1. In his instructable he says you can either place the vinyl on the glass first or peel it first. I would highly recommend peeling out the image first, the backing it comes on it waxed so it comes off easy, where if you apply it to the glass, it isnt difficult but a little more challenging.
2. When applying to the glass use a strip of masking tape along one edge to mount it and create a hinge, then when applying it lift up and peel from that hinge and lay down from that hinge smoothing with the credit card as you go (slowly).
3. Window cleaner or water with a little soap in it makes it so you can move it around a little, use the squeegy to squeeze out the liquid and let it sit for a couple minutes before peeling the tape off. This helps to place it and not screw up, gives you some wiggle room.
Excellent points!
1. I've done it both ways. Personally for sandblasting I'm leaning towards weeding the image after it is applied to the substrate. For every other application I always weed the image first.
2. The hinge method (which I don't outline in the instructable) I have found works best with a vertical piece of tape when used on a round glass. This lets the decal follow the curve of the glass better than if you did it horizontal. But I find the process a little overkill for a small decal the size of a glass. I use one side of the overhanging application tape to hold the image while trying to line it up.
3. I find the wet process also to be overkill for something small like this, especially something that is going to be peeled off and thrown away. If it were a car or certainly a glass window I use a wet application every time though. The spray bottle you see in the background of some of the pictures is my bottle of App Fluid. I use 8 oz of rubbing alcohol, 2 drops of dish soap, fill the rest with water and shake.
Here are some added tips:
1: If you have an uneven surface you can heat the vinyl with a heat gun or hair dryer and push it onto the shape for better adhesion. I use a tennis ball to work the vinyl over things like rivets in box truck body panels or even on to painted brick walls.
2: A small pancake air compressor probably does not have enough CFM or air volume to keep up with a sandblaster. Mine is a 3hp 20 Gallon unit that outputs about 12cfm and it can't keep up for big jobs.
3: Dedicated pressure blasters or hopper fed blasters work better than the siphon blaster I use.
4: Sand gets EVERYWHERE unless you have a cabinet. Do it outside and cover your body as much as possible.
5: Don't use the thin slinky style hoses. Use as wide a diameter hose that you can get your hands on.
All that said it is a lot of fun and certainly anyone could do it at home without any major issues.