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[andi4x4]

Ahoy Shipmates !

 Newbie here with a new build Brave Borderer on a 36" fibreglass hull.

I have just started building from the Model Maker plans that were supplied with the hull. I first purchased this kit about 15 years ago and began building, then lost interest. Over the years the hull has been re-used a number of times on "pleasure craft" builds that I have done, but, now I am building the BB proper as I have just recently moved to the Isle of Man and discovered that the model boat club here meet on a pond within walking distance of my house !

But, I have a few questions-

I was wondering if any of you could post some photos your own BB's - particularly the transom flap and exhaust flap details - I would like to incorporate working exhaust flaps and transom flap into my model. I am not building a fully true scale model - I have neither the skills nor time ( nor the patience ! ) to do a fully scale build - but, if it looks the part ten feet away on the water I will be happy !

 I am also looking for some Bofors for it. I have seen the Italeri kits in 1/35 scale - they seem like good value ( and appear to include the gunner and co, too ) but i have also seen some 1/32 scale guns on a website - which do you think would be the best size for the boat I am building ? The hull I am using is 35 inches x 9 1/2 inches - ( 1/32 or 1/35 scale ? )

Also, I have set three propshafts into the hull - currently set up with 30mm scale brass props and direct drive from three Speed 600 motors, running in parallel from a single ESC and single 7.2v NiMH buggy/car type battery pack of 3000mah or higher.  Now, in the past I have run this hull with a single 50mm 'X' prop and single Speed 600 ( watercooled ), running through a 2:1 reduction gearbox, single ESC and single 9.6v sub'C' type pack with no problems, a good turn of speed and about 10-15 mins duration from 1500mah pack.  The current three motor,three 30mm prop, direct drive system is quite a bit slower and much shorter duration - 7-8 mins from a 3000mah pack. I expected a drop in speed due to the change of prop type, but this is a considerably bigger drop than I was expecting, and the duration is also disappointing. My questions are, therefore -

1) is a single pack and single ESC not enough for three speed 600's on direct drive ?

2) is it the direct drive that is the issue - should I go back to having a 2:1 reduction on the motors ?

3) should I be thinking about a higher voltage - e.g 9.6v or even 12v ?

4) or should I be thinking about a twin or even single motor set-up running through a custom reduction gearbox to all three shafts ?

Any and all advice would be warmly welcomed !

All the best

Andi

[DickyD]

The Scale is 1:32 give or take a smidgin as the actual hull was 94feet. 

[Martin13]

Ahoy Shipmates !

 Newbie here with a new build Brave Borderer on a 36" fibreglass hull.

I have just started building from the Model Maker plans that were supplied with the hull. I first purchased this kit about 15 years ago and began building, then lost interest. Over the years the hull has been re-used a number of times on "pleasure craft"

But, I have a few questions-

I was wondering if any of you could post some photos your own BB's - particularly the transom flap and exhaust flap details - I would like to incorporate working exhaust flaps and transom flap into my model. I am not building a fully true scale model - I have neither the skills nor time ( nor the patience ! ) to do a fully scale build - but, if it looks the part ten feet away on the water I will be happy !

 I am also looking for some Bofors for it. I have seen the Italeri kits in 1/35 scale - they seem like good value ( and appear to include the gunner and co, too ) but i have also seen some 1/32 scale guns on a website - which do you think would be the best size for the boat I am building ? The hull I am using is 35 inches x 9 1/2 inches - ( 1/32 or 1/35 scale ? )

Any and all advice would be warmly welcomed !

All the best

Andi

Andi,

First, as DickyD stated, your model is 1:32 scale - important if you wish to buy fittings.

There are a few completed builds on this forum with pics - use the search facility - if you have no luck - pm Martin Mayhem, he knows where everything is

As this hull has been used as other models in its life and you are not going to build as true scale, forget the transom flap. If the flap is not set correctly you will lose even more power (a variation of 1 degree will effect performance), as another member found out somewhere on this forum....

Exhaust flaps - as modelers will tell you, once you put your model in the water they appear to shrink in size. Keeping that in mind, make your flaps, but not working flaps. A lot of work but will never see them.

40mm Bofors - PM Stavros re your request - you may be surprised how he can help you

Last, re your questions on electrics. Cut and paste your question and post under "Electric & All Things Black Art" the lads there will have more information than you can absorb......but they are good

And from me - great to see another member having a go at BB and looking forward to seeing pics of your build....

Hope this has been of some help

Martin doon under :) :) :)

[IainM]

Hi Andi,
Use this link to see pikkies of my 1:35 Brave boat, amongst which are the sort of shots you were looking for.
http://www.sfmbc.net/page123.html
There are also some build posts on the SFMBC.net Forum

As you'll see I opted for a single screw single rudder in the interests of weight saving.  I've got fedup with trying to make the old power to weight ratio balance and still have both a reasonable trim and realistic performance at speed.  There are a couple of shots of the boat at speed using a 9.6v MiMH 3400 pack.  So far this gives me a couple of hours of mixed running.

I'm in the process of trying to convert the Italeiri Bofors to its marine version and while its all very challenging, I'm not sure it's the best way to go.  I did have a resin cast Bofors but the resin was so brittle that it pretty much broke apart as it was being finished.

As Martin has said, the transom flap, if made adjustable, can do wonders for hull setup at speed but, if NOT adjustable can be a real drag and very significantly reduce speed.  I'd certainly fit it on any future builds I do.  You'll find some pikkies of the arrangement.

Hope this is helpful ........
Best of luck with your build.
Iain

[andi4x4]

 Hi Guys,

 Tahnks for all the advice,

 IainM - I have see some pics of your transom flap - I had planned to make mine adjustable for trimming purposes,

as for the exhaust flaps - my idea was simply to have them connected to a servo hooked up to the throttle channel so that they opened and closed in relation to the throttle setting. I may still try it yet, but, I will heed all the advice so far !

DickyD and Martin - thanks for the advice re:scale - I now know that the Italeri guns will be too small ! Will PM Stavros and see what he can do for me !


All the best,

 Andi

[Martin13]

Hi Guys,

 Tahnks for all the advice,

 IainM - I have see some pics of your transom flap - I had planned to make mine adjustable for trimming purposes,

as for the exhaust flaps - my idea was simply to have them connected to a servo hooked up to the throttle channel so that they opened and closed in relation to the throttle setting. I may still try it yet, but, I will heed all the advice so far !

DickyD and Martin - thanks for the advice re:scale - I now know that the Italeri guns will be too small ! Will PM Stavros and see what he can do for me !


All the best,

 Andi

Andi,

The main thing to remember is that this is YOUR build, build it the way you wish to, its your boat and don't forget to have fun whilst building it.

When you ask for advice from the forum, pick from it what you want and discard the rest

Check out Iain's model - he did a great job.

Looking forward to seeing your build - don't forget to add Pics on your progress....

Good luck mate

Martin down Under

[andi4x4]

Thanks Martin !

 Will send some pics when I get around to taking some - I have a new camera to try out so there is no excuse really !

Totally agree with what you are saying re: it being "my build" - as I said , I will be happy if it looks right from ten feet away on the water !

I have seen Iains boat - it is superb ! I can only aspire to such great things !

regards

Andi

[andi4x4]

Well , as promised, here are some pics of my build so far - as i mentioned earlier in the thread, this hull has had several lives, as the many layers of paint on the hull will testify to !  ::)

Original motor setup has been altered a little - the motors were originally mounted in the forward compartment and drove the propshafts via two U/J's and a length of silversteel rod. This setup produced far too much vibration, so the motors have been moved closer to the propsafts and now employ a single U/J on each without the silversteel extensions. This is much quieter, as I anticipated it would be, as there is far less vibration.

Each motor is now controlled by its own ESC and each has its own battery, the three ESC's being linkd into the throttle channel with a pair of short "Y" leads. Two of the ESC's have had the red wire removed from the plug so that the is only a single power feed to the reciever.

The center ESC is a forwards only ESC, but the other two are full forward/reverse - just happens to be what I had available at the time ! They are all rated at over 20 amps continuous, but, I havent had the chance to put a test meter across them to see what the actual draw is - I broke mine last week and havent replaced it yet  :(

These pics were taken yesterday morning - the superstructure has moved on a little since then, and will do so some more today hopefully. The hull may even get a lick of paint this afternoon  :)

Anyway - on to the pics !



By andi4x4 at 2008-04-08



By andi4x4 at 2008-04-08



By andi4x4 at 2008-04-08



By andi4x4 at 2008-04-08


I am enjoying reading the aticles others have postaed about their own BB builds in the various scales they have appeared in - they are giving me much food for thought with my own project !

Regards

Andi

 

[John W E]

Hi there Andi

Nice build so far, I wonder if I could comment on one thing.   I think you will be losing a fair amount of power due to the way that your motors have been set up.   You will be causing resistance due to the fact that your motor is not directly in line with your propeller shaft - this can be easily corrected though, just by putting packing (pieces of wedgeshaped plywood) underneath the motor mount to bring the motor shaft in line and at the same angle as your prop shafts.    This will reduce vibration and also noise and give you more power from your motor to your propeller.    If you would like to see an example of this, have a look on the 63 Whaleback build.   You can see that the motors are at the same angle as the shafts - HOPE this is of some help 

Another thing I have noticed and that is all your props are running in the same direction; now; in some cases this is correct - like the 63 foot Whaleback, however on more recent vessels - the preference was to have the two outboard propellers rotating opposite hand - one turning left hand and the other opposite one turning right hand - and the centre prop obviously turning left or right hand, whichever way.

You will see running the model with all props running the same direction you will get what is known as 'sidewalk' the boat tends to kick to one side in a straight line and also, as we have stated before it will turn in a tighter turning circle in one direction compared to the other.   It may pay you, to spend a little time experimenting with mix handed props to see if you obtain better performance.

aye
john e
bluebird

[DickyD]

Beat me to it John. Nice neat job but as you say motors could do with tilting to the same angle as the prop shafts so that they line up. Easy done though.

[Roger in France]

Yes, I agree the motors should be brought into line. I was just about to suggest it but Bluebird beat me to it.

Maybe the misalignment was caused by too much of the "Moet" in the background!

Roger in france.

[John W E]

A little picture to show the real set up of the Brave Borderer propellers; this is courtesy of a very good friend from the land of Kangaroos    you will see in the photograph that the centre and starboard prop turns clockwise and the port prop turns anti clockwise. 

Hope this is of some help.

aye
john e
bluebird

[andi4x4]

Yes, I agree the motors should be brought into line. I was just about to suggest it but Bluebird beat me to it.

Maybe the misalignment was caused by too much of the "Moet" in the background!

Roger in france.

 

Not guilty on that one ! Thank the neigbours for those - we have just moved into this house three weeks ago !

Thanks for your kind comments and advice, guys ! Obviously, I still have a lot of work to do yet, but, I hope to get out and have a "play" with her tonite !

 I have been reading about the prop issue in a number of threads on the group and plan to change that once I get the correct hand props. I had also already been considering the coupling/motor angle and plan to correct that somehow too. The alloy framework you can see in there is not fixed down yet so plenty of movement to try the shimming option.  I had just been looking at some machined alloy motor mounts that bolt the motor directly onto the shaft tubes to maintain the correct alignment ( image below courtesy of http://www.astecmodels.co.uk/ ). The guy at the local model shop also suggested some silicon tube used for the nitro exhausts slipped over the couplings would probably go a long way to dampening some of the vibration noise, too, as even when in perfect alignment the coupling can sometimes still "rattle" due to their construction. Not sure the couplings would fit into the inline motor mount when they have had a silicon sleave fitted though.





Regards

Andi

[DickyD]

Hi Andi I have a similar motor mount but  made by Graupner for my MTB and you will only need the coupling.

[John W E]

Hello

Yes, I have seen these motor mount-cum-coupling alignments gismos in the flesh and also similar to both yours Andi and Dicky and I personally hold reservations about these.   

Although they do look excellent - what makes me feel 'negative' about the use of them, is when you get a motor of a 540 size 'hanging' on the end of your propshaft, only supported by the tube, it is a fair weight and if the tube is not supported fully, I suspect it may tend to try and bend it.  Plus, the other thing is all the tork from the motor or strain if you like, is being transmitted straight onto the propeller tube.  The tork is not being dispersed via a built-in engine mount to the hull.

I suppose that if you use one of these devices you could support the motor by packing underneath it with P38 car body filler; I think that may make it more secure.

Just my thoughts - I know they are used a lot but you never see the lads and lasses with the fast boats use them.  Their motors are nearly always solidly mounted to the hull.

aye
john e
bluebird

[DickyD]

Hi John you need to fix the motor to an engine mount or bulkhead. Just use the gizmo to align the prop and motor then you dont have to worry about the torque.

[andi4x4]

Well,

 Got some more work done today - built new motor mounts to correct the drive angle - the motor shafts are now in line with the prop shafts. The hull and deck got a liberal coating of grey automotive primer - needs rubbing down now and recoating with a couple more coats of primer, then I can get on with the colours for the hull bottom and the deck, and then laquer it all in.

Does anyone have any pictures or similar of the wateling for the BB ? My plans do not show it. Also - does the red paint on the hull bottom come up to the waterline or should it be below ?

The superstructure has had a load of balsa set between the ribs which form the sides of the main cabin area and bridge and the rear section has been started. Still need to do the doorways at the front of the main cabin sides and the outer skin needs adding. This bit I am waiting for as the model shop have not had any in stock.... should be here tomorrow hopefully !

Also - took it down to the pond for a run - goes really well, quite pleased ! :) Lifts the outside prop when turning full rudder at full speed, but, it turns *really* tight ! If i flick the rudder over quick enough it will 'flick' its back end around like one of those jetboats they race in the swamps ! I May shift the link arm from the servo to reduce the rudder throw a little. I hear that 30 degrees is optimum, I haven't measured properly, but, as a guess, I would say I am probably nearer to 40 degrees with its current setting.

Seems to get up onto the plane quite easily - at least, I think it is planing - it seems to lift the front half of the hull clean out of the water and scoots along nicely.

And then it happened :

 I sunk it already !     I clipped the bank at the pond at speed and it just tipped it over onto its side  - luckily it was within arms length and I was there quickly enough to catch it before it went completely under So, it is now sitting on the workbench slowly drying out before I can do any more work to it ! 

Will post some more pics soon !

Regards,

Andi

[Roger in France]

Tough luck Andi, flipping her over like that. However, you have made great progress and little harm should have been caused thanks to your quick rescue.

Roger in France.

[andi4x4]

 Thanks Roger,

 No damage - a little warping of the removable deck has occurred, but, I think I can rescue that.

 Here's a few pics taken this evening now that everything has dried out !

Steering servo placement - this will be changed I think as I am not happy - the angle on the connecting rod does not allow equall movement each way. I do have another plan for this, so, will try it out over the next few days.


By andi4x4 at 2008-04-11



Some pics of the ongoing construction of the superstructure :-


By andi4x4 at 2008-04-11



By andi4x4 at 2008-04-11



By andi4x4 at 2008-04-11



And finally - the modified motor mounts to correct the drive angle of the couplings :-


By andi4x4 at 2008-04-11

[John W E]

hi there Andi

I have attached two photographs which I do hope show you, although they are in black/white, that the red anti-foul paint goes right the way up to the water line.   

I do not think there was ever any white plimsole line/water line painted on these vessels.  They went straight from re anti-foul paint to the grey hull paint. 

Your build is looking good - KEEP IT UP - 

One last question and this if for me, when you said the model was tight turning - was this in both directions? or, was it a tighter turn on one way only?

aye
john e
bluebird

[andi4x4]

Hi John,

 Thanks for the pics ! - I wasn't expecting there to be a plimsol line - I do not know much about shipping, but, I was under the impression that only cargo or "variable load" vessels would have had a plimsol line - I stand to be corrected on that one though !

I have a rough idea of where the red paint should come up to, but, as there are no waterline indications on the plans I have, I am also unable to judge how she is sitting in the water in respect of ballasting or weight distribution. She seems to run OK as she is - on 7.2v pack forward of the motors in the forward compartment and two behind the motors in the midship compartment where the motors are. She does seem to be planing, but also seems very "nose up" and squats the stern down a bit - I would have expected her to run a little higher and a little more level in the water. However - I have not yet built and fitted the transom flap - so I would expect that to have a significant effect on the running trim. I must get on and do that next !

As for the tight turning, she is very tight both ways - at full throttle I would say 180 degree turn in less than  three feet radius ! As I said earlier - if I give her hard full rudder rapidly she will lift the stern out of the water and "throw" it round, pivoting on the bow, jetski style !

I will try to get some running shots, or even video if I can post it here, of her in action for your thoughts !

Regards

Andi

[John W E]

Hi Andi

See if this works, this scan is from the Tamiya plastic kit instructions; each square = 5 mm on the picture. See if you can scale up to the position of the water line for yourself, on your model.  When I refer to the plimsoll line, me brain is not working yet this morning  :) would your brain work if you were being deafened by Julie Andrews singing the Sound of Music!!!  >:( :( ::)   The Mrs had that CD playing in the background!! Yikes....

Anyway, on some vessels you know you have a black line or a white line between the anti-foul and the main colour of the ship.  EEEEEEEEEEEEEE that is the line I was referring to, and I went and called it a plimsoll line. 

aye
john e
bluebird
the hills are alive ......................

[DickyD]

Nothing wrong with a horizontal plimsoll line John. 

[andi4x4]

Thanks John !

 Don't worry too much about the Julie Andrews bit - you will recover next time you put a boat on the water !

Until then - you have my deepest sympathies !   

Regards

Andi

[DickyD]

Thanks John !

 Don't worry too much about the Julie Andrews bit - you will recover next time you put a boat on the water !

Until then - you have my deepest sympathies !   

Regards

Andi

You did say the next time he puts a boat on the water ?