I think the Global iron is carried by Hobby People as well.

Good idea about the thermometer too. Different coverings have different tack and shrink temps, and going at a covering with the iron full throttle could be a mistake and ruin it, or shrink it beyond what you need, which can eliminate the possibility of future touch up shrinking.

Aerohead also has a good point I will add to. When first considering shrinking the covering on any plane, go over all the edges with your iron to make sure they are well stuck before attempting the large area shrink with the gun. Often they are not as tacked as they should be from the factory. Although this is not a 100% prevention for pulling the edges loose on close lapped seams and leaving a gap, it will help a great deal.

The "flutter" sound you heard is common when using a gun and the covering is loose, and not an indication of burning through.

Oh, did anyone mention to keep the gun moving? As birdnest pointed out about using the iron AROUND the wrinkle, also use the gun AROUND the wrinkle first, as this will often eliminate the wrinkle without even focusing on the wrinkle. Keep it moving to heat the covering as evenly as possible. This way if one spot has run out of "shrink" capability due to overheating, such as a bad wrinkle, it's possible the covering around it will pull it tight.

Good luck with it, and let us know how you fare.

Dave