The windshield wiper blades on the bus are in very bad shape and hardly move around the water on the windshield at all, as I experienced this morning on the way to the dump.
The bus blades use a different means of attaching to the wiper arms than do standard automotive blades. The bus wiper arms each have a hole in the end and a large, ridged washer welded to the blade side of the arm.
The blade attachment mechanism has a captive bolt that goes through the hole in the wiper arm and an acorn nut to hold it in place. The bolt both holds the blade on the arm and — through friction with the ridged washer — sets the angle between the arm and the blade (which need not be colinear).
I think if I removed the welded-on washer, the wiper arm might fit the clip on a standard blade, without this mechanism. That would eliminate the ability to set the angle of the blade, though; and I do have the blade at a slightly different angle than the arm. I may consider knocking off the washer in the future, rather than continue to modify standard wiper blades.
(My local) Autozone doesn’t have wiper blades to fit the bus attachment type, so I modified a Rain-X blade. Mr. Negative at Autozone suggested duct tape and said no matter what I did it would look stupid. I believe the psychological term for his behavior is “projection.”
The first step was removing the stock clip that snap-fits onto the center post.
Then I cut and removed the post.
The post’s holes were just the right size for the bus clip’s blade-to-clip bolt. I tightened the nylon-insert lock nut enough to squeeze the new blade’s walls down almost to the width of the bus clip, to reduce lateral and angular play.
The modified blade fits and works perfectly. Stupid indeed.