the problem I came across was overtorquing of the ABS plastic parts. I solved that by removing the tab on the one side of the servo arm that attaches to the sail arm and replacing it with a piece of brass square stock. On the sail arm itself, I used a piece of brass square tubing that fits tightly inside the other. I tapped the square stock- which took a couple tries and a couple taps- and secured them together withI think a 2mm screw. It seems to be holding up well.
I was also wondering if anyone has a found a way to put a sail drum servo in? Or is that just too big of a pain to deal with?

bobslr 04-30-2007 04:05 AM

RE: Northwind 36
A sail drum servo would'nt really be neccesary,I posted some photos and drawings of mysail arm setup and it work's very well but you would have to get rid of the stock radio box.

YZFMattayo 05-19-2007 03:44 PM

RE: Northwind 36
Sail vs Power
One of my co-workers has had a Coast Guard 110 WPB R/C boat on his desk for the last year. Once I brought my North Wind in to put in my office, I heard nothing from him other then how fast his CG 110 is, and how it would scream past a "blow boat". Well, I finally had enough and challenged him to race to shut him up. All I heard until the race took place was how much pride I was going to lose. So on race day, there was about a 15 knot wind, and about six inch chop. The course we agreed upon was about two hundred there, and two hundred feet back. The gun went off, and away we went. Not only did the NW scream past the 32 inch long 110 WPB, but the NW won the race by roughly 300 feet, and I was also able to circle the power boat prior to the finish line. I must say he and everyone else that attended our little race has a new respect for "blow boats". I think one of the other guys from work is making a video of the race, and if he does I'll post it for all to see a grown man cry.


Mr. Wolf 05-22-2007 08:25 PM

RE: Northwind 36
The new sails and up grades look good Midget.

wingnut11 05-23-2007 01:28 AM

RE: Northwind 36
high- just read entire thread. woke up one day, and decided i wanted to sail.first I bought a boat, then i bought a book ( sailing for dummies). I am not new to RC , just new to boats. All of you seem very helpful. I' ve already figured figured out i need to modify and make better some of the parts.
every day i take pics to show my progress. if anyone new to this wants them - let me know. i'ts time to start rigging. can i just pay someone to do this?:(

schmism 06-06-2007 12:54 PM

RE: Northwind 36
Well i had mine out on the water for the first time in like FOREVER....

it was fun to see her raceing down the pond.....

but boy was i rusty.... I need to dig up the "how to sale tread" as in current setup im stearing into the wind when i tack which takes constant rutter control to "behave"

That and i ran through a spot of floating spooge on the pond and then things went all haywire, just as the wind started picking up, i had a h3ll of a time getting it off the pond and when i finnally did i was inspecting the rutter and whatnot and look up and my jib boom is snapped [X(]

bout time that sorry plastic stick gave up... forces me to finnaly upgrade to those arrow safts i got from a friend a year+ ago....

PS the office complex i work is surrounded by a series of detention ponds that say dry most of the winter.... but this spring they filled up finnally so im going to keep the boat up at the office and sail it there on those ponds as the surroundings are flat and we have good wind.....

[alan k] 06-09-2007 03:42 PM

RE: Northwind 36
hey guys its been a while. i finished the rigging and sails and all and im looking at the innards. Can i use a stronger servo with out changing the radio box that came with the kit. And i want to change the way the servo interacts with the sheets. I used to live on a boat and i know what kind of forces the wind can exhert. The plastic arm looks too flimsy along with the other servo pieces. Any ideas???

Sailingkid 07-03-2007 06:19 AM

RE: Northwind 36
Hi everyone, I have had my Northwind 36 for almost 2 years. I am 13 years old as well. The first time i sailed it a swan came along and as we didnt have the hatch cover on because we forgot the tape the swan flattened it, and sunk it. My Dad dived in and saved it and we dried it out with a hair dryer. I ahd had a lot of fun with it so i decided to make a Mylar"sports" mainsail. Ity had a huge square top and i had to take the backstay off. The first time i sat it outside in near calm winds, the sheer power of the thing ripped the radio box out of the bottom of the boat. I re rigged it to standard, Exept i left the rope vang on because i find that the topp of the main flags off when the boat gets overpowered upwind but downwind it sets and the boat flys along. So after about a year i finnaly had a sail and it went quite well exept it was only blowing about 2-3 knots and the top half of the main was already flapping and the boat was heeling considarably. That leech genarates an extra 50% of power i think compared to the standard plastic vang. To do this i pulled the plastic vang off, left the ball at the bottom of the mast, then ran a peice of that string that came with the boat under the existing ball and onto the unused cleat style fitting, leaving the vang completly ajustable.[8D]

Sailingkid 07-05-2007 01:00 AM

RE: Northwind 36
I sailed my northwind this morning. It wasnt very windy but my mainsail is over streched and the leech(trailing edge) is now flapping exessivlly. Does anyone have any experience with those vision sails racing rigs? Because im sick of losing all this power as soon as it starts to get the rail anywhere near the water. [:@] I still went really fast though. I cant belive the exalaration this thing has! Then this afternoon i gave it a custom keel bulb paint job(bright orange) and i also painted some of the deck hardware mettalic blue. :D

Mr. Wolf 07-07-2007 04:43 AM

RE: Northwind 36
Hi everyone.
Been out and about sailing the Northwind down at Irvine Lake here in San Louis Obispo since it's been to hot up here in the North part of the county. Although the lake is wonderful its pretty low this summer because of the lack of rain over the winter and spring.
[alan k] most of us here have found the palstic arm is very weak and will be eventually twisted and striped from the sail I made a new one out of fiber glass board bought one line from a hobby supplyer. As you mentioned the strength of the wind, it may pull your sails servo from the servo box that comes with the kit. You may be better off building one of your owne out of wood or alumium to secure your servos in.
Hi Sailingkid. Sorry to hear your boat had a ruff start. I think from reading your post about the top half of your main sail flaping excessivly it may be from your main sails boom warping. The plastic boom that comes in the kit does this alot from what I've read. When I buildt my boats I replace the whole sailing rig with carbon fiber and malay sails. As for the boat keeling over alot you should let out your sails to bleed off the wind when it is doing that. The paint job sounds interisting. Would like to see any pictures.
So anyone been watching the Americas Cup races? As buetiful as Valencia Spain is. I would have liked the cup to come to San Francisco, California.
Everyone one have fun sailing

A little government and a little luck are necessary in life, but only a fool trusts either of them.
P. J. O'Rourke

Sailingkid 07-08-2007 05:08 AM

RE: Northwind 36
Yeah Mr Wolf maybe ill get some carbon for the booms, but did you make your own mylar sails or did you buy them?[&:][:-]:D

[alan k] 08-01-2007 06:04 PM

RE: Northwind 36
Over the edge, with the Hitec HS785HB servo for the sails did you have to use a different setup for the radio box or did it fit with the stock in the kit. thanks

[alan k] 08-02-2007 05:34 PM

RE: Northwind 36
hey guys,
im done rigging and have everything set except for the radio stuff, i shouldve probably done that first thing but i couldnt help myself. It looks pretty straight forward even with the rigging up. Anyway i was wondering if the servo for the rudder controll could just be a standard servo with 57 ounces of torque. or do i need a special servo for that one too.

flybug 08-02-2007 05:48 PM

RE: Northwind 36

ORIGINAL: [alan k]
hey guys,
im done rigging and have everything set except for the radio stuff, i shouldve probably done that first thing but i couldnt help myself. It looks pretty straight forward even with the rigging up. Anyway i was wondering if the servo for the rudder controll could just be a standard servo with 57 ounces of torque. or do i need a special servo for that one too.
AlanK, grats on your project, for your rudder control a standard Hitec HS311 or equivalent in other brand will do no need to go over board on that. Now for the sail servo if you don't have one already you may want the Hitec HS755MG or the HS765 (some people use the HS715 with no problems) or any equivalent in other brands.
Good luck and let us see some pictures:D

[alan k] 08-03-2007 11:58 AM

RE: Northwind 36
1 Attachment(s)
heres a couple pics of the boat
thanks for the advice

Subw00er 08-07-2007 07:57 PM

RE: Northwind 36
Hi all, hope you can help! I'm having a problem with the rudder arm "stripping" on the vertical
rod connected to the rudder. The plastic actually cracked, so I need to
do something. I recall seeing pics where people changed to a more
standard control arm - even metal perhaps?

I was thinking about just "sandwiching" the control arm in between two
nuts, but this doesnt seem to be an idea solution because it would
still rotate if forced. I was wondering how people secured their
aftermarket control arms on the rudder rod securely? Pics would be

[alan k] 08-08-2007 09:15 AM

RE: Northwind 36
Hey guys,
Im looking to redo the main boom, initially i used solid aluminum stick as the boom, but the way i had the sheet and foot attached to it will not work. im thinking of using an arrow shaft, but the aluminum ones look and feel like they will bend, and with the carbon fiber ones, at the end closest to the mast youd have to bend it to fit the plastic pin. Does carbon fiber bend like that??
Any ideas are greatly appreciated.

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