This Instructable was inspired by member CobyUnger'sManual Chainsaw. He did a great job creating a versatile tool that fits right in your pocket. My only hesitation with creating his version is that I tend to abuse my tools and I had concerns that the fabric strap would become frayed and fall apart over time. So I modified the design a bit to put on some pipe handles.
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Step 1: Materials and Tools
Materials you will need:
(1x) chainsaw blade. I think the one I used was around 30" long
(2x) 3/4" pipe caps
(2x) 3/4" pipe nipple, 5" long
A small amount of concrete mix
Some water (for the concrete)
Tools you will need:
Metal grinder with a cutting wheel
Small hand file
Tape measure / ruler
Several clamps, although not necessary, definitely helpful
Paint stick / Mixing stick
Leather work gloves
Step 2: Cut the Chain
The first thing I did was cut the chain using the grinder and a cutting blade. The grinder made quick work of the blade. I simply clamped the chain to a board, and came in from above between the links. If you don't have a grinder, I'm sure this could also be accomplished with a hacksaw.
Step 3: Grind the Pipe Caps
The next step was to make a slot in the pipe caps to allow the saw blade to be fed through. I clamped the pipe caps tightly in a vise and slowly cut a slot through the cap. I then cleaned out the slot with a file.
This would be a tough job without a grinder. If you are able to get through those caps with a hacksaw, then more power to you.
Step 4: Feed the Blade Through
Screw the caps onto the end of the nipples to create two handles.
Then feed each end of the chain through the slots into the handle. Keep feeding chain through until you have about 5" of chain coming out of the back end of the handles.
Finally, wrap tape around the blade between the 1/2" and 1 1/2" mark. Keep wrapping tape until it builds up and barely fits into the pipe.
Step 5: Pull the Tape In
After you've wrapped the tape around the blade, pull the blade (wearing gloves of course) so that the tape is pulled into the handle. Keep pulling until you can see the tape peaking through the slot.
The objective is to have the tape create a seal against the pipe cap once it is pulled into place.
Step 6: Mix and Pour the Concrete
To hold the blades in the handles, I used premixed Quikcrete Concrete mix. The stuff came with a lot of larger aggregate mixed in. The mix needs to be fine enough to be poured into the pipes, so I sifted it through my fingers until the bigger chunks were removed.
I have no idea what the water/concrete ratio was. There was so little concrete being used that I didn't bother calculating it. I just mixed it into a slurry that was manageable. Use a paint stick to mix the concrete into a smooth milk-shake consistency.
Right before scooping the concrete in, I sprayed the interior of the pipe with WD-40. In my mind, this provides some additional protection from the blades becoming rusty while the water evaporated out of the concrete. Does it actually make a difference? Got me.
Use the paint stick to scoop the concrete into the back of the pipe. The concrete tends to get gooped-up near the opening. Knock the pipes with a rubber mallet will allow the concrete to work down.
Step 7: Let It Dry
You will want to let the saw sit for a few days so that the concrete has enough time to set. I found that it took a while for the concrete to completely dry (I think I left it for 5 days or so). I used a couple clamps as stands so the wet concrete wouldn't spill out.
Step 8: Possible Improvements
This guy can boogie through branches pretty well. I plan to add a 90-degree elbow and another 5" nipple to each handle, so that the handles are L-shaped. I think this will make the ergonomics of this saw much better
Since posting this Instructable, several members have thought of clever improvements:
Member bjkayani suggested adding a T to the end of the handle, so that two people could operate the saw, one on each end.