I just put some on my carbon arrows. They work great. Like 4cslabs said have a tall enough glass so the entire thing goes under water at the same time. I used a Mason jar. Another trick is I ran my real hot tap water into the jar until I was ready to pour the boiling water into it. That way you don't lose any heat with a cold jar. Dump the tap water and pour boiling water into it immediately then stick arrow shaft into it. You absolutely don't have to put arrow into boiling water as it is boiling in a pot.
No more fletching for me. They are great!!!!