is there and reason I cant cover a resistor with a heat shrink tube
You can do anything you want! I assume you are using axial leaded resistors and not surface mount, but who knows. For sure, anytime you cover a resistor you reduce it's ability to dissipate heat.
Paul
Yeah, covering resistors with heatshrink tube is fine, I do it routinely. Just don't do it on a resistor that gets hot during normal operation.
I've done it with a resistor soldered to an LED many times. I usually like to use clear heatshrink so I don't forget about the resistor if I ever have to troubleshoot in the future.
If you look at 12V LEDs on e-bay, you can see a heat-shrink lump near one LED leg, that is a current limit resistor.
Ok this is on a 10k resistor so not much heat, thank you for the feed back