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Delrin for bushes
Avoneer - 5/12/05 at 09:58 PM

Can you use delrin to make your own bushes?

Pat...


Triton - 5/12/05 at 09:59 PM

As in wishbone things?.......why when they are so cheap and easy to get from MK, Mac#1 etc


paulf - 5/12/05 at 10:13 PM

It is to hard for wishbone bushes on a road car , but ideal for pedal bushes etc and very easy to machine to a nice finish..
Paul

quote:
Originally posted by Avoneer
Can you use delrin to make your own bushes?

Pat...


Genesis - 5/12/05 at 10:44 PM

I always find 'seeds' are the best way to make bushes - depends what you want but Leyllandi is one to avoid


andylancaster3000 - 5/12/05 at 11:03 PM

We've just bought a load of molybdenum disulphide loaded nylon 66 from RS. (Not a chemist myself so please dont ask )
Although I believe that it has a little more 'give' than other forms of nylon with very good wear properties. Suitable for wishbones but not for axle or panhard applications as these must be compliant.

HTH
Andy.


andylancaster3000 - 5/12/05 at 11:06 PM

I also believe that polybush companies such as Powerflex sell their bush material by the foot with instructions on how to machine the stuff. May be worth investigation...?


liam.mccaffrey - 5/12/05 at 11:21 PM

you have to put it in the freezer i think


Avoneer - 5/12/05 at 11:50 PM

quote:
Originally posted by Triton
As in wishbone things?.......why when they are so cheap and easy to get from MK, Mac#1 etc


Yep, as in wishbone things.

Well, for my trailing arms actually as they have a funny sized eye and I think it would be cheaper to get some machined than have to buy some.

Pat...


Peteff - 6/12/05 at 12:14 AM

Trailing arm bushes need to flex sideways a little bit, which is what delrin doesn't do, you need poly bushes which are a bit softer to absorb the stress and return to their original shape. PU is usually cast in rubber moulds, not machined I think due to it's characteristics like inability to conduct heat causing it to melt.

[Edited on 6/12/05 by Peteff]


timmy - 6/12/05 at 02:09 AM

Delrin is too brittle for suspension bushes. Nylon is good for wishbone bushes, but you need to make sure everything is aligned because it has no give.
The MDS impregnated stuff would be ideal if a bit hard for road use (no worse than rose joints, though).
Polyurethane can be machined if you know what you're doing. Freezing would help, but I suspect liquid nitrogen would be better than just chucking it next to your frozen veg.....

HTH,

Tim


Syd Bridge - 6/12/05 at 09:05 AM

quote:
Originally posted by Avoneer
Can you use delrin to make your own bushes?

Pat...


Yes, you can. But better to use Nylatron, or molydisulphide impregnated nylon66. Used all the time in racing, for all sorts of things.

It can only be used when movement is in a single plane, and the bush axes HAVE to be lined up perfectly.

This has all been said before, but as above, best to use polyurethane.

Syd.


big_wasa - 6/12/05 at 08:48 PM

Is molydisulphide impregnated nylon66 the same as nylon66 ?

Have seen this for sale on ebay and its put ideas in my head ebay link good reason to do a bit on the lathe me thinks.

What grade of stainless steel do I want for the center bushes ?

regards


timmy - 7/12/05 at 12:53 AM

The difference is the MDS....

Nylon 66 is just the polymer. They add stuff to it to alter it's properties. That's where the MDS comes it.
If I can recall from my plastics days, the oil/lubricant impregnated nylons are generally a bit softer but slide much nicer (as you might expect).
Nylatron is just a brand name of a specific grade of nylon that has (i think) MDS in it.


andkilde - 7/12/05 at 03:14 AM

I'd be careful with Nylon as a suspension bush -- it swells when exposed to water. Plain nylon swells up to 10%, not sure about Nylatron.

PU is machinable, room temperature for 85a or above, frozen for softer. It requires tools with more rake than metal.

Cheers, Ted


DEAN C. - 13/12/05 at 08:39 PM

Hi,about 7 years ago I made Bushes in fairly large quantities which i sold through a local Land rover independant dealer.

These were mainly panhard bushes for heavy diesel conversions and V8 racing applications.

I always used Nylon 66,I also raced on these bushes finding that on the front panhard rod they improved the feel of the steering quite a lot,and I never heard of them swelling in any fluids.

You do need a steel inner bush though as a few we tried for racing (as an experiment before I sold them to customers)without and the bolt straight into the nylon, wore the bolts as well as the bush!

I found that a couple of thou oversize was enough to grip inside the rod end,leaving a slightly coarser finish to help grip as well.

If you are machining Nylon 66,as fast a speed as possible is needed,plenty of rake on your tip and water or parrafin is ok for coolant(i used plain water)not coolant!

[Edited on 13/12/05 by DEAN C.]


big_wasa - 15/12/05 at 07:45 PM

Ta just what I wanted to know


chrisf - 15/12/05 at 07:50 PM

I used Delrin bushes and had them custom machined. They turned out nicely. I haven't driven with them, but hope they work well.