Help lighting a Viper Mk II

[roflmaoist]

Hello everyone!

I'm new here at the SMA forums and I've just gotten back into model making after quite a long hiatus (about 10 years!). I've just started a new build - Moebius' BSG Viper Mk. II and have decided that i'd really like to light it up. I've been to the local pound store (I'm in the UK) and bought a couple of really cheap gadgets with LEDs along with wires and a switch.

My question is: How should I get power into this thing? I've trawled the internet and found very little about how to actually get power into kits like this. I can't decide if I should fit everything inside the viper itself (but then what happens when the batteries run out??) or whether to somehow have the power fed into the viper from a power source in the base.

My main concern about having the batteries inside the fuselage is that at some point the batteries will die and then it'll be a nightmare to replace them.

The problem with having the power source in the base is that I don't want the viper to be permanently fixed/wired to a stand.

Could I use rechargeable batteries in the viper??
Does anyone have any suggestions for a total lighting No0b?

Thanks guys. I'll post some images of the viper as it progresses...

Roflmaoist

 

[Grendels]

I would put the batteries in the base of the model. You can use many different methods to get power from the base to the model itself. One is to use a DC power jack.

If you locate it in the center of balance, you can put the female part of the jack in a brass rod, so that the model is balanced on the jack.

This way the model is removable from the base and you don't have batteries in the model.

A good example can be found here:

http://www.scalemodeladdict.com/index.php/topic,198.0.html

 

[roflmaoist]

Hi Grendels,

thanks so much for your advice! I've had a look at the post and had a go at stripping out a 3.5mm male-female audio cable - i thought i might be able to use the female end in the model and the male in the stand. So far though, i've not been able to get a current to pass through the connection. I'm probably doing something wrong but I'm not sure what...

You suggested using a DC power jack. What is that exactly? I've got a bunch of power cables for charging up devices (old laptops, electric shavers, phones etc.) but they only have the male connector. Where would I get the female connector?

Thanks for your help! Sorry to be so clueless - this is the only part of the lighting process that I can't figure out.

Roflmaoist

 

[Grendels]

Radioshack carries quite a few different ones.

Here is one I commonly use:

http://www.radioshack.com/product/index.jsp?productId=2102489

As you can see, it has a nut on the end and will allow a pretty good hold on the model.

 

[roflmaoist]

Aha! Right I've bought one of those and I've decided to put the female connector in the aft section between the rear landing gear where there's space for the wires etc. I'm trying to decide if I'm going to model the viper as on the deck or in flight. On the deck makes connecting the electronics easier but I'll have to make sure there are no light-leaks from the undercarriage. In flight is more complicated as i have to use a rod to balance the ship on.

One last question: I'm going to connect 6 LEDs to three AA batteries at 1.5 volts each. Do you think that using resistors is necessary? I'm not sure if three AAs is going to be enough to get decent brightness out of the bulbs. Need to think about that one. Sorry - you probably get this kind of question a lot on these forums!

Thanks for the help Grendels. I'm really excited to get going on this!

 

[Grendels]

If you use three AA batteries, you will need resistors. But if you use two AA batteries you will not. Well I need to clarify that a bit.

If you use blue, green or white LED's only then you will not need resistors with two AA batteries. But if you use Yellow or Red LED"s then you will need resistors no matter what.

One way around this is to paint white LED's the color you want with transparent paint. I have done this before and it will work.

Two AA batteries will power 10 LED's for 40 to 50 hours, so no worries there. I put 5 LED's in my viper three years ago, and they still light up the engines when I turn the switch.

 

[roflmaoist]

Thanks for this! I've been away for a few days so haven't been able to respond. Basically, I'm only using one mini red led which I've harvested from a fibre optic lamp. It's already fixed to a flashing circuit board and is designed to run off three AA batteries. It's connected to a green and a blue so I'm guessing that a resistor won't be necessary...

I'm also going to be using some white leds in parallel - they have all been harvested from devices in which they are connected individually and without resistors to batteries totalling 6v, so I'm guessing I'll be ok with those too.

I'm going to post some photos of my progress with an explanation of the power source solution you described just to help anyone else who's starting out with this stuff. I'm hoping I'll get more some useful hints and tips from that!

Thanks for the help Grendels!

 

[Grendels]

If you have removed the LED's from their circuits, they will need resistors. But if you kept them on the board they will not.

I have not had time to look at the post, but I will in three or four days.