My SO and I own and ride tadpole trikes http://www.homemadetools.net/forum/t...8412#post53569 Hers is a Terra Trike with a front end that doesn't have sealed bearings on it like my ICE. It has brass bushings pressed into the steering knuckle. I'd been having a hard time getting the disk brakes to work properly without dragging. I noticed it had a lot of slop in the bushings and it finally decided it was time to tear into it. I also suspected that's why it didn't roll as freely as mine too as there was no way to do an accurate alignment. Here it is without the pivot pin.
After making the first bushing I realized the steering knuckle was not round so had to make the rest with a .003 press fit to make sure it was going not come lose ever again. I also left them .030 thicker to give a nicer fit in the frame. I put the bushings in the freezer for 20min and a little synthetic grease on the knuckle and pressed the bushings home. The knuckle pins are 12mm I guess as they were .470 and the closest reamer I had was 15/32 .468. Ended up filing down the pins to .467 as I couldn't wait for the adjustable reamer I ordered to show up. Now it was time to get a nice fit in the frame. I tried to think how to approach taking the .025 or so off the upper bushing, and thought WWOD? (what would Olderdan do? and decided to make an arbor for the lathe. One end is .467 for the knuckle and the other .5 to go in the tail chuck. I had a 1" worn out mill I'd inherited with my mill/drill and put it on the sharpener and put 3deg angle of cut on it with no 1deg dish so it wouldn't bite into the brass(hopefully). I also remembered what TM51 said about not chucking up the mill directly in the 3 jaw chuck and got out the arbor I also inherited with the mill/drill and mounted the mill in it and off I went.
I was able to fit each knuckle and install the pin and tighten it till everything moved freely with little or no slop.
For the first time I'm able to adjust the brakes properly and the alignment seems dead on. I've not gotten a side by side rolling test with the two trikes on a hill yet as that will be the true test. In the past if we started out even coasting mine would just pull away.
I also replaced the wheel bearings while in there and that proved to be an adventure too as they didn't see fit to provide reliefs in the bearing spacer to get a bite on the bearing to drive them out with. Along with a very finiky fit to make the bearings fit in the hubs with the spacer and then be tightened on the spindle.
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