Slide pins question! Have I shafted my carriers?

[mattnorgrove 0]

I'm in the process of rebuilding a set of 288's, had them sandblasted last week, and have painted them up. The guy who did the shotblasting told me they'd been through a parrafin bath afterwards, so all's ready to rebuild, or so i thought. Tried to refit the slider pins/boots after cleaning them up and greasing the pins (used a regular grease for this). The longer two pins seemed really reluctant to go back in, felt like it was just too big for the hole. :grin: The shorter pins with the rubber end sleeve type thing go in fine.

 

So the thought struck me (too late I fear), that the slider pin hole may still have some grit from the blasting in it (dont think those holes were masked off) :| so ive given the holes a good blast out with Gunk Ultra to shift the grease i'd put in, and took them to be blasted out with air.

 

Had a good look with a penlight after i'd blasted them out, and the inside of the hole for the slider pin looks rough to me, and the pin itself (was unmarked before trying to refit) now has scoring marks on it.

 

Have greased it up again and refitted following the air blasting but the pin seems really sticky/stiff but does move with a little persuasion.

 

So a few question's: Have i fooked the carriers/pins, and just how smooth must the sliding action have to be?

 

(if anyone could explain the sliding motion too, and what purpose it serves would also be grateful, i'm a complete noob when it comes to brakes) :(

 

Why are the pins different lengths, and which should go in which hole?

 

Please help guys!!

 

:(

[mattnorgrove 0]

Anyone? :(

[davidwort 0]

caliper has to slide on carrier as the piston presses on one side of the disk/pads only, the outer 'claw' of the caliper pulls the other side/pad and is obviously 'fixed' as opposed to the piston moving.

I can't actually remember the 'inside' drilling where the pins go, but I'd imagine they need to be pretty perfect to allow smooth even movement of the caliper.

[mattnorgrove 0]

Thanks for the reply David, I can see what you mean now I've put the calipers/carriers together.

 

Need to find some kind of cylinder polishing tool I reckon, and smooth off the inside of the cylinder the pin slides into (and smooth the pins too). :(

 

Thanks again...