Model Boat Mayhem

The Shipyard ( Dry Dock ): Builds & Questions => Springer Tugs => Topic started by: dave parker on January 13, 2020, 09:36:19 AM

Title: 6v battery for springer
Post by: dave parker on January 13, 2020, 09:36:19 AM
Hi all

Can anyone recommend 6v sealed re chargeable batteries for use in my first springer tug, and where best to get them from in uk?

it is designed to have 2, one each side, and will probably need to be laid on their side

Thanks
Title: Re: 6v battery for springer
Post by: Taranis on January 13, 2020, 10:14:29 AM
Size weight and shape are important variables. Too big it won't fit too heavy you'll push it below the water line.
You need to be able to copy someone elses design to benefit from their experience or be in a position to bath test it and see how much ballast it needs.


Component shop stock a very good range of sealed Pb batteries
https://www.componentshop.co.uk/batteries/lead-acid.html
Title: Re: 6v battery for springer
Post by: dave parker on January 13, 2020, 10:39:54 AM
Thankyou
Yes I found component shop and wondered if they were the best place
I thinking of standard 6v spa and have seen 2ah and 4ah
Title: Re: 6v battery for springer
Post by: Colin Bishop on January 13, 2020, 12:00:27 PM
Bear in mind that the usable capacity of a SLA battery is around half the nominal capacity. You would probably be better off using NiMH batteries which will give you twice as much running time for around the same weight or less.

Colin
Title: Re: 6v battery for springer
Post by: SailorGreg on January 13, 2020, 01:34:32 PM
I would second Component Shop.  I use one of these  (https://www.componentshop.co.uk/6v-7-0ah-sealed-lead-acid-battery.html)in my Springer.  I find it gives plenty of running time and is just the right weight to ballast the hull down to a suitable waterline.  I have no additional ballast in mine, although all Springers vary depending on how (and of what) they are built.  Of course, you should check the dimensions and make sure you can get it in and out of your hull fairly easily.


Greg
Title: Re: 6v battery for springer
Post by: DaveM on January 13, 2020, 01:43:45 PM
I too have one of those. It makes a fine doorstop and is also occasionally used to weight thing down flat while glue dries.  ;D
DM
Title: Re: 6v battery for springer
Post by: SailorGreg on January 13, 2020, 01:57:41 PM
A very versatile battery!  Although just noticed it is out of stock at Component Shop, so maybe others are holding their doors open with one.   {-)

Greg
Title: Re: 6v battery for springer
Post by: Gardener on January 13, 2020, 02:06:12 PM
https://www.componentshop.co.uk/7-2v-5000mah-sc-nimh-battery-pack.html (https://www.componentshop.co.uk/7-2v-5000mah-sc-nimh-battery-pack.html)


use one of these 7.2v batteries in my springer
Title: Re: 6v battery for springer
Post by: Gardener on January 13, 2020, 02:14:23 PM
https://www.componentshop.co.uk/6v-5000mah-sc-nimh-battery-pack-5-x-1.html?___SID=U (https://www.componentshop.co.uk/6v-5000mah-sc-nimh-battery-pack-5-x-1.html?___SID=U)
6 volt equivalent
do you need as low as 6v would 7.2v be better for powering motor ?
Title: Re: 6v battery for springer
Post by: dave parker on January 13, 2020, 02:30:08 PM
I am open to suggestions
7.2v would give a little more power so in theory would be fine!
My design works on having two in the boat, one each side
With it being my first build and I am using other peoples as examples, it seems most common to have 2 ska batteries...
Title: Re: 6v battery for springer
Post by: SailorGreg on January 13, 2020, 02:38:02 PM
I think the reason many go for SLA is that Springers need a fair bit of ballasting.  A SLA gives that while a NiMH pack, which is fine for generating power, is a bit lightweight (literally!) and you would need some lead to get the boat to sit properly. Your choice, neither is wrong.

Greg
Title: Re: 6v battery for springer
Post by: dave parker on January 13, 2020, 03:09:33 PM
Yeah my thoughts too
And sla are cheaper too
Title: Re: 6v battery for springer
Post by: drawknife on January 13, 2020, 04:21:23 PM
I have a 7.2v NiMH and about 2.5 lbs of lead as ballast. Easy to position the lead to get the correct waterline.
Title: Re: 6v battery for springer
Post by: Netleyned on January 13, 2020, 04:40:11 PM
2x6v 4amp SLA's will do the job as long running and ballast. More volts, more speed and more nose diving as Springers are prone to.
Place the batteries far enough aft to give the Springer a slight bows up set. Be sparing on the throttle stick or you will have a submarine.
Title: Re: 6v battery for springer
Post by: dave parker on January 13, 2020, 04:48:35 PM
Brilliant thanks Ned!
 :-)) :-))
Title: Re: 6v battery for springer
Post by: radiojoe on January 18, 2020, 11:20:11 AM

Hi Dave,  I used two 12 volt sla batteries in Gopha Girl  They are 90mm X 60mm X40mm  they run for hours and she still needed a fair amount of lead ballast,  I used two 6 volt sla batteries in Gala Girl they are 95mm X60mm X25mm. Plus a lot of lead ballast not sure of the performance of these as I've only tested her in the bath, must get around to testing her down the lake one day, the only reason I used the 6 volt ones is because I had them spare at the time of building her, If I were to use the springer a lot I would defo change them and the motor to 12 volt, a lot of power and run time here's a pic of the 12 volt ones.


Joe