Flashing 12V incandescant lights

Can incandescant lights be flashed with an arduino? They need heat to illuminate so im not sure if flashing can work? I'm trying to control my model train crossing lights via arduino and they are 12V incandescant lamps

Totally doable. You'd need some transistors or relays to switch the 12V since arduino can only deal with up to 5V.

Even if I'm using a separate power supply for the lights and not powering them from the board itself?

Yes

How much current do they need?
There are open drain shift registers that can sink 100mA, 150mA, 350mA, above that you should be looking at individual transistors.
I have a board with up to 96 150mA outputs, and another with 32 1A outputs (both current sinking) if you're interested:
http://www.crossroadsfencing.com/BobuinoRev17/

Ill test and see what they draw.

They draw .16 amps. Im not sure I need a board with 96 outputs though. Anything smaller?

Something like this: http://www.ebay.com/itm/Four-Channel-4-Route-MOSFET-Button-IRF540-V2-0-MOSFET-Switch-Module-For-Arduino-/161420103429?hash=item2595634f05:g:8pAAAOSw-jhUEscW

aarg...is that any different from a normal 4 channel octo coupler relay? I have a bunch of them lying around

dinotom:
aarg...is that any different from a normal 4 channel octo coupler relay? I have a bunch of them lying around

Sure you could use a relay, why not? If the clicking doesn't bother you. It's "opto", not "octo".

typo, weird keyboard lately. ill work on it that way

I have the 12v lights flashing as intended, and aarg was right the constant clicking of the mechanical relays does disrupt the intended result since its for a model railroad crossing signal and the sound disrupts the crossing gates bell sounds. The On Semiconductor website says the IRF540 is obsolete? Is their a newer mosfet relay I should be working with?

IRLZ44N
FQP30N06L
IRLB3034PbF
AOD514/AOI514/AOY514