Why Make a Sinking Station?
One of the most obvious things about making pans is that it's pretty physical work. Whether you're using the air hammers or doing it by hand, there's a lot of energy expended in stretching the steel, and we want to do this as efficiently as possible.
Below are 4 variations of my sinking station as I've developed it over the past decade.
The physics behind this
When the hammer strikes the steel, it transfers the kinetic energy of the hammer into the metal. The metal will respond in three ways - it will move as a whole, it will stretch, and it will dissipate energy as noise. The thing we want to aim for is to get as much of the energy to go into the "stretching" response, and as little as possible to go into the "moving" response. Your neighbors couldn't care less about the ratio of the first two, but for darn sure they're interested in as little energy as possible going into the "noise" part!
If the barrel is free to move, then a lot of energy is wasted in just moving the barrel around the workshop. And so it's important to limit the ability of the barrel to move, so that we can maximize efficiency in stretching the steel. Additionally, we really want to have as little noise generated as possible.
There are a couple of ways to accomplish these things.
Basic Sinking Station
This is comprised of the following:
- the Sinking Foundation - 200lbs of cement inside a barrel cut to 10", with a metal post sticking out the top
- a Lazy Susan made from two 3/4" Plywood circles and twelve casters
- the Sinking Base - 150lbs of cement inside a barrel cut to 14", with a hole in the center to go over the Sinking Foundation Post.
- some Clamps to hold the Pan to the Sinking Base
- A bunch of blankets or pillows to pad the drum
A Simpler but Still Effective Variaton
If the Basic Sinking Station seems to be a lot of work just to get going, you can omit the Sinking Foundation and Lazy Susan, and just make the Sinking Base.
If you don't want to deal with mixing and pouring cement, you can fill the Sinking Base with a couple of old car tires that fit snugly into the drum. Drill holes through the side of the Sinking Base into the tires, and put drywall or sheet metal screws through the holes into the tires to keep them in place.
The downside is that you wont be able to turn the pan very easily while you're hammering on it.
The Spider Sinking Station
The Spider Sinking Station comprises
- A Floor Stand with lugs so it can be repositioned around the workshop (optional)
- a Sinking Foundation with 200lbs of cement and a metal post
- a Lazy Susan made from 3/4" Plywood and casters
- the Spider - welded 1" steel with 12 or 16 3/4" inserts, each with a 3/8" bolt and two 2" x 1/8" steel washers
- Blankets for padding
There are clear advantages to making pans from oversized barrels (assuming you keep the ranges the same). One disadvantage is that you need a different sized Sinking Base for each size of pan. In my workshop we make pans on 4 different sized barrels. So we have 4 different sized Sinking Bases - each weighing 150lbs or more. They're a pain to switch out since we have to use an engine crane, and it takes 30 minutes or more to do it. Additionally, we have to find a place to store them and they're hard to move around even when they're on casters.
In late 2020, during a visit by Noah Sanderson, we designed a variable size Sinking Base. This comprises a metal spider-like assembly (with 16 legs) and inserts that can be expanded or contracted to the required diameter for the pan.
Since I was redesigning things, I made a few changes to the Lazy Susan arrangement. I expanded the size of the Lazy Susan top plywood board, and bolted the Spider down to it. The expanded board provides a comfortable place to rest one's feet. It also allows me to rotate the barrel with my feet while I'm hammering (similar to a potter's wheel).
As soon as I used it the first time out, it was obvious to me that this was a winner in so many respects. Almost immediately I made a second one for the other workstation we have at the shop. I've been able to get rid of the concrete Sinking Bases that were starting to clutter up the place - we had 8 of them! Switching between drum sizes is a breeze now, not a chore. It's hands down the most efficient solution I've used to date.
Easier Methods
If all of this seems like more work than you're interested in doing, there are a couple of really simple ways to get started. They're maybe not as flexible as what I've developed, but they'll get you going quickly and cheaply.
With some of the first pans I made, I took the complete barrel and filled it about 2/3 full with water (you can't fill it completely since you have to leave room for air to compress as you sink the pan). Then I closed up the bungholes and turned it over.
You'll notice how nonchalantly I said "turned it over"... a 55 gallon barrel holds 210 liters of water, and so weighs about 140kg (300lbs) if it's 2/3rds full. It was a huge effort to flip it over, and it really is a 2 or 3 person job. But once you have it flipped over, a 300lb barrel is not going anywhere when you hit it with a hammer. Additionally, all that water in the barrel does a pretty good job of damping the noise, with the exceptionof the actual pan surface, since that is not damped at all.
There are some downsides to this. For a start, you have to drain the water out when you're done, and so it's wasted and makes a bit of a mess. More problematic is the issue that the water trapped inside the barrel tends to go through a cycle of evaporation and condensation as the outside air temperature changes during the day and night; and so the steel inside the barrel is constantly being exposed to this cycle. Water and steel means only one thing: RUST. So the pan tends to rust on the underside pretty quickly.
If you're going to get the pan built in a day or so, this may not be a problem, but if you're only working part time at making a pan, and it may take several weeks to get the thing done, then this is going to be a problem for sure. Rust means pitting, pitting means weak spots, weak spots means tears. Ask me how I know.
As you build more pans and start buying new barrels that have no bunghole, this method is clearly not an option.
But to start with, it's a very cheap way to stop the barrel moving around.
Used Car Tires
Right after I figured out that water rusts steel, I switched to stuffing the barrel with blankets to get some noise damping on the head. It's easy to put blankets/cushions/pillows etc into the drum, but it's more of a challenge to keep them in place so that they stay pressed up against the head.
It turns out that there are car tires that fit pretty much exactly into a 55 gallon barrel. For quite a long period from the late 80's into the mid 90's, I would use these to hold blankets against the head of the drum. The tires added weight and damped the noise from the skirt.
Essentially I would use a chisel or sharpened piece of 1/8" steel to cut open the bottom end of the barrel that has the bungholes. Then I would smooth out the jagged edge as best I could so it wasn't an injury hazard.
I'd dump a bunch of pillows and comforters/duvets into the barrel to fill it about 1/2 full. (You can get cushions for about a dollar each from thrift stores).
Then I'd compress these against the surface by pushing a few car tires into the barrel as if I was stacking donuts on top of each other. I'd drill some holes in the side of the barrel and put wood or drywall screws through these holes into the tires to hold them in place. The net effect was a drum that was pretty heavy and well cushioned.
Bass Pans
You may be wondering about how I sink Bass Pans with these contraptions. I'll describe this later and either add it here or put a link to it.