Lathe - make bushing sleeves

[mikeatrpi]

I am adapting Nissan 300zx polyurethane subframe bushings for use on my 1982 280zx. The primary modification is to turn down the outside of the bushing to fit the smaller diameter of the 280zx's subframe. My question is related to the sleeve that goes inside the bushing. The ID of the 300zx kit sleeve is 0.861". The ID of the stock sleeve is 0.836". The OD of the bolt is 0.794". I'm trying to decide if I should make a new sleeve on my lathe with a tighter ID to fit the bolt better - what do you think? If I do, is aluminum OK or should I make it out of steel? I don't know if my machine has enough gumption to cut stainless.

Here is the guide I'm following:
http://www.zdriver.com/forums/280zx...1/polyurethane-subframe-bushings-maybe-19834/

Here is a pic of the subframe bolt on the 280zx (top). Note the funky shape. Any ideas why its shaped like this?

Thanks!

 

[racingtadpole]

Make it out of Ally and the bolt will eat the bush, make it out of stainless and the bush eats the bolt. I would make them out of steel and then have them plated to help keep the rust at bay.

Your picture link isnt working.

 

[mikeatrpi]

Thanks for the tip - that makes sense.

Sorry about the pic... here's the full link. Pic is 2/3 down
http://www.angelfire.com/extreme/280zxt/page17.html

 

[bad_idea]

How about making a custom bolt? Turn down a larger bolt to have the size shoulder you need for the bushing and then cut threads on the portion that extends outside of the bushing. If your lathe will not cut threads, then you can cut the threads with a die nut.

 

[Steevo]

Using it without a different bushing or bolt is a little too sloppy, and will move too much.
You can buy bushing material from McMaster Carr, or Speedy Metals pretty inexpensively, and finish the ID and OD to your desired dimensions easily using a lathe.
bore the center, then turn the outside, then cut off to desired lengths.

http://www.speedymetals.com/c-8242-round-tube.aspx?pagenum=2

 

[racingtadpole]

Here is a pic of the subframe bolt on the 280zx (top). Note the funky shape. Any ideas why its shaped like this?

To allow a small amount of misaligned loading.

 

[Zeke]

.060+ doesn't seem like too loose to me. You want some grease on that bolt/sleeve, right? If you're gonna go for the tight fit, you might want to consider a bronze alloy. IIRC, the hot rod suspension I installed a few years back had lubricated bronze sleeves inside the urethane bushings. They were snug. But due to the type of suspension, they ID was much larger as well. Still... is it silicone bronze I'm thinking of?

 

[rbgearz]

Oilite would work well for bushings. Just don't get them too hot while turnig them or you'll lose the oil in them.

 

[rsanter]

Take the right thickness of sheet metal or copper sheet and roll a sleeve that will fill the clearance between the original bolt and the replacement sleeve

Bob