9 replies to this topic

[Haynes]

On the n/s the wheel is practically touching the arch (12x4.5s).  So first stop is to fit new knuckle joints.

 

But before taking the car to bits, to practice on i have a couple of old trumpets lying around with the knuckle joints still stuck in them.  In trying to separate, tried plusgas, heating (with electric paint stripper) beating from the inside with a lump hammer and pointy cold chisel only to break the cone and the knuckle still stuck solid.

 

Any other advise please??  

 

They certainly became too hot to handle but maybe the heat source isnt enough.  

 

(Sensible answer is to just replace with Hi-Los but unfortunately really want to avoid this for insurance purposes.)

[Ben_O]

I usually clamp the ball of the knuckle tightly in a vice and then use a flat chisel on the collar of the trumpet down by where the knuckle presses in and knock it out with a lump hammer.

Never had any issues so far.

 

You may be lucky and find that the one on the car you are actually going to replace may come out easier?

[Haynes]

I usually clamp the ball of the knuckle tightly in a vice and then use a flat chisel on the collar of the trumpet down by where the knuckle presses in and knock it out with a lump hammer.

Never had any issues so far.

 

You may be lucky and find that the one on the car you are actually going to replace may come out easier?

 

Sorry, not quite visualising that. 

 

If the knuckle is clamped, are you hammering down, up or to the side?

 

Or are you cutting into the join between knuckle and trumpet?

 

If youre hitting the aluminium doesn’t it just break?  Doesnt the flare of the trumpet get in the way if the knuckle is clamped?

 

Apologies for being dumb but really want to get this if it works for you, thanks.

[Ben_O]

Just on the edge of the trumpet.

 

Struggling to find a photo on my laptop so I have a cropped zoomed in picture

 

 

red line shows where I strike.

It's a good idea to turn the lot in the vice so you can tap on the other sides too

[Haynes]

Excellent, thanks for going to trouble of finding suitable pic.

[MatthewsDad]

A long drift down the centre of the trumpet after a good soak in plus-gas.

[Cooperman]

Heat it up with a butane torch. The aluminium will expand more than the steel of the trumpet and it can then be drifted out.

[Spider]

I used to put the Trumpet through the Centre Hole in the Road Wheel to hold it, then take a length of 1/2" steel rod, drop that down inside it and tap the Knuckle out.

[DeadSquare]

To help loosen things, I find that it helps if I put the trumpet on something solid and hard like a concrete roadside curb stone, and with the ball of a hammer, hit the area with the knuckle in it, all the way round, hard enough to produce indentations so that it looks like Hammerite.

 

I clean the spigot of my new knuckle joint well with sandpaper, and stand it in a solution of copper sulphate for an hour to deposit a thin layer of copper on the steel before greasing it with 'Copperslip' and putting it into the trumpet.

 

I also drill a small hole through the trumpet at the top of the spigot, so that any water that gets into the trumpet can get out.

[Haynes]

Nope, just couldnt get it off.

 

For practice i continued with the trumpet that i'd already broken off the lip.  Whilst trying to tap out from the inside the end of the trumpet broke off.

 

So the second one I drilled out the centre and cut the steel joint off.  Had to that with a hacksaw as i didnt have any cutting disks.

 

Drill bit wasnt quite big enough so am finishing it off with a round file, its now become a battle of wills!

 

Not having a blow torch i guess doesnt help.