Warning: may contain a book because I like to explain my thought process or lack thereof.
Guys, I think I did it. Now a lot of people know of the hair dryer in a bucket trick for heating a bowling ball. Some people have also used a food dehydrator. Both of these have one key element I do not like: they heat from the top. And at least in the case of the hair dryer, it will blow hot air directly on the ball. This causes uneven heating of the ball.
I can think of two ways to heat a ball evenly:
1. Water bath. A while back, some of you may remember, I tried using warm water in a bucket to deoil a ball. I used a hair dryer to try to heat/maintain the temperature of the water for an extended time. It was an epic fail, so scratch this idea. There are ways to make it work, but not in the ways I am willing to do it. I don't want to constantly monitor the temperature of the water and keep adding in hot water.
2. Promote air currents and heat with indirect heat. Now this idea works. Keeping in mind I work in a weld shop, some stuff I have access to made this a really easy project to do. Using a hair dryer, the air currents are already there. It is just finding a way to control how they flow. I want the currents to swirl around the edges of the bucket in order to heat all around the ball. To do this, the dryer must be inserted through the side of the bucket at an angle. (will try to include pictures.) the roundness of the bucket and the physics of heat rising takes care of the rest. Also, since the heat is rising, it warms the ball as it goes up to the top, there it collects and raises the overall temperature of the bucket.
Vent holes! Bucket has to have them! There are two reasons. One is to help control the temperature of the bucket. The other is to control air pressure. Maybe it is just that I have a junk hair dryer from 15 years ago, but if the pressure is built up top high in the bucket, it kicks the motor down into an ultra low mode and doesn't heat. Anyway, like they say in business, LOCATION LOCATION LOCATION. The location of the vent holes matters nearly as much as the size and number of them. I used a 3/8 drill bit because that just seemed like the right size for vent holes. And it works. Obviously you don't want huge vent holes because that will let out too much heat. Likewise, too small doesn't let out enough heat and the bowling ball will overheat. I started out having vent holes in the top. The problem with this is that it doesn't let the heat build at the top of the bucket and the overall air temperature doesn't get hot enough. So I taped off all the holes but just a couple of them. Also the bottom of the ball was the only part getting warm. So I tried drilling holes at the bottom of the bucket. Bingo! This let heat build at the top while letting excess heat out the bottom so the bottom doesn't get too hot.
Controlling temperature
This is the hard part. Running the hair dryer on low, I was only getting 120 degrees at the top of the bucket. I had too many vent holes at the bottom sides of the bucket. This wasn't hot enough to pull as much oil out as I wanted. Manufactures recommend not getting the ball above 140 degrees, so that, naturally, was my target temperature. I started taping off holes until I got to the ideal temperature. One interesting thing I found was taping off different holes changed the temperature differently. If I taped off holes closer to the dryer in the line air was blowing, the temperature in the bucket rose dramatically. If I typed them off at the other end of the dryer where the holes weren't as close to the air coming out of the dryer, the air temp did not increase nearly as much. So I played guess and check until I got the temp to maintain 140. I also still had 1 vent hole open on top plus a second one the thermometer stayed in. This will change, but more on that later. At least I had the temperature figured out
Keeping ball of direct heat
This part was really easy for me, but may take a little more work for some people. I didn't want the ball sitting directly on the bottom of the bucket because I don't want the hair dryer blowing directly on it. I also don't want anything metal for the ball to sit on because of metal absorbing the heat. I was worried about it melting a flat spot in the ball. I had some 4"pvc pipe laying around that seemed perfect for a ball rack. It was just a short piece so I had to find something for that to sit on. I just happened to have a piece of good sized steel channel drop laying around. It was tall enough to raise the ball to the level I wanted but wasn't too long for the bucket. Added bonus, I could position the channel in a way to help direct the air currents. Between that at the pvc pipe, the ball is up just below the lid.
Baking the ball
I baked the ball with it. Lol. One thing I noticed was that the temperature was not rising well once I put the ball in the bucket. The ball is a lot to heat up when you have it dialed in to hold at 140 degrees. I ended up taping off one of the holes to help build the heat a little faster until it was up to temperature. Then I removed the tape from that hole and it held just below 140.
I currently have a second ball in the oven now. Going to give it a full run and see how much oil comes out of it. I got a surprising amount out of my Storm Ride because I felt like it was going dead on me Thursday night. That's why I wanted to try this. I was experimenting with the bucket while I was baking it. My Motiv Forza is my second one. We will see how it works. It is a Motiv though, so I may not get anything. Anyway, thoughts on this bucket?
