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Author Topic: Swordsman 33 Build  (Read 513 times)

ChrisF

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Swordsman 33 Build
« on: October 25, 2017, 09:29:08 PM »


Being conscious of the fact that I'm mainly hijacking other folks threads I thought I'd better start my own as I'm getting dangerously close to actually building my first boat!

Provision of the workspace is well on its way and should be finished this weekend, I still work 3 days a week so there has been a break since last weekend.


Parts are being collected (see photos) and once I've got some thicker plywood for the keel and bought a scroll saw I shall be making a start. For the prop shaft I've bought a Raboesch maintenance free with a ball race which is rated to 15k. revs. They do a slightly cheaper one rated to 10k. revs and whilst I don't intend to go ripping up the lake that is below what the motor will rev to so I've erred on the side of safety. There is quite a bulb where the ball race is and was concerned at the size of hole required to get it in place! But I should be able to feed it in OK from the inside even if I need to taper the hole through the keel to give some wiggle room. That's why I wanted to get those parts before building so that I can check fitment before the hull is skinned etc.


The rudder is also a Raboesch though I was expecting it to be in brass to match the prop rather than stainless steel - all part of the learning process.


I'm pleased to say that the 600 motor mount will take the 42mm motor though I'm not too impressed with the quality. From eye I can see that it is not bent 90 degrees, there are bad marks where it has been held in a vice for bending and there are rough edges etc. I know it wasn't expensive but I expected better. Some work can certainly improve it though. The fixing holes for the motor aren't countersunk for the screws either. I can either do them or source some flat head ones.


As said the boat is going to be a Swordsman 33 at 1: 12 to match another lovely little Fairey that I have (Inertia/DM knows what it is!) and is going to be the aft cabin version where the roof sits just below the top of the coaming. It is based on the Aerokits kit drawings but with a few modifications to aid building and to make the superstructure lift off as one rather than via hatches in the roof and cockpit. I still have to do some work on the drawings for the superstructure but have done enough to build the hull.


Chris

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ChrisF

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Re: Swordsman 33 Build
« Reply #1 on: November 11, 2017, 10:12:15 AM »

Went to the International Model Boat Show yesterday and bought some more plywood and some other bits and bobs so I think I've got everything to make a start now.

Picked the scroll saw up on Thursday and am just going to open the box, always excited about a new tool!

Last weekend I started printing off the plans but found that they were coming out too small, only two-thirds of the size required! I'm guessing that this is because as well as using the Aerokits drawings I was referring to the original Fairey drawings which maybe hadn't been scanned at full size as I thought.

No matter though as it's just a case of altering the print percentage and redrawing some of the timber thicknesses e.g. the formers, otherwise they will come out too thick.

I won't bore you with a build blog on this as they have been done before by experienced builders but will post the odd photos as I go along, make beginner's mistakes and ask questions.

Chris
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Perkasaman2

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Re: Swordsman 33 Build
« Reply #2 on: November 11, 2017, 04:51:54 PM »

It's a good idea to site your motor as low as possible to the keel. This ensures that your propshaft is as horizontal as possible for the thrust efficiency of the prop and it's alignment axis.
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ChrisF

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Re: Swordsman 33 Build
« Reply #3 on: November 11, 2017, 05:31:09 PM »


Thanks, yes, that's the plan. There were two prop shafts on my drawing as I was working on the actual prop shaft and motor etc. (the one not in red) based on the actual dimensions to see how it would all fit in.

I've since added the engine mount and it's pretty close to the keel. I've got the connector and prop (40mm) as well now so I'll put it all together and see how it looks against the drawing.

The angle of the prop shaft is 13 deg. which from what I've read in other posts should be fine. I can't get the angle much shallower than that.


The prop shaft and motor etc. is the one thing that's been affected most by my adjustment for printing and is now quite a bit smaller, further back and lower in the boat. Hope it fits OK!
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Perkasaman2

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Re: Swordsman 33 Build
« Reply #4 on: November 11, 2017, 05:57:25 PM »

You are on the right track. Good luck with the build. The fairey range of models are ever popular and there are lots on mayhem.  :-))
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ChrisF

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Re: Swordsman 33 Build
« Reply #5 on: November 12, 2017, 06:40:23 PM »

Yes they certainly are and I think I've read virtually everything on Mayhem and some other forums to glean information on the boats and their builds.

I've got two already, a Huntsman and a Huntress (bought already built) but the plan is to build all the different models.

In fact I might start on a Huntsman 28 at the same time as the Swordsman though I've still got some work to do on the drawings.
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doonie

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Re: Swordsman 33 Build
« Reply #6 on: November 14, 2017, 11:12:27 AM »

I thought the prop shaft angle was a bit steep too. I had a boat with that going on and it tried to bury the nose when the power was applied. I see you have a pretty big brushless motor so presume you are after a bit of speed. Maybe a bit of investigating re flexible drive shafts might be a thought.
Just my two bobs worth.
Doonie.
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Inertia

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Re: Swordsman 33 Build
« Reply #7 on: November 14, 2017, 12:49:51 PM »

Enough armchair theory about shaft angles on Fairey powerboats. What matters is what works.
The shafts on a full-size Swordsman are 15 from the keel line. This is done to accommodate two massive diesel engines and their gearboxes under the cockpit floor. The props are almost underneath the transom.
On both of my models of Huntress 23 and Huntsman 31 this angle is 12. Neither of these exhibit any tendencies to porpoise or nosedive. There's a video on You Tube of the Huntress here (from 7.20) https://www.youtube.com/watch?v=JzHGhfT45wo&feature=youtu.be
and one of the Huntsman here https://www.youtube.com/watch?v=uw1C8SfZPS4&feature=youtu.be
Judge for yourselves.
DM
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ChrisF

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Re: Swordsman 33 Build
« Reply #8 on: November 14, 2017, 01:33:24 PM »

I thought the prop shaft angle was a bit steep too. I had a boat with that going on and it tried to bury the nose when the power was applied. I see you have a pretty big brushless motor so presume you are after a bit of speed. Maybe a bit of investigating re flexible drive shafts might be a thought.
Just my two bobs worth.
Doonie.

Yes, I am using a big motor but not for all out speed though I doubt it will struggle! The reason for going oversize is so that it won't be working very hard and will run pretty cool. The ESC will be oversize as well and fan cooled and so will again run cool. I know it's not difficult but I don't want to bother with water cooling.

As DM says the prop shaft angle is well within acceptable limits. The only way I could reduce it any further would be by using a longer prop shaft. Flexible drive shaft on a Fairey, no way!
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doonie

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Re: Swordsman 33 Build
« Reply #9 on: November 14, 2017, 10:09:07 PM »

Wow, I had a look at that second video and the thing looks real good on the water. I was only passing on my thoughts from a previous personal experience. I apologise if I caused a problem.

doonie
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Inertia

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Re: Swordsman 33 Build
« Reply #10 on: November 14, 2017, 11:08:25 PM »

Problem? Not at all, m'duck.
DM
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