Bearing saver size

[Nasher]

I've used Bearing Savers on my boat trailers for years, and am convinced they work.
I've hardly ever had to change a bearing due to water ingress.

I've got a new pair of axles sat waiting to go under the trailer.
It's a pity the Bearing savers aren't Bearing, Back plate, and Brake component savers!

The new axles are based on Knott hubs, and having tried them today my current 50.25mm Bearing savers are a loose fit inside the brake drums, which is of course useless as they need to be an interference fit to knock in and stay there.

I've measured the holes they fit in at 50.40mm.
The only bearing savers I can find online that are not 50.25mm are either 50.50mm or 50.73mm, and are aluminium rather than the Chromed steel of the old ones.

Bearing in mind they are Aluminium and will need to be knocked in and out every time I strip the hubs to clean the brakes etc I'm not happy that 0.1mm is enough of an interference fit, but 0.33mm is too big.

I'm tempted to buy the bigger ones and skim them down to @50.60 in my lathe.
But being Ali they will soon loosen up too much after a couple of times going in and out.

Does anyone have any experience of the tolerances used by the manufacturers for Aluminium ones?

My other option I suppose is to strip the guts out of my current ones and make some new housings in Stainless, but that's a lot of cutting Stainless with a boring tool in my lathe unless I can find some thick wall tube of a slightly bigger diameter to turn down.

.

[Steve509926]

Hi Nasher, never used bearing savers, but could they not be made an interference fit by wrapping with PTFE tape?

[beerbelly]

mine has the alloy ones supplied by de graaf no springs inside either just a grease nipple and a small hole that shows its full by a tiny squirt of grease coming out they have been on since 2015 been knocked on and off loads of times and are a little dented and battle scared but still secure and working fine .i change my bearings every other year and have never took a set out that actually needed changing.hope that helps

[beamishken]

I've had the same issue trying to find a replacement bearing saver & struggling to find the exact size. I found they were either too small by .25mm or too large & not enough meat to turn down the saver body to a tap in fit. I'm going to make a stepped adapter ring out of aluminium, it will need to stick out a little further than usual due to how close the diameters are but shouldnt be too much of an issue.

[Nasher]

Thanks all

Originally Posted by Steve509926

Hi Nasher, never used bearing savers, but could they not be made an interference fit by wrapping with PTFE tape?

It probably would work, but I'd run the risk of getting to the slipway and finding one or more of them missing and have zero protection for that bearing, so I'd be in a worse position than ever.

Originally Posted by beerbelly

mine has the alloy ones supplied by de graaf no springs inside either just a grease nipple and a small hole that shows its full by a tiny squirt of grease coming out they have been on since 2015 been knocked on and off loads of times and are a little dented and battle scared but still secure and working fine .i change my bearings every other year and have never took a set out that actually needed changing.hope that helps

It's good to know your Ali ones have been in and out a lot without any issues.
You have prompted me to relook at the ones I found, and they are indeed like you suggest with no spring.
I'll have another look as I do prefer the ones with the spring as it provides a small amount of constant pressure to help resist any water ingress.

Originally Posted by beamishken

I've had the same issue trying to find a replacement bearing saver & struggling to find the exact size. I found they were either too small by .25mm or too large & not enough meat to turn down the saver body to a tap in fit. I'm going to make a stepped adapter ring out of aluminium, it will need to stick out a little further than usual due to how close the diameters are but shouldnt be too much of an issue.

Glad it's not just me!
Your solution would work really well I think, but my bearing savers already stick out a long way and I'd like to try not to have them any further out.

[smallribber]

https://www.rib.net/forum/f49/sealed...ubs-90891.html

[smallribber]

https://www.rib.net/forum/f49/excell...ies-90784.html

[Nasher]

Thanks Smallribber, but I think I'm missing what in those threads helps me?

[smallribber]

The stainless steel ones I bought were a tight fit and might fit your application. Given the cost of them (very cheap) and they work well. Might be worth a try. You are talking a measurement accuracy that can only be tested in real life in my view

[User name]

I'd go with the oversized ones and if they don't fit, turn them down. It'll take no effort at all to take off 0.16mm

[smallribber]

Originally Posted by User name

I'd go with the oversized ones and if they don't fit, turn them down. It'll take no effort at all to take off 0.16mm

I had to Dremel a tad of the ones I bought

[beerbelly]

i mentioned the lack of springs to the guy at de graaf he thought the ones without were a better design for not having them .whatever i have never had any sign of water getting in at all.and trust me after having a wheel come off a previous trailer i take the condition of my trailer very seriously and thoroughly check everything on a regular basis