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Tight crush tubes
bodger - 2/2/07 at 10:43 PM

OK, OK I've done the searches & read the threads so don't want to start world war 3 BUT:

My crush tubes are REALLY tight inside the PU bushes. The bushes themselves took quite a bit forcing into the sleeves using a vice. Running along the length of the sleeve is the weld line from the tube manufacturing process, this seems to be distorting the bush somewhat.
Should I

a) File the weld line smooth to remove the deformation or am I likely to end up with the bushes rotating in the sleeve?

OR

b) Ream out the bushes to free up the crush tube.

OR

c) Do nothing & see what happens after a few miles on the road.


locoboy - 2/2/07 at 10:48 PM

Option C

Then if not loosened its self up look further at options A and B


ProjectX - 2/2/07 at 10:50 PM

Just wondering why you have a weld line in your tube?? Are you not using CDS for the bones?

J


locoboy - 2/2/07 at 10:59 PM

Most people and manufaturers dont as as far as i know................

Or am i missing something????


stevec - 2/2/07 at 11:10 PM

If the weld line is deforming the bush that has to be wrong,
I would first clean up the bore.
Steve.


PAUL FISHER - 2/2/07 at 11:10 PM

Answer C.

The tubes should be a tight fit on the bushes,in order they don't spin within the bush,the join/weld in the tube helps this,just ensure you apply a bit of grease on the bolts when your building them up.


stevec - 2/2/07 at 11:34 PM

quote:
Originally posted by PAUL FISHER
Answer C.

The tubes should be a tight fit on the bushes,in order they don't spin within the bush,the join/weld in the tube helps this,just ensure you apply a bit of grease on the bolts when your building them up.



If the bolts are tight and the inner steel tubes are held firm by the clamping effect,
What is the grease on the bolt doing?


Chippy - 2/2/07 at 11:40 PM

PU bushes are not affected by oil or grease, so you can give them a good coating to assemble. Deflex recommend you put one side in, then insert the other side with the crush tube half way in. Then push them together in a vice, with the crush tube in. Put a spacer on the other bush, so that the crush tube can go through. Hope that makes sense, and HTH. Ray


bodger - 2/2/07 at 11:52 PM

Here's a picture of my bush he! he!


wishbone sleeve
wishbone sleeve


[Edited on 2/2/07 by bodger]


PAUL FISHER - 3/2/07 at 12:09 AM

quote:
Originally posted by stevec
quote:
Originally posted by PAUL FISHER
Answer C.

The tubes should be a tight fit on the bushes,in order they don't spin within the bush,the join/weld in the tube helps this,just ensure you apply a bit of grease on the bolts when your building them up.



If the bolts are tight and the inner steel tubes are held firm by the clamping effect,
What is the grease on the bolt doing?


Just to ensure you can still remove them at any time,the steel bolt and the steel bush,even after 12 mths of british weather could be rusted solid.
The important point as Ray says above plenty of grease,and also keep checking each wishbone as you fit it,to ensure it moves up and down freely,with no play,and no anoying squeaks!

[Edited on 19/05/04 by PAUL FISHER]


macnab - 3/2/07 at 12:11 AM

Yeah that pic fits real well on to my 10ft screen...

Well you can see the problem can't you, that weld is the cause. Quick cure file a slot in the bush to accommodate the weld line and that will also stop the bush from rotating.

Damn fine piece of advice that

[Edited on 3/2/07 by macnab]


PAUL FISHER - 3/2/07 at 12:31 AM

Thats better


907 - 3/2/07 at 12:43 AM

Beeeeeeeeeeeeeeeeeeee


Paul G


Avoneer - 3/2/07 at 09:24 AM

Yep - loose the bloody seam...


blueshift - 3/2/07 at 10:50 AM

I'd go for the "file a slot in the bush" option myself. unless you have a lathe handy.


JoelP - 3/2/07 at 11:07 AM

id leave as is. One way or another it has no chocie but to rotate somewhere. Theres no way that that seam is going to provide enough resistance to bend bones or any other such dire failure.

At least the bone is made properly, with the seam covered by the leg of the bone, so if you do file it out you dont risk weakening the structure overall.


907 - 3/2/07 at 12:58 PM

Hi All,

I had a similar problem with tight crush tubes in my stainless bones.

I made my bush tubes in the lathe and the bushes were a nice fit inside them
until I welded the U shaped tube to the bush tubes.
The welding caused the bush tubes to shrink so the bushes became a tighter fit.
I then had to fit them by squeezing them in, using the vice.
I think this caused the I/D of the bush to shrink making the crush tube a tight fit.

Stainless shrinks more than mild steel, hence my problem, but the seam in the pipe
could do a similar thing. The material has got to go somewhere.

My cure was, after fitting the bushes, to ream using in my case, a 9/16" drill.
I did this on the lathe. The drill in the chuck, and a 9/16" short shaft in the tail stock.
By sliding the bone onto the t/s shaft a few mil, the other side held up to the drill in the chuck,
and then turn the chuck by hand.
Turn the bone round and do the same the other side.
This kept the two sets of bushes in perfect alignment.

It only took out a tiny amount but it was enough to make a big difference.

If I didn't have a lathe I would screw a drill or reamer in by hand.
I also would not have a problem with grinding out the weld seam.

Hth

Paul G


rusty nuts - 3/2/07 at 06:51 PM

Had a similar problem with my Luego. After a year on the road finally got fed up with the squeeking every time the suspension moved . I dismantled every suspension arm on the car and used a dremel type tool to remove the excess weld and also put the bushes them selves in the lathe and skimmed the top hat section so that when the crush tube was installed and nipped up in a vice the arm could rotate around the crush tube . Longer crush tubes would have been better but as I did the job on a Sunday I wasn't able to get any stainless. Finally assembled giving all the bushes and crush tubes a good coating of rubber grease. The result was no noise and a much smoother ride . Contrary to some opinions the retaning bolts should be tight and nip the crush tube and everything rotates around it


bodger - 3/2/07 at 08:40 PM

Thanks guys, haven't got a lathe so I'll probably file out the seam or put a channel in the bushes. Bit of a pain in the a*se though, wish they'd used seamless tube.