Introduction: Make a Chainsaw Stump Vise

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About: I miss the days when magazines like Popular Mechanics had all sorts of DIY projects for making and repairing just about everything. I am enjoying posting things I have learned and done since I got my first to…

A stump vise for a chainsaw is a handy accessory for sharpening a chain wherever you are cutting. Tap on the vise to drive the prongs into the wood of a stump or a log enough to anchor it. The vise holds the chainsaw bar so the chain can be advanced by hand after accessible teeth have been filed. It can also be used on a countertop without driving the prongs into the wood, or set on the end gate of a pickup truck. A good stump vise provides solid three point support. If not used on a stump you may want to place a piece of wood under the sharpened prongs to protect the surface below.

You can buy a commercial stump vise for relatively little, but I designed mine with a couple of additional features that may make building your own worthwhile.

(For your information, the chainsaw is a factory refurbished Husqvarna 440 with 18 inch bar.)

Supplies

Materials

  • 1 x 1 inch square tubing with walls 1/8 inch thick.*
  • 5/16 inch bolt threaded its entire length or threaded rod
  • 5/16 inch Tee nut for furniture, etc.
  • 1/8 x 3/4 inch steel bar
  • 1/4 inch steel plate
  • 1/8 inch steel rod
  • 5/16 inch steel rod

*I needed to make more of these stump vises for a group. I ran out of square tubing with 1/8 inch walls, but have some with 1/16 inch walls. I placed the prongs inboard so they are directly under one wall of the 1/16 inch vertical tubing. I am confident the vise will be sufficiently strong for normal use.

Tools

  • Hacksaw or metal cutting bandsaw
  • Square and measuring tools
  • 230 volt stick welder
  • 125 Amp. MIG welder
  • Spring clamps
  • Pliers
  • Vise
  • Drill press and bits
  • Adjustable wrench
  • Hammer
  • Grinder with flap disc

I cut three pieces of square tubing. Two were just over 4 inches in length. The third was just over six inches in length. I used a flap disc on a grinder to remove rust and scale for better welding.

Step 1: Mount the Tee Nut

I drilled a hole through the front and rear faces of one of the shorter four inch pieces of square tubing. I made the holes 11/32 inch in diameter so the 5/16 inch bolt would turn freely if the Tee nut were not precisely enough aligned. The front hole was enlarged to 13/32 inch so the body of the Tee nut fit nicely. I used a countersink bit to make room for the shoulder on the Tee nut.

I used a pair of pliers to break and remove the sharp anchor burrs. (second photo) I welded the Tee nut to the square tubing so it does not turn when the bolt is turned to tighten the vise on the chainsaw bar. (third photo)

In use lubricate the bolt in the Tee nut with oil or grease.

Step 2: Spacer Pad

The chain is wider than the thickness of the chainsaw bar. I cut a piece of 1/4 inch steel plate 1 inch by 1 inch and welded it to the other shorter piece of square tubing so it corresponds to the position of the bolt and Tee nut.

Step 3: Weld the Shorter Pieces to the Longer Piece

The goal is to have two upright members of the stump vise parallel to each other when finished. It sounds easy, but welding involves laying down hot metal that shrinks as it cools, and that pulls things in different directions. In the photo the near upright piece is already welded. The far piece has been tacked, but not fully welded.

I planned my welds like this. First I placed a tack weld between the base piece and one corner of an upright. While the weld was still hot I placed the base piece in a vise and used an adjustable wrench to adjust the upright piece a tiny amount as needed. After it had cooled some, I placed a tack weld on the corner diagonally opposite from the first tack weld. I let it cool, but did look to see if everything was still properly aligned. When it had cooled more I placed tack welds at the two other corners and let them cool. Each additional cooled weld reduces the opportunity for parts to move.Then I welded along each side between the tack welds. When I was finished, the uprights were parallel as hoped. I did weld the facing joints on the base. Pressures on the chainsaw bar would make the uprights want to move apart from each other. Front side welds would add strength. I did not weld the opposite sides unless the uprights went a little out of alignment during welding. Then a weld on the outer joint served to pull the uprights apart from leaning into each other.

The space between the uprights is 1 1/4 inches. The bar on my chainsaw is just a little more than 5/32 inch in thickness.

Step 4: The Buffer

Commercially available stump vises have the bolt’s end twisting against the chainsaw bar. I wanted to place a piece of 1/8 inch steel between the end of the bolt and the face of the chainsaw bar to make actual contact with the chainsaw bar.

The first photo is from a failed attempt to mount a hinged buffer at the top of the upright with the bolt and Tee nut. The first photo shows how I bent 1/8 inch rod to make a hinged mount. I salvaged that and reused it as you see in the second photo. Gravity causes the arrangement in the second photo to open when the bolt is retracted. The third photo shows my buffer in use with the chainsaw bar clamped firmly in the vise. My buffer will spread clamping pressure and protect the chainsaw bar from swirl marks and too much pressure in one area. A little thought is needed to make the bends in the 1/8 x 3/4 steel so it clamps the bar, but does not restrict the chain’s movement. The bent rod shown in the first photo has to be opened to pass over the square tubing. Then use a hammer to close the ends of the bent 1/8 inch rod.

Later I began to use 16 penny nails for the rods. I removed the heads and the points. I found some steel rod the thickness of the chainsaw bar and made a “V” I could clamp as a substitute for the chainsaw bar. I clamped the “V” in place and bent the nails as needed to fit. Then I welded the nails to the buffer piece. This guaranteed the fit and the action would be very good.

Step 5: Leverage for the Bolt

I shortened the bolt to make more room for a hammer when setting the anchor prongs into a stump. The photo shows the setup I used for welding the smooth rod to the threaded bolt. The nut on the threaded rod made it easy to hold the bolt in a viseand allowed using the jaws to hold the pieces for welding.

Step 6: The Prongs

I cut two pieces of 5/16 inch rod. Each was 2 1/2 inches long. I spun them in an electric drill while holding them to a grinding wheel. I tapered them like a sharpened pencil. The tips burn easily. Stop and allow them to cool while grinding. Drill 5/16 inch holes through the bottom face of the six inch square tubing. (second photo) I welded inside the square tubing to secure the prongs.

Step 7: How to Use

To use, tap the prongs into the top of a stump in the woods, or hold the stump vise upright if using a counter. Retract the bolt. Wear gloves or use a rag to protect your hands from being cut on the chain. Slip the stump vise over chainsaw bar. Position it so it does not restrict movement of the chain by hand pressure. Tighten the retaining bolt. File accessible teeth facing one side and then the other. Check and file the depth gauges as needed. Loosen the chain brake and advance the chain to make new teeth accessible.

The two features I built into my stump vise are a wider base for more stable support of the chainsaw, and a buffer to protect the chainsaw bar from the end of the bolt. My stump vise is bulkier and heavier than the commercially produced version. But, I like its extra features.