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[martno1fan]

Hi i run big petrol powered boats as a few of you might know and ive been thinking of building a springer from the plans available as a resue boat to push my big boats in if and when they stall or flip upside down which can happen at 60 mph  .I will first make a wooden plug and then make a mould and build a glass fibre one.I have a good high tork motor from a  tug rated at 6-12 volts i got on ebay that ill use for it powered by a dry cell 12 v battery,or would i be best using 8.4 volt nimmh cells.Any input on my idea would be appreciated thanks
Mart

ps When im done id like to also offer a few mouldings for sale to enyone interested if anyones interested let me know,i can also produce a glass deck if needed.

Title renamed - Martin.

[toesupwa]

.... i'ive been thinking of building a springer from the plans available as a resue boat to push my big boats in if and when they stall or flip upside down. I will first make a wooden plug and then make a mould and build a glass fibre one.I have a good high tork motor from a  tug rated at 6-12 volts i got on ebay that ill use for it powered by a dry cell 12 v battery,or would i be best using 8.4 volt nimmh cells.Any input on my idea would be appreciated thanks

Contact Norry, he already makes GF Springer hulls.

Go with two 6v 4.5ah batteries.. gives long run times and makes for good ballast 

[martno1fan]

Hi i dont want to buy what i can make myself no disrespect to him or anyone,i allready make my own mouldings so i may as well add a springer to the list  .Thanks for the info on the batterys but i allready have a dry cell 12 volt battery from a big rc car its not too heavy just about right id say so ill give it a go.What size prop would you suggest?.
Mart

offer still stands anyone wanting a moulding let me know

[tigertiger]

Hi Martno1fan

When you get to the stage where you have a finished product that you are able to sell, you can list this under the traders section.

Regards
Mark

[martno1fan]

Cheers mate im aware of that but cheers anyway 

[Martin (Admin)]

No limit on prop size, whatever suit your motor best.

http://www.modelboatmayhem.co.uk/forum/index.php?topic=3471.msg49453#msg49453

[martno1fan]

Thats why i asked as im not sure what prop to use,its a high torque motor so i asume a big prop would be best.Im more used to fast boats, i think the slowest one ive run is a pt boat and thats pretty fast.Not including my sailboat that is  .
Mart

[tigertiger]

Hi Mart

What do you want from your boat. Speed or push. I assume push as it will be a rescue boat, you may get more push from a 3 prop motor. The other thing that may need to be considered is heat generated when the motor is 'working', so the max prop may not be the bbest solution.

I don't know the answer, but having posed the questions I am sure someone will come back to ansewer.

[Martin (Admin)]

For a "standard" 540, 550, speed 600 type motor, you should be OK on a 3 bladed 35 or 40mm props.

[toesupwa]

Thanks for the info on the batterys but i allready have a dry cell 12 volt battery from a big rc car its not too heavy just about right id say so ill give it a go.
What size prop would you suggest?.

If the battery weighs in at about 3lb you should be ok... although where you will put it in a Springer hull may be a problem once the motor is fitted.
What motor do you have?.. a 'standard' RC car motor drives the 35 - 40mm prop with ease and makes a Springer twitchy on the throttle.
If its a High torque motor (such as a Pittman) then the prop you use is up to you.... I've even managed a 3 3/4" prop on a Springer (Mustang Sally) but thats WAAAAAAY too much power..

[martno1fan]

Thanks guys im not sure what size the motor is all i know is its rated at 12 volts and its high torque and came out of a tug,guy said it was very strong.ill post a pic later maybe you guys can identify it,thanks for the help.Oh yea the battery i have weighs in at about 2-3 lb ill weigh it later to be sure.I cant remember the mah if its not high i might go with two 6v ones wheres best to buy those from maplins maybe?.
Mart

[toesupwa]

... i might go with two 6v ones wheres best to buy those from maplins maybe?.

http://www.component-shop.co.uk/html/lead-acid.html

[Arrow5]

Dang it Toes ! wasted time typing that in just to see the red warning. Yep Component Shop and/or Maplins. Looked at another named source that I found in the municipal skip (6v 4ah charged it ,tested and fine) which has the brand name www.nightsearcher.com, might be worth a look.

[martno1fan]

Cheers fellas another question ive been reading these tugs have issues with water lapping over the deck and some guys have added splash protectors on the deck etc i was thinking i could make the sides 1" higher and set the deck 1" lower and cut a few drain holes in the sides for any water that does get on there also im thinking of raising the bow a bit and maybe even adding a stem and small keel to help disperews water a bit better what do you think? im not talking much maybe 1/2" and tapered to a round edge like ona barge or similar.Ill post apic of what i mean later.
Mart

[martno1fan]

heres a crude pic of why i mean maybe i dont need the keel bit but im thinking the stem bit might help disperse some water?.

[Arrow5]

Yes a raised stem is a good idea, all of mine have a higher bow than deck level, a sort of dam.  If you mean spray strips along the front edges I dont think that is so good, better to have the edges of the hull rounded to let the bow-wave escape round the sides. I have a piece of 90 degree angle between the knees on the Sprub as she is very low in the water. It seems to help stop water climbing up and over the bow. Drainage ports on any "wall" round the deck is essential and at the transom. Trimming with battery position to a couple of notches up at the bow helps.

[martno1fan]

hi no i didnt mean spray rails i just mean ill put a pice of trriangular stock at the stem verticaly to maybe help water disperse a tad and ive allready rounded the front corners,the plug is almost done just need the bottom sheeting now,im using some plastic sheeting as its easy to bend and its only for a plug anyways.Should have finnished mould tomorrow night,cpl of new hulls by the weekend all been well.Ill take a few pics and post them as i go.

[martno1fan]

Heres where im at at the moment i will of course need to spread some filler onto the edges of the chipboard ,its all i had but it will do the job for a plug once sanded smooth.The face is smooth enough as its pretty dense stuff not like some cheap board you get.
Mart

[Arrow5]

Yep that looks OK. Central beam might be at odds with the two push-knees that are more common. I think I`d leave the bulwark square cut and allow folk to customise to suit their chosen top design.  The bottom of the knees should be above the waterline to allow some sideways flow. On the Sprub pic below you can see the build-up of bow-wave is contained by the horizontal strip between the knees. On the orange one the tyres do the same.  Any idea what yours is going to look like topside ?

[martno1fan]

Yea you could be right i might remove it and leave it as was then people can  decide what to do from there,as for mine up top i havent decided yet but something fun as my son will be the one driving it mostly  .As for the rest ill leave it as is because should anyone want to change the bullwark they can trim the glass back to where they want it with a dremmel or a hacksaw blade.Ive built this so i can set the deck 1" down from the top edge all that needs doing is some bearers epoxying to the hull inside.
Mart

[Arrow5]

Check your PMs.  Yes I think the ideas that have emerged in  Springer mania it would be better just the basic hull shape. I see your avatar, how about this for a top ::)

[martno1fan]

Haha thats an idea 

[tigertiger]

Hi Martno1fan
I think that if you are going to do a hull moulding, that you intend to sell, it will need to be 'regualtion' Springer design.
And the rest, as you say, is up to the builders themselves.
If not regualtion you need to state this in any advert, and this will affect sales.

Just my thoughts.

[martno1fan]

So your saying keep it as per the plans? but i think the plans could do with changes? i dont think the higher sides will effect sales as if they dont want a water barrier they can soon trim it back.I can easyly offer either design its no big deal but thanks for the tip.What do you call regulation? are there any rules stating how big these things have to be if so can you point me in the right direction
Mart
ps this is only the start expect lots more designs

[Martin (Admin)]

The guidelines for "Springers" are now fixed and we are all building to those.
Of course anyone can build anything they want but unless it conforms to the fixed springer guidelines, it's not
a Springer, it's just something else.... Sringerish, Lookie likeie, Super Springer etc.
It's the same for any rules of "class" type racing.

http://www.modelboatmayhem.co.uk/forum/index.php?topic=10759.msg100987#msg100987