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[Flying Sparks]

Hi Derek

 SWMBO just don't understand do they  Whats a Cygnus fishing boat?

Wow, your going to fit two motors, very cool. Have you thought about battries yet? NiMi or LiPo? Should have plenty of power though if you can find enough capacity for a decent run time.

I will post some photo's of my Huntsman soon

Phil.

[Bradley]

Hi Phil,
I intend using NiMh packs which should give me plenty of power and run time.
If you have a look at this posting you will see what the Cygnus fishing boats are like.  No photo of mine there but some great ones by mayhemmer Ray111 -

http://www.modelboatmayhem.co.uk/forum/index.php?topic=21091.0

Derek.

[Flying Sparks]

Hi Derek

I see what you mean by a Cygnus now, very nice 

I saw the You Tube video of the very fast Cygnus as well 

Thanks

Phil.

[Flying Sparks]

As promised, some photo's of my Precedent Huntsman. The boat is in reasonable shape, the main issue the crack in the transom and rear hull sheeting on the "V", some bits of trim have fallen off or broken. Nothing serious. One observation and I'm not sure if it shows up the picture is the prop shaft tube looks set at a very steep angle and a long way back from the prop. Maybe thats how it should be but I don't have the plan to check.

Phil.

[Flying Sparks]

Oh yes no I've posted the photo's I've remembered something else, there is a big lump of lead in the rear of the hull, I intend to replace that with batteries as I don't like carrying around weight that does not earn its keep and the motor mount position looks a long way forward. I reason that if the motor moves rearwards then less weight will be needed at the back to balance correctly.

Phil.

[Bradley]

Looks like that will be a nice boat when you have finished the refurb, Phil.

I have another problem now - I have got the brushless ESC and programming card and could not get the motor to run properly after several attempts at programming - I could get it to run ahead but after about 10 seconds it stopped and I could not get it to run in reverse.   However after a little advice from elsewhere I tried the programming again, both with and without the programming card and it seems that there is a problem in reversing brushless motors in that, after running ahead, I found that it would reverse by flicking the throttle stick on the Tx down several times.   I think that this is no use on a fast boat so am considering reverting to thoughts about brushed motors, eg. Graupner 700 or similar - any thoughts anyone, please?

Derek.

[Bradley]

Sorry about all the bold print on the previous posting - did not work out as intended. 

[HS93 (RIP)]

sounds like you have a delay turned on, some have it to save controllers getting a blast of current while still going forward, I have player with 3 with reverse the first two cheap ones where a problem to set up and turned out to be to powerfull with the motors I had but reverse was there when needed, the other type are a lot dearer you can set them up in two min and they are so smooth in forward and reverse I will never buy cheap brushless controllers again go for castle creations

http://www.castlecreations.com/products/products_boat.html

Peter

[Bradley]

Many thanks, Peter, that gives me another line to work on.  There is a Giantcod link earlier in the posting and the illustration of their ESC looks identical to the Chinese one I have been trying to set up.

Derek.

[Bradley]

Wow, just had a lookat the castlecreations website.  I have no doubt that they are fantastic ESC's but the prices  .  I'm afraid I would have to give up my hobby before I could even consider affording them. 

Now got to start thinking more along the lines of brushed motors (Graupner700 ???), etc. 

Derek.

[Perkasaman2]

Hi Derek, You have a large hull and have single prop/ double prop options. Best contender single prop is probably the MMB 900 on high volts. Best motors on twin layout are probably 700 BB turbo running 2 x 45X props at max 14.4v. These brushed conventional options are cheaper proven performers. Siting  engine(s) more  forward in the hull enables a more efficient horizontal axis for shaft/prop alignment to deliver optimum thrust along the keel. Many  large fast coastal craft deliver thrust at quite acute shaft angles because of expediency/limitations of inboard machinery. Our bow/hull shape obliges planing conditional proprtionate to forward speed. A prop at any angle other than horizontal impairs it's effiency/presentation to the direction of water flow. Power tilt/trims tabs/wedges all enable tuning of good/bad designs alike.
The worst designs exacerbate these thrust issues when they are planing - The RTTL is an example of this contradictory design.
High output NImH packs are getting cheaper and are more multi useable and offer great weight saving/easier placement with both layouts. I sympathise Derek ,you've got some hard decisions.  A great thread.  )I doubt whether I've actually helped/made it easier.

[FullLeatherJacket]

One observation and I'm not sure if it shows up the picture is the prop shaft tube looks set at a very steep angle and a long way back from the prop. Maybe thats how it should be but I don't have the plan to check.

Phil
The plan for the 1/8 scale Huntsman has the prop nut 200mm back from the end of the keel, so this measurement should be 145mm on the smaller model. Yours does look a bit too far forward.
FLJ

[Shipmate60]

There is also the option of 2 x MMB 900's on 12 volts.

Bob

[Flying Sparks]

One observation and I'm not sure if it shows up the picture is the prop shaft tube looks set at a very steep angle and a long way back from the prop. Maybe thats how it should be but I don't have the plan to check.

Phil
The plan for the 1/8 scale Huntsman has the prop nut 200mm back from the end of the keel, so this measurement should be 145mm on the smaller model. Yours does look a bit too far forward.
FLJ

Hi FLJ

Thanks for the measurement but I believe this model is smaller scale than 1/8 at 34 inches long I guess nearer 1/12 scale. What I did mean to say is the end of the prop tube looks too far forward. I think I will remove the tube and fit a new one further back and at a shallower angle.


Derek

I would persevere with the brushless. I have very little experience with brushless in boats so far but I do have quite a bit with brushless aircraft. I will never go back to brushed motors now, the gains with brushless are so big it's just not worth messing around with brushes.
This weekend I tested a boat (SHG Shadow) that last time out several years ago had a Graupner speed 600 motor fitted, the boat went OK reasonable speed but motor got very hot. I fitted a brushless outrunner (£20) that is the same diameter but half the length of a 380 motor and I used a cheapo chineese aircraft controller (£13) with no reverse, boy did it go, the boat could not handle more than half throttle but it was planing around the lake nicely.
My Huntsman will defiantly be getting a brushless and a similar controller to what I used in my Shadow but maybe with a water jacket on the ESC.

Phil.

[FullLeatherJacket]

Hi FLJ
Thanks for the measurement but I believe this model is smaller scale than 1/8 at 34 inches long I guess nearer 1/12 scale.

No need to guess any more - it is  1/11 scale. A 31' Huntsman @ 1/12 scale would be 31". The measurement I gave was calculated as 200 x 8/11 = 145. You can take my word on this - I designed both of the original Precedent kits  
FLJ

[DickyD]

So where does the prop shaft go on a 1/11 scale Dave ? 

[Bradley]

Hi Guys,

Many thanks to all of you for your contributions and suggestions which are all helpful .  Now to some head scratching .

All suggestions greatfully received .

Derek.

[Flying Sparks]

No need to guess any more - it is  1/11 scale. A 31' Huntsman @ 1/12 scale would be 31". The measurement I gave was calculated as 200 x 8/11 = 145. You can take my word on this - I designed both of the original Precedent kits 

Wow, thanks FLJ, talk about the reply from the horses mouth  This must be one of the most longstanding boat kits and still in production!!! Nice design FLJ and I hope you make money from it.

A quick measure of my Huntsman and guess what, the end of the tube is 200 fromm the end of the keel. Looks like somebody got their measurements wrong. 145mm looks much more like it.

Thanks

Phil.

[John W E]

Hi Derek, You have a large hull and have single prop/ double prop options. Best contender single prop is probably the MMB 900 on high volts. Best motors on twin layout are probably 700 BB turbo running 2 x 45X props at max 14.4v. These brushed conventional options are cheaper proven performers. Siting  engine(s) more  forward in the hull enables a more efficient horizontal axis for shaft/prop alignment to deliver optimum thrust along the keel. Many  large fast coastal craft deliver thrust at quite acute shaft angles because of expediency/limitations of inboard machinery. Our bow/hull shape obliges planing conditional proprtionate to forward speed. A prop at any angle other than horizontal impairs it's effiency/presentation to the direction of water flow. Power tilt/trims tabs/wedges all enable tuning of good/bad designs alike.
The worst designs exacerbate these thrust issues when they are planing - The RTTL is an example of this contradictory design.
High output NImH packs are getting cheaper and are more multi useable and offer great weight saving/easier placement with both layouts. I sympathise Derek ,you've got some hard decisions.  A great thread.  )I doubt whether I've actually helped/made it easier.

Hi Perkasaman I think you need a new book as the Peter Du Cane - one is no good for the design of the hull of the Fairey Huntsman or the Swordsman  (totally different rules) they are deep ‘V’ hulls and the RTTL is a flat ‘V’ hull – so different propeller shaft angles.  Also there are different hull trim angles – try the book Milestones in my design  by Renato sonny Levi – he designed the offshore power boat Surfury.
 
Aye
John e
bluebird

[funtimefrankie]

No need to guess any more - it is  1/11 scale. A 31' Huntsman @ 1/12 scale would be 31". The measurement I gave was calculated as 200 x 8/11 = 145. You can take my word on this - I designed both of the original Precedent kits  
FLJ

How do you come by "strange" scales...is the desired model size decided on first and then worked back to the full size for the scale?

[FullLeatherJacket]

How do you come by "strange" scales...is the desired model size decided on first and then worked back to the full size for the scale?

I did what I was told by The Boss! It was more or less as you say, however.
FLJ

[funtimefrankie]

I did what I was told by The Boss! It was more or less as you say, however.
FLJ

So the wife set the scale ???

[FullLeatherJacket]

No - it was John Rudd, who was one of the two partners in Model Avionics. They made the first kits at their premises in Woolwich, and then the business became Balsacraft International Ltd and moved to Watton in Norfolk. John died in 1999. His widow Tricia and her brother Ian Hull continued to run both Balsacraft and SLEC, but the inflow of cheap ARTF model aircraft killed the market for all UK kit manufacturers. The rights to the Huntsman and Perkasa boats passed to Anglian Model Supplies. SLEC still make one or two of the old aircraft kits and continue to supply balsa, ply, strip wood and plastic injection-moulded accessories.
My design work wasn't done on a royalty basis - unfortunately!
FLJ

[Flying Sparks]

FLJ

Thanks for the interesting story, it's nice to know the roots of where some of our models come from. The cheap ARTF kits have not completely killed of the builders kits there are still some around and I notice that SLEC are producing some of the old Balsacraft kits and also a small boat kit called the Samurai.
What would be nice is if the Huntsman and Perkasa were produced as a CNC or laser cut kit that slots together. I've built a few aircraft kits from this method and they are so simple to build, just slot together and then squirt on the glue! They are much easier to build than a die crushed kit with parts that have to be reworked to fit.

Do you still design models?

Phil.

[DickyD]

Hi Perkasaman I think you need a new book as the Peter Du Cane - one is no good for the design of the hull of the Fairey Huntsman or the Swordsman  (totally different rules) they are deep ‘V’ hulls and the RTTL is a flat ‘V’ hull – so different propeller shaft angles.  Also there are different hull trim angles – try the book Milestones in my design  by Renato sonny Levi – he designed the offshore power boat Surfury.
 
Aye
John e
bluebird