Intro: Step-n-Start - a Motor Pull-Starting Assist for Those That Need a Little Help
I proudly purchased one of those nasty little 2kW generators from Aldi's figuring it would get us by if we lose power after a storm. The only thing I didn't count on is that I'm the only one in the family that can pull start a small engine. When I conducted "Generator 101" at my house I found out that my petite wife and girls didn't have the practice or strength I had and that they couldn't get it started. This instructable details the solution to the problem that my daughter and I built. It is a pedal that one pushes down using the strong muscles in one's legs. It redirects the energy to pull the cord for the Generator.
=== UPDATE 2013-03-04 ===
When we had our last power outage my lovely wife humored me by making an honest AND SUCCESSFUL attempt at starting the generator with the Step'n'start. I was very pleased :)
=== UPDATE 2012-07-26 ===
Many thanks for all of the encouragement. It's really overwhelming with the >10,000 hits in 3 days! We found that the 1/4" bolts for the pulleys are not beefy enough, so please use 3/8 if you build one of these. We had to change them out. We have also found that the 4-to-1 ratio is a bit much and that 3-to-1 works better for our generator. My wife was not successful in trying it tonight, but her hip was bothering her and her electricity wasn't out. Please do let me know how yours turn out if you make one. As an aside, I'm also trying to encourage work ethic in my kids and I've received some PM's about selling them. I asked Emily if she was willing to make them for $30 each and she seemed tickled at the idea. So we are considering selling them via ebay if you lack the resources needed to make one. I think a cottage business where the reward (money) is proportional to the effort invested would be a great way to instill work ethic AND show how an idea and being industrious can pay off. I did check USPS and from Ohio to California it was < $27 shipping. If there is interest and we'll set it up. Again, many thanks for all of the feedback. She thought it was really cool to read it.
Thanks, yeltrow & helper :)
=== End update ===
2 ea. 2x4's 48" long
2 ea. 2x4's 18" long
1 ea. Hinge
1 ea. 3/8x9" (8 can work) bolt
1 ea. 3/8x3" bolt
1 ea. small piece of plywood or OSB 12" x 12" or so for the gussets.
22 ea. 1-5/8" Long Drywall screws
10 ea. 1/4x1.5" Lag Bolts to hold the hinge
10 ea. 3/8 cut washers.
10 ea. 1/4" cut washers
2 ea. 3/8" Lock nuts
4 Pulleys (or make your own from Corean countertop scraps or a cutting board or something else). 3/8" bore.
5ft 3/16" Diamond braided rope
3/8" PVC pipe
7/16" Socket Wrench
3/8" Drill Bit
1" Spade Drill Bit
2" Hole Saw if you make your own pulleys
Step 1: Determine the Length of Pull of Your Generator
We have to know how much cord is available so we don't rip the cord off the machine. I found I had about 50" of cord. I planned to use 4 wraps of the pulleys with about 12" of pedal travel. 4 wrap x 12 in travel = 48 total inches of travel.
Step 2: Get Hole Saw to Make the Pulley
I used a hole saw to cut a disk from some Corean countertop scraps. They are about 1/2" thick. I cut four of them out.
Step 3: Turn a Groove in the Pulleys
I used a lathe to put a groove in the edge of the pulleys so the rope would stay in. We bored out the 1/4" hole to 3/8 with a 3/8" drill bit.
Step 4: Cut the 2x4 to Two 48" Pieces
If you start with an 8 foot long board, you can get two pieces 47-15/16, but that should be close enough.
Step 5: Locate the Hole for the Pulley and Drill
I located my hole about 1.25" in from the end and 1/2" from the bottom edge of the 2x4. This gives us more meat for pushing down on the axle bolt for the pulleys. I wanted the board to be more pressing down on the axle bolt than pulling it down and splitting the grain of the board. My assistant marked the location of the hole by hitting the bolt with a hammer. She then center punched the hole and drilled it clear through the 2x4. A LONG drill bit is needed. Alternately, the hole can be marked and drilled from both sides, but that is harder.
Step 6: Mark the Pedal Board Where the Pulleys Go
We stacked washers in between the pulleys to figure out how wide the notch needed to be. Then we traced the edges of the pulleys on the board to give us a guide to cut by.
Step 7: Use Jigsaw to Cut Slot for Pulleys
Step 8: Countersink the Bolt Head and Nut
We drilled a hole 1" in diameter about 1/2" deep on both sides of the board. This had to be done so the bolt would not rub when the pedal moves.
Step 9: Bolt the Pulleys and Washers Into the Pedal
We inserted a washer on each side of the pulleys to keep them from rubbing against each other. This would make them harder to turn. A nylock (nylon insert lock nut) is used to keep it from coming apart. The bolt should not be too tight or the fork will squeeze the pulleys and make them hard to turn.
Step 10: Measure the Travel to Figure Out How Long the Boards Should Be and Cut
Although 18" is probably a good length it is good to know where this comes from. I wanted 12" of travel so we put the board with the pulleys against the bottom frame piece (the other 48" board) and marked the "start of travel." Then we swung the pedal up and marked where it moved 12". Then we added about 2" for the pulley. All of this added up to about 18".
Step 11: Mark the Upright Pieces and Drill the Pulley Bolt Holes
Each of the 18" uprights will have a 3/8" hole drilled in them to support the other set of pulleys. We put these holes closer to the edge of the board so that when force would be applied to them more wood would be in compression than tension. The first one was marked with the bolt, center-punched, and drilled. We use the first one as a template to locate the bolt hole for the second upright. The bolt was hit with a hammer to transfer a mark to the second upright. Then that upright was drilled. This way we knew for sure that the bolt holes would line up.
Step 12: Bolt the Hinge Onto the Base Board
The "Base Board" is the 48" 2x4 that doesn't have a pulley bolted to it. It gets a hinge in this step. We traced the hinge to make sure it didn't move while we bolted it on. Then we drilled pilot holes for the 1/4" bolts. A washer goes under each bolt head. The 1/4 x 1.5" lag bolts we used to hold the hing on. If you use a different style of hinge you may have to use flat head screws instead of hex heads like we used.
Step 13: Put in One Bolt on the Pedal to Line Up the Hinge
We laid the pedal board on top. Then we traced the hinge for reference as well as we could. Then we swung the pedal all the way up so we could put ONE bolt in the center of our hinge. We drilled a pilot hole for one of the 1/4" lag bolts and tightened it. Then we swung the pedal back down against the other board and moved it side-to-side to twist the hinge so both boards would be lined up against each other when the pedal was all the way down.
Step 14: Complete Bolting the Pedal Hinge Down
We CAREFULLY swung the pedal back up WITHOUT MOVING THE HINGE. Then we marked the holes. Then we center-punched the holes and drilled pilot holes for the remaining bolts. Then we bolted the hinge to the pedal.
Step 15: Make a Set of Gussets for the Uprights
A set of gussets is needed for the uprights. These can be any triangle shaped piece of plywood or OSB. We cut ours in triangles and THEN realized the pedal would hit them on its travel downward. Then we put a set of guide strips on our uprights to keep the pedal from getting stuck on the gussets. An improvement on this step would be to trace the uprights on your gussets and include the guide strip in them as one piece. You might even be able to get away with NO uprights and just the gussets if they are made of thicker material and made 18" tall.
Step 16: Screw Gussets and Guide Strips to the Uprights
We made a set of guide strips from some scrap material the same thickness as our gussets ( again, you could integrate your side strips into the gussets as one piece if you like). We drilled pilot hole and screwed them to the uprights to make two mirror image pieces. Note that the bolt holes are one the far edge of the boards from the pedal.
Step 17: Screw the Uprights to the Base Board
We used four 1-5/8" drywall screws and one 3" drywall screw to attach each of the uprights to the base board.
Step 18: Countersink the Bolt Head and Nut (if Needed)
The pulley that bolts to the upright needs put on. The longest bolt we had was about 8" instead of the 9" I would have liked. We use a 1" spade bit to countersink the head and the place where the nut would go because of our short bolt. It also kind of nice not having it stick out.
Step 19: Cut PVP Pipe Bushings to Center the Pulleys
We had some 3/8" PVC pipe kicking around that we used to make a set of bushings. These center the top set of pulleys so they don't wander. We put the pulleys and three washers through the uprights temporarily. Then we measure the gap we had to fill. Then we marked two pieces of PVC to fill this gap. Our pulleys were 1/2" thick (same as our plywood). We needed to fill about 3.5" inches so we cut the two pieces 1.75" long.
Step 20: Bolt the Pulleys on and Put a Rope on It
We bolted the pulleys on and then it was time for the rope. We threaded the rope through each of the pulleys starting by going from the hinge end. We went over the top of the first pulley. Then the rope goes around each of the other three. We tied our rope off on the bushing on top pulleys with a bowline (google...) so it wouldn't slip. Then we used the propane torch to cut and fuse the braided rope at the same time. We tied an additional bowline in the other end to put the pull start tee handle through. Note: We later untied the rope from the top bolt and tied it to the bottom pulley to change the ratio from 4-to-1 to 3-to-1. This makes it a little easier to start the generator.
Step 21: Ready to Test!
After we tied the rope on it was ready to test. We figured out that my daughter doesn't weight enough with a 4-to-1 or 3-to-1 pulley setup to start the engine. I had no such problem. I don't recommend stomping on the board to start the engine. I used more of the motion of climbing a stair. This started the engine very easily on the first time. I did reduce the ratio from 4-to-1 to 3-to-1 by tying the rope to the bottom pulley instead of the bushing. It works fine for me that way too, even though it reduces the travel to 36". 2-to-1 does not work for me at all. Please let us know how yours turn out!
Thank you for the time you spent looking over my instructable. If you have read this far and are thinking, "This was great and totally worth a buck" You can help me continue to make more instructables by making a donation using this link to my ebay store. Thanks, and keep building! -- Yeltrow