Our Springers

First my wifes boat and then my big springer

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Here are my two Springers, Lady Laura and Woody

i just love the hundreds of variations that you see of the springer......

if it weren't for these variations i don't suppose it would have the same appeal that it does, but boy oh boy, there are some that REALLY make me smile and brighten my day....little things like the toy story woodie on yours alan....just brilliant imagination.....sadly something i don't possess....if it ain't on the plans, i'm stuffed, and i really do admire that imaginative trait in you springer builders..

Thats the good thing about about springers Neil,the tops of them are endless.
Your building qualities are superb,so maybe we will see a RNLI springer
Mark

well, it's definately a thought...was wondering if i ever got round to one, what i could do one as.

what i didn't realise was that they are modelled on the base of real vessels that have the hull shape....i always thought that they were originally a figment of someones imagination.
how wrong can i be.
cheers.

neil

Easy,
Build a basic hull,then put one of great ribs that you made on top,bucket by pondside,
hopefully public will give to a worthy cause

HA HA HAAA! Still waiting to see that springer on the plane!!!

Don't have enough space for a full springer, so made this one at 66% size.
Runs a 240 motor, SAB plastic prop and brass tube, on 7.2v rechargable NiMH, 2.4Ghz control.
https://i.servimg.com/u/f46/17/36/24/73/scruff12.jpg
https://i.servimg.com/u/f46/17/36/24/73/scruff13.jpg
https://i.servimg.com/u/f46/17/36/24/73/scruff14.jpg

video here

https://www.youtube.com/watch?v=d3PZENXBFpQ

All balsa, and will be my rescue boat for my other boats I'm building

vnkiwi

Very nice. Do you plan to have pushers on the bow ?


ken

a bonny little model.............you could almost put it in your pocket.....

neil.

Cute



Alan

Not at this stage Ken. Most of my boats are less than 24inches long and its fitted with a floating ball and line, (not attached in the video) so its mostly circle and tow back. But it does have a continuous soft rubber bumper all round.
May fit one later if I think its required
Here is a video link of the size boats I have at the moment

https://www.youtube.com/watch?v=QOHhgG6Ay3A

This is my 12" Fairey Swordsman, Both boats have the same power train and r/c, except that the swordsman runs 4.8v NiMH rechargeables (weight is critical)
cheers
kiwi

I tried to post this before so i will try again. I was asked to help with the springer tug that my brothers and mate are and have built.
so one brother Roy wanted to use a shottle drive so need some help
so
Graupner Schottel Drive Unit I (1761) then motors choice


MFA Torpedo 800 with Belt Drive Unit

MFA950D 385 Geared Motors
Krick Max Gear 540 Type Motor 2.5:1

so I worked out a way to do some more calculations and could be used on any model I think I have been mainly working stuff out for real boats so made an adaption
Model boat speed/ pitch/rpm calculations
 
First change all to meters   and seconds
 
RPM = RPS    Speed MPH to   m/s  pitch inches or cm or mm to metres
 
V= speed wanted or known
 
RPS
 
P pitch into meter
 
V=  P/RPS        P = V/RPS     RPS = V/P 
 
Example   tug
Prop RPM   = 560    
 
P x 2.89” = per rev = 2.89X 60 = 173.4”  = 4.38m 
 
V = 9.33 /4.38  = 2.13m/s    = 7.66kph or 4.76mph
Losses approx. 26%  would then give 4.76 – 1.23 = 3.53mph
 
The thrust ?
 
 
Dwlbs  Springer tug 1.5kg = 3.31lb
 
So I make it
 
3.31lb will displace .0015m3  in fresh water or .05297cub ft
 
To move it at 3.576 m/s or 8mph
 
You will need  52.6 N  or 11.82lb-force
 
At 1.788m/s or 4 mph
 
You will need 26.3N or 5.9lbs- force
 
This will help   https://www.omnicalculator.com/physics/buoyancy#buoyant-force-equation
 
Loss about 5%  about 7.6 mph   or 3.8mphjust thought it may be interesting to you