There are a couple of ways to make a Sinking Base
Basic Sinking Base
The simplest sinking base is made using just the bottom end of the barrel. I usually cut the barrel about 15" tall using metal shears.
You can either mix up 2 or 3 50lb bags of concrete and pour them into the barrel, or get a couple of car tires with a 22" Diameter and put them in the barrel. If you use the car tires, I find it useful to drill a few holes in the side of the barrel and either bolt or screw the tires in place.
The one in the image here has been well used. I've built a lot of pans on it.
Advanced Sinking Base
A more advanced sinking base would be mounted on the Lazy Susan assembly on top of a Sinking Foundation. This allows it to rotate, and is a much more convenient way to sink pans.
Materials
- Bottom half of a barrel, cut to 14"
- 3 50lb bags of cement
- 3 gallons of water
- 1pc 1 1/4" Pipe Flange
- 1pc 2" x 1 1/4" Nipple & Cap OR 1pc 6" x 1 1/4" Nipple
- 4pc 1" x 1/4-20 bolts
- 4pc 1/4-20 Nylock Nuts
- Gorilla Tape
Tools
- 1" Hole Saw
- 1/4" Drill bit
- 7/16" wrenches
- Metal File
- Electric Drill
- Shovel
- Bucket
- Gloves, Respirator, Protective Gear
Decisions....
First off you need to decide if you're going to use the 6" Nipple or the 2" Nipple-and-Cap.
The advantage of the 6" Nipple is that it gives you a hole completely through the Sinking Base. This is useful if you have several different diameter drums that you're working on, since you'll need to align this hole with the vertical post on the Sinking Foundation every time you switch out the Sinking Base. Having a hole all the way through allows you to see when the post is aligned.
Switching out the Sinking Base is not trivial - I used an engine crane and straps, and it took 30 minutes or so to get it done. It was a pain in the butt, but we did this in my shop for 7 years or so before I designed the Spider Sinking Base.
If you go with the Nipple-and-Cap, there is no hole through the Sinking Base, and its more difficult to line it up if/when you switch them over. However, the advantage is that you can more easily seal the top of the concrete so that there is no dust released as you hammer on the drum.
Making the Base
Drill a 1" hole in the exact center of the drum.
File the edges of the hole so that they are not sharp.
Position the flange over the hole, on the inside of the drum. Mark the positions of the four mounting holes, and then drill those using a 1/4-20 drill bit. You may need to drill out the actual holes in the flange too depending on the quality of the casting.
Bolt the flange in place and tighten it down. I put the bolt heads on the underside of the drum, and the nuts on the flange. Use flat washers on both sides.
If you opted for the 6" Nipple, then screw it into the flange.
Alternatively, assemble the 2" Nipple and the Cap, and then screw this into the flange. The photo of the 2" Nipple and Cap that I show here is actually from the Lazy Susan for the Spider Sinking Base, but it shows the concept.
Fill the thing up with 150lbs of cement/concrete and let it dry, and then seal it either with Gorilla Tape, or a wooden board and Great Stuff Foam. I've toyed with using a layer of epoxy....if you do it, let me know how it works!
Final Thoughts
I've used these systems for sinking pans for decades. They work really well. The only drawback is that you have to have a different Sinking Base for every size drum you work on. I have 4 different diameters that I use; and we have 2 workstations set up at the shop.
This means we really needed to have 8 different Sinking Bases at the shop; at any one time we were only using 2, and we had to find storage for 6 half-length barrels that each weighed 150lbs or more. Each one had to be on a dolly of sorts since we could only wheel them around the shop. It became a storage problem.
Towards the the end of 2020, Noah Sanderson came to visit me, and we brainstormed an idea for a variable-size Sinking Base that could accommodate a drum of any size. The initial drawings we sketched out made it look like a spider, and so it became known as the Spider Sinking Base.
I built one and liked it so much I immediately built a second one for the other workstation. I'm in the process of dismantling all the Advanced Sinking Bases that I've made over the years. Well, except for one that I'll keep for guests who come and study at the shop on what has become the third workstation. Eventually I'll likely build a Spider for that too.