555 timer chip with LEDs

i'm not sure if any one will be able to help me with this. but i need to hook up 6 LEDs with a 555 timer chip so that i can get the LEDs to flash at the same time at the frequency of 3hz. the amount of power needed doesnt matter it will probably be around 18 volts.

ive been able to get 1 LED working with a 9 volt battery see site below. that flashes at 3hz.
http://www.kpsec.freeuk.com/projects/flashl.htm

all help appreciated

18v is the maximum voltage on the website, but i wouldnt expect it to last long, especially if it's used for hours at a time. i'd guess 1 year at most, maybe a few months. 15v is a safe maximum voltage, that wont significantly shorten its life.

i need to know what are the specifications of the leds u want to use. some blue ones need 3.5v 30ma, some highbrightness ones want 2.2v 50ma and some weak ones want 2v 10ma

i also need to know what exact voltage you are gonna run it off. the types of leds and the supply voltage determines if u need resistors and what values.

if you are gonna run it from a car i would either need to calculate values assuming 13.8v, so leds wont be as bright when car is off, or if headlights and/or other high power things are on. The better way to do things is to use a regulator, say 12v, that way the brightness will be consistent.

Given that you have finished the parts for making 1 LED flashes at the frequency you need. What you need to do is:
1. Take another 5 LEDs, each with its own appropriate resistor
2. parallel the whole set (LED+Resistor) to the origional LED+Resistor.

Another way is, if the input VOLTAGE IS HIGH ENOUGH, serially connect 6 LEDs which consume the same amount of CURRENT and change the resistor based on input voltage and the spec. of the LEDs.