Introduction: Kayak Cart Made From a Bob Jogging Stroller
Inspired by another instructable to build a kayak cart from a jogging stroller I found that Bob brand strollers were plentiful on Craigslist and with some hunting and waiting could be found for a reasonable price. I have built 3 of them from different models. The photos and build instructions are for the second cart I built from a stroller that had the parking brake option. If possible I recommend you try to find one with a parking brake. Otherwise you will need to block the wheels with 2x4 pieces of wood front and back to hold it still when loading.
First remove the stroller fabric, seat and shade stays. These are held on with screws. You may want to cut the loops around the brake cable, but you do have to unscrew and remove the front brake assembly and the brake lever on the upper rear cart handle.
Next pull on the loop connecting the 2 shock absorbers and push-pull them down into the lowest position. You can then remove the cable connecting them. You may want to remove the wheels before the next part. Just pull the levers, you may need a screwdriver for leverage as they can be tight.
Next place a 1.5 inch 10/24 bolt or screw into the lowest hole closest to the shock absorber mount. Using the washer and a nylock nut, screw it onto the screw/bolt as this will keep the shock absorber locked into the lowest position. I found out they sometimes move and if the cable has been removed it is hard to push them back.
Remove the front tire and flip the frame over. You will need to drill out the rivets holding the rear axle mount onto the frame posts because you need to cut the frame lower. The reason you need to lower the frame, and I found out the hard way is that at the original height the cart is top heavy, unsteady and it wants to tip over at the slightest bump.
Use a quarter-inch drill to remove the rivets. First, drill it so the top cap comes off for each side of each rivet. Then go back and drill all the way through to remove the inner portion of the rivet. Make sure your ¼ inch bolts will fit.
Now you need to determine how much to cut from the frame. On this one I cut off 5 inches and found it left enough room to clear the black round handle at the end of the shock absorber mount. Use a hand metal hacksaw or a metal blade on an electric jigsaw. File off any rough edges.
Test fit the axle mount, I used a rubber mallet to help it into place. When drilling the new holes drill each side separately, going in through the hole in the axle frame. Once you have drilled through from each side, then push your drill through to the other side to check alignment and sizing. Install a wheel to check the fit. And that it clears the shock mount knob. Make sure your ¼ inch bolts will fit. You will need 4 bolts size 1/4 inch coarse thread 2.5 inches long. Get some washers to use on each side and nylock nuts to hold it together. The local orange home D store has all of these materials.
On my first kayak cart which was a different stroller model, I cut off 8 inches and had interference from the shock absorber mount knob. I had to cut the knob off with a hacksaw. This only took a few seconds. You will not need to use that knob and the screw you added holds the shock in position.
On some cart models you can leave the front tire on and use it to balance the cart from tipping when loading. On other models you need to remove the tire and attach a length of wood to the front end. If you removed the wheel you may be able to use the brake mount hole to insert a 2 or 3 inch bolt into a piece of 2x4 about 15 – 20 inches long. Wood length is best determined by trial and error depending on your preference.
For the rear stabilizer piece I just drilled a hole through the frame and inserted a similar bolt into another piece of wood. I happen to have a box of old oak flooring so used that as my stabilizer. Tilt the cart down to check alignment for the rear piece as the required angle is different as the cart tips down.
The next part is fitting the pipe wrap around the frame to pad it for your boat. Get 1 inch diameter pipe insulation. It comes in 6 foot lengths at the big box hardware store. You will need 2 of these pieces for your cart. Also some 11 inch zip ties to hold them onto the frame in place. You will be covering them with duct tape which protects the foam from tearing as the kayak slides across it and is much lower friction than the foam, making it easier to load and unload your boat. The zip ties mostly keep the foam from rotating and hold it in place in a few sections that are under more tension. Note that I doubled up the foam on the transition section where the upper cart handle meets the lower handle and there is drop off as the both insert into a plastic piece.
If you do find a Bob Stroller with the parking brake, pay close attention and photograph how the parking brake assembly mounts and which way it is situated on the axle before taking it apart. You will not remember when you go to put it back together!
Get some hold-down straps and you are ready to load and roll your kayak to the water. I run the straps through the area that is sort of a center triangle shape by the shock absorber. This keeps it from sliding up or down the frame. Have fun building this and safe paddling out there!
You will need the following:
4 bolts 1/4 inch x 2.5 inches coarse thread, plus washers and nylock nuts to hold them together for the axle frame.
2 bolts 10/24 1.5 inches long, plush washers and nylock nuts to hold the lower shock mount in place.
2 machine screw bolts size about ¼ inch for the stabilizer wood pieces.
2 pieces of 1 inch inner diameter foam pipe insulation to wrap the frame.
11-inch zip ties to hold the pipe insulation in place.
Duct tape to cover the pipe insulation.
Screwdriver, rubber mallet, metal hacksaw or jigsaw, wrenches and or sockets.
Electric drill and ¼ inch bit.
If you have the parking brake you need to drill out its rivets to remove it and then drill new 1/4 inch holes through the rails from the side to mount the parking brake after you have cut it down and mounted the axle assembly. Looking at the holes on the piece you cut off, drill new holes in the same position near the axle assembly. Make sure the brake and axle are lined up properly facing the rear of the cart. Use 1.5 inch long, 1/4 inch bolts, washers and nylock nuts.