Fork tube chrome vs granite

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David Lahey
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Fork tube chrome vs granite

Post by David Lahey »

Last weekend I took a tumble amongst some very scratchy granite rocks and one fork tube got some gouges. A few of them were deep enough to expose the steel under the chrome. I rode the bike back to camp so that fork seal is toast.
Today I decided to try a home remedy for the gouges that I had heard but not tried for myself.
First I removed the high bits along the edges of the gouges using a hand oil-stone.
Then I degreased the damaged area and filled the gouges with Araldite.
Then I removed the excess Araldite with a well-worn file.
I could feel that a couple of the gouges still had an edge. I was going to put some more Araldite on but decided to try superglue instead. So I degreased the area again and put on some super glue. When that set I used the worn file again to remove the excess.
I then smoothed the area with some 5000 grit wet and dry paper.
In the photos it looks like the gouges and pits are still there but that's only because the Araldite and super glue are transparent. It feels fine with no detectable edges to damage the new seal I'm planning to fit.
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David Lahey
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Re: Fork tube chrome vs granite

Post by David Lahey »

Today I replaced the wrecked fork seal then took it for a test ride. No leaks so far.
I also did a bit of suspension tuning while I was at it, reducing the fork spring preload.
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brt650
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Re: Fork tube chrome vs granite

Post by brt650 »

Hello David,
Just wondering how the superglue repair is holding up? I've done the same on some rear mono type shocks on trail bikes with great results. I just clean up the surface with an oil stone then clean it with brake clean. The superglue bonds really well. After drying I use wet and dry and it gives a very smooth finish.
Cheers
Brian
David Lahey
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Re: Fork tube chrome vs granite

Post by David Lahey »

brt650 wrote:Hello David,
Just wondering how the superglue repair is holding up? I've done the same on some rear mono type shocks on trail bikes with great results. I just clean up the surface with an oil stone then clean it with brake clean. The superglue bonds really well. After drying I use wet and dry and it gives a very smooth finish.
Cheers
Brian

Hi Brian yes it's still going well thanks. I've only ridden it for about 30 minutes since then though. I reckon the fix will last a lot longer than it takes for me to get organised enough to buy a new one.
David
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llewdaert
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Re: Fork tube chrome vs granite

Post by llewdaert »

Hello David, can you give me some indication if you believe the superglue was the correct final stage for this repair -please? I have a hard chrome rod from my tractor that rusted partially. I repaired with belzona expoxy, but need to go another layer,and I am concerned the thin epoxy top layer, will not be durable as the rock hard base.
Any thoughts from others will be welcome
David Lahey
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Re: Fork tube chrome vs granite

Post by David Lahey »

llewdaert wrote:Hello David, can you give me some indication if you believe the superglue was the correct final stage for this repair -please? I have a hard chrome rod from my tractor that rusted partially. I repaired with belzona expoxy, but need to go another layer,and I am concerned the thin epoxy top layer, will not be durable as the rock hard base.
Any thoughts from others will be welcome


The superglue has stayed in place so far, even where it is quite thin.
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Re: Fork tube chrome vs granite

Post by Kurt »

We tig weld the scratch with a stainless wire on parts that we don’t rechrome or replace at work on hydraulics. 309L rod for carbon steel.
You then should be able to file this back and polish it in with an emery belt.
Can also dot weld on smaller parts.
llewdaert
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Re: Fork tube chrome vs granite

Post by llewdaert »

Thanks for the replies, The item is track adjust/tension rod on a caterpillar 931b.The stainless weld repair is golden advise, and will be my next effort if the belzona fails.The rod seal holds grease, and does not move much I think,only during adjustment [ then it should stay there until the track chain-or other drive train parts wear]. It also has a large spring cush arrangement to absorb big shocks to the track assembly-and I suspect does not move too much,but will stroke the tensioner rod.
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