This seems to come up often enough that I thought I'd document how I did mine. The pictures I have are all of my set of 16s, but it is the same process whether you are building 15s, 16s, 16.5s, or 17s. I used 16x7 steel wheels. The beadlocks add about an inch or so to the width of the wheel, so I ended up with 16x8 beadlock wheels.
The first thing you need to do is determine which side of your wheels you need to put the beadlock rings on. This may sound stupid, but let me explain. On the inside of the wheels is a "dished out" area that is used to allow the tire enough room to stretch over the bead when mounting. The dished out area is positioned to one side on the wheel. It is nearly always off-set to the outside facing surface of the wheel. However, on wheels with extremely little backspacing (2" or less) the wheel may be reversed and the dished out area may be towards the inside surface of the wheel. The beadlock rings have to go on the side closest to the dished out area of the wheel. If you put them on the other side you will not be able to get a tire onto the wheel. This means that on some wheels the beadlock will be on the inside of the wheel, by the brakes. If this is not your desired result you may not have wheels that are suitable for making into beadlocks.
The next step is to take a grinder or wire wheel and clean all the paint, rust, and grime off the lip of the wheel that you will be welding to. This picture shows the area that needs to be cleaned, and it also shows the offset "dished out" area that I talked about earlier.
Once you've got the lip all cleaned up go grab one of your beadlock rings. Take a look at the edges of the ring. The edges on one side will be sharp and square. The edges on the other side will be slightly smoother and rounder. You want the shoother edges to be in contact with the tires, so lay the side with the sharp edges down on your wheel. Feel all the way around the ring and move it until it looks and feels like it is perfectly centered on the wheel. You also want to rotate the ring so that the valve stem of the wheel is in the middle of two bolt holes. You don't want to have one of your beadlock bolts interfering with your valve stem. Here's a picture of what you should have at this point.
Now that the ring is positioned where you want it, go ahead and tack-weld it into place in about four spots around the wheel.
Now find a comfortable spot to sit, and start welding. This weld needs to be pretty close to air-tight, so a quality weld is important. Most of the leaks come from where the welds start and stop, so two welds overlap. I try to make as few welding passes as possible. I can usually weld all the way around the perimeter of the wheel in four or five different sections. Some people say you should weld in many smaller sections to avoid heating up the wheel too much and warping it. That is good advice on many other projects, but I don't think there is any way you are going to warp your wheel, so to minimize the possibility of leaks I weld in as few different sections as possible.
This next step is something that some people do, and some people don't. After all the rings are welded up I like to grind down the welds a bit. This knocks off all the high spots and rough spots that make the tire harder to mount. Remember, when you go to mount your tires on these wheels the inside tire bead has to slide over this weld.
Next step is painting, and you already know how to do that... For the best results spray the bare metal with a primer before you spray your color. This will help the paint stick and last longer.
The first thing you need to do is determine which side of your wheels you need to put the beadlock rings on. This may sound stupid, but let me explain. On the inside of the wheels is a "dished out" area that is used to allow the tire enough room to stretch over the bead when mounting. The dished out area is positioned to one side on the wheel. It is nearly always off-set to the outside facing surface of the wheel. However, on wheels with extremely little backspacing (2" or less) the wheel may be reversed and the dished out area may be towards the inside surface of the wheel. The beadlock rings have to go on the side closest to the dished out area of the wheel. If you put them on the other side you will not be able to get a tire onto the wheel. This means that on some wheels the beadlock will be on the inside of the wheel, by the brakes. If this is not your desired result you may not have wheels that are suitable for making into beadlocks.
The next step is to take a grinder or wire wheel and clean all the paint, rust, and grime off the lip of the wheel that you will be welding to. This picture shows the area that needs to be cleaned, and it also shows the offset "dished out" area that I talked about earlier.
Once you've got the lip all cleaned up go grab one of your beadlock rings. Take a look at the edges of the ring. The edges on one side will be sharp and square. The edges on the other side will be slightly smoother and rounder. You want the shoother edges to be in contact with the tires, so lay the side with the sharp edges down on your wheel. Feel all the way around the ring and move it until it looks and feels like it is perfectly centered on the wheel. You also want to rotate the ring so that the valve stem of the wheel is in the middle of two bolt holes. You don't want to have one of your beadlock bolts interfering with your valve stem. Here's a picture of what you should have at this point.
Now that the ring is positioned where you want it, go ahead and tack-weld it into place in about four spots around the wheel.
Now find a comfortable spot to sit, and start welding. This weld needs to be pretty close to air-tight, so a quality weld is important. Most of the leaks come from where the welds start and stop, so two welds overlap. I try to make as few welding passes as possible. I can usually weld all the way around the perimeter of the wheel in four or five different sections. Some people say you should weld in many smaller sections to avoid heating up the wheel too much and warping it. That is good advice on many other projects, but I don't think there is any way you are going to warp your wheel, so to minimize the possibility of leaks I weld in as few different sections as possible.
This next step is something that some people do, and some people don't. After all the rings are welded up I like to grind down the welds a bit. This knocks off all the high spots and rough spots that make the tire harder to mount. Remember, when you go to mount your tires on these wheels the inside tire bead has to slide over this weld.
Next step is painting, and you already know how to do that... For the best results spray the bare metal with a primer before you spray your color. This will help the paint stick and last longer.