My wife and I were looking through a pet supply catalog and we came upon this rake/pitch-fork thing that was supposed to allow you to pick up dog poo without tearing out the grass or smearing the fresher poo. Since this is what our jaws of life pooper scooper does my wife expressed interest. At $29.95 I wasn't interested, but said what many folks who frequent this site say: "I can make one of those!"
It took longer than expected and caused me a bit of frustration but in the end I did complete a dog excrement extractor. And the price of the one in the catalog promptly dropped to $15.99. But I still came in cheaper.
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Step 1: A Little History
My original intention was to use a leftover piece of aluminum stock from my bench vise work protector project as the attachment point for the poo lifting tines. This is what I call Plan A. I tried using epoxy to accomplish this. It didn't work.
Plan B was to use epoxy in a warmer environment. I thought the cold was screwing with the ability of the epoxy to set-up. I was wrong because Plan B didn't work either.
Plan C was to use special metal bonding epoxy. It was special in that it didn't bond worth shit.
Plan D is where I ended up. This entailed ditching the aluminum stock and using a plastic frame filled with epoxy similar to how I made my gutter rake. This worked and will be the version detailed here. Because of these ups and downs I didn't do this project as efficiently as I would have liked. Specifically I would have gotten all the parts built and then epoxied everything together. This is how I'm going to present the project and hopefully it will flow well. However, I think there will be some minor discrepancies between the photos and descriptions because of this. If you would like clarification on a point please feel free to ask.
Plan E would be to try using the aluminum stock again with JB Weld. I didn't think of this until I was half-way done with Plan D.
Step 2: Materials
- A bent pipe that comes with shower head replacement kits
- A dowel that fits snugly inside the pipe
- Three bolts/screws with nuts
- The edge from a plastic container
- Support spines from windshield wipers (Approximately 6-8)
- Epoxy (2 or 3 packages)
- Disposable containers/stirrers to mix epoxy in/with
- Primer and spray paint
Step 3: Tools:
- Bench vise
- Dremel with cut-off wheels
- Drill with bits (A drill press would be better)
- Drill bit/screw sizer
- Jig saw
- Ballpeen hammer
- Screw driver
- Packing tape
- Safety goggles
Step 4: Attachment Plug Prep
In order to attach the tine mounting base to the poo extractor you have to fill in the pipe. To do this I chose to use a portion of the dowel that will become the handle.
Stick the dowel in the short end of the pipe and mark the dowel with a pencil at the edge of the pipe. (picture 1)
Secure the dowel in the bench vise and cut at the pencil mark using a jigsaw. (picture 2) Then retrieve the part you just cut off from beneath whatever heavy object it rolled under.
Now determine the diameter of the screw you intend to use to secure the tine mounting base to the attachement plug with. (picture 3).
Once you've determined the diameter of the screw secure the plug vertically in the bench vise and drill down through the center of the plug using an appropriately sized bit. (picture 4)
Now if you're like me, you will have let the drill get a little off course so that your bit exits near the side of the plug instead of dead center. (pictures 5 & 6) If so remember three things:
1) the hole you started from is still on center
2) no one will see the off center side as it will be in the pipe
3) if anyone dose see it say you did it intentionally so that the head of the screw will wedge against the pipe wall for added strength.
Once this is done thread the nut on the screw and leave a space that is about as wide as one side of the tine base. Then cut of the excess screw (if any) with a Dremel.
Now set this aside.
Step 5: Handle Prep
Next we'll work on preparing the handle for attachment. Figure out where you want the screws to pass through the long leg of the pipe to attache the handle. Mark these spots on the pipe. (picture 1)
Determine the diameter of your screws. (picture 2)
Drill through the pipe. (Not pictured) The hole you drill through the first side should act as a guide for drilling the hole through the other side.
A trick for drilling metal:USE AT YOUR OWN RISK TO YOURSELF AND YOUR DRILL!!! If your bit binds up in the metal, stop drilling and put your drill in reverse. Pull the the trigger and press the bit down into the metal as if you were still drilling forward for a few seconds. This creates a nice little smooth cone that will allow your drill to bite into the metal without binding. Finish drilling through the metal with the drill in the forward position. This is probably very bad for the drill motor (as I'm sure some pedantic wanker will tell us) so try it at your own risk.
Use your drilled pipe as a template to mark the dowel. (picture 3)
Secure the dowel in the bench vise and drill one of the holes. (picture 4)
Next put the dowel in the pipe and align the holes. Pass the screw through the holes and secure with a nut. (picture 5) This will ensure that the second hole you drill through the dowel will be properly aligned. Drill the second hole. (not pictured)
Step 6: Tine Base Prep
Determine how wide you want your shit fork to be. Mark this on the tub edge. (picture 1) Then cut the edge free of the tub. (not pictured)
Next figure out how far apart you want your tines and mark them on the recently liberated tub edge. I decided to place the tines at 1/2" intervals. This will also let you figure out how many tines you'll need. In my case it was 15 tines. (picture 2)
Heat up a piece of windshield wiper spine with a torch. (picture 3) Once it's nice and hot push the heated metal through the mark on the plastic. (picture 4)
Try to keep the holes as even with each other as possible.
Now flip over the edge and mark the middle of the plastic. Drill a hole that will accomidate the screw used in the attachment plug we built earlier in Step 4. In my case I wasn't coordinated or patient enough to thread the nut on the screw in the tight confines of the plastic. So I cut a notch that would let me snap the plastic onto the screw once the nut was in place. (picture 5)
Step 7: Tine Prep
Now it's tine time. Figure out how long you want the tines. I went with about 6" in length. In order to create more surface area for better attachment and more strength I bent one end so it could be epoxied to the inside of the tine base. Make sure the bend isn't so long you can't move the tine in the plastic.
So mark your desired tine length on the windshield wiper spine. (picture 1)
Cut the spines with a Dremel or other implement of slicing (picture 2) Now they are tines.
Mark where you want to bend the tine (picture 3)
Place the tine in your bench vise (picture 4)
Bend it with your hand so that it is close to being horizontal (picture 5)
Deliver a few mighty whacks to the bend to make the long part of the tine perpendicular to the short part secured in the vise. (picture 6)
Step 8: Install Attachment Plug
Now we begin to assmble the shit fork.
Mix some epoxy in a disposable container. Dip the screw destined for the attachment plug in it. Pass it through the hole in the plug. Then smear epoxy on the outside of the plug and feed it into the short end of the pipe. Allow it to set up.(pictures 1-5)
Step 9: Attach Tine Base
Next grab the plastic tine base. Smear some epoxy on around the hole you drilled for the attachment plug screw. Pass the screw through the hole in the plastic and then tighten the nut w/ a wrench.
Step 10: Handle Assembly
Mix up more epoxy. Dip the end of the handle with holes drilled in it into the epoxy. Slide it into the long end of the pipe and align the holes. Pass the screws through the holes. The high viscosity of the epoxy may make this difficult, but press hard and it should pass through. Use a wrench and screw driver to tighten the nuts. Then allow it to set up.
Step 11: Tine Installation
Dip the bent ends of the tines into the epoxy. Pass them through the holes in the tine base. Press the bent end up against the inside wall of the back of the tine base. Prop them up to keep the tines in place to ensure they don't move. Allow the epxoy to set up.
Step 12: Fill the Tine Base
In order to strengthen the fork we're going to fill the base with epoxy and make it one soild chunk. Wrap the open ends of the base with packing tape. The epoxy won't stick very well to the packing tape so it makes a good temporary mold. (I learned this tip in this instructable by Zach)
Once you've taped off the ends mix up a lot of epoxy and pour it into the base. Make sure you use something to work the epoxy under the tines in order to encase them as completely as possible.
When the epoxy has hardened peel off the tape. Use your Dremel to grind down any excess epoxy.
Step 13: Prime & Paint
This step is self explanatory. Pick you paint and follow the instructions. I used an interior/exterior paint in order for it to stand up to the elements. The lovely olive color was chosen b/c that's what was on hand. Plus with a color like this you just don't feel bad about sliding it under a big lump of crap. Once the paint has dried begin forking poo.
Step 14: Lessons Learned
Before I did the assembly I should have coated my work bench with packing tape. This would have made clean-up much easier. In the picture below you can see where epoxy spilled on the bench and solidified. Now I'm going to have a lot of scraping to do.
In retrospect the attachment plug could've been simplified. Instead of drilling a hole through it and using a nut it would have been simpler to just drive a screw through the tine base into the plug. Once this was done I could've epoxied it into the short end of the pipe.
A drill press would've ensure straighter and better placed holes.
I also would have tried to make the tines more level w/ each other. The uneveness hinders poo-forking at times, but w/ a little practice you get onto it.