Swinging arm bushes

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B44Claus
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Swinging arm bushes

Postby B44Claus » Tue Nov 28, 2017 1:21 pm

Gents,

Before performing some repair weld to the swinging arm on my 69 Starfire I removed the silentbloc bushes from the swinging arm. Rather than installing new silentblocs I'm considering if I could install brass or bronze bushes instead? That would also save me the work with removing the outer tubes for the silentblocs which are still inside the swinging arm.
My idea was to have some bushes turned from brass or bronze and then glue them in place with epoxy. Reaming them to a nice fit with the spindle could be done with the bushes glued in place.

What do you think, - will that work and if no why not?

Brgds,
Claus
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Re: Swinging arm bushes

Postby minetymenace » Tue Nov 28, 2017 1:47 pm

Hasn't the silent block outer sleeve got little bits of rubber still bonded to it? Why not take the outer out, it would give you a truer hole to sleeve. Have you seen commando's words of wisdom in this topic?

Did you get your swing arm straightened Claus?
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Re: Swinging arm bushes

Postby B44Claus » Tue Nov 28, 2017 2:37 pm

Hi Minety,

I actually burned out the old silentblocs with a large propane torch. The rubber melts and burns and the silentblocs sort of creeps out by them selves and shall just be wriggled out the last few mm with a pair of pliers. I strongly advice you to undertake this whole operation outside!
The rubber that remains in the outer silentbloc sleeve can easily be removed with a steel brush on a drill.
Yes I did look up the wise words from Kommando and also considered the needle roller conversion but decided to investigate bronze/brass bushes firstly.
Really I have never quite understood the purpose of the silentbloc bushes with rubber bonded between a outer and a inner sleeve. My 50's B33 had them as well and they seem to last well but are a pita to remove. Why not just a metal sleeve that can be replaced easily?
I had to remove mine as I needed to repair weld the swinging arm near the pivot and would spare my welder friend from lung edema.
The outer sleeve appears to be true and I think a metal sleeve/bush can be fitted directly to it.

Brgds,
Claus
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Re: Swinging arm bushes

Postby B44Claus » Tue Nov 28, 2017 2:40 pm

Yes, I had to straighten the swinging arm after welding. Again my propane torch came in handy :grin:
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Re: Swinging arm bushes

Postby kommando » Tue Nov 28, 2017 9:48 pm

I fitted needle rollers but the outer sleeve needs to come out.

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Re: Swinging arm bushes

Postby B44Claus » Wed Nov 29, 2017 9:20 am

Hi Kommando,

Thanks, - yes I noticed that from your well described swinging arm needle roller conversion.
I'm following a different path where I will fit metal bushes as replacement for the silentblocs and if I don't need to remove the outer sleeve I will leave it in place. It appears to be a very tight fit in the swinging arm anyway.

Brgds,
Claus
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Re: Swinging arm bushes

Postby kommando » Wed Nov 29, 2017 9:14 pm

It's a tight fit but thin and prone to rust, you could hacksaw a slit and it should come out. The A65 in 70 went from metalastic bushes to bronze bushes so worth looking at the parts book to see if those parts can be used or adapted.

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Re: Swinging arm bushes

Postby B44Claus » Mon Dec 11, 2017 11:31 am

Thanks Kommando,
Good idea with the A65 bushes!
However, from what I could find the A65 bronze bushes are too thin to fit inside the B44 S/A so I guess I'll have to turn a couple of special bushes with the right dimensions.

Brgds,
Claus
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Re: Swinging arm bushes

Postby B44Claus » Thu Oct 11, 2018 2:14 pm

Hello,

Just to conclude on this topic about swinging arm bushes in my B25 Starfire:

I had a friend turn some brass bushes for me in his lathe
B25 Bushes_1.JPG

The outer sleeve from the old bushes were left in place as I didn't see the need to remove them. Actually, one of them had been welded to the swinging arm when it was repaired.
The outer diameter of the new bushes were machined to a rather loose fit to allow for gluing with two- component epoxy.
After fitting the bushes but before the glue hardened I installed the spindle in order to align the bushes
B25 Bushes_2.JPG

I was careful to adjust the distance between the bushes to ensure the width was correct and a good fit in the frame.
I have installed the swinging arm in the frame, time will tell if this repair will last.

Brgds,
Claus
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