Low friction material for a bushing

C-Bag said:
Delrin and UHMW are not the same material at all. The wiki on UHMW is very interesting......
Click to expand...
I have worked extensively with UHMWPE. It is very durable and wear resistant. Plastic cutting boards and the bearing part of artificial hip joints are made out of it. It is so tough that it lasts for years in situations that would wear out hardened steel in weeks. That being said, it is fairly soft but has pretty good memory. Its wear resistant properties make it an ideal candidate for rough condition seals. Delrin might be a consideration. It is easy to machine to high tolerances and has self lubricating properties but does wear and can shatter under extreme impacts.
 
SamI said:
Hi guys,

I’m a keen mountain biker and I’m getting fed up of the bushings in my rear shock wearing rapidly. Well, I don’t mind them wearing but they are quite expensive! This got me thinking, why not just make some myself and keep a bunch in the drawer so I can swap them out as needed?

So my question is, what to make them from?

The existing ones on my bike are a plastic bushing that is pressed into the shock with an aluminium shaft running through it. I have seen some people run a brass shaft (I’d probably prefer bronze myself) through a plastic bush but is there any merit in running two bearing materials against each other?

The ultimate aim would be to reduce friction as the difference can be noticeable when out on the bike (I used to run needle bearings but these seemed to come out of the box with a little play which worsened rapidly. they did make the suspension much more supple though).

I was thinking a plastic DU bush and a bronze shaft but if there won’t be any improvement over a steel shaft then I won’t bother with the added expense. I was thinking D2 tool steel hardened to somewhere around the 52 HRC mark if not bronze.

Any help would be greatly appreciated!
Click to expand...



Try Vesconite, its a hi load plastic used for bushings on excavator buckets, I've used it for pumpshaft bushes as its swelling is near zero immersed in water. It'll last you for years, can't see you wearing it out. It is expensive. Machines beautifully even with carbide provided you use positive raked sharp edges.
Made in south Africa I think, but your local power transmission shop should be able to get it/have it.
cheers
 
Last edited:
fitterman1 said:
Try Vesconite, its a hi load plastic used for bushings on excavator buckets, I've used it for pumpshaft bushes as its swelling is near zero immersed in water. It'll last you for years, can't see you wearing it out. It is expensive. Machines beautifully even with carbide provided you use positive raked sharp edges.
Made in south Africa I think, but your local power transmission shop should be able to get it/have it.
cheers
Click to expand...
Thanks for posting that. Very interesting stuff. There is discussion elsewhere about using Vesconite instead of Turcite or Roulon on slideways and it seems cheaper, tougher and easier to scrape in because of that. And it can be glued into place with their two part epoxy. Sounds ideal except you have to order it from S.Africa.
 
Ed ke6bnl said:
check out Vesconite I am running them as link pin spacers for my offroad buggy kinda expensive stuff. the other I have used is a nylon with moly impregnated into the material. I am no expert but this has worked for me.
Click to expand...
The nylon you mentioned is sold as GSM around here. Greate stuff. I am very impressed with it. I make bushing for a client of mine that they use on their 15to tippers. At first I did not think it would last,but I made a few now and none of those I made over the last two years or so has come back for a change of bushing. In fact I just made some this past week. So if this is the same product you have there,I can highlyrecommend it.
 
C-Bag said:
Thanks for posting that. Very interesting stuff. There is discussion elsewhere about using Vesconite instead of Turcite or Roulon on slideways and it seems cheaper, tougher and easier to scrape in because of that. And it can be glued into place with their two part epoxy. Sounds ideal except you have to order it from S.Africa.
Click to expand...


I would do a search locally of bearing or power transmission dealers around the place and see if they stock it.
I would be surprised if no-one in the US stocked it.
When reading the start of your thread you mentioned adjacent bearing materials.
You should have a harder pin or shaft than the actual bush because the bush is designed to be sacrificial.
As mentioned above nylon is an abrasive material in my experience, i would stay away from that.

Cheers Alby
 
Fromm an engineering point of view I would use a SS shaft or hard chrome plated with any of a number of hard engineering plastics like UHMW , but there are many others often marketed under different brand names, but essentially the same. this will work very well if wet with clean water, but if mud and dirt are involved I would try to fit "O" ring seals as others have mentioned. You might also look at a hard polyurethane bush, these can be molded rather than machined so you can make a small die and mass produce them. these are widely used in off road vehicles suspension.
 
Hi there, it has been some time now since I visited this forum. I read your post with some interest. As your post is dated Jan 2019, you may very well have solved your "bushing" problems by now. However I thought that I would mention to you, a product in south Africa that has phenomenal properties for many applications, one of which is "Bushings". I have used this product many times with excellent results. If I knew how to attach their brochure to this page I would have. I have removed Vesconite bushes and replaced them with this product. It is called PRATLEY MOULD. It is made by Pratley who make a wide range of adhesives. You purchase a Kit which comprises of a small box, that contains three tins of "liquid stuff" you mix the contents of theses tins together and pour the mixture into a mould. I usually mould rods of what ever diameter I require for bushes I make. I use PVC electrical conduit pipes for small diameters or PVC plumbing pipes for lager diameters of 2 inches or so. The local price of this product is R217.30 SA for the Kit which is $15.00 US.
The kit weighs 1.36kg which is 3lbs, the total mixture produces 1.1 litre, aprox 2.5 pints (I think) This product is super tough and it machines beautifully. I have cut threads on it, grooved and milled it. I still had pieces that I moulded 10 years back, it does not perish. their website has brochures that explain in full.
www.pratleyadhesives.com, (or .co.za ) look for the Industrial adheasive tab

Regards Basil
 
You must log in or register to reply here.
Back
Top