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Most riders have no difficulty stopping their chair by gripping the handrims; consequently, a brake that will stop a moving wheelchair is not usually necessary. It is important, however, for for the wheelchair to have a parking brake. Without a parking brake that will hold the chair securely in place, it is difficult for the rider to get in and out of the chair. The parking brakes should be easy to apply. When engaged, they should hold the wheels very tightly. Brakes that hold the wheel by pushing against the tires should be designed to hold the tire securely even when the tire is somewhat low on air. |
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Our favorite brake is made from a bent steel rod that can be wedged against the tire. It is simple to make and the materials are inexpensive. The brake is bent out of steel rod about 5/16" diameter (8 mm), and it pivots in a hole through the frame. The brake is engaged by pulling it back, pressing it against the tire, and slipping it over a metal catch mounted on the sideframe. The brake will remain engaged until it is pulled out from the catch. Even paints that adhere well to the metal are easily scratched off on the brake; consequently, the brake is another one of the parts of the chair that is best protected from rust by having it plated. |
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MATERIALS
| ITEM | QUANTITY |
| 5/16" (8 mm) plated steel rod | 2 pieces, 18" (45.7 cm) long |
| 1/8" (3 mm) diameter cotter pins | 2 |
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JIGS OR BENDERS
Directions for making the jig can be found in Appendix B. Both the jig and bender can be purchased as part of the Basic Tool Kit. DIRECTIONS1) Measure and mark the rod to indicate the bends.
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4) Bend the rod 90~. Check the bend with the angle-measuring tool and compare it to the sample brake in The Basic Tool Kit and/or to the full scale diagram at the end of this chapter.
5) At mark #2, bend the rod 90~ in the opposite direction. (Remember to be sure that the last bend is level in the bender, and that mark #2 is 1/8" (3 mm) behind the point of the bending dog before beginning the bend. |
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6) At mark #3, bend the rod back on itself forming a 180~ angle.
7) At mark #4, bend the rod 90~ in the opposite direction. The bent rod must lie on top of the eyebolt bending dog for the bend to be in the right place. As you may have guessed, this will give you a crooked brake. Cutting off the part of the flat-head pin that sticks above the eyebolt bending dog may help a bit. Don't worry that this bend will result in a curved brake. After the brake has been made, the left brake can be fixed easily and the right brake will work as is.
8) Place the bar in the bender as shown, and bend the end of the handle 20~.
9) Turn the rod over (180~) and position it in the bender as shown. At mark #5, form the brake handle by bending the rod more than 180~ until it touches itself.
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10) Both brakes will end up curved. The right brake can be left as is. The left brake must be straightened out and bent in the opposite direction to look like the brake in the diagram. |
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11) Slip the cotter pin hole drilling jig over the end of the brake as shown. Clamp it in place in the drill press vise, and drill a 1/8" (3 mm) hole. |
| 12) Weld two reinforcing washers with an inside diameter of 5/16" (8mm) over the brake mounting holes that were drilled in the sideframes ahead of the X-braces. If washers with these exact hole sizes are not available, buy smaller washers and ream them out to the right size. |  |
13) Mount the brakes through the brake mounting holes. Once you are sure that the rear tires are properly inflated, check the adjustment of the brakes. The brakes should dig into the tire about 1/4" (6 mm) when they are locked, but locking the brakes should not be difficult. Remove the brakes and bend them in a vise until they are well adjusted. When completed insert the cotter pins to hold the brakes in place.
