How to Make a Shrinking Stump | Sheet Metal Fabrication

Got Wood?

Now I’m going to show you my method for making a “shrinking” stump. Like a lot of things, there isn’t necessarily a right or wrong method to do this. As long as you are able to produce results in the end, who cares how you get there? Earlier, we went over how to stretch and shrink metal using a shot bag and flat stump. The theory behind a shrinking stump is very much the same. Create a “tuck” in the sheet and planish it back out to create a shrink. However, using a shrinking stump is much more aggressive and can shrink a lot of material quickly. This is a good thing. The two methods still have their place.

In order to make a shrinking stump, the first thing you are going to need is obviously a tree stump. The stump can be as large or as small as you want it to accommodate the work you will be doing. You will obviously want to choose a stump that is solid and hard. If you can get it, a hardwood like oak would be a good choice for a shrinking stump that should provide a lifetime of service.

To show you how simple a shrinking stump can be, however, I am going to make a shrinking stump out of a wooden stool I made from a slab of a solid elm tree trunk. I don’t know how long it will last, but I’m positive it will work well and will be light and portable. I’ll even still be able to use it as a shop stool!

how to make a shrinking stump

Step one will require the use of a handheld circular saw with a standard wood-cutting blade.

Words and Photos: Big Joe

how to make a shrinking stump

We are going to use the circular saw to cut a dish into the top surface of the stump. I don’t want a very large dish, nor do I want it very deep for this application. So I set the blade depth on my saw to roughly 1-1/4 inches. Keep in mind through this process that any depth or shape dish is perfectly acceptable. Different uses will actually necessitate different dished surfaces for stump shrinking.

Words and Photos: Big Joe

how to make a shrinking stump

I determined the exposed blade on my saw is aproximately 5-1/2 inches long, so I drew a 5-1/2-inch diameter circle where my dish will be. I also drew a few diagonal reference lines through the center of the circle. This is where I will plunge the saw blade into the stump surface. Take time to note that I offset the dish on the stump surface. This will allow me plenty of flat surface to planish out the tucks you create in the dish. I may also choose to put another dish in the stump of a different size and depth.

Words and Photos: Big Joe

how to make a shrinking stump

You will see how I used the circular saw to make repeated diagonal cuts within the circle to begin to carve out the dish.

Words and Photos: Big Joe

how to make a shrinking stump

You will see how I used the circular saw to make repeated diagonal cuts within the circle to begin to carve out the dish.

Words and Photos: Big Joe

how to make a shrinking stump

I then took a hammer and wood chisel to remove the remaining slivers of wood in the dish.

Words and Photos: Big Joe

how to make a shrinking stump

I then took a hammer and wood chisel to remove the remaining slivers of wood in the dish.

Words and Photos: Big Joe

how to make a shrinking stump

After using the hammer and chisel, I chose to use the circular saw once again to carve out the dish by rotating the saw within the dish to smooth out the shape a bit more.

Words and Photos: Big Joe

how to make a shrinking stump

Then I went to an abrasive disc on a pneumatic angle grinder to finish it off.

Words and Photos: Big Joe

how to make a shrinking stump

I chose to round off half the edge of the stump surface so I also have a radius edge for additional shaping.

Words and Photos: Big Joe

how to make a shrinking stump

The last couple steps are purely final finishing. I took a swatch of sand paper and hand sanded the dish and flat surface to smooth everything out nicely.

Words and Photos: Big Joe

how to make a shrinking stump

I also chose to use some butcher-block conditioner to oil the entire stump surface. Not only does this make the stump look nice, but it will help the stump to wear nicely and will give a good, slick surface for shaping.

Words and Photos: Big Joe

how to make a shrinking stump

Well there you have it. We now have a nice portable and handy shrinking stump to do some quick metal shaping. Later we will dive into how this homemade tool can make your metal-shaping life easier!

Words and Photos: Big Joe