Fisher 34 motorsailer

[geconParticipant @gecon]

Thanks to all for the recent encouraging comments.

Tim R: At home when testing, I have operated the winches in a way which I would say must be very similar to when the Fisher was on the water yesterday. But I agree not exactly the same. And it may be that during home-testing I was very close to getting a low voltage warning, but stayed just on the 'acceptable' side. Anyway I'll find out today if the dedicated battery gives normal operation -if the rain stays away. The battery is only 2000mAh so it may not last very long.

George

[Tim RoweParticipant @timrowe83142]

Hello again

I am intrigued about your keel. I couldn't work out how it is fixed to the hull?

Tim R

[geconParticipant @gecon]

Hi Tim, I have just re-posted photos of the keel (from my album) for Chris -on the previous 'page' (20).

The full size Fisher has a heavy enclosed keel built in. This is of course not good enough for model purposes. Therefore the extra keel I have produced is bolted on with two bolts, through the models keel which is filled with about 3kg of leadshot and tiny iron spheres which I bought from Krick. There's also two motors in the bilges and two 5000mAh battery packs. 

The through-keel bolts are actually made from 5mm threaded steel rod with a locknut on each end. The ends of the threaded rods have been sawn over to enable engageing a flat-head screwdriver to hold the rod while turning the nuts. (ouch!) This is starting to sound a bit 'exotic' so I'll  stop the detail discription!

I would not even dream of trying to mould a keel so mine is the wing keel sold by Krick for the Comtesse yacht. The galvanised L-irons used to attatch it can of course be lengthened/shortened to suit. And extra 'leg-metal' can be added later if needed. On a yacht without a Fisher-type keel the legs could be let into the hull and boltet inside -and could even be made adjustble/retractable!

George

Edited By gecon on 02/04/2021 12:38:39

[geconParticipant @gecon]

Clear and bright weather today but the freezing cold wind from the north means I'm staying home. Will test the battery trouble at home for the time being. Try to provoke a low batt warning in comfort.

I read on Google that others have reported on 'low receiver battery' verbal warnings from Graupner telemetery systems.

My Graupner speed controllers are suppose give a BEC supply of 5v and max 5A current. Have not yet tried to think through all the available info, so I'll use Easter and days to come to find out as much as poss.

I may connect up two identical Rx batts 2000mAh / 4.8v in parallel but first I'd like to see the if the problem comes up with just one Rx batt.

George

[Tim RoweParticipant @timrowe83142]

I still can't work it out George.

Could you show a picture of it bolted in place. That looks like a lot of hardware to drag around.

Tim R

[geconParticipant @gecon]

OK, take a photo and post it asap.

G

[geconParticipant @gecon]

[geconParticipant @gecon]

Yes Tim, it's a lot of hardware but it's all keel-weight -and adjustable -and removeable. I had no idea when I started the build of how much keel weight I needed. Letting it hang well below the waterline means less total weight and higher level of effectivity/efficiency.

The main thought at the beginning of the build was that I did not want all this work to 'turn turtle' in a breeze. I have not yet tested it properly either…but I can lengthen the legs if needed and get more effect for very little extra weight.

I don't care if it doesn't sail too well so long as it's not keel-up.    The whole project could be described as 'a lot of hardware' -which it is.

G

Edited By gecon on 02/04/2021 12:58:28

[Tim RoweParticipant @timrowe83142]

Thanks for the photos George

To be honest I was worried about all that weight bolted onto a short section of your main keel. Now I have looked closely at your album I see that the whole inside of the keel is filled with lead shot and epoxy. I am less concerned now but remain just a teeny bit worried because a boat of that displacement can generate quite a lot of energy.

As for hanging it below the waterline, there is a balance between a reasonable and safe amount of stability and a boat that behaves like a lighthouse.

I have to be a bit blunt. For keeping the boat upright I am confident you have cracked it. As for efficiency however, I fear it will be disappointing. Those two flat plates will interact and with the holes and bolts will be very draggy. It will be interesting to know if it goes to windward and how well it might tack.

For me, the keel lacks the finesse you have achieved on the rest of the model.

Good luck anyway with your next trial.

Tim R

[Colin BishopModerator @colinbishop34627]

As someone who has owned a twin keeled yacht I am not convinced that George's arrangement will make all that much difference in practice at model size. It is not intended to be a performance boat. Motor sailers are not noted for their sailing qualities anyway. By their very nature they are compromises.

At full size that sort of arrangement might well be inefficient bit not necessarily so much at model size. I don't think the holes will make any practical difference.

Colin

Edited By Colin Bishop on 02/04/2021 20:31:40

[geconParticipant @gecon]

I agree with Tim that the keel unit is indeed an ugly contraption. I think I wrote last year that only the local trout will actually see it.

When I get the chance to do so, I'll have my Comtesse on the water at the same time and compare relative perfomance. The very round bilge hull of the Fisher is known to roll willingly and my main concern for the time being is to keep the whole show upright….just like a lighthouse

I have been churning the grey cell about my low battery voltage warning and it may be that (in addition to the fact that I have three large winch servos) the tensioning springs on the in-hull sheet runs are also contributing to unecessarily high current drain and thus causing a voltage drop in the BEC system. I'm not sure how the Graupner system is set up but it may be that once the voltage drops below the ca. 4.5v level over some seconds that the system starts an irreversible shut down.

My Comtesse yacht has the same BEC supply and same type of winches and rudder servo but one less winch servo BUT the winches have enclosed drums and NO in-hull sheet runs and therefore NO spring tensioners.

The weather report for the next 10 days at least suggests relatively high winds so I'll use the down-time to do some 'refinements' below decks.

I will also probably fit two identical Rx batts in parallel and not use the BEC at all. Changing more than one thing at a time will mean that I may not know where the remedy lies, but that's not going to bother me so long as I can get it all to work.

I have some other thoughts on all this but I'll 'go away' for a while until I have something more concrete to share.

All comments/observations/criticisms are very welcome and appreciated.

George

[geconParticipant @gecon]

Son-in-law 'beemed down' a few photos of the maiden voyage. He was rather over-focused on catching me in my budget waders to begin with and then there was suddenly other things to 'focus' on due to the power failure on bord.

The propwash from my grandson's DJI drone (and the drone) can be seen in one of the photos so should have som video of the whole show in due course hopwfully with less 'green wellies'.

The yacht floats a bit nose down which is partly due to my having chosen the two foremost boltholes for keel fastening. I may have to locate and drill out the aft holes and move the keel aft. I have always felt that yacht would float 'stern-low'. Looks like it'll be a week before the weather here settles again so back to the yard for adjustments.

George

[geconParticipant @gecon]

The planning cell has been working during the night. It is assumed that the low Rx battery warning and shut-down has indeed been caused by the array of heavy-ish winch-servos. (Graupner 5217) struggling via BEC. The spring tensioners/ compensators in the hull are only stretched at one end of travel for each servo and at any particular time only one servo is at the 'stretching end' of travel. The servos don't sound strained at the end-travel point so I don't think this is a problem although some extra amps are needed to stretch the spring. End travel (and thus, spring stretch) has never-the-less now been reduced a little on all three servos. The Rx is now supplied by two identical 4.8v 2000mAh batts in parallel -which were in fact bought a year ago in case the BEC couldn't cope!

Longditudinal balance and the ugly-bug keel:-

From the few photos I have so far, I note a slight nose down attitude which needs to be corrected. A plan has been made to move the keel attatctment point a little further aft. Thanks to positive inputs on the forum, a new keel arrangement has been drawn up which it is hoped will cause less turbulence both under water and on the forum . The new keel will still not be an object of aesthethic beauty. I don't think I have ever seen an 'aesthetic' add-on keel -apart from the wing keel on Comtesse.

Buying new, even longer keel legs on Tuesday when shops open after Easter.

George

 

Edited By gecon on 04/04/2021 10:34:59

[geconParticipant @gecon]

Produced sail covers for the main and mizzen today. A bit oversize but I do not want to 'squeeze' the sails too much for fear of creasing the luff tape. The covers are probably large enough to use as storm sails.

Not too sure what to do about weighting down the stern yet. Moving the wing keel aft will help, but there is a limit to how far I dare move it. I may have to add weight into the aft bilges but this will just be on the waterline and not give significant added righting moment – just weight.

Don't want an external add-on weight, so will probably test with about 500g zink wheel-weights in the stern bilges and make a deeper keel -fitted slightly further aft than the current one.

George

[Chris FellowsParticipant @chrisfellows72943]

Would having a "keel fin" angled back make any difference or does it act from the mounting points?

Chris

[Eddie LancasterParticipant @eddielancaster]

She looks good George, and lovely setting to sail in.

Eddie.

[Tim RoweParticipant @timrowe83142]

Having the fin angled back would help. It acts through the centre of gravity of the combined fin and weight. The weight would have to be dropped at the aft end by the same angle. The advantage is that it does not increase the displacement and shifting weight is efficient as it lightens one end by the same amount it makes the other end heavy.

It would also change the centre of lateral resistance but I doubt that is a very critical feature of this arrangement.

My views on the keel are well known. Perhaps in Mk II George could introduce some rake aft or keep the fin in the same place and move the ballast weight aft in relation to the fin(s).

Tim R

[geconParticipant @gecon]

Hi all, I did in fact consider having an angle on the legs, but did not think that only getting an average of the aft movement of 'Longditudinal' CofG was good enough.

I have ordered new, longer legs which I will place further aft. Maybe I can even angle these slightly aft from the new attatchment point and get a bit more aft movement of L-CofG. So I'll acheive more depth + aft movement of weight.

Tim, the wing-keel ballast weight is not fastened as far aft as possible in relation to the fins. I could squeeze 10-15mm more if I cut+filed+faired here and there. So I will keep it in mind for the 'MkII' . 

I thought that I might try to have the two legs (fins) join just below the hull to become one single, double-thicknes leg -or fin. I will need some good luck in 'bending at angles'  to 'mirror-bend' the two legs accurately though!  Could maybe ask a local car-body repair garage for help.

I do have a large bench vice but I'm not sure I can bend the 2mm galvanised legs as needed….I'l have a go though!

The first thing I need to do is estimate the required aftward weight-shift.  The canoe stern of the Fisher does not provide much bouyancy compared with amidships so I may not need too much weight to move the L-CofG . I'll have to get back to a lake when the snow eases off and just add weights into the cockpit until the desired effect is acheived. At least I'll get an idea of the required weight-shift. At worst I'll need a bit more iron shot in the aft bilges as well. At at very, very worst…I'll re-paint the the line of the 'anti-fouling'!

Starting today by buying in the new legs and drawing up the required contraption-construction 

Many thanks to all for inputs.

George

Edited By gecon on 06/04/2021 06:20:14

[geconParticipant @gecon]

Showing the 'old' keel and the new planned keel. Will not spend time painting the new one until floatation tests are completed. Maybe even leave it galvanised and silvery!

The new keel will be raked like there's no tomorrow -about 60* to the horizontal I suspect. Any less will not give enough weight transfer. Though I do not yet know how much weight I need to transfer.

Will start sawing-and-bending tomorrow. Will talk to a car bodywork mechanic if I can't bend the bits as required with the tools I have.

George

Edited By gecon on 06/04/2021 19:13:48

[Ray Wood 3Participant @raywood3]

Hi George,

Lovely job she has turned out to be and looks great Can you use the roller reefing on the Genoa to take some power out of the rig ??

Just thought do you really need that contraption bolted on as extra righting moment ?? Your next boat the Colin Archer is similar in size and sails ok without the false add on keel, the hull can obviously support the ballast internally if there were room ?? Just a thought

Regards Ray

[geconParticipant @gecon]

Hi Ray, I expect that the roller furling system could be used to reduce geonoa area. It would need to rolled in quite tightly  to reduce the diameter of the rolled-in sailcloth. Although I would only need to roll in 50%. With it completely rolled in and with the sail covers on, I think it would even sail in a breeze. It will be a long time before I dare test it in much wind I suspect!

The Colin Archer needs about 6kg in the keel for sailing. I think I only manged to get about 3-3.5kg into the Fisher keel…much less than I expected in fact. I have indeed thought of the CA as a comparison and to avoid making the Fisher even heavier (now 10kg) I think the danglig contraption is needed.

The wing itself is only 1kg including the legs so it has to be placed well below the waterline in order to have any effect. I know that Fishers roll quite liberally and to begin with I don't want this one to ROLL too much. I can always unbolt the keel later if it's not needed.

I've been working on the new raked legs today and will do tests as soon as the weather let's up a bit.

Cheers,

George

Edited By gecon on 07/04/2021 18:11:52

[geconParticipant @gecon]

The rather over-dimensioned, plywood frames I have used on the Fisher has also taken up some space which could otherwise have been filled with lead/iron shot.

The Colin Archer -especially the ABS one- has a good bit more bilge and internal keel space for the ballast, than the Fisher. There's also a lot of gear and winch sheets in the Fisher! So much so that I can't work out how I could move the two drive batteries further aft – without moving them higher up as well. The desire to make a scale wheelhouse and aft cockpit also has reduced the choice of where to install gear.

I may -later on- be able to change the under water hull keel profile a bit by adding a deeper, Nauticat 33 type of keel to the underside of the Fisher keel. Maybe I will be able to find someone in Norway who can mould one for me in lead or zinc.

As usual, I have no experience to fall back on, so the main goal for now is to try to avoid a capsize before I get a chance to even try to sail it. Some of the lakes here are very, very, deep

The best would be to build another one to the plans size of 46" And I'm not goimg to do that!

A new keel will appear in a few days! Hope I don't get too much flak!

George

[geconParticipant @gecon]

I've been a bit hampered today by a request to paint a couple of walls in the entrance hall. This evening has been devoted to admiring the new colour on the walls and generally appreciating still being alive -and together.

I have also just been studying photos of full size Fishers and it looks like that the antilfouling/boot top line on my model is too high from amidships and towards the stern. I think that during the painting session, I was too focused on/concerned about  the yacht being heavy and I ended up painting the waterline higher than it should be.

My usual policy is "If it's not broken, don't fix it". Although, as most of us do, I try to avoid building mistakes AMAP, It looks like I have made the mistake of "fixing a problem" which wasn't going to arrise!

I'll complete the keel adjustments during Saturday. It looks like cold, but quiet weather on sunday, so I'll try for an L-CoG check on water. On reflection, it seems to me that stern only  needs to go down <1cm, but the antifouling paint line needs to go down much more! This will have to wait until the weather gets a bit warmer. Not sure if I can scrape off some of blue paint or if I just have to paint over it with white. May not be easy to make it look good. We'll see.

George

Edited By gecon on 10/04/2021 06:20:27

[geconParticipant @gecon]

Still some fairing and filing to do on the new keel, but ready at least for a longitudinal CoG test on the water, Sunday.

The rake angle was drawn at 60* but ended up at nearer 65*. Managed to bend two legs P&S to within a few mm accuracy so I considered that to be 'OK'. Used the original two hull-holes for the fastening bolts. Glue-on wheel balancing (zinc) weights will be used if a bit more aft weight transfer is needed.

I hope the resulting CoG transfer will level it enough to avoid having to paint a new waterline mark. The original plan was -in fact- to have some boot top showing, but it was suposed to be parallel to the W/L!

If all the above works out OK, I will try to make a fairing in thin aluminium sheet to cover most of the visible steel. So that the whole contraption looks more like a fin keel -as apposed to a bit of scaffolding

George

Edited By gecon on 10/04/2021 21:31:40

Edited By gecon on 10/04/2021 21:33:15

[geconParticipant @gecon]

On the water today. Little wind, but good enough Wx for testing. The new raked keel gave the required weight shift so no need for more ballast at all. And no need to repaint the waterline mark.

I had my Roam 3 hat-mounted camera at work while I tested the drive motor and bow propeller with all sails furled/reefed. Good turn of speed and the bow thruster worked impressively -and audibly! Back on land to hoist the sails for sail tests and my grandson asked me if I wanted to take off the lens cap for the next filming session!…..20 minutes of 'sailing by night with sound' on the ScanDisk!

The sails were badly creased after several days under the sail covers so won't reef the main and mizzen very often.

Got plenty of 'footage' after that. There'll be some photos of it all when I get them from my grandson's drone and son-in-laws's camera…in a day or two. Anyway it all worked well. A few refinements will be done on the new, raked, fin keel and the luff sliders for the sails.

The problem with loss of receiver power seems to have been solved by using dedicated Rx batteries instead of the BEC.

George

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