Saturday, July 18, 2015

Fila #89 b-rigg fun and "Narrow" the F5g

While in Premantura i got the chance sail the new Fila with the b rigg.
I am satisfied with the result. Handling or speed aren't revolutionary but hadling is difinately improoved over evolution. Tacking is easier, There is also less nose down(logicaly, both boats have a wide stern, but fila has the hull shape made out of "circles", meaning there is less volume far from the centerline and low down, far from deck. So the rigg can "sink" the stern abit) Upwind, that is aspecially noticeable when bearing away.
I am still not happy with handling while reaching. The boat is forced to sail where it is pointing. Using even a small amount of rudder means loosing loots of speed. The bow is also too low in the water. Usually waves are not exactly perpendicular to the wind direction. Meaning that the boat can fly(go as fast as it can) one way, making that course really fun.
Reaching the other way sucks. Bow keeps digging. It is too low in the water. With all new components the boat will be circa. 150-200g lighter than it is on the photos but that won't solve the issue. It needs some kind of foiler under the bow, since no real lift is obtained from the sails.
Reaching the fun direction, note: bow up :D
When a wave ends(and there is no wave in front to plow into) there is enough downforce from the foil to sink the boat a couple cm.
The boat stays flat. It just sits deeper. Yes it is bad for the speed, but still better than a nosedive.
Downwind is just so much fun whe ne wind is above 15 knots.






Upwind:

The jib is 3 seasons old now. But the shape is still good

Handling upwind is excellet, or maybe just matched to my preferences.

I was too lazy to take blog worthy shots of the boat sailing with the a rigg. So it is going to happen in the next days, here in home waters.
I am just waiting for a day that won't be 35C hot, because that heat kills the morningbreeze, which usually develops into a steady 10knots if the temperature stays below 30.

Meanwhile the bulb for fila 89 is almost finished, next is the carbon keel fin.

Also i am working on a narrow f5g and rg65 with shadows borrowd from the f5g.

The f5g will weight somewhere between 1200 and 1270g, max. beam will be 6cm. The narrowes f5g ever.(exept if this gets finished sonner: http://forum.modelarji.com/viewtopic.php?f=13&t=90474)
It's atribute will be weight and low WSA, it has less than half of the WSA than Evolution!
The construction will be really simple. It will be hot wire cut from a block of stirodur/depron foam, the edges will be sanded to a 10mm radius and it will be glassed with epoxy. Foam will be removed with acetone. Not a revolutionary tehnique but efiicent with time.
The goal of the boat is to set a new standard for sailing in light winds(koseze) and to see how a really slender hull behaves at speed. With help of my foiled rudders i am plannig to sail above hullspeed, for now probalby only downwind.

F5g national class races - video clips

I uploaded some clips from races.
More are to come.
Video curtesy goes to Peter boat No. 68

1. race of the year took place in koseze, where the wind was surprisingly good.
I am sailing Evolution #86, Father is sailing Fila #87

8 races were sailed, the battery ran out for the last race. And so did the wind.
Results should be here: http://forum.modelarji.com/viewtopic.php?f=13&t=91554
But they aren't, they are very late, a few months late. Not sure why.

3rd race of the season was in Radeče, on a river, current was present. Nearby storms made for gusty and shifty condtions. Not to my liking
 But Radeče is always an interesting race, me and father were late, so we sailed with open decks, that resulted in fila sinking, almost to the bottom.
The boat got rescued, the battery was changed, and it sailed the rest of the races with a deck lid, with no problems. Hobbyking cheap servos ftw!

The race was tough.
The results are here: http://forum.modelarji.com/viewtopic.php?f=13&t=91830

Friday, July 10, 2015

Fila 89 - technical details

Fila 89 is the second fila boat i built.
The goal was to improve the sailcarryingability while maintaining the excellent handling of the boat.

The the original fila handles as good as any of the rc sailboats i have sailed, and still sets the standard for comparison for me.

The new boat has the mast and the keel box set further backwards to compensate for the expected bigger rigg, and longer keel.
The goal was also to sink the stern at heel angles bove 25deg(with the weight further aft and the big luff), lifting the bow. Giving it the ability to jump waves, reducing the entrance angle and improving agility.

It is not finished yet. It has a rigg and keel borrowed from evolution. Later it will recive a rigg identical to evolutions.

But the keel will be different.

The rudder is the same as evolutions.


The keel is 58cm long from the bottom of the hull to the bottom of the bulb, the bulb is 700g the keel 140(too much, but hey its aluminium)

Some diy stuff, 2.5mm allen key makes sure the backstay clears the sail and the boom

Why plastic sucks, the wang is loosing colour, and the right-most piece is bending despite 100% infill

the jib pivot is set further furward on this boat. The idea is to get the sails more paralel. This way the jib should depower later while keeping the desired gap at the back of it. And the ce doesn't move as far back when reaching(a better explanation would be that the jib remains more sheeted in, but the gap to main is still the same, the jib is more parallel ti the center line).
This is the best change compared to other boats. It makes bearing away much easier!, and smoother, there is no need to depower the sails all the way to the top of the riggs wind range.



This ,aom/sheet-servo position is a first for me. and it will stay this way for boats to come.
There is much more "hand space" inside, but it is a pain to change servos...  
note: 3d printed servo arm(seems to hold the 17.7kg@1cm@6V for now, it is 8.5cm long) and mount


3d printed mastbox and rudder servo. Positioning of the servo is not ideal, but the woodden support was to narrow for longitudinal mounting. The link is just temporary.
Note: this boat uses only stainless steel fittings and screws, the hooks for the stays are 1mm tig welding wire, the screws m3 stainless, whatever lenght is required.

I managed to loose the little 10mm tube that slides over the mast crane to extend it. Recently someone said that zipties are a temporary lifesaver. But all life is temporary they say..   ..mening this should break soon.




When i recieved the hull there was a big hole where my jib sheet outlet/hook would be. This flying hook/outlet the idea came from some beach cats and fireball dinghies, it is accompanied by the "standard" jib pivot tensioner.

Sailing tests concluded that the boat is floating on her desired static waterline(probably with a dispalcement of 1600-1700mm3), i have yet to weight her.
It also needs a keel with more surface, or more lift. since it sometimes goes sideways when not at ful sailing speed and it drifts quite alot when standing still.

I have a special keel planned for this boat, one with area concentrated just below the hull, and a strut hanging from it deep in the water. Similar to mal smiths boat here:http://www.users.on.net/~malcolmandjane/750.html

A post with sailing photos follows.





Blog active again, a.k.a. July update

So i have been away for some time.

No real reason for that.

Mostly, i have been driving cars and developing my own parts, for drifting/performance.

I've repaired some cars, crashed some and i am not nearly done, driving&experimenting, having fun&crashing..

..but i haven't left the rc sailing hobby.

All along i have been sailing evolution and for the last month or two fila 89, with mostly evolution guts(rigg,keel,rudders). Fila 89 is fast, not much faster than evolution, but handles better, gets up to speed faster. It will be raced in the end of august in the model olympics. Trying to take all the top spots from the get go.
So far in the F5g sailing season i have been doing great. Not sure if the boat(evolution) is  fast or my sailing is that good :D.
Videos of races follow on yt.
Posts on fila 89 follow.
A super narrow f5g boat follows.

The Jif got it's fair share of sailing too. Rg's are funny as hell, 270g of ballast on a 44cm ultra thin bendy keelfin and a full sailarea 90cm tall rigg make for a boat that is capable of carrying the same rigg up to 15knots, gusting to 20.
Damn that v botom can plan downwind. Not sure if it is actual plnning but is exceeds the hull speed for sure.
Project angeldust got dropped after a desk lamp heated the 3d printed plug so it got deformed.
A post on jif follows.

Footys have been down tho. I made it to the goldcup in Germany, but with prototypes of questionable speed. With noone to compare to, and not as much fun as the faster rg65 and f5g i won't sail footys often in the near future. The goldcup result confirms that.
Footys didn't grow roots in Slovenia, despite me bringing the footys to every rc event i went, giving them and lendind them to anyone interested.
Only two Karo replicas were built, but they weren't really race capable.(yet)
Now i am to busy&have other interests to actively promote footys here in slo. But footys are still great boats, and i will, maybe, take part in future goldcups with a borrowed boat(ICE would be nice, or a Slim perhaps..)

Rc-sailing.net, i have been following the forum for years, before i made my own blog, before i've built my first footy.
Now everytime i try to enter it a vbulletin message appers: "Sorry. The administrator has banned your IP address. To contact the administrator click here"   ...i have written (clicked) messages to the admin. But with no reply, not sure why all the devices i use got banned, And i don't think i've done something wrong according to forum rules.
I have yet to try other contacts to reach the admin.
If anyone has any info on the subject please contact me.
From time to time an interesting topic does pop up in the forum, and i would like to be a part of it, or at least read it.


And that would conclude the "july update".