How much clearance for these bushings?

[80 MONZTA]

I am making my own steel greasable lower bushings like the pic below. How much clearance should I make where it pivots?

[MrQuick]

you going full metal? average is .005-.009in ra you can run delrin abit tighter

[80 MONZTA]

Yeah, full metal. Thanks for the average, never made anything like this before. First set is at .004, so I will open them up a bit.

[Rod]

let us see the first set?

[JRouche]

Cool!! I thought I was the only one messing around with making metal bushings. I made some, for the front. I started out with some 4140PH bars. It turned pretty good, not as nice as 4140 annealed.

They were solid bars so I had to take alot out of the center. I drilled them out to minus .150" then bored the remainder out to within .001" for my ending number of .005" of clearance. I made the bushings (inner and outer shells). The hard part for me was getting a decent .001" for the entire bore. I was able to get a decent .001" dimension for the inner part of the bushing. Outside turning. But getting the bore of the outer part of the bushing was time consuming. But I got the fitment to .005" throughout for all four bushing parts (I only needed the lower bushings)..

Good to see some other folks making their own parts.. JR

[MrQuick]

Yeah, full metal. Thanks for the average, never made anything like this before. First set is at .004, so I will open them up a bit.

Problem is if you are not machining your own parts the tolerances will push it to tight or just be so wide.

Vince

[monteboy84]

Man, .005-009" seems like a bunch. When I'm designing around a bushing, .001" clearance per 1" of diameter is the rule of thumb. I'd keep it at .004" if it were me, but if other bushings are going .005-009 I suppose they have a reason. Only thing is, the main reasons for bushing clearance are lubrication, and misalignment of components, but in a case like this, the mounting bolts are able to take a whole bunch of misalignment versus what a loose bushing fit will get you.

-matt

Edit: When I say bushing here, I'm using it interchangeably with sleeve bearing, in case there's any confusion/misunderstanding.