Model Boat Mayhem

Dry Dock / Shipyard: Builds & Questions => Pleasure boats, Sports, Race, Power and Leisure Boats: => Topic started by: Biscuit on March 17, 2013, 08:04:48 PM

Title: Touchwood K7 Bluebird again
Post by: Biscuit on March 17, 2013, 08:04:48 PM
Well dug this out again, had to buy some new cells as others had died for some reason, thought I would just stick all the gear back in it tape it all down and see what happens. It weighs a ton so thought it would never float but filled paddling pool up and it looks like its sitting about right, the only thing that I think is wrong is the prop size it looks so small, its around 32 mm ish diameter 3 blade, Im running a 2800kv motor on 3 cells so should give me around 30,000 Rpm, so what you think I should be running prop size?
Thanks
Title: Re: Touchwood K7 Bluebird again
Post by: Tugtower on March 17, 2013, 08:14:51 PM
X40 2 blade since its a power boat maybe an x45 depending on the motor size and if it can fit. to put it in some perspective, the fast electric i own runs an leopard 4050 (40,000 rpm) brushless motor 3c, running and x40 prop and can take an x45 easy boat is 26" long. if u want fast you go 2 blade  :-))
Title: Re: Touchwood K7 Bluebird again
Post by: Biscuit on March 17, 2013, 11:10:02 PM
Like I said 2800kv on a 3cell not a power boat it's a hydro thanks.
Title: Re: Touchwood K7 Bluebird again
Post by: Biscuit on March 23, 2013, 12:55:03 AM
Well never mind, will go it alone, thanks anyway, what happend to this site, must of been away to long lol :-)
Title: Re: Touchwood K7 Bluebird again
Post by: Tugtower on March 25, 2013, 12:54:07 PM
Probably the reason you never got anymore answers is that regardless if its a hydro/powerboat or w/e is that the advice given on the prop is right, on scale boats you cant always have a scale prop so you use the next best thing and in this case an X40 or x45 would be ideal.


However.. that being said you could look at the hydro props http://www.westbourne-model.co.uk/acatalog/Graupner_Model_Boat_Propellers_.html (http://www.westbourne-model.co.uk/acatalog/Graupner_Model_Boat_Propellers_.html)


but an x40 or 45 would still do the job just as well.
Title: Re: Touchwood K7 Bluebird again
Post by: Mad_Mike on March 25, 2013, 02:17:32 PM
Biscuit this forum isnt probably the best place for the fast stuff. Its more on the scale side. However there are a small handful of us that dabble in the fast lane. I'm afraid to say that tugtower has given you what i would regard as the best answer given the information. The motor size aswell as the kv also plays a part to what size propeller to use.  Anyway would it matter if the prop doesnt look scale? the k7 is jet powered anyway.
Title: Re: Touchwood K7 Bluebird again
Post by: soundcheque on March 25, 2013, 08:02:17 PM
Well dug this out again, had to buy some new cells as others had died for some reason, thought I would just stick all the gear back in it tape it all down and see what happens. It weighs a ton so thought it would never float but filled paddling pool up and it looks like its sitting about right, the only thing that I think is wrong is the prop size it looks so small, its around 32 mm ish diameter 3 blade, Im running a 2800kv motor on 3 cells so should give me around 30,000 Rpm, so what you think I should be running prop size?
Thanks
Hi Biscuit,,
I'm currently building this exact same model for a customer..
It's a heavy bit of kit and I've had to carry out some mods to lighten it up and also replace most of the resin parts with balsa which are then skinned with styrene..
There is some good info on this forum which I mostly contribute.
http://www.rcgroups.com/forums/showthread.php?t=1383262 (http://www.rcgroups.com/forums/showthread.php?t=1383262)
I also have a page on Face book which you may find usefull
http://www.facebook.com/TheModelBuilder?ref=hl (http://www.facebook.com/TheModelBuilder?ref=hl)
I'm actually going to try ducted fan on this one as I had good results with the 1/24 scale and a 30mm fan unit.
Title: Re: Touchwood K7 Bluebird again
Post by: Biscuit on March 25, 2013, 08:25:45 PM
Yeah I know my boat build is on there with the alloy planning wedges, had boat for nearly 5 years, I came real close to finishing it last time but then got fed up with it, think thats why the brand new lipos died just sitting there for the last 18 months or so.
Steve Bisco
   
Title: Re: Touchwood K7 Bluebird again
Post by: soundcheque on March 25, 2013, 08:48:02 PM
Oh that's cool.. Well done
All the best with it.. I guess I'll post my results here too.
I'm very sceptical about the choice of power as it may well not work but I'm looking forward to the challenge with the newer technology in lipo performance and fan units..
Title: Re: Touchwood K7 Bluebird again
Post by: Biscuit on March 25, 2013, 09:10:19 PM
Good luck with that, keep us posted, I have a number of props now new cells and it sits in the water nice, just glued some foam in the top cowling so ready to go, I also have over 8mm of movement on the strut up and down, I would guess you will have to give it a big handfull of power to get it up. I remember as a kid sitting and watching the real one go over and never forgot it, been to Coniston water a number of times its a special place.
Title: Re: Touchwood K7 Bluebird again
Post by: Biscuit on April 13, 2013, 08:33:03 PM
Well took my Touchwood Bluebird out for its first test run yesterday, I got to say for its first run out of the box I was very pleased, I did lift the prop 5mm, runs on rails and there is more speed to come as it took hardly anything out of the cells so can go up on the prop. This is a little vid done on my phone on a grey day with a grey boat in primer so not great but what a start  :-)
 
http://www.youtube.com/watch?v=Xv6cklsfYcg (http://www.youtube.com/watch?v=Xv6cklsfYcg)
Title: Re: Touchwood K7 Bluebird again
Post by: davidjt on April 13, 2013, 08:46:12 PM
hi
 
what a fantastic speed that has %% %% %% , can i ask you what motors and prop you have put in, i built this 3 years ago from scratch, plank on frame, and gave up as well like you. as all the motors i tryed were slow to useless so just use it like a run about.
 
david
Title: Re: Touchwood K7 Bluebird again
Post by: Biscuit on April 13, 2013, 09:14:05 PM
Well this was a Touchwood static kit that I converted to r/c, it has a 2700kv motor runing on 4200mah 11.1v 3cell lipo, through an ETTI 150 amp esc to a 32mm 3 blade hydro prop.
Title: Re: Touchwood K7 Bluebird again
Post by: davidjt on April 14, 2013, 10:28:57 AM
hi biscuit,
 
can you tell me the size of the can thats what i call them on (brushed) or the diameter from drive shaft to outer case, i bought one brushless and found out it was 25mm x 25mm without shaft  and looks lost, but told i need someting bigger in diam?, any advice welcome
 
david
Title: Re: Touchwood K7 Bluebird again
Post by: Biscuit on April 15, 2013, 11:30:05 AM
Hi, motor is 27dia by 55mm long.
Title: Re: Touchwood K7 Bluebird again
Post by: essex2visuvesi on April 15, 2013, 11:45:38 AM

I'm actually going to try ducted fan on this one as I had good results with the 1/24 scale and a 30mm fan unit.


I'd be interested to see your results with the edf
Title: Re: Touchwood K7 Bluebird again
Post by: Biscuit on April 19, 2013, 10:59:21 AM
Well got some paint on at last, it looks a bit light in the pics but in real light its the perfect colour :-)
Title: Re: Touchwood K7 Bluebird again
Post by: Biscuit on April 19, 2013, 11:03:43 AM
This is more the real colour :-)
Title: Re: Touchwood K7 Bluebird again
Post by: Tug-Kenny on April 19, 2013, 11:42:02 AM
They look very similar.

Do you want one removed  ?

Ken

Title: Re: Touchwood K7 Bluebird again
Post by: Biscuit on April 19, 2013, 12:00:32 PM
Yeah dont know what happened there {:-{
Title: Re: Touchwood K7 Bluebird again
Post by: Biscuit on April 19, 2013, 12:01:26 PM
Yes thanks
Title: Re: Touchwood K7 Bluebird again
Post by: essex2visuvesi on April 19, 2013, 12:11:25 PM
Are those Kyosho RC motorbikes I can see in the background?
Title: Re: Touchwood K7 Bluebird again
Post by: Biscuit on April 19, 2013, 11:02:12 PM
No they are 1/5 scales. I do have a few Kyoshos.